Electronic environment 3 2018

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3.2018 EMC in product development

SETTING THE EMC REQUIREMENTS

EMC från bricka till bricka

• EMC & SKÄRMNING

EMC och Articifiell Intelligens

DEL 23

Diverse metoder för EMC-tätning >> PART 2

DESIGN / HARDEN EQUIPMENT FOR ESD IMMUNITY + KALENDARIUM SID 4 + Ny el-standard SID 6 + ÖGAT PÅ SID 8-9 + FÖRETAGSREGISTRET SID 36–39 >>>


Electronic Environment #3.2018

Reflektioner

Dan Wallander Chefredaktör och ansvarig utgivare

Nya länder utmanar dominanten USA

D

en flitiga läsaren av denna publikation har kanske noterat kalendariet som alltid återfinns i början av tidningen. Utan att lägga någon större vikt vid hur de sammanställs, så kan jag ändå berätta att det ligger en hel del letande bakom resultatet. Det undertecknad har reflekterat över de senaste åren är att antalet konferenser inom våra elektronikområden internationellt verkar öka i antal. Är det en trend vi ser, och i sådana fall vad beror den på? En förklaring kan vara att nya ämnesområden på ett självklart sätt tar plats under elmiljö-hatten, IoT för att ta ett exempel. IoT är knappast någon dagsslända och det finns ett stort behov av att träffas i olika forum och utbyta kunskap. Beprövad erfarenhet inom elmiljö måste då appliceras i nya sammanhang och ställas inför nya utmaningar. En annan kan vara att ”nya” länder utmanar dominanten USA med möten inom våra elektronikområden. Bara under november 2018 arrangeras in-

tressanta konferenser i Japan, Sydafrika och Indien. Och det känns ju som en naturlig utveckling. Antalet evenemang är en sak, mottagandet något helt annat. Så, hur ser då trenden ut där? Lite olika men väldigt intressant, skulle jag säga. På vissa håll kämpar man med deltagarantalen medan på andra ser trenden positivare ut. I slutet av augusti genomfördes exempelvis E±MC Europe 2018 i Amsterdam. Konferensen var välarrangerad och välbesökt med ca 500 delegater vilket är ett bra resultat. Extra roligt för svensk del är att professor Jan Carlsson under konferensen valdes till ny ordförande för den internationella styrkommittén. Och EMC Europe kommer åter till Sverige. År 2022 arrangeras konferensen i Göteborg. Mer information om det kommer, var så säker. I DET HÄR NUMRET av Electronic Environment fort-

sätter vi med del två i vår nya artikelserie; ”EMC in product development”. Denna del har titeln ”Setting the EMC Requirements” av Lennart Has-

selgren. Miklos Steiner fortsätter sin serie ”EMC från bricka till bricka”, med del 23 där vi fortsätter att titta på olika metoder för EMC-tätning. Michel Mardiguian presenterar den sista delen om Electrostatic Disarge (ESD), med titeln ”Design / Harden Equipment for ESD Immunity”. Den avslutande delen om ESD är också Michel Mardiguians sista del i den planerade sviten av artiklar i tidningen Electronic Environment. Ett stort tack Michel för all kunskap och erfarenhet vi fått ta del av, i både artikelform och under intensiva EMC-kurser! Merci Michel pour toutes les connaissances et les expériences que nous avons reçues, sous la forme d’article et sous des cours intensifs EMC! Men, det kommer mer från Michel! Om detta tänker jag berätta i nästa nummer, lagom till Jul. Till dess önskar jag en trevlig läsning!

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Electronic Environment Ges ut av Break a Story Communication AB Mässans gata 14 412 51 Göteborg Tel: 031-708 66 80 info@breakastory.se www.breakastory.se

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HELSINGBORG Box 13060, SE-250 13 Helsingborg +46 42-23 50 60, info@emp-tronic.se

Adressändringar: info@justmedia.se Tekniska redaktörer: Peter Stenumgaard Miklos Steiner Michel Mardiguian Våra teknikredaktörer når du på info@justmedia.se

STOCKHOLM Centralvägen 3, SE-171 68 Solna +46 727-23 50 60

Ansvarig utgivare: Dan Wallander dan.wallander@justmedia.se Annonser: Caroline Östling caroline.ostling@justmedia.se Dave Harvett daveharvett@btconnect.com

www.electronic.nu – Electronic Environment online

Omslagsfoto: Istock Tryck: Billes, Mölndal, 2018 Efterpublicering av redaktionellt material medges endast efter godkännande från respektive författare.


Electronic Environment #3.2018

Redaktörerna Peter Stenumgaard

Design / Harden Equipment for ESD Immunity

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Ur innehållet

Civilingenjör Teknisk Fysik och Elektroteknik (LiTH 1988) samt Tekn Dr. Radiosystemteknik (KTH 2001). Arbetade fram till 1995 som systemingenjör på SAAB Military Aircraft där han arbetade med elektromagnetiska störningars effekter på flygplanssystem. Detta inkluderade skydd mot exempelvis blixtträff, elektromagnetisk puls (EMP) samt High Power Microwaves (HPM). Han har varit adjungerad professor både på högskolan i Gävle och Linköpings universitet. Peter arbetar idag till vardags på FOI. Han var technical program chair för den internationella konferensen EMC Europe 2014 som då arrangerades av Just Event i Göteborg.

Miklos Steiner

2 Reflektioner 3 Redaktörerna 4 Konferenser, mässor och kurser 6 Ny el-standard 8 Ögat på – Diverse metoder för EMC-tätning, del 23 10 Teknikkrönikan – Peter Stenumgaard 11 Rapport från svenska IEEE EMC 12 Noterat 13 EMC in product development – Step 2 17 Konferenser

Miklos har elektromekaniker- högskoleutbildning för telekommunikation och elektronik i botten samt bred erfarenhet från bl a service och reparation av konsumentelektronik, konstruktion och projektledning av mikroprocessorstyrda printrar, prismärkningsautomater, industriella styrsystem och installationer. Miklos har sedan 1995 utbildat ett stort antal ingenjörer och andra på sina kurser inom EMC och är också författare till den populära EMC-artikelserien ”ÖGAT PÅ”, i tidningen Electronic Environment. Under många år var Miklos verksam som EMC-konsult, med rådgivning och provning för många återkommande kunder. Mångårig erfarenhet från utveckling av EMC-riktiga lösningar i dessa uppdrag har gett Miklos underlag, som han med trovärdighet kunnat föra vidare i sina råd, kurser och artiklar.

18 Design / Harden Equipment for ESD Immunity 33 Branschnytt

Michel Mardiguian

34 Noterat 35 Författare i Electronic Environment 36 Företagsregister

>> STEP 2

Setting the EMC requirements

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Michel Mardiguian, IEEE Senior Member, graduated electrical engineer BSEE, MSEE, born in Paris, 1941. Started his EMC career in 1974 as the local IBM EMC specialist, having close ties with his US counterparts at IBM/ Kingston, USA. From 1976 to 80, he was also the French delegate to the CISPR. Working Grp on computer RFI, participating to what became CISPR 22, the root document for FCC 15-J and European EN55022. In 1980, he joined Don White Consultants (later re-named ICT) in Gainesville, Virginia, becoming Director of Training, then VP Engineering. He developed the market of EMC seminars, teaching himself more than 160 classes in the US and worldwide. Established since 1990 as a private consultant in France, teaching EMI / RFI / ESD classes and working on consulting tasks from EMC design to firefighting. One top involvment has been the EMC of the Channel Tunnel, with his British colleagues of Interference Technology International. He has authored 8 widely sold handbooks, two of them being translated in Japanese and Chinese, plus 2 books co-authored with Don White.

www.electronic.nu – Electronic Environment online

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Electronic Environment #3.2018

Konferenser, mässor & kurser

Konferenser & mässor

Föreningsmöten

ESA Industry Days 2nd Edition: Additive Manufacturing for RF/Microwave Hardware

Se respektive förenings hemsida::

16-17 oktober, Noordwijk, Netherlands

IEEE

EDI CON USA 2018, Electronic Design Innovation

Nordiska ESD-rådet

www.ieee.se

17-18 oktober, Santa Clara, USA

www.esdnordic.com

5G Wireless Networks

SER

Batteri- och UPS-anläggningar

20-21 november, Stockholm www.stf.se Högspänningsinstallationer och jordningssystem

20-21 november, Stockholm www.stf.se Internet of Things, IoT, teknik och protokoll

22-24 oktober, San Jose, USA

www.ser.se

20-21 november, Stockholm www.stf.se

MILCOM 2018

SNRV

Maskinsäkerhet och CE-märkning, grundkurs

29-31 oktober, Los Angeles, USA

www.radiovetenskap.kva.se

40th Annual Meeting and Symposium of the Antenna Measurement Techniques Association (AMTA 2018)

SEES

4-5 december, Malmö www.sis.se

www.sees.se

EMC in Military Equipment and Systems

4-9 november, Williamsburg, USA Embedded Conference Scandinavia 2018

6-7 november, Kistamässan, Stockholm Asia-Pacific Microwave Conference (APMC 2018)

6-9 november, Koyoto, Japan Global Electromagnetic Compatibility Conference (GEMCCon 2018)

7-9 november, Stellenbosch, Sydafrika International Conference on Electromagnetic Interference & Compatibility (INCEMIC 2018)

13-16 november, Bengaluru, India electronica 2018

13-16 november, Munchen, Tyskland Radio & Wireless Week 2019

20-23 januari, Orlando, USA

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Kurser

6-8 februari, Mölndal www.emcservices.se

Hybrid vehicles and EMC

18 oktober, Mölndal www.emcservices.se Cellulär IoT

23-24 oktober, Stockholm www.stf.se Maskinsäkerhet och CE-märkning, grundkurs

5-6 november, Göteborg www.sis.se Grundutbildning i ATEX

7 november, Göteborg www.sis.se Maskinsäkerhet och CE-märkning, grundkurs

15-16 november, Stockholm www.sis.se www.electronic.nu – Electronic Environment online

TIPSA OSS! Vi tar tacksamt emot tips på kurser, föreningsmöten och konferenser om elsäkerhet, EMC (i vid bemärkelse), ESD, Ex, mekanisk, termisk och kemisk miljö samt angränsande områden. Publiceringen är kostnadsfri. Sänd upplysningar till: info@justmedia.se. Tipsa oss gärna även om andras evenemang, såsom internationella konferenser!


Electronic Environment #3.2018

Komponenter för kraftelektronik, EMC & RF/Mikrovåg

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See emission and immunity sources at components level! Using the EMC-Scanner during the early stages of design enables you to detect potential emission or immunity problems before they become integrated into the product and expensive to correct. See what an EMC scanner can do for you, visit our website www.detectus.com.

See it before you

it!

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Electronic Environment #3.2018

Ny el-standard Listan upptar ett urval av de standarder som fastställts under december 2017 och under januari och februari 2018. För varje standard anges svensk beteckning, internationell motsvarighet (om sådan finns), europeisk motsvarighet (om sådan finns). Om den europeiska standarden innehåller ändringar i förhållande till den internationella anges detta. Dessutom anges svensk titel, engelsk titel, fastställelsedatum och teknisk kommitté inom SEK. För tillägg framgår vilken standard det ska användas tillsammans med men för nyutgåvor och standarder som på annat sätt ersätter en tidigare standard framgår inte vilken denna är eller när den planeras sluta gälla.

SS-EN 60068-2-10, utg 1:2005/A1:2018 IEC 60068-2-10:2005/A1:2018 • EN 60068-2-10:2005/A1:2018 Miljötålighetsprovning – Del 2-10: Provningsmetoder – J: Mögelbildning, med vägledning Environmental testing – Part 2-10: Tests – Test J and guidance: Mould growth

ning - Bedömning av funktionsegenskaper hos värme- och fuktkamrar Environmental testing – Part 3-6: Supporting documentation and guidance – Confirmation of the performance of temperature/humidity chambers SEK TK 104: Miljötålighet FASTSTÄLLELSEDATUM: 2018-09-12

SEK TK 104 Miljötålighet SS-EN IEC 60721-2-7, utg 1:2018

Fastställelsedatum: 2018-09-12 SS-EN 60068-2-74, utg 1:2001/A1:2018 IEC 60068-2-74:1999/A1:2018 • EN 60068-2-74:1999/A1:2018 Miljötålighetsprovning - Del 2-74: Provningsmetoder - Xc: Vätskeprov Environmental testing - Part 2-74: Tests - Test Xc: Fluid contamination SEK TK 104: Miljötålighet

SEK TK 104: Miljötålighet FASTSTÄLLELSEDATUM: 2018-09-12

FASTSTÄLLELSEDATUM: 2018-09-12

SS-EN IEC 60721-3-1, utg 2:2018

Ny Tabell 1 (och Annex 1) med uppgifter om vanliga vätskor. SS-EN IEC 60068-3-5, utg 2:201X IEC 60068-3-5:2018 • EN IEC 60068-3-5:2018 Miljötålighetsprovning - Del 3-5: Bakgrundsinformation och vägledning - Bedömning av funktionsegenskaper hos värmekamrar Environmental testing - Part 3-5: Supporting documentation and guidance - Confirmation of the performance of temperature chambers SEK TK 104: Miljötålighet

IEC 60721-3-1:2018 • EN IEC 60721-3-1:2018 Miljöklassificering – Del 3-1: Grupper av miljöfaktorer och deras strängheter – Lagring Classification of environmental conditions – Part 3-1: Classification of groups of environmental parameters and their severities - Storage SEK TK 104: Miljötålighet FASTSTÄLLELSEDATUM: 2018-09-12

I denna utgåva har alla klimatklasser ersatts med nya enligt SS-EN 607212-1.

FASTSTÄLLELSEDATUM: 2018-09-12

SS-EN IEC 60068-3-6, utg 2:2018 IEC 60068-3-6:2018 • EN IEC 60068-3-6:2018 Miljötålighetsprovning – Del 3-6: Bakgrundsinformation och vägled-

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IEC 60721-2-7:2018 • EN IEC 60721-2-7:2018 Miljöklassificering - Del 2-7: Miljöförhållanden i naturen - Fauna och flora Classification of environmental conditions – Part 2-7: Environmental conditions appearing in nature – Fauna and flora

Sammanställningen är ett urval av nya svenska standarder på det elektrotekniska området fastställda av SEK Svensk Elstandard de senaste tre månaderna. För kompletterande information: www.elstandard.se

Din produkt – vårt fokus.

Vi vet vad som krävs för att din produkt ska uppfylla regulatoriska krav.

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www.electronic.nu – Electronic Environment online


Electronic Environment #3.2018

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Electronic Environment #3.2018

Ögat på Vad alla bör känna till om EMC:

EMC från bricka till bricka, del 23

EMC & SKÄRMNING DEL 6: Diverse metoder för EMC-skärmning EMC måste tas om hand i alla delar, såväl på elektrisk som på mekanisk systemnivå, och på alla nivåer i en utrustning på ett systematisk och planerat sätt. Vi har i tidigare artiklar ingående behandlat skärmning med hjälp av metallplåt och kapsling. Detta angreppssätt är inte alltid det mest effektiva, ibland inte ens tillämpbart. Denna gång tittar vi på s.k. generaliserad skärm och metoder som praktiseras som generaliserad skärm. ZONTÄNKANDE När man börjar planera ett system kan man börja med att tänka efter vilka olika elektromagnetiska miljöer, som kommer att förekomma för olika apparater: vilka zoner (= miljöer) behövs eller finns redan, hur många olika zoner är optimalt och var skall man placera zongränserna osv. I militära applikationer tillämpade man förr ofta taktiken att ha en enda zongräns mot omvärlden och minimera antalet interna zoner. Man realiserade konstruktionen genom att kapsla in den i skärmande metal�lådor och använde skärmande kablar mellan lådorna. Detta tankesätt ger helskärmade konstruktioner, en lösning som inte passar överallt. T. ex. i civila fordon måste man vara ytterst restriktiv med vikten och kostnaderna, därför är helkapslande metallådor inte förstahandsvalet. TILLÄMPNING AV ÅTGÄRDER Ett jordplan i ett kretskort eller en monteringsplåt i ett elskåp kan agera och kan beskrivas som en generaliserad skärm. Dessa har nämligen kopplingsreducerande egenskaper. Alla åtgärder som reducerar koppling sorterar under begreppet generaliserad skärm. (Se figur 1.) Störning kan definieras som oavsiktlig energiläckage från källa till offer. Störning kopplar ofta via parallella vägar. Det finns tre huvudsakliga kopplingssätt: fältkoppling, överhörning (eg. närfältskopling) och ledningsbunden (ledd) koppling. Störningen ändrar ofta karaktär och övergår från en form till en annan med många kombinationsmöjligheter i kopplingskedjan. (Se figur 2 .) Zongränsen skall åstadkomma en kopplingsreducering för ett eller flera elektromagnetiska fenomen och kan genomföras på flera sätt (se figur 3). Generellt kan sägas att zongränsen är en topologisk begränsningsyta, som representerar kopplingsreduktion mellan olika elektromagnetiska miljöer (zoner). GENERALISERAD SKÄRM Figur 1 illustrerar begreppet generaliserad skärm. Figuren kan föreställa ett kretskort med monterade komponenter eller ett apparatskåp med monterade apparater eller ett datorrum med sammankopplade skåp med digital utrustning. I närheten av plåten råder en annan elmiljö än en bit därifrån; zongränsen uppåt bestäms av avståndsdämpning av fält och är inte lättbestämd och därmed osäkert.

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Det är bra om konstruktören ändå är medveten av denna zongräns och ser till att den inte överträds. Ofta får praktiska begränsningar bestämma denna ”osynliga” gräns; man gör volymen, dvs avståndet, så stor som möjligt. Praktiska försök får ofta avgöra om avståndet mellan t. ex. olika apparater, kablar eller kretskort är tillräckligt. Kretskort: se till att andra kort eller kablar inte kommer alltför nära och punkterar denna zongräns, dvs medför störning. Datorrum: se till att belysning och dess kablage hålls på behörigt avstånd från apparaterna och signalkablarna. Inga hängande armaturer, t. ex. Kopplingsreducering kan likställas med en generaliserad skärm, dvs. en åtgärd som reducerar koppling. Åtgärden kan vara: • Isolering (t ex transformator, optokopplare, icke-jordning) (figur 4.) • Avstånd (fält avtar med avståndet) (figur 1.) • Polarisering (t. ex. två spolar som ligger på en linje eller parallellt kopplar mer än de som ligger vinkelrätt till varandra; antenner med olika polarisation) (figur 6.) • Närhet till jordledare, -nät, -plan (minskad fältkoppling) • Mer eller mindre omslutande metallhölje (skärm) • Filter och överspänningsskydd (verksamma endast för ledda störningar) SKALSKYDD Begreppet skalskydd förekommer ibland i litteraturen och kan definieras som: • Skalskydd = Apparatiserad zongräns, som skall dämpa alla ledningsbundna och fältöverförda störningar till nivåer lägre än en maximalt accepterad nivå, vilken i sin tur är lägre än inom zonen befintlig utrustnings tålighet. • Skalskydd = En volym omgiven av ett mer eller mindre tätt metallskal (skärm), i vilket filter monteras. Del av skärmen (generaliserad skärm) kan vara jordplan eller avståndsseparation. (Se figur 5). • Filter placeras alltid i en zongräns, dvs monteras i skärmvägg eller i kanten på jordplan.

www.electronic.nu – Electronic Environment online

Miklos Steiner info@justmedia.se


Electronic Environment #3.2018

Figur 1

Figur 5

Figur 2

Figur 6

Figur 3

Figur 4

Figur 6 www.electronic.nu – Electronic Environment online

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Electronic Environment #3.2018

Teknikkrönikan EMC och Artificiell Intelligens ARTIFICIELL INTELLIGENS (AI) är ett samlingsbegrepp inom vetenskap och teknikutveckling där man försöker göra maskiner lika intelligenta som människor. Området har de senaste åren blivit mycket hett och stora möjligheter förutspås inom framtida produkter med AI-tillämpningar. AI bygger i grunden på att algoritmer tränas och lärs upp på stora datamängder och att man sedan förutsätter att data som sedan uppstår i den aktuella tillämpningen kan hanteras med hjälp av den genomförda inlärningen.

DET HAR OCKSÅ uppstått svårigheter att reproducera vissa resultat, vilket lett till en diskussion om forskningsmetodiken inom området [1]. AI-experten Ali Rahimi på Google har gått så långt att han jämför AI med alkemi [2], då han menar att den trial-and-error-metodik som ML bygger på är mycket lik den som använts inom alkemi. Detta då nya resultat kom fram inom alkemi genom att man prövade sig fram utan att ha en grundläggande förståelse för de inblandade delarnas struktur och egenskaper.

ETT DELOMRÅDE inom AI är maskininlärning (ML) där algoritmer mer eller mindre prövar sig fram genom trial-and-error för att lära sig hantera en viss tillämpning. Här har man visat mycket kraftfulla algoritmer för att exempelvis spela GO, känna igen objekt i bilder eller känna igen mänskliga röster. En svårighet med detta är att man oftast inte vet varför en algoritm fungerar eller inte och man har inte några tydliga kriterier på varför en algoritm ska väljas framför en annan.

OAVSETT VAD MAN tycker om denna tillspetsade liknelse så illustrerar den en grundläggande utmaning som är intressant att fundera på för EMC-egenskaper hos applikationer som bygger på AI. Ur EMC-synpunkt följer en utmaning relaterad till att ML-algoritmer bygger på att man tränar dessa för en tillämpning som förutsätts representeras av mängden träningsdata som använts. Om det sedan uppstår oväntade EMC-problem som leder till att data in till algoritmer blandas med okontrollerade störningssignaler så är

det inte otänkbart att tillämpningen kan påverkas i okontrollerad riktning. UTVECKLINGEN AV AI-TILLÄMPNINGAR är således ytterligare en trend som betonar vikten av gediget EMC-arbete i de system som sedan nyttjar dessa tillämpningar. Detta gäller särskilt tillämpningar med höga krav på säkerhet, som exempelvis förarlösa fordon.

[1] Matthew Hudson, “Artificial intelligence faces reproducibility crisis”, Science, 16 Feb 2018, Vol. 359, Issue 6377, pp. 725-726. [2] Rafi Letzter, “Google AI Expert: Machine Learning Is No Better Than Alchemy”, LiveScience, May 7, 2018.

Peter Stenumgaard info@justmedia.se

ELSÄKERHET Nya köldmedier kan vara brandfarliga De nya, mindre miljöstörande, köldmedier som börjat användas i värmepumpar, avfuktare och andra liknande produkter kan vara brandfarliga. Det ställer därför extra höga krav på både elsäkerhet och tillförlitlighet för er som producent. Säker produkt genom provning RISE har laboratorier speciellt utrustade för test av produkter som innehåller ett brandfarligt köldmedium och kan även utföra andra tester som till exempel prestanda- och EMC-test. Med hjälp av RISE expertis, säkerställer ni en säker produkt gentemot marknaden. RISE är Sveriges forskningsinstitut och innovationspartner. I internationell samverkan med företag, akademi och offentlig sektor bidrar vi till ett konkurrenskraftigt näringsliv och ett hållbart samhälle. Våra 2 300 medarbetare driver och stöder alla typer av innovationsproccesser. RISE är ett oberoende statligt forskningsinstitut som erbjuder unik expertis och ett 100-tal testoch demonstrationsmiljöer för framtidssäkra teknologier, produkter och tjänster. www.ri.se

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Kontaktperson: Daniel Olsson daniel.olsson@ri.se 010-516 58 43

www.electronic.nu – Electronic Environment online


Electronic Environment #3.2018

Information från svenska IEEE EMC EMC Europe genomfördes i år i Amsterdam. En handfull svenska presentationer fanns med men liksom de senaste åren så är det ingen stor tyngd från oss. Vi får alla hjälpas åt att satsa på en kraftsamling till 2022 då konferensen återkommer till Sverige.

Leverantör av det mesta för de flesta inom EMC

Det är nu ungefär ett halvår kvar till Brexit. För många företag börjar det bli hög tid att fundera på hur detta kan påverka dem med avseende på bland annat EMC och radiodirektiven. Det är såklart mycket som fortfarande är osäkert eftersom förhandlingarna mellan EU och Storbritannien pågår för fullt, men några saker kommer sannolikt att inträffa. Storbritannien kommer inte att vara en del av den inre marknaden. Detta innebär att ett svenskt företag som köpt produkter tillverkade i Storbritannien går från att vara distributör till importör, med tillhörande ansvar. I varje fall för produkter som sätts på marknaden efter utträdesdagen. I vilken grad det kommer att gälla för befintliga produkter verkar vara föremål för förhandlingarna som pågår. Det verkar också finnas mycket kvar att förhandla om kring hur befintliga godkännanden och certifikat (till exempel medicintekniska produkter) ska hanteras. Som vanligt här på hösten vill jag uppmana alla att förnya sina medlemskap. Jag själv ser fram emot den nya publikationen som jag flaggade för tidigare (IEEE Journal on Electromagnetic Compatibility Practice and Applications) som ser ut att ingå i medlemskapet i IEEE EMC Society från och med nästa år. Höstens första möte förbereds som bäst i skrivande stund, och vi återkommer även med inbjudan till årsmöte som troligen äger rum i början av december.

RONSHIELD AB Rangstagatan 18 SE-124 54 Bandhagen Tel. +46 8 722 71 20 Mob. +46 70 674 93 94 E-mail: info@ronshield.se

Christer Karlsson Ordf. Swedish Chapter IEEE EMC

www.ronshield.se

EMC LIFE SIMPLIFIED SLIPP OMPROVNING SLIPP DYRA FILTERLÖSNINGAR Vill du förenkla ditt utvecklingsarbete? Tillsammans går vi igenom din produkt och du får råd och stöd så att den klarar EMC-kraven.

SLIPP ONÖDIGA KORTRUNDOR I TID FÖR LANSERING

Med våra råd sparar du både tid och pengar - du hamnar rätt direkt. Vi har en bred kompetens inom EMC - allt fordonselektronik till installationer och sateliter i rymden - vi vet vad som krävs för du skall klara kraven. Kontakta Tony Soukka, tel 0734-180 981 eller tony@emcservices.se för att diskutera ditt projekt.

EMC SERVICES

KNOWLEDGE IN REALITY

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Electronic Environment #3.2018

Noterat Gävle för forskarutbildning i elektronik och industriell ekonomi

ATT HÖGSKOLAN FÅTT rätt att starta forskarutbildning i ämnena industriell ekonomi och

i elektroteknik innebär att lärosätet nu har hela utbildningskedjan, från grundutbildning till forskarutbildning, inom bägge dessa områden. – Vi har fått väldigt bra utlåtanden från externa sakkunniga, och forskarutbildningsrätterna är ett kvitto på att vi har en forskningsmiljö som är stark, säger Magnus Isaksson. Han menar att detta innebär en statushöjning för hela lärosätet, att det blir lättare att rekrytera doktorander, behålla kompetenta forskare och attrahera externa projekt. – Här har skett en otrolig expansion när det gäller forskning, vi håller hög klass och vi publicerar våra resultat i de bästa vetenskapliga sammanhang och tidskrifter. Bara de senaste

Råd om elsäkerhet vid klimatförändringar STIGANDE MEDELTEMPERATURER, kraftigare skyfall och åskoväder – när elanläggningar skadas eller hamnar under vatten, kan de bli strömförande och människor kan skada sig och få elchock. Nu finns information och tips till konsumenter om hur man skyddar sig och sin bostad. 2017 tog Elsäkerhetsverket fram en handlingsplan för klimatanpassning och nu finns information på webbsidor och ett informationsblad att ladda ner på myndighetens webbplats. Syftet är att höja anläggningsinnehavares kunskap om klimatförändringarna. – Alla behöver förstå hur klimatförändringar kan påverka bland annat elsäkerheten. Vi vill underlätta för bostadsägare och andra privatpersoner så att de vet vad som är viktigt vid en akut händelse samt hur de kan förebygga skador genom att tänka elsäkerhet från början, säger Jennie Andersson, teknisk expert vid Elsäkerhetsverket. Vid en översvämning där elanläggningar hamnar under vatten, kan farliga situationer

uppstå eftersom det finns en ökad risk för att elektroniken blir vattenskadad. Då ökar också risken för att människor drabbas av brand och elchock i samband med kortslutning. Även åska, ras och jordskred medför risker kopplat till elchock och elbrand. – Vi ger konkreta råd om vad man ska göra när en översvämning eller ett ras drabbat elanläggningen. Det går också att läsa om hur man ska tänka när man ska bygga nytt och ta beslut om placering av sin bostad eller val av material och placering av elcentralen, säger Jennie Andersson. Informationen från Elsäkerhetsverket går också att nå via Klimatanpassningsportalen, www.klimatanpassning.se, en ny webbplats där man kan läsa det mesta om hur samhället ska anpassas till klimatförändringar. Portalen är ett samarbete mellan en rad myndigheter, och drivs av Nationellt kunskapscentrum för klimatanpassning vid SMHI. KÄLLA: Elsäkerhetsverket

fem åren har antalet publicerade vetenskapliga rapporter ökat med 62 procent, säger Magnus Isaksson. Industriell ekonomi är ett viktigt tekniskt ämne i den lite mjukare delen inom teknikområdena. Forskning som kan ingå är till exempel inom logistik, innovationer och innovationsprocesser. Elektroteknik är ett brett område och vid Högskolan bedrivs forskning inom trådlös radio, radio- och mätteknik, signalbehandling, robotik och reglerteknik- och sensorer. KÄLLA: Högskolan i Gävle

Skydda dig och din bostad

Vid översvämning och ras

Sänk dina projektkostnader – använd standarder! Underlätta och förbättra ditt arbete inom det elektrotekniska området – www.elstandard.se

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Fastställer all svensk standard inom elområdet Svensk medlem i IEC och CENELEC

Tryck och Layout: Universitetstryckeriet, Karlstad, 2018. Foto: Mostphotos

Högskolan i Gävle får forskarutbildning i industriell ekonomi och i elektroteknik. – Detta är en mycket viktig pusselbit i ett större strategiskt arbete för vår utveckling framåt, säger Magnus Isaksson, professor och ledare för projektet kring forskningsutvecklingen vid Högskolan i Gävle.


Electronic Environment #3.2018

EMC IN PRODUCT DEVELOPMENT

SETTING THE EMC REQUIREMENTS INTRODUCTION. This article is a part of a series of texts that will deal with the EMC challenge in terms of project management and the practical EMC activities at different stages in the project flow. Different companies all have their own way of describing their project flow, so to keep it simple we will use the labels as given in Figure 1. We can call it a generic project flow. The picture only describes the basic outline of the work packages. These articles will describe the actual practical work we want to do in the project to “make EMC work” in a time- and cost-efficient way. Each part of our series will fill in the details for each part piece by piece. www.electronic.nu – Electronic Environment online

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Figure 1 . Picture of typical project flow

”You might look at this as tedious paper work that slows down the project – but you will sleep better at night and be better prepared for questions” In this article, we move to the second block in the flow chart - setting the EMC requirements. This is an activity I have noticed is briefly touched in projects, and many times only referred to as finding some type of standard as fast as possible, so that we can go on with the real work - design. I will try to lift up the status for this work and maybe make it more concrete what are the actual activities? ATTITUDE TO REQUIREMENTS First of all – why do we do this? What is the intention of having EMC requirements? The requirements are your defense and not your obstacle. They are your solution to make sure that you will have as few problems in the future - in the project and in operation (customer claims etc.). So do not go for the lowest and – as you were hoping – cheapest requirements. Pick the correct and relevant requirements. EMC requirements are meant to prevent inter-system degrading influence. That means, that you will never see these problems when running your component in your development lab. But, your customer will notice when they do not get their radio communication needed or when the lightning strikes nearby. It is better that you find the problems before them. So do not regard EMC as something you have to sneak around, cutting the corners in some cunning way. Correct requirements will help you in the long run. UNDERSTANDING THE REQUIREMENTS Do not just copy-paste old requirements. Take your time to understand the technical intention with them. Part of that work is done in the prestudy as described in the previous article. Here, we talk more about the paperwork part of it. What reference documents are we using, and why? Do the previous requirements meet the expectations of our customers today? Maybe the standards have been updated, which means new tests may have been added (or removed). Also, do not try to negotiate with the customer about using older requirements, believing that they are easier to pass. You must ask yourself the question: why did they update the specification at all? Many times it can be that: – The older limits were extreme, and it turned out that no one passed them. After a review, a more realistic level was introduced – The older test proved to be virtually impossible to create in a normal lab, and no one thought of that when they extrapolated the test level with a straight line. And those capacitors in the setup are in the wrong place, by the way. – That old test was invented in the 70:s by a clever engineer when commercial test equipment was not yet available. Now, when he is retired, someone finally had the courage to replace that test with a modern setup that is possible to calibrate. In addition, be aware of that standardized requirements are based on diplomatic compromises in standardization committees. You may need to

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add requirements based on the actual environment. For instance, companies manufacturing keypads and touch panels know that enhanced protection for ESD is needed when selling to e.g. northern Sweden. What requirements shall be included? Some may be too high to design for, so let us handle that with a disclaimer or some amount of warranty cost. Examples: damages caused by direct lightning strike; new failures because the customer extends signal cables outside expected range; customer co-location of your product with very sensitive equipment.

Figure 2. Different types of requirements: legal, customer, market and environment based

SELECTING STANDARDS Many engineers expect that this is the only thing you do when you talk about EMC requirements. Ask the EMC lab what standards they can recommend, and then we will hopefully get a pass when we test. Let us say you would do the same when selecting your DC power? “What voltage do we need for the PCB input?” “Well, I am not sure, but let’s try 12VDC. Pick one of those DC/DC converters, solder it to the wires and then we will see how it goes in the power lab next month. It will probably work fine” No, you would normally check your preconditions, and also include temperature, electrical safety and other aspects. The same goes for EMC – in addition to the radiated emission limit you also check for the need of immunity to RF field, pulses, power quality, ESD and so on. “We have done this before, so it is not much difference” – you might say. OK, you have reference projects to look at when you start the new one, and that is excellent! But still: why did you have to design a new product? Why not keep selling the old one? No, something has changed, and you have made improvements and maybe also have expanded the scope for the application. So, the preconditions have changed and consequently also the requirements – including EMC. You will then have to look into the EMC

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Electronic Environment #3.2018

standards and select the ones that covers – The intended use of the product (including all options) – Different frequency ranges for the requirement (like power frequency harmonics and RF emission) – Both immunity and emission (sometimes they are split up) – Different markets One way is to look for existing published standards - surfing the CENELEC site for instance. Before you buy the standard, you can read the scope in a preview and see if it is relevant for your application. You may also want to check for upcoming revisions of the standards you are going to use. At IEC (and CENELEC), you can search for draft and work in progress. ETSI is very generous in providing free drafts in advance, providing you with all the details about what is around the corner. Take the opportunity to test against future requirements while you are at it, and your approval documentation will last longer. For some products, you will receive a specific EMC requirement from the customer – such as vehicle manufacturer or the military ones. So, you do not have to look around, but these might be very complex and you might have to look through the references to check what they really contain. Some of the specifications are new and fresh, other ones should have been updated long time ago (in my view). SETTING PRECONDITIONS Sometimes, you may sell to a customer having a specified scope. For instance, you may sell to a military customer who declares that the product will be installed in a protected environment (e.g shielded enclosure having lightning protection). Make sure to have this in writing, since this will drastically influence both design and testing! This precondition needs to be included both as design and test input, as well as the user instructions. A well formulated disclaimer is always good to have - users can often be very innovative, and then possibly blame the manufacturer when it brakes. Another example is the vehicle industry. Here, the manufacturer of the vehicle has two options for approvals (the homologation process): either complete vehicle type approval - or approval by subcomponent. As a supplier of the component, you must be sure to check with the customer which way to go. Will you have to make a component approval, or can you leave that to your customer (who makes a complete vehicle approval). DOCUMENT STRUCTURE A way to keep track of things is to have a specific record for how the approvals for the product is to be achieved. Create a Product Approval Specification – PAS. This is a high-level document containing a list of – End-user applications (domestic, industrial, marine etc.) – Specific customers request (e.g. a US company having their own references) – Market needs (Australian specialties) – Legal requirements (CE etc) – Product variants (Radio added to some of them) A part of this document is the time plan for approvals: what approvals do you need, and how long ahead do you need to plan for it? Things you need to check are: – What certification is needed? What is the source for the requirement? Legal reference, customer reference, rumor (someone said he/she thought it was necessary, but did not know why) – Where can we get the stamps? What options do we have, and when do we need to book the lab? – Lab capacity, can we pick any one or do we need a specific one with particular competence/equipment (example, capacity to handle high mechanical loads, cooling, weight etc) Example of approvals that are common are: – CE self approval – CE with type approval module – Local national approvals (outside EU) – E-marking (vehicles) – Ships classification (insurance company requirement) – Lab accreditation (customer requirement) In addition: do not mix up EMC requirements with other approvals. Someone at the market department may say, that we need a CB certificate for this country. However, a CB certificate (CB = Certification Bodies) is mainly relevant for electrical safety, as is UL (Underwriter’s Laboratory, the US/international S-marking). They can not be used for EMC. Also, you

will sometimes hear that an accredited laboratory is absolutely needed, but no one knows why. Be aware, that lab accreditation is only required for a reduced range of testing. Quite often, an EMC lab meeting the technical performance for the tests is quite sufficient. There are several labs with some 30 years of experience who never bothered about the cost of accreditation (e.g. working with military testing), but still know their stuff. If you have a set of favorite labs that you work with – including non-accredited ones – you might enjoy a better flexibility in your test planning. The difference is that you will have to check the credibility of the lab yourself, which is not too bad. It forces you to know more about EMC testing, which will be crucial in the coming articles. I often meet customers who ask me these types of questions at a very late stage in the project, and I realize that they should have prepared these issues a long time ago. And now they find themselves in a bad situation, where they can not find the resources in time - so the project time plan is delayed, managers are pushing, discussions go on for long times and the cost goes up. And they also discover that the testing was more complex than they hoped for (will be discussed in later articles). On the other hand, there may be engineers who say this processing is a drastic overkill. “We go to the EMC lab and use the generic EMC standards every time, so what is the problem?” And of course, if you have a tight group of experienced design engineers, they know their job well. Small companies often work faster and more efficient with EMC (if they have the experience). But new colleagues will join you, and for them this is not self-explaining. When the guy who kept all the know-how and spread the word in the good old analogue way (talking to each other) retires or quits, the cost for re-inventing the wheel of EMC will go up. TRACING One hidden cost in a product manufacturing company is the time allocated to discussions about the requirements. Why do we have them, and why these levels? One good way to reduce this cost is to write these things down on a paper that you can find. There are two major obstacles in this process: – Write it down (when you have the time) – Find the document afterwards (what ID shall it have, and where to store it) The solution can be to assign time to the most experienced engineer (who does not actually have time for this, since everybody is asking questions about the requirements… but still), in combination with having a document structure not only for the production but also for supporting documents. While you are at it, do not only put a tag on the requirement. Take the time to append at least the following information: What is the actual threat that the test is simulating? From where did we get the test levels? When and how did we say that we needed these requirements? Example: space industry is very good at tracing their requirements, and also in some military industries. This tradition is now spreading into the vehicle industry, where some manufacturers are migrating into using links in data bases instead of referring to a corporate standard in the shape of a PDF document. THE FUNCTIONAL PERFORMANCE CRITERIA When you set the EMC test requirements for immunity (or susceptibility, as it is sometimes called), you can not just set the test level. You must also specify the tolerable product behavior for each type of test. These are listed as generic descriptions in several EMC standards, and normally use the designation letters A, B and C. By nature, IEC can not agree with ISO on these labels – so ISO standards use roman numbers (unless you apply the older versions, where you use ABCD but of course with another content). In very plain words, we could describe the meaning of the letters as follows: A: it works OK B: it works so-and-so, but basically not too bad C: a bit worse than B, but some type of reset is OK So, what does it mean for this particular product? The text is mostly too generic to use - you have to be specific! Letter A means that it works OK, and that range is mostly found in the design specification which focuses on the expected performance. And C could be listed as a straight forward push on the reset button. But what about letter B? Nobody specifies so-and-so behavior unless you are utterly forced to do so - like by the EMC standards.

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Figure 3 – Performance failure criteria (A,B and C)

Some engineers might say this is up to the EMC lab. They are used to EMC testing, and it is better they do it since they know what it means. Just read the standard, it is listed there. But this is regrettably impossible for the EMC lab to perform. The performance criteria are closely related to the functionality of the product. And they did not build the product - you did. So, it is the responsibility of the manufacturer to specify the criteria and deliver them to the lab so they can apply them during the tests. When you do the EMC tests, you monitor the test object and check the response. Which response is it, and what does the customer expect? What percentage of variation is acceptable, and in what parameters? Write it down and pass it on to the lab! Often, the engineers writhe and squirm when faced with this question - quasi-function is not popular. Try to look at it from another perspective: let us talk about the stability of a heavy truck. When it is driving on a straight road at 90 km/h. it goes straight. Then you press the truck into a curvy road, and it wiggles a bit. How much do you accept, before you get car-sick? And finally, you drive into a sharp curve. Let us say that the truck should stay on the road at 30 km/h. At 90 km/h, you drive off the road, but the driver shall not die. If we convert this to EMC, we might say that 10 V/m = straight road 30 V/m = curvy road 100 V/m = sharp curve Normal operating mode = 90 km/h, 30 km/h Monitored parameter: maybe something better than the color of your face (green/red/white). Or: you might compare this with test levels for transients, if that is more interesting. The bottom line is that you do not have the same expectations for all tests and not even for all test levels within one test. So, please, for your own good: specify the performance criteria at the beginning of the project and save a lot of discussion and time – and money!

Compliance Matrix. This will include the technical parts of the PAS, like the EMC standards selected. If you do not use a specific data base tool, this matrix is effectively made as a straight forward Excel spreadsheet. You can use this spreadsheet during the entire development project and follow up the progress. As time goes on, you add more detail about specific test methods (conducted emission, radiated emission etc). It will be used both as an input to the design (what to prepare for in the test) as an output (how are we doing regarding pass/fail). In addition, you can use this document as a check on what you agree on with your customer, if you have a specific one (e.g. a vehicle manufacturer). Many times, such customers gladly add new requirements and – not the least – new test conditions without thinking of the consequences. Such “would be nice to have” request might make your test time explode and also the complexity in test preparation. If you like, you can integrate this compliance matrix with your PAS, as separate sheets in the same document, making it easier to update. INPUT AND OUTPUT As a summary, we find the following interface conditions to the other parts of the project flow. Input from prestudy: - Types of EM environments - Market areas - legal requirements that are need - Expected customers - what do they expect - Differentiation on product configurations Output from this stage: - Product Approval Specification (PAS), including time plan for approvals - Requirement specification – technical, including traceability of legal and customer requirements and performance criteria - first release of EMC Compliance Matrix You might look at this as tedious paper work that slows down the project – but you will sleep better at night and be better prepared for questions. Hopefully, you will also have a reduced number of never-ending meetings on the subject “now, what did we say about EMC?” I believe you will gain in the end. If you have ideas and comments on this article, please feel free to mail me! Some might also recognize my short examples, and if you want to add something that would be an interesting talk.

PREPARING FOR COMING WORK IN THE PROJECT So, when you have prepared all this information it is now time to make use of it – instead of just putting it in a folder and let it mold until you go to the EMC-lab. Make a checklist on what is to be prepared and carried out. In complicated projects where we are involved, we propose to generate an EMC

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Lennart Hasselgren, Lic Eng. EMC Services lennart.hasselgren@emcservices.se


Electronic Environment #3.2018

Konferenser Rapport från EMC Europe i Amsterdam UNDER SISTA VECKAN i augusti genomfördes EMC Europe 2018 i Amsterdam. Konferensen var välbesökt med över 500 personer varav 20 från Sverige. De svenska deltagarna kom bland annat från FOI, Huawei, Ericsson, Trafikverket, Volvo, Luleå tekniska högskola, Rise, Chalmers, Provinn och Qamcom. Huawei var också silversponsor för konferensen. Även måndagen, som var vikt för workshops och tutorials, drog många besökare. En av de mer välbesökta workshoparna var den som var inriktad mot Automotive EMC. Konferensen bestod som vanligt också av en utställning med 26 utställare. Utställningen var mycket välbesökt, speciellt då fika och lunch intogs i samma lokal. Under konferensmiddagen delades utmärkelsen Best paper ut till Christopher L. Holloway, Matt T. Simons, Marc Kautz, Perry F. Wilson, and Joshua A. Gordon för sitt bidrag ”Development and Applications of a Fiber-Coupled Atom-Based Electric Field Probe”. Bidraget visar på möjligheten att mäta elektriska fält med en Rydbergs-atom-baserad mätprobe. Mätmetoden bygger på att Rydberg-atomerna, som

EMC Europe i Amsterdam lockade över 500 deltagare.

finns i mätproben, fungerar som en RF-tilloptisk omvandlare. Det applicerade elektriska fältet skapar förändringar i atomen vilket i sin tur orsakar ett optiskt frekvenssvar, som är beroende av det elektriska fältet. Teknik möjliggör mätningar över ett stort frekvensband. Christopher Holloway höll även ett uppskattat keynote speach på EMC Europe i Göteborg 2014 med samma tema.

Under torsdagens möte med konferensens styrgrupp (ISC) valdes Jan Carlsson, Provinn, till ny ordförande efter Andy Marwin. Nästa EMC Europe kommer att gå av stapeln i Barcelona (2-6 september 2019), och sist men inte minst vill vi också nämna att 2022 kommer Sverige att anordna EMC Europe i Göteborg. Jan Carlsson, Provinn, och Kia Wiklundh, Qamcom Research & Technolog

Hej, det är vi som är Proxitron! Vi kan bli din leverantör av utrustning och service

Rickard Elf

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0141-20 96 53 rickard@proxitron.se

Kontakta oss redan idag! Vi diskuterar gärna dina specifika servicebehov, kontakta oss för ett förslag eller ett kostnadsfritt besök.

Jonas Johansson 0141-20 96 55 jonas@proxitron.se

Proxitron AB – 0141-580 00 – info@proxitron.se – www.proxitron.se

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Electronic Environment #3.2018

>> Part 2:

DESIGN / HARDEN EQUIPMENT FOR ESD IMMUNITY Preamble: As for any organized EMI control, ESD protection consist in anticipating or correcting the unwanted effects of an hostile electromagnetic ambient. Like many EMI threats, ESD manifests through conducted and radiated phenomena, with the latest being often the dominant mode. But there is a unique aspect to ESD, not found in common radiated EMI episodes where the victim box and cables are illuminated by a uniform field. Instead, ESD generates locally a strong field pulse, typically > 1kV/m near the discharge point, dropping quickly as one move away. Therefore, although ESD hardening should be part of a general EMI control, not handled as a separate constraint, some classical EMC solutions may not be sufficient and should be complemented by additional protections.

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Looking at Fig. 5.1, ESD immunity can be considered at the following stages: • At component level • At circuit board level • By software and noise cancellation features • At internal packaging & wiring level • At housing/cabinet level • At installation and environment level In theory, one could implement a full ESD protection at one of those levels only. Yet, costwise, it is more efficient for ESD control to be shared between several levels. Like the skins of an onion, there are several layers, from the physical envelope (metallic or not) of the product down to its active center core (the ICs that perform the essential functions). Each layer corresponds to a certain power level and frequency band of the signals being handled. For instance: – going from the external envelope where inputs/outputs can handle tens, or eventually hundreds of Volt, like for power supply, levels as low as 1Volt and few tens of mA are reached after a few layers, when getting to the chip core. – in terms of frequency, the functional bandwidths range from kHz for low speed analog up to hundreds of MHz, eventually GHz with high speed digital processing. Whatever based on clamping, filtering or shielding, no single device, regardless it protects from damage or prevents errors/signal alterations, can perform alone for all these different amplitudes and frequency domains. Instead, protection elements are best installed at the boundary of these layers, with current handling capacity, bandwidth and physical size that are commensurate to the layer which is to be protected downstream.

ters of each IC pin, including I,V curves and mismatch. This is simulated by software tools, with results correlatable to those of a real test pulse. An other need urged IC manufacturers into designing overvoltage suppression: the Latch-Up, typical of CMOS, but also found with bipolar technologies. It manifests as low resistance path, bridging Vdd with Vss if a transient current exceeding few 100mA is applied, generally ending-up in IC damage by overheating. Some passive overvoltage protections can be built-in the chip. Others have been devised, which are not integrated in the chip but implemented in the module package, hence do not suffer the same dimensional restrictions, like ZnO varistor ring laid on the periphery of the chip carrier or substrate Fig. 2 . Efficient integrated protections, up to 15kV, are achievable, but at the expense of chip real-estate. High speed I/Os can be protected on the chip, but at some prejudice to their speed, due to the capacitance of the integrated diodes. If no technology or vendor can be found with built-in ESD protection that matches the objectives and constraints, application-specific protections are necessary. This is especially true for lines which are connected to “user-touchable” items, mostly connectors, as explained next. Input

Output

Vcc

Bond Pad Vss Die edge a) Simple diodes protection on input or output

Software

Ceramic substrat.

b) CMOS Transistor ”Crowbar” protection

I/0 area: buffers & voltage translators

Chip Core Die

}

PHYSICAL ENVELOPE. Metallic? Reg. plastic? Conduct. plastic?

2

e 3

Rwell

IC MODULE

EXTERNAL CABLES

1

Components

Discrete electromechanical devices

PCBs

c) Resistor + Transistor Protection

4 1) Varistor paste 2) Common Ground bus 3) IC substrat 4) Protected lead

d) Multi-lead protection

Discrete internal wiring

User´s interface

Fig. 1. The several layers to be considered for an ESD protection strategy. Each layer corresponds to a power level and frequency band of the signals being handled. Filtering, shielding or transient protectors are selected accordingly.

1 . ESD PROTECTION AT COMPONENT LEVEL A first degree of ESD immunity can be achieved by selecting components (logic or analog ICs, operational amplifiers, resistor networks etc..) that already have built-in ESD protections.

IC Technology

Type of embedded protection

ESD withstanding, no-damage level (HBM test, 150ns pulse)

CMOS CMOS Bipolar

unprotected (bare chip) clamp diode + series Resist. Input: - Schottky diode (Vbr:30V) - Crowbar transistor - Thyristor Output, unprotected Diodes+Resist.+Low-pass filter

50V (for 0,50µm rule) 2 to 4kV

Low-speed drivers

700V 2kV 5kV 2kV Up to 15kV

Fig. 2. Few widely used ESD protections, embedded in the IC. Table shows the

1.1 Integrated Circuits with internal ESD protections Thanks to the huge growth of the ICs market and the need for cost/size reduction, manufacturers are now integrating some ESD protections in the chip itself. However, as often, this is conflicting with an other trend : size reduction, by shrinking the IC features down to the sub-micron region, results in thinner oxide thickness and traces width, such as even the protection devices like diodes, crowbar transistors and polysilicon resistors can no longer handle the ESD pulse energy. The efficiency of these techniques are evaluated through the standard ESD tests, or a more recent evaluation tool: the Transmission Line Pulse (TLP), injecting a calibrated square pulse into the device via a RF-type jig. By varying the pulse amplitude / duration, more insight is obtained for critical failure parame-

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withstanding voltage (Human Body Discharge

1.2 Additional ESD protection; When is it needed, and how much? Rather than adding external Transient Voltage Suppressors (TVS) to each component, purchasing parts which are ESD-immune (for instance with a 2kV to 4kV ESD grade) is cost-effective. Yet, in many cases, an additional protection is necessary, selected to fulfill the expected ESD immunity of the equipment, because: a) integrated resistors, zeners and crowbars are efficient against damages but cannot prevent errors due to few volts transients induced by ESD.

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Electronic Environment #3.2018

b) the 2kV or 4kV vendor-specified immunity is only granted against a human body (HBM) discharge, with a maximum current of 2.6 A (for a 4kV grade). This covers the IC during handling, manufacturing assembly, packing/unpacking or maintenance. In actual machine life, and during ESD tests, ESD currents up to 30A, for 8kV(direct contact), and 45A (air discharge) can be stressing the equipment. Most circuits will never be directly exposed to such currents, but some will, like ICs that connect directly to a user-touchable connector pin, manual switches, etc...or that are arc-reachable (air discharge) These added protections can perform by: – decoupling (clamp diodes, crowbars and capacitors): the current is bypassed to Gnd or +Vcc – blocking ( inductances): a high impedance is opposed to the ESD current – absorbing (lossy ferrites and resistors): the ESD pulse is dissipated into heat Depending on the selected components, their action can: – insure a damage-free, but not an error-free operation, or – filter the high frequency part of ESD spectrum, hence preventing errors with short pulses (<10ns), but cannot attenuate long ESD pulses, typical of a direct injection, or – insure both survival and error-free protections.

VDD

VSS

310 000 ns

360

PESD0603-140

Voltage response (40V/div)

320 280 240 200 160

Clamping voltage

120

. D . . . .. . .. .. . .. ... A . . ........................................................... . . ......... ....................... ... ..... ... . . ................... ... ... ................... ... .. ...... ... ................ ... ...... . .... ... ... ... ...... . .. .. ..

B

1000V TLP Pulse

800V TLP Pulse

80 40

500V TLP Pulse

0 0

20

40 60 time (10 ns/div)

80

100

Fig. 3. Voltage at the IC pin of a keyboard PCB when applying a 1kV indirect ESD at 10cm. Although not destructive, the 130Vpeak pulse cause a lock-up in a frozzen state, requiring a Power-Off /On action (from Ref. 3). Right: TVS with low parasitic capacitance (0,25pF, size 603 (Source Tyco-Raychem): the applied 800V ESD pulse is clamped to 80V.

Following are commonly used ESD protection components, mounted close to the IC to be protected: a) TVS (discrete or integrated). Leadless SMT devices, with 2 to 8 termi-

nals are available (Fig.3), handling the full current of a 15kV IEC-type discharge. b) Series resistances limiting the current on the sensitive, high impedan-

ce inputs

pF or more can be added, depending on what capacitive loading is tolerated by this line w/o affecting the performance. While transient protectors do not eliminate low level glitches (those not high enough to cause damage, but exceeding the detection threshold), decoupling capacitors will. d) Capacitive filtering next to the power input pin. A 100nF ceramic ca-

pacitor can be added, even if not considered necessary at the initial circuit design (some Vcc supply pins can cause a logic error if the parasitic pulse has enough amplitude). There is now a general trend among IC manufacturers to incorporate such capacitors in the chip itself, using diffused junction capacitances. When cascading external clamping devices with chip internal protection diodes, watch for clamping coordination: if a fast acting diode exists already inside the chip, it parallels the external clamp and one must make sure that the first one will not react faster. This would cause the faster but fragile device to prevent the triggering of the bigger one, and to be destroyed by an energy that it cannot handle. Always place some series resistance or a small inductance between the two. A last advice is to make sure not to use a too fast technology, unless it is absolutely needed for a specific function. Often, logic families with 2 or 3ns transitions are used all over the board, assuming that ”the faster the better”. 2. ESD PROTECTION AT THE PCB LEVEL (Internal Circuitry) The printed circuit board is the area where the improvement/cost ratio is the largest. The effort invested in sound PCB layout will be paidoff times over by a gain in immunity which can be drastic, often at no additional parts cost. There are many cases where ESD immunity was built at PCB and I/O levels so that even without additional shielding of the housing, the equipment withstand ESD levels above 10kV. The guidelines given here are a short compilation of time-proven, non self-conflicting rules, that build-up the ESD defense at no prejudice to EMC or product performances, because they all concur to high immunity and low emissions, up to > 300 MHz. 2.1 Reducing the field-to-PCB coupling mechanisms Beside the direct contact by the ESD intruder, two ESD field-coupling mechanisms are playing a role in the PCB susceptibility, as described before: H-field coupling and near E-field (or capacitive) coupling).

100ns

100 ns/div

c) Capacitive decoupling next to critical signal pins. On signal inputs, 30

a) Against H- field coupling: the rule here is to minimize the exposed loop areas by checking all the runs against signal-to-return loops or Vcc-to-zero-volt loops ( Fig. 4): • No signal or Vcc trace should run without a close Gnd return (trace or, preferably, plane): Use ground planes or largest possible copper lands, to act as noiseless ground and shield. Double-sided boards with maximum un-etched copper on one side are better than single-sided boards, multilayers being even better. b) Against E- field coupling: Here the risk is some invisible capacitor between the PCB and the charged source: the gun tip, the edge of the HCP or VCP during the test, or a person’s finger during an actual event. Any exposed sensitive trace, high impedance IC input, or IC package itself can capture a capacitive current during the abrupt ESD voltage change. Such target should be protected by a ground plane underneath ( or above): • Minimize the length of open-ended high impedance lines. • Do not allow unused inputs to be floating, hence making easy targets for capacitive pick-up. • Never run critical signals (Clock, Reset, Watchdog etc...) near the board edge. Such locations are prone to capacitive coupling from a nearby ESD. This applies even to PCB with full ground planes, since copper planes themselves are often etched near the edge of the epoxy board. • For reinforcing the screening effect of the ground plane at the board edges, use a peripheral ground trace on the opposite (component side) face of the board, frequently connected to the ground plane by via holes. It can also serve as a collector ring for the I/O decoupling capacitors.

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OV

multilayered chip structures, the chip’s internal reference plane is tied to the PCB’s Gnd plane by the many Gnd pins of the IC package, such as the whole PCB plus IC assembly benefits from a monolithic ground plane.

5V

Vcc input decoupling capacitor Local Vcc decoupling

CLK GND

RST

Induced voltage HF filtering

Ground Ring

Fig.4. Example of a vulnerable PCB layout. Long capacitors traces make the decoupling unefficient, while offering pick-up loops to the ESD field. The groundring shifted in-board does not protect the clock trace on the card edge, exposed to capacitive coupling. The capacitor decoupling the Reset line is far from the IC: an induced noise in series in the loop will entirely appear on the critical input.

2.2 PCB Connectors areas A particular attention must be given to PCB connector areas, especially those receiving directly cables from the outside. Normally I/O cables should be shielded, or at least decoupled, at their point of entry in the enclosure, but there is often no such facility and they plug directly onto the PC Board. Since these cables are privilegied ESD pick-up antennas, they can ruin the best PCB design. Such connectors should preferably be on a same edge, or same angle (two perpendicular edges) of the board. This prevent ESD-coupled currents from external cables to cross the full board, causing longitudinal ground noise, since even ground planes that seem perfect are not: small planes have always some parasitic inductance, typically 0,1nH / cm. Thus, a 1A/ns current pulse will cause 0,1V of ground noise per cm of trip. Therefore, when a PCB connector is also the equipment frontier with the external world, it must be treated as a potential ESD entry port. Incoming lines can be filtered at the board edge by: – discrete ceramic capacitors, with ultra short leads, – surface-mount type capacitor arrays – capacitors teamed with miniature ferrites, discrete or integrated in the connector 2.3 Signal Ground vs Chassis ground Wether or not the PCB 0-V reference should be grounded to the equipment chassis and where is a recurring issue. EMC-wise, it is generally better to make the signal Gnd equipotential with the chassis, especially in the PCB area. Yet some designers, for preventing low frequency ground loops, keep the PCB isolated from the chassis ground. Considering the frequency domain covered by an ESD, this issue is irrelevant since even a floated PCB become virtually grounded above few tens of MHz anyway. If a PCB ground has to be floating, a VHF connection to chassis must be established, via a few nF ceramic capacitor, preferably in the I/O connector area. 2.4 PCB hardening with plastic products An increasing number of equipments are designed with plastic housing, with no intention to apply a conductive coating. In such case, if all but one of the EMC constraints can be met with a non-conductive envelope, it would be a waste to change for a full metallized plastic just because of the ESD requirement. As a result, the PCB itself becomes the only physical barrier to ESD coupling. Even if only Indirect ESD is anticipated, a bare PCB and its active circuitry are first class targets for field induction. Here, all that have been said before has to be emphasized, especially regarding E-field, capacitive coupling. A PCB with at least a full ground plane on one side and a ground ring on the edge is a must. Since practically all complex ICs (µPs, ASICs, Flash memories, DSPs etc ...) have

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* SUMMARY OF ESD PROTECTION MEASURES AT PCB LEVEL * • Select ICs which are inherently ESD protected to ≥ 2kV ( HBM test) • Clamp/ decouple critical inputs and Vcc pins, close to the critical ICs • Select logic technologies with longer risetimes, compatible with the function • Use PCB with ground (0volt) plane, w/o slots. Multilayers are best. If single layer/single side have to be used, landfill (do not etch) voids, with copper linked to all 0-volt nodes. • No critical traces ( Clock, RST etc...) near the board edges. • Keep space for I/O ports decoupling with SMT components, right at entry points • All general EMC rules have a positive effect on ESD immunity, provided that the high frequency spectrum ( >300MHz) is kept in mind. 3. ESD PROTECTION BY INTERNAL WIRING and MECHANICAL PACKAGING Several practices in component selection, placement, mounting, bonding and cabling can upgrade an equipment defenses against ESD. Two things are to consider for their selection: some components or subassemblies can be generators of internal ESD, some others can be carriers or even victims. In the ESD sources category are the parts made of insulating material that can be momentarily or permanently rubbing, rotating sliding etc ... for instance : – paper trays or containers – plastic pulleys or rollers with rubber belts or conveyors – cooling fans with polycarbonate blades – H igh Voltage dc power supplies When such elements are selected, preference should be given to those which the manufacturer has made antistatic or static-free, through material selection, conductive additives or shielding. All metal parts around these items should be grounded to the metallic mainframe. High voltage dc supplies, due to the non-null value of their static field, can charge by influence all insulated parts (even metallic parts if ungrounded) that are in the path of the electric field lines. Such high-voltage dc sources should be surrounded by a grounded Faraday shield, neutralizing their stray capacitance vs. nearby components. In extreme cases of serious internal static generation, active static eliminators can be installed that ionize the air, allowing the separated opposite charges to recombine. ESD protection of keyboards and flat displays The other category of components i.e. the ”carriers” or ”victims” is by far the largest. A special problem is posed by the keyboards and specially the membrane type. First, these devices need an opening in the shield, creating a privileged entry port for ESD coupling. Moreover, they have a high chances of being hit by a direct discharge, whose arc directly reaches the touch-sensing circuits under the domes or capacitive arrays (Fig. 5). One need to know what sort of unwanted response to such discharge is acceptable or not. The criteria could be as liberal as “no-damage” only, or more demanding in cases where an illegal keyboard action could cause a dangerous reaction from the equipment. Several solutions exist for keyboards immunity, if the ESD risk is moderate: • thin metal interlayer, multipoint grounded to the chassis so that the ESD current does not penetrate the inner part of the keyboard. Cheap versions exist where the flexible contact layer has simply a grid of conductive ink. • for the outer membrane where symbols are printed, use a thick (0.3mm) polyester film which can resist to arc punch-through, and keep signal traces of the underlayer far from the edges to avoid a lateral flashing. • Add 10 kΩ series resistors on the signal traces coming from the membrane, before the active circuits. Contactless “virtual switches” keyboards using capacitive detection are naturally protected against ESD because their glass or thick dielectric touch panel can stand 15kV without breakdown. However the dielectric panel is sometimes porous, allowing cascades of internal arcing to reach the internal circuitry. Also, the capacitive current through

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the dielectric can exceed the detection treshold, causing an undesired switching. In both cases, 10kΩ series resistors, like for the membrane keyboard are a simple and efficient solution. TVS are not recommended because their significant parasitic capacitance could interfere with the capacitive sensor circuitry. Regular button-and-pluger keyboards are not necessarily exempt from DESD intrusion, depending on the free air trip between finger tip and the PCB traces underneath. One solution consist in creating a labyrinth path for the key. An other solution is using a soft plastic overlay on the PCB, which can withstand up to15kV for the air discharge. This overlay is embossed above each switch, increasing the arc path length.

A similar problem occurs with LCD displays mounted flush on an equipment façade (Fig. 6). A discharge can reach the edge of the LCD frame, not necessarily fully evacuated by the housing. Making things worse, the LCD frame is often connected to an internal signal Gnd, such as the full discharge current can flow via the ribbon cable to the equipment boards. The solutions depend on the nature -conductive or not- of the housing : • With metallic (or conductive plastic) housing: – a tight electrical bond on all sides, between the LCD rim and the aperture edge. – a transparent, conductive overlay like ITO (Indium Tin Oxide), with a typical 3-10Ω/sq. surface resistance, with edges bonded to the aperture stepped edge.

Membrane keyboard

a)

Contact circuit

• With a plastic housing, the display is treated as a sacrificed entry port for ESD: use a shielded flat cable, with the shield connected one end to the LCD frame, the other end to the PCB ground, or add 10kΩ series resistors on the signals coming out from the LCD, right at the cable entry on the main PCB

IESD going into PCB Traces

Capacitance (touch sensitive) keyboard

Capacitance sensor

Equipment box

. . : . .. ... . : . .. ... . : . .. ... . : . ..

LCD

.. : . .. ... . : ... ... . :... ... . : .......... . OV

Metal frame

IESD PCB

b)

Ribbon cable

ESD current to PCB ground

Fig. 6. ESD entry path with LCD displays

Finally, ESD has to be considered in regard to the location of sensitive items like critical PCBs, magnetic sensors or storage media and their associated circuit etc.... Not only their location should avoid the proximity of the ESD sources described above, but also the proximity of possible ESD entry paths like cooling or displays apertures, seams, openings etc... Near these places, shielding protection of the housing will be poor and ESD currents will re-radiate inside. If covers are bonded by straps, these straps will generate a strong H-field during a discharge. No sensitive components or their wiring should be placed close to them.

Thin steel membrane with deformable domes (grounded) or elastomere layer

Insulating layer with conductive shorting patterns undemeath

c)

If, even after these precautions, an excessive ESD pick-up may still exist by coupling into Comm. Mode (cable-to-chassis) loops, use C.M. ferrite beads and sleeves over the whole cable. This solution will work best if the circuit is a low impedance one. Add-on ferrites exist in form of split beads and yokes. Some have been developped especially for flat cables and recent lossy ferrites materials can provide 6 to 15 dB of reduction above 30 MHz, which is precisely the domain where ESD couplings become critical.

PCB with electro-mechanical switches

Labyrint path

Internal wiring, exposed to ESD re-radiation inside, will also carry some induced ESD noise. Besides the precautions at their termination into the PCB connectors, the following guidelines will prevent excessive pick-up: – avoid long runs of cables along cover seams, hinges, bonding wires. – do not press cable harnesses and specially flat cables against the edges of metallic covers which are likely ESD targets : move them away from the edges, or use thick shield – avoid large Vdc-to-Gnd and signal-to-Gnd loops. Always carry a signal close to its own return.

PCB

Flexible plastic overlay

Fig. 5 a) Risk of ESD damage or malfunction with buttonless keyboards. b) membrane keyboard with EMI and ESD shielding solutions. c) solutions with electromechanical switches.

4. ESD PROTECTION BY BOX SHIELDING AND ENVELOPE DESIGN If the components, PCBs and internal elements have been hardened to a certain ESD level V1, while the specification requires a level V2 > V1, the housing is what is left to make-up for the difference. The shielding precautions for the housing are basically the same as for any EMI susceptibility problem, bearing in mind that the 300 MHz or higher spectrum of

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concern obliges the designer to consider the possible leakage of any seam and slot exceeding a few centimeters. This is not saying that a machine which relies on its housing for ESD hardening should be shielded with the same precautions as any VHF equipment or sensitive Radio Frequency device ! In the late 1960’s when ESD problems started to be a nightmare with computers, and its mechanisms were not understood yet, manufacturers of large computers were making all the covers RF-tight, entirely plating their frame with nickel etc... Main frames took-on the appearance a vault. Additional drawbacks are that the designer may not be familiar with these techniques which drastically increase the cost of the cabinet and associated hardware, complicate maintenance, accessibility, and may degrade with aging. So, typically, we are looking for shielding methods which are economical, will remain unaltered after intensive use of the equipment, and provide a moderate shielding effectiveness in the range of 10 to 30dB (i.e. a reduction of electro magnetic field by a factor of 3 to 30 times). But they must provide this attenuation up to the 300-1000 MHz region.

4.2 Maintaining Shield Integrity with Metal Housings A metal housing already has the advantage of being a naturally efficient shielding barrier. All the efforts of the designer should be aimed at not spoiling this barrier with excessive leakages: • All metal parts should be bonded together. Any floated item is a candidate for re-radiation : instead of being part of the continuous barrier, such piece may become a capacitive coupler to the electronics inside. Grounding of such part is not crucial; what counts is its equipotentiality with the other parts of the envelope (Fig. 7). • For cover seams, slots, etc., how frequently they should be bonded is a design objective. A 10 cm leakage is worth about 15 dB of shielding against a 1ns pulse. If the goal is closer to 20 or 30 dB, seams or slots should be broken down to 5-3 cm. For permanent or semi-permanent closures, this means more screws or welding points or a conductive gasket. For covers, hatches, etc.. it means flexible contacts or EMC gaskets. The often mentioned λ/10 rule implies that, for a 1ns rise time of the ESD, the distance between jumpers should be less than 0.1 m. Keeping such bonding intervals, and assuming that no sensitive circuits are located closer than 0.1m from this seam, a 15dB shielding can be expected. If more is needed, or if sensitive circuits are closer from the seam, distance between bonding straps should be reduced, which become rapidly unpractical.

4.1 Some Shielding Basics Those readers not familiar with shielding basics are encouraged to read the Sept 2016 and March 2017 issues of EE magazine where EMI shielding principles and applications have been addressed. Here, we will focus on shielding applications that are more specific to ESD hardening. Shielding effectiveness is defined as the ratio of the incident field to the residual field (the part that gets through). • If bonding at the hinged side only leaves an excessive length of ung asketed seams, additional bonding points are necessary. In this case, For E (or H)fields : SE (dB) = 20 Log Ein / Eout ( or Hin / Hout ) use a few soft springs scattered along the cover edges. A variation of this shown in caption b) is using sections of spring contacts called If shields were perfect, Eout, Hout, and therefore Pout would be zero. finger-stocks. Several types are available, such as low-pressure, knife In practice, a shield behaves as an attenuator, performing on two cascaedge, and medium pressure. They require an adequate control of presded mechanisms: Absorption which increases thickness, conductivity, sure by manufacturing tolerances, but they are extremely dependable. permeability, frequency, and Reflection which increases with * Surface Grounding buttons or “sticky pads”, which are fairly compliant to conductivity and * Wave impedance. gap variations thanks to their spring loading, can also by mounted simply by press-fit or self-threading stud. • The most threatening part of the ESD spectrum being in the high frequency region, any metal barrier with thickness of 0.1 millimeter Intruder or more, will provide an excellent absorption loss. • Conductive paints or coatings will not perform well by absorption, because their film thickness represents only a few skin depths or less, hence a low absorption loss. Conductivity is the key: Silver, copper and zinc films would still provide some absorption loss in the range of Electronics what is aimed for ESD, i.e. 10 to 40 dB. Graphite paints, with relative VESD conductivity of 10-5 to 10-6 will provide marginal or null absorption. Regarding the ESD-related radiation, two situations may exist: a) IESD: discharge does not occur on the conductive housing of the equipment itself, but rather it occurs nearby. In this case, the discussion on absorption and reflection applies. Furniture discharge will be most threatening because this is where H field predominates and the reflection term will be minimal. b) The discharge occurs right on the housing (direct ESD). In this case the previous approach on near-field and reflection losses is irrelevant. What is impinging the metal barrier is not a field but already a current. This current then penetrates the metal barrier, is attenuated, and what is left on the other side re-radiates inside. In any case, the only chance of a shield to perform well is to have either an excellent conductivity, as close as possible to copper, or a sufficient thickness to represent at least a few skin depths Yet, housings are not made like continuous metal cubes. Slots, seams, apertures etc... will inevitably leak. It is important to know its weak points, in order to establish some realistic objectives. In the high frequencies domain, where any solid metal would provide hundreds dB or shielding, these are never seen because seams and discontinuities fully spoil the metal barrier. ESD belongs to this case, so when chasing shields openings, one must remember that holes and seams are critical in areas that: a) Are likely to receive an ESD, and b) Have sensitive components or wiring just behind. An ESD-hardened box does not have to be a 120dB Faraday cage. A large slot should not be a designer’s hang-up if it is far from any critical circuit.

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Fig. 7. ESD coupling via floating metal parts. They encourage capacitive coupling, especially near the edges and protruding areas. If they are connected to the rest of the casing, they will remain equipotential.

• For a higher grade of shielding (20 to 40 dB), a continuous conductive bonding of seams is necessary, since a 30 dB attenuation at 300 MHz (λ/2 = 50cm) would require screws or rivets every 1.5cm ! Continuous conductive joints are available in several forms and stiffnesses (Fig. 8). The hollow conductive elastomer gasket is rather inexpensive to use because its elasticity compensates for large joint un-evenness and warpage. Here again, a good quality mating surface can be made by applying copper or aluminium tapes, which create a good conductive area for local shielding or contact points. • Metal braid, mesh-type gaskets provide higher shielding, at the upper side of the required SE range. • Finally, if even more hardening is necessary, the ultimate solution is shown in Fig. 9, the most efficient since 100% of the seam becomes a very good conductive joint. Besides its cost, it adds the need for a strong locking mechanism to ensure good, even pressure on all spring blades. This method is applicable to both rotating (hinged) or slide-mating surfaces. It is extremely rare that such extreme solution be needed just for ESD requirements. Independently of bonding, a reduction of the slot leakage can be obtained, at pratically no cost, by designing the cover edges so that they always offer a generous overlap. This acts by providing an attenuation known as waveguide-beyond-cutoff.

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.. ............ Metal mesh on elastomer core

Extrusion mounting strip

Rubber gasket and adhesive backing

Metal mesh (monel, copper or aluminium)

ded. For cosmetic and mechanical abrasion reasons, the conductive film is generally on the box inner side.This may also prevent any possibility of direct discharge, such as the equipment will be submitted essentially to IESD, while keeping the benefit of a shielded envelope. One exception is electroless or electroplating, for which the nickel or chrome plating is an aesthetic, hard surface that can be on the outer side. In this case, DESD will apply. Some problems, though, are specific to metallized plastics: a) If a conductive coating is relied upon to provide an overall shield,

it must provide electrical continuity at the mating surfaces: top cover-to-base, side panels etc... With a plastic product, a continuous gasketing is sometimes expensive, so an alternative is to use tight tolerances for the mating faces, by designing a cross section that provides naturally a contact pressure (Fig 10). Make sure that the conductive coating extends: – Deep enough over tongue-and-groove side to make a positive contact. – But not beyond the groove center line, because this would permit direct ESD arcing in some areas that were not arc-reachable before. b) Use a paint or coating having good adhesion and resistance to abrasion, for a reasonable number of closures and frictions of the mating edges. c) If, thanks to its plastic enclosure, a product was declared as “class II” with respect to electrical safety categories (for inst. IEC Standard 435), one should verify that the metallization does not turn it into a “class I” isolation device.

Conductive elastomer extrusion (hollow tube)

Except for these particular aspects, all that has been said for metal housings (slots, seams, bonding, etc.) applies to metallized plastic as well. Surface conductivity can also be improved locally by using copper tape. Upper cover

Fig. 8. Compressible conductive gaskets and grounding “buttons” (right) from Chomerics Div. of Parker Hannifin Corp).

Conductive coating Plated area or riveted stripes

Watch for the overlap

Bottom envelope

Fig. 10. Abutting parts with metallized plastics. Tongue-and-groove design creates a labyrinth against ESD arc.

Fig. 9. Fingerstocks, the ultimate solution for more than 40 dB hardening. Partial (left) or total grounding with spring fingers

4.3 How to make shield barrier with plastic housings Plastic housings provide no shielding whatsoever, so unless the PCBs and internal wiring can withstand by themselves the ESD threat (in that case, an IESD), the plastic must be made conductive. Several metallizing processes exist. As discussed before, conductive coatings exhibit a rather mediocre absorption loss, and they work mostly by reflection. If a 30-40 dB SE range is desired, especially against low impedance sources like furniture/machine ESD, a conductive process with 1Ω / square or less must be selected. Another process, the particles-loaded plastic creates a volumic conductivity by inclusion of thin filaments or particles, providing absorption instead of reflection loss. Hovever the lack of surface conductivity complicates the bonding of metallic parts to the box skin, and it allows direct discharges, with multiple, cascaded arcing through the plastic barrier. With a close look at the box design, some features of plastic housing can be turned into an advantage against ESD, and pitfalls can be avoi-

4.4 Treatment of Shield Openings Besides the joints and seams, several large holes may exist in the housing for Displays, Cooling, Cables penetrations, Fluid penetrations, Components shafts, etc... They create shield discontinuities with the same leaky properties as seams. In strict terms of EMI, they should be treated to provide SE performance equal to or better than the one required for the whole box. However, ESD bears some specifics. It is rather unlikely that people will discharge frequently near a display window or a cooling aperture. Yet, if the packaging is such that likely discharge points exist near these functional apertures and vulnerable circuits are located right behind , then apertures should be treated with wire mesh, conductive glass, etc... or a good sink path must be provided for the discharge current to flow on the box skin, not reaching the inner parts. Toggle switches, LEDs and all indicator lights are another breech in the housing. Although feasible in sophisticated military equipment for instance, shielding a LED or small light bulb is cumbersome. A simpler approach consist in merely increase the breakdown voltage by adding an insulating, transparent lens which can resist to 15kV or more, depending on the ESD constraints (Fig. 11). Cables penetrations will be addressed in forthcoming Sect. 5.5, since the cable shield (if any) termination at the housing entry is a key factor in ESD immunity.

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Grounding clip

PCB

Insulating cap

• For plastic housings, – apply conductive coating with ≤ 1Ω/sq surface resistance, then treat like a metal housing. – avoid long screws protruding inside. – try to take advantage of air-gap and plastic thickness ( works for you at no cost)

IESD

Metallic front panel

• Respect shield integrity at cable entry points

Fig. 11. ESD penetration via PCB-mounted toggle switch. Solutions shown are a grounding spring that divert the ESD current on the front panel, or a 15kV- isolated toggle cap.

4.5 Non-Metallized Plastic Boxes Conductive plastics, that is merely turning a plastic skin into a conductive one, can be treated it like a metal enclosure. However, an electronic equipment does not necessary have to be put in a conductive shell to resist ESD. Carefully designed PCBs and well decoupled I/O ports can allow a product to function trouble-free under all but the highest ESD threats, like IEC severity levels 1, 2 and 3. The key to the success, in this case is to make sure that only IESD can happen, and no direct arcing can reach a critical part inside. This implies: • using exclusively discharge-proof, non conductive shafts, toggles, indicators etc.. with a sufficient dielectric strength to resist against a D-ESD. • keeping away from the openings (cooling, seams, assembly joints etc..) any active component, bare wire/trace or internal metallic part that could be reached by arc. This applies to obvious parts like magnetic or laser heads, discrete transistors or ICs metal cans, etc... but also to passive elements like internal brackets, screws and the like. Use a minimum 1mm/kV as a clearance rule. The creeping capability of an ESD arc is amazing, and even reasonably tight abutting joints can still allow an arc sneaking inside the box. If such clearance is impossible to insure for the highest ESD voltages, use a labyrinth design for the openings (Fig. 12).

ESD

ESD

SUMMARY of ESD Protection Measures at Mechanical Packaging & Box level • For metal housings, – Bond together every metal part (floating items are candidates for re-radiation) – Avoid long seams and slots: a 10cm empty seam is leaky at upper frequencies of ESD. Break them into smaller slots, or use conductive gaskets and waveguide beyond cut-off effect.

• Parts location inside – locate more sensitive subassemblies and wiring deep inside, far from housing surface and openings – locate less sensitive elements outboard from the above, acting as passive barriers 5. ESD PROTECTION OF EXTERNAL CABLES AND I/O PORTS External cabling are a greater problem. Due to their direct illumination during ESD, they become unintentional, but efficient antennas, converting the radiated field into induced voltages and currents. Fig. 13 shows what is happening to external cables during an ESD event. To combat the effects of this coupling, two approaches are available, which depend on the nature of the external cables and of the equipment enclosure. If the external cables are shielded (maybe for other EMC reasons, and probably not just against ESD), they will perform efficiently against ESD, provided some precautions are taken, the same as those used for good RF shielding results. If the system external cables are not normally planned to be shielded, and the equipment box is eventually plastic, there is no sense in shielding them for meeting an ESD immunity level. In this case, the ESD-induced pulses could penetrate the equipment by the external cables conductors, and they must be filtered, or eventually clamped, at the cable entry port. ESD

A

B

2 1

1

2

Cooling vents

C

Arc-reachable parts PCB Plastic

Plastic

Fig. 13. Role of external cables in the ESD coupling. (1) pictures the local ESD field inducing CM and DM currents in the cabling. (2) is the direct conduction of the Discharge current closing back to ground via the exposed cables. Notice that if equipments A,B,C are from different brands, the system level susceptibility can be as bad as the weakest of the ESD level.

Staggered spots

Fig. 12. Non-conductive plastic covers design for better ESD immunity. Internal metallic parts reachable by an arc can be protected by artificially increasing the path length (bottom sketch).

26

5.1 External Cables Shielding Although all cables are potential ESD coupling vectors, flat-cables come on top of the list because they are generally untwisted, unshielded and terminate on plastic connectors right on PCB inputs. They also offer a larger, more even stray capacitance to ground than multipair cables for instance, where wire pairs are convoluting randomly into the bundle. In a well documented set of experiments, C.Palmgreen (Ref. 6) has measured the voltage induced in flat cables by an ESD applied to the box

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where these cables were connected. From these tests, it is clear that for best ESD immunity, sensitive signals should use the central conductors of a shielded flat cable. Care should be taken to minimize the shield resistance by a) using cables with highly conductive shields; and b) providing low resistance, 360º shield contact to equipment frame. Unshielded and ground-plane cables provide no or little ESD protection.

A

B

Metallic ”target” box

Shielded cabinet

Shield connected to gnd pin inside the connector

Shield connected to chassis via short strap + screw

ESD simulator

Oscilloscope

100Ώ R=Zo

C 400 pF

ESD test Run/Fail level

Filter

Flat cable under test

HV source 5 to 15 kV

Connector under test

Dielectric

A

1800 V

B

4000 V

Metallic backshell 360º contact

C 10 kV

3365

Fig. 15. A practical case of shield termination influence on ESD susceptibility. The Conductors Dielectric

Cable (L = 2 m)

3469 3365 unsshielded

Ground plane

Edge

Center

> 500

> 500

3469 ground plane

150

40

EXP: full shield

0.4

0,2

3517

Jacket Cable

Voltage induced by 10 kV ESD (volts) on conductor

EXP

Shield

Fig. 14. Test set-up for measuring ESD-induced noise into flat cables. Table indicates the noise pick-up by 2 meters of various flat cable types, for 10kV ESD (Ref. 8)

With ESD, the empirical recipes about cable shields ( ”thou will ground the shield at one end only to avoid ground loops...”), which can be justified at audio or low frequencies, are irrelevant. To reduce ESD pick-up, a cable shield must be bonded to each housing that it penetrates. The argument that a floated shield will not allow the ESD current to flow and, therefore, will avoid coupling, does not stand a thorough analysis, nor the practical experience. The shield floated end reaches several hundred volts of CM voltage and will re-inject some of it by capacitive couping onto the inner wiring. One useful figure of merit is the shield transfer impedance, Zt. If a cable exposed to ESD is of the coaxial type, the noise appears due to the ESD-induced current coupling via the transfer impedance of the braid. (Details in Article , EE Magazine 2.2016). Since it provides the transition between the cable shield and the machine envelope, the bonding of cable shield to machine frame interacts with the box shield integrity addressed in former section. A most direct bonding of the cable shield to the outer skin of the equipment box will prevent the ESD currents carried by the shield from re-radiating inside. An example of this is seen on Fig. 15 with the drastic improvement when a good shield-to-box metallic contact is achieved.

mediocre result of config. A is due to to the pick-up of the ESD field by the stripped segment of the braided shield, the ESD current carried into the machine by the long grounding wire and the heavy pin-to-pin crosstalk from the gnd wire inside the connector itself.

Ferrites toroids, “the poor man’s shield”. A ferrite toroid over an external cable cannot match the the 40-60dB attenuation of a real, good braided cable shield. However, although this bulge on the cable looks more as a desperate last minute fix, it provides 6 to 12dB reduction of the ESD coupling to the cable, which may be enough in some cases, for a solution that is inexpensive and easy to add on an existing cable without any hardware change. 5.2 ESD hardening of I/O Ports In many applications, external cables are unshielded, and must remain so. Therefore, wether the box is metallic or not, the penetration of ESD-contamined wires inside the equipment is a serious threat, which must be controlled at the point of entry. This dictates that filters or transient voltage suppressors (TVS) be placed at the connector receptacle itself, or the nearest PCB area. When an I/O port receives unshielded cables, two cases have to be considered: • No direct discharge (contact or arc) can access the terminals pins, or screws etc... Therefore only induced pulses, whose duration does not exceed few ns can penetrate the equipment. A filter with a good attenuation above ≈ 30MHz is generally sufficient. • The terminals are exposed to both induction coupling as above, plus incidental direct ESD, where the full ESD pulse could be injected into I/0 circuits. In this case, filtering is needed for error-free response to the short pulses, and TVS are a must for a no-damage criteria because of the longer pulse (50-100ns) a) Filtering short ESD induced pulses Simplest filtering is made by low value ceramic capacitors, preferably leadless (SMT) type. If leaded, they must be trimmed to the shortest possible length (Fig. 16). A 800pF disk capacitor with just 2 x 2 mm lead length starts loosing its efficiency at 100MHz, to become useless above 300MHz. Filtered connectors for through-panel or PCB mounting are very efficient above few tens of MHz, that is the bulk of ESD frequency spectrum. For the expensive types, each pin is constructed as a “Pi” or “T’ filter, giving a substantial attenuation in the VHF range (30 -300MHz). Cheaper models use miniature SMT capacitors mounted in the receptacle. They exist for most usual connector styles (Sub-D, Micro-D, USB, IEEE-1394, Ethernet/ RJ45 etc... ). For PCB mounting, if the size, weight or cost of filtered connectors are prohibitive, economical substitutes can be made with surface-mount capacitors or planar arrays, close from the connector footprint (Fig. 17). Each incoming trace is decoupled to the PCB 0v Ref., or better to a chassis-connected copper land, with maximum precautions to avoid parasitic inductances. However, this is only a one-pole (20dB per decade) attenuation, so if the cut-off frequency requirement imposed by the I/O signal bandwidth is too high, say 100 MHz for instance, it will provide barely a 3 times (10dB) reduction at 300MHz. This may not be enough

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for an error-free objective against a 10 to 100V induced ESD spike. D Connector mounting flange

The amount of capacitance must be compatible with the bandwidth necessary for the useful signal carried on each line. These capacitors will be preferrably mounted in a common-mode arrangement, decoupling each trace to chassis ground. With differential or isolated inputs, if a capacitor C is decoupling each line to chassis, the incoming differential pair will see a capacitance C/2 .To get the full benefit from these decoupling devices, follow these simple rules:

Ceramic array

1

6

Detail o MLC stack

• Compute the maximum capacitance tolerable w/o signal distorsion • Connect all the ground terminals of the capacitors (or arrays) to a copper land surrounding the connector area. Even with PCB 0V-ref grounded to chassis, this land should be preferably distinct from the 0volt plane, and directly connected to the nearest chassis point. As result, the ESD currents diverted by the filter will sink to the frame ground with minimum disturbance on the board. • Keep these capacitors tolerances tight if they are used on true differential lines. This prevent the risk of C.M. conversion by capacitive unbalance, not only for ESD but for all RF emission /immunity aspects. • Check for the surge voltage withstanding capability of the capacitors. In some environments, they must survive kV surges like for the Class-Y capacitors used in AC mains filters. This is especially true with isolated inputs, or PCBs with floating signal reference. • Make sure that all I/O lines have been decoupled in the same zone. One single line (even a dormant one) left unfiltered can couple with the others.

Ceramic capacitor (short leads) Between O V and frame ground “Frame ground”

Fig. 17. Instead of individual capacitors, multilayer capacitor arrasy can filter all the lines at once. If the designer wishes its PCB zero Volt isolated from chassis, a discrete 10nF ceramic can be inserted in-between.

For computing the maximum value of tolerable capacitive filtering, Fig. 18 . shows that, to avoid degrading a useful signal having a necessary bandwidth F max, we must keep: 2.Xc >> RT with Xc = impedance of one capacitor at frequency Fmax RT = total impedance of victim Rload//Rsource, or Rload // Z0 (charact. Impedance for a long line) For a good pulse integrity (distorsion barely perceptibe), this condition is shown on Table 5.4, calculated for some typical digital data pulses.

PCB ground plane

Leaded version

Interrupted Common traces ground land dB

Leadless capacitors version

Three-terminal feedthrough SMT

Version:

Low-speed CMOS interface (typ.)

TTL

HC/AC, fast LVD

tr Bwidth Z* Cmax for good pulse integrity C max for marginal pulse distorsion

0.5 - 1µs 300kHz 120Ω 2200pF

50-100ns 3MHz 3-500Ω 150pF

10ns 30MHz 100Ω 30pF

3.5 - 1.5ns 100-230MHz 50Ω 15pF

6800pF

430pF

100pF

33pF

Z*: differential impedance = Rload//Rsource, or Rload// Z0

Table 5.4 Maximum Comm. Mode capacitors values for VHF and ESD decoupling

Attén. in 50 Ω

50 40 20

820 pF surf. mount L total = 1,2 nH

10 0

1 MHz

10 MHz

Useful signal:

Feedthrough 820 pF

820 pF disc Leads 2 mm L total = 5 nH

30

100 MHz

1 GHz

Z0 Characteristic impedance

F

Fig. 16. Simple ceramic capacitosr filtering near PCB I/O connector. A wide common ground copper land or plane is a must. Bottom: Attenuations with single capacitor filtering: leaded, SMT and feed-thru (given for a 50Ω/50Ω test configuration).

28

Type of signal

c c

Rc

OK Too much capacitance

Fig. 18. Configuration of Comm. Mode capacitors for VHF and ESD decoupling, and maximum tolerable values.

Steeper attenuations are obtained at PCB level with inexpensive “T” filters made of 3-lead ceramic capacitors and small ferrite beads. Such components are available in leaded or surface-mount versions. The “100pF/100Ω” rule-of-thumb, often used by EMC practioners for standard EMI reduction above 30MHz, suits ESD as well. It means that a 100pF capacitor on the high impedance side, looking toward an analog or digital input, combined with a 100Ω series resistance (or a ferrite with≥ 100Ω impedance) will solve most RF immunity, emission and ESD problems. This results from the following, simple observation:

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• no matter the actual load (victim’s side) impedance, provided it is ≥ 100Ω, and • no matter the actual source (line side) impedance, A 100pF/100Ω team will always provide, at least, an attenuation of: –10dB @ 50MHz, 20dB @ 150MHz, 30dB @ 500MHz (actually, 24dB Insertion Loss) For a single pulse, like ESD, this translate as a 10 times amplitude reduction (notice that the attenuation of a filter for an isolated pulse is less than that with a single frequency).

CAPACITORS

FERRITES

• Efficient attenuation with high impedance circuits (Rs and RL ≥100Ω). Up to 40dB with SMT parts)

• Modest attenuation, generally 6-16dB in typ. applications. Work best in low impedance circuits (Rs and RL ≤100Ω)

• Can affect symmetry with balanced differential inputs

• No impact on line symmetry

• Values restricted to what the useful signal can tolerate across the line. Generally 30 to 300pF for digital inputs

• Do not affect useful signal, if CM-mounted • Easy to install, no or minimum hardware changes.

Varistors or Zener have significant intrinsic capacitance (typically few hundreds of pF) providing a filtering of the short pulses, at no additional cost. However, if the protected line is a high speed digital link or an RF input, this capacitance would bring too much distorsion. Special TVS modules are available with very low capacitance, like 5pF for High Speed Ethernet, or high definition video (Fig. 20). A few manufacturers have developed combinations of TVS + filter + single or balanced terminating resistors in a same integrated package, capable of protecting 2 to 10 lines. Other TVS ( by SMT or Littelfuse Inc.) are based on crowbar principle, where a thyristor is triggered, shorting the line to ground when its voltage exceeds the supply dc voltage. Flexible TVS membrane for connector sockets are available, for quick fix. A cheap D-ESD protection can also be made with gas-tubes or airgaps. They are robust devices, but their firing accuracy and response time for a nsec. pulse front is mediocre, so they fit only for the less fragile applications. A rough overvoltage suppressor can be made by a 0.1 to 0.2 mm gap on PCB traces, firing approximately at 1- 2kV. Such devices should never be used on low impedance dc lines: the arc would not extinguish since it remains fed by the dc source.

Low capacitance transient suppressor

Table 5. Selection criteria for ESD & short pulses decoupling (Rs, RL = source & load side)

For last minute hardening, or when deep PCBs or hardware changes cannot be made, add-on parts can be used: – The flexible insert filter of Fig.19 is manually fitted into an existing socket, turning an ordinary connector into a capacitive filter. Small tabs on the membrane edges allow a peripheral grounding to the metallic receptacle. – Filtered Connector sockets exist for most standard connector types. The Male/Female filter adapter is a quick-fix version to be inserted between the two parts of an existing connector, without any hardware change. Like for the membrane-type, the existing receptacle should have a grounded, metallic shell. Filter insert for 9-pin D-subs

Voltage rating

100 470 1000 1500 2000 4700 10000

200VDC 200VDC 200VDC 200VDC 100VDC 50VDC 50VDC

Data –

P.down GND

Combined low-capacitance TVS and EMI filter for highspeed differential signals.

with full ESD protection (source: ST Micro).

c) Accessible pins of unused connectors

Filter wafer features: ● Low-cost, high performance alternative ● Available in all standard and high density D-sub configurations ● Also available for MIL-C-38999 and MIL-C-26482 and other connectors ● Fits completely and unobtrusively inside mated connectors

Data +

Fig. 20. TVS modules for hi-speed signals. Lower sketch combines HF noise filter

Standard capacitances Capacitance (pF) @ 1kHZ

+Vcc P.up

Equivalent circuit for each pin Discrete capacitor Connector shell

Fig. 19. Flexible membrane capacitive filter array (Courtesy of µM-Microelectronics Mfg.)

b) Transient Voltage Suppressors against direct discharges on I/O ter-

minals Direct ESD can inject the full energy of a discharge into those circuits which are wired to accessible parts of the equipment. Such inputs, especially ICs, have a normal ESD immunity generally in the 2-4kV range (Re. Sect. 1, IC Protection). So, unless special ESD-hardened ICs have been selected, they must be protected by fast TVS.

Depending on the equipment configuration and the type or number of interconnected units, some connector sockets could be left without cables. But if the inner wiring of the electronics is installed, these unemployed connectors are an invitation to serious ESD problem if they are accessible. A bare pin approached by a finger at less than 1 cm or so, can convey a direct ESD straight into sensitive components. Although some specifications are exempting these connectors from a contact or air-discharge test, it is recommended that such event be considered, at least as a no-damage criteria. Several solutions can be used: • Do not install the inner wiring when the corresponding option is not present on this model • Mount the socket in a recessed area, so that a charged finger or handheld tool will zap the housing or connector edge first, • Place a metal cap or blinder on un-used connectors, • Place a plastic cap or blinder on un-used connectors, with a breakdown voltage > 20kV • Protect the corresponding lines with TVS ( not needed if the bare receptacle is not exposed). • Use a simple mechanical shorting device, with a spring blade that grounds all the pins to the metallic receptacle rim when the connector is not there. d) Opto-electronics as an ESD barrier

Opto-electronics often viewed as the panacea against EMI, would seem

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to be an ideal solution against ESD as well. Although they must not be rejected a-priori, they may give disappointing results: • Optical Isolators (OI) have parasitic input-to-output capacitances that can represent 1 to 5pF, once mounted. For an ESD rise time in the nanosecond range, this is practically by-passing the isolation barrier by less than 1kΩ. Also, an OI can be activated by dV/dt ranging from 10V/µs for the cheaper parts to few kV/µs for the best ones. ESD transient reaching PCB traces easily exceed 10V/ns, triggering most OI except the High Immunity ones. • Fiber Optics (FO) are certainly a better solution. But the designer is not exempted from carefully shielding and/or decoupling the detector end of the FO link. e) Preventing ESD back-door entry by the power cord

Power cords are often overlooked in their contribution to ESD coupling, because they connect to transformer or other bulky, robust components. However, as it penetrates the machine enclosure, a power cord may carry to the inside the transients induced by ESD. Here, the solution resides in filtering/decoupling the power cord right at its point of entry. Since power cords are filtered anyway, this seems superfluous; but most RFI filters are optimized to meet conducted specifications below 30 MHz and may be inefficient in the >100 MHz range of ESD. In this case, the filter can be improved by additional ferrites, or mounted in a way that preserve its input-to-output isolation. Another solution, not mutually exclusive, is to use a shielded power cord, that will both prevent ESD re-entry and improve the drain path to ground. 5.3 I/O Cable ESD hardening with plastic products If a product has a total plastic enclosure, with no conductive treatment, and the designer is confident that he can still meet the other EMC requirements (Radiated Emission limits, etc...) it would be regrettable to be forced to a metallization just for ESD. At least it is worth trying a design pass without it. So we are left with I/O cables which are either: Shielded, with no chassis for connecting the shield, or unshielded. For shielded cables, although an all-plastic box make their use questionable, several solutions exist (Fig. 21): • Connect the shield(s) to the PCB 0Volt Reference. This is the less desireable option, because ESD currents drained by the shield will spread accross the signal reference. • Connect the shield to an artificial ground (Fig. 21 , bottom). This is a piece of metal foil or conductive coating, with at least a 50 cm2 area (with 100 cm 2 being preferred), laid in the plastic housing, bottom side. Placed near the I/O entry points, this foil will collect the shield currents (instead of the 0V plane) and spread them to ground via the foil stray capacitance. Ideally, the cables shields should physically connect to this foil with a 360° joint. This is seldom practical, so the cable shields can be terminated on the PCB by a metallic connector housing, or clamp, then bonded to the artificial ground by a wide strap or bracket. The shield connection on the board should be a dedicated copper land, preferably not the 0V plane. With unshielded cables, the principle is to clean-up the wires of their ESD-induced noise before it contaminates the PCB. So HF decoupling will be used (see sect. 5.2, PCB), with the decoupling capacitors connected following the same rules as cable shields above: • Connect the decoupling capacitors to the PCB 0Volt plane. This, too, is the less desirable option because it contaminates the signal reference (Fig. 21 top). • Connect the capacitors to an artificial ground, made by a metal foil in the I/O ports area, not extending too far underneath the board (Fig. 21, bottom).

30

Lack of any better: to the PC board 0V plane Problem: ESD current is spred in a functional reference

0V 0V

0V

Better: Gather all these connections in the same PCB area

shields and decoupling capacitors connection

Even better: Mettalize (conductive paint, copper tape, etc...) a limited area of the bottom cover: will act as an artificial HF ground

I/O signal traces

PC board

Even better: do not extend this land far under the board or in ”touchable” zones

Fig. 21. Where to connect filters and cable shields ? Treatment of external cables entries with non-conductive plastic boxes.

6. ESD IMMUNITY BY SOFTWARE AND NOISE INHIBITION TECHNIQUES ESD is generally an isolated, elusive event happening at worst no more than a few tens times a day, a few weeks per year. Therefore, software/firmware error detection and correction can be simpler and less expensive than adding components. The following few guidelines (some inspired by the excellent analysis of Ref. 8) can help to implement this “intelligent filtering”. However, one must remember that: a) Nothing is free and the added instructions for “catch-all” error recovery increase the program size. Memory space can double, and execution time (cycles) can be multiplied by 1.5 b) A lot of software traps are camouflages simply patching a more general vulnerability to all kinds of electromagnetic disturbances, not just ESD. Non-damaging, low level ESD-induced pulses can cause severe errors and machine lock-up. Appearing on critical Processor/ Controller lines, like : Oscillator inputs, Reset, Interrupt Request, or also chip resident programming or manufacturing customization or debugger, they could corrupt or freeze a program execution. Several defensive software techniques, often embedded in the µProcessor itself, can be used : • Software deglitchers (voting or polling techniques) to confirm the status of an input, using multiple reading • Error-detection methods like parity check, CRC check, HDLC, digital filtering, auto-correlation and ... etc • Program run-away, detected by checking the time duration of routines, avoiding non-intentional executions • Regular, periodic programmed refresh, even without special aberration detection The I/O management connecting the processor to sensors, actuators or communication devices can periodically refresh the I/O port register to prevent any illicit change. For analog inputs, a regular check against a min/max range, based on history of a previous of values, will ignore an instantaneous value that is suddenly out-of range. Many of these techniques are associated with dedicated safeguard circuit like the Watchdog, built-in the IC. The CPU generates a periodic signal as long as everything is okay. If not, a recovery is initiated (“deadman’s” detection technique). If the main program is stuck in a frozzen state, the watchdog will Reset/Restart the processor. This is often undetected by the user, hence tolerable. But in some cases, the reset is suspending the regular operation, becoming a nuisance. Or, if the Watchdog signal itself is triggered by an ESD, the scheme is defeated, and un-ne-

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cessary restart will occur. For this reason, some test plans require that up to a certain ESD voltage, the EUT should make no error at all, even recoverable; reason being that such low voltage ESD occurences can be very frequent in some environments. A leading idea for ESD hardening with firmware is mistrust: one should never assume that the state of an I/O port, register, memory address etc ... has not changed since its last legitimate use. If an undesired change in the status of a line can trigger a wrong sequence, this line should be periodically refreshed, or checked/ restored. This should be used only for serious cases, like when the sequence of events would end in a lockup, requiring operator action. Fault-tolerant architectures and “graceful recovery” require that the designer knows all kinds of output states that can legally exist . Concerning data lines in general: • No circuit should be authorized to disable itself for an undefined period. • Critical inputs, especially those which can trigger an irreversible sequence, should be checked twice. • Make an “And” gating of critical signals with an undisturbed clock line. For instance, a RAM can be selfprotected against an illegal WRITE through an extended addressing; But if an ESD induces a same pulse on both the “Read/Write” and the “Enable” inputs, the protection is defeated. Nevertheless, as said at the beginning, solving ESD problems by software tricks is basically “cheating”. Some other severe high frequency threats, like the exposure to strong RF fields (10V/m or more) and Electrical Fast transients with kV peak may exist which the software cannot handle. Their interference will be either quasi-continuous (with RF fields), or so recurrent (EFT means bursts of 50 pulses/sec) that autorecovery simply cannot work. The sofware will keep trying to restart a machine that is making errors over errors. Therefore, software defense has to remain the last barrier for rare, isolated events, not exonerating the designer to apply all hardware techniques described in this chapter. 7. ESD IMMUNITY WITH MINIATURE, PORTABLE DEVICES An increasing number of small, hand-held or pocket-size devices are carried by a huge number of people. Just to name a few of these “nomads”, on a list which is extending every month: cellular phones and related accessories, palm-size personal agendas, low power wireless (Bluetooth etc..) devices like wireless mouses, USBs transceivers, USB keys, miniature FM radios, music players/recorders, RFID, some devices being body-implanted (cardiac peacemakers, hearing aids, insuline dispensers), smart car keys, GPS road maps etc ...Regarding ESD, all of these share in common some remarkable features: • They are light, plastic-encased, packed with complex electronics, often combining audio input/output, RF transceiver, hi-speed digital processing, optical sensors and image processing with small LCD or O-LED displays • Some incorporate one or more miniature RF antennas • They are constantly touched, carried or manipulated by people, therefore in nearest proximity of notorious ESD carriers: human skin and clothes, eventually car seats/upholstery • They often have accessible, subminiature I/O connectors. So they appear as first class targets for severe I-ESD and D-ESD. Fortunately, several factors counterbalance these pessimistic expectations. Their size, generally no more than the palm of a hand and often less, result in very small exposed circuit loops and stray capacitance, with traces length not exceeding a few cm. Also, for obvious reasons, designers had to take serious precautions to preserve at once low RF emissions, high RF immunity and mutual compatibility of many internal functions packed into such small space. For instance, the PCB host for the active circuitry, generally a single miniature board, also acts as the supporting structure for integral or segmented shields, because the device’s plastic housing is just a physical shell without shielding. This PCB is a multilayer type, with the gnd plane frequently connected with ICs internal ground planes (see Sect. 2.3). The first layer (component face) has copper lands for soldering small metal covers with grounding tabs on the four sides. The device plastic shells can be assembled together by a seamless

process (ultrasonic welding, for inst.), such as the final casing is hermetic to arc discharge. Miniature connector sockets have a metallic housing grounded to the PCB, making it impossible to approach a charged finger without arcing on the metal edge first. For reducing the risk of a charged cable to discharge on sensitive pins at plug-in, these connectors can have a peripheral ground ring or sleeve that makes contact first. Miniature RF antennas are patch type which are not touchable. If a risk of air discharge remain at 15kV, miniature TVS with low parasitic capacitance and VSWR can be mounted on the antenna feeder trace. Same technique is applied to microphone inputs. Thanks to these advantges and along with many other tricks, most of these nomad devices have a remarkable immunity. USB keys can resist to more than 10kV/m of RF field up to a GHz, with burst duration of 100ns, which is a more intense exposure than any closest ESD. Cellular phones do resist to the IEC 8kV contact and 15kV air discharges. Contactless car keys are generally damage-free (or code-erase free) up to 25kV, per ISO 10605. 8. ESD CONTROL AT INSTALLATION LEVEL Installation environment is an aspect on which the designer has little control. Furthermore, since equipments are generally specified for certain environmental conditions, it would be foul-play to change the environment because an electronic device does not meet the challenge! Yet, life seldom provides clear situations like this. Many times the environment was not or poorly defined at the time of initial design, or salesmen might have overdone it and sold an equipment for an environment where it should not have been installed. So, if everything else fails or at least to provide temporary relief waiting for a more engineered solution, the following can be done: • Maintain relative humidity above 50%, or use and ionized air blower. • install a grounded metallic rail, that everybody will touch when approaching the system • Use anti-static spray. Anti-static properties remain for about 2-4 months, depending on traffic. This does not bleed-off existing charges, but avoid static generation • Use seat pads in nearby chairs having breather-type fabrics. • Ground the chairs (or carts) by using conductive wheels • Avoid carpet around system, use carpet with grounded woven metal thread, or cover the carpet with anti-static slightly conductive mats Floor conductivity has been a long-time concern in the electronics industry and industrial buildings in general. For instance, electrical resistance should meet NFPA Bulletin 56A issued by the US Natl Fire Protection Assoc. or, in Europe, DIN Std n°51953 & 53482 (Concentric electrode test). NFPA standard recommend a 25kΩ to1MΩ resistance of the installed floor, between two electrodes 1 meter apart. Another test often quoted is the “standard pedestrian”, where a person charged to 5kV walks lifting or shuffling his shoes on the specimen. Carpet is declared as conform if the residual voltage is < 2 kV within 2 seconds. The parameters for anti-static flooring are: a) Surface resistivity (Ω/sq.) relates to the propensity to static charging and retention. It does not necessarily mean that this carpet can “ground” an already charged person or furniture. b) Transverse resistivity (Ω-cm) relates to volume resistivity i.e. the charge sink to ground. Anti-static floors must be installed properly, or treated later with certain cleaning impregnations. The anti-static carpet on Fig. 22 applied with a very insulating glue, may not generate static charges, per se, but cannot sink to ground the charges brought into the room by someone coming from outside. For this reason, anti-static (in fact static-disspative) carpets incorporating a % of metal or carbon fibers in the yarn should be electrically connected to the room earthing conductor. Floor tiles and desk overlays usin an internal carbon filler (Rs ≈ 105-107 Ω/sq.) should be grounded via a permanently contact to this layer.

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Fig. 22 Top: Floors surface resistivity versus RH. Bottom: A typical charge decay)

1011

Insulating floor (silicon waxed floor, vinyl tiles, nylon carpet, etc...)

Wool carpet

109

Surface resist. Ω/sq

of anti-static carpet. Below: such carpet can become useless if insulating glue is used, turning the carpet into the charged armature of a capacitor.

· ········-

1013

Typical computer room anti-static carpet

-

107

REFERENCES & SHORT BIBLIOGRAPHY [1] Sicard,E, Bendhia, S, Baffreau, S, Ramdani, M.“EMC of Integrated Circuits” Springer, 2006 [2] Mardiguian, M. ESD, Understand, simulate and Fix, Wiley, IEEE Publ. 3rd edition, 2009 [3] Ming Dou,K. IEEE EMC Transactions , Feb.2008 [4] White, D.R.J., Mardiguian,M.“ Electromagnetic Shielding” Vol.3 EMC Handbook Series, 1988 [5] Ott, H. “Noise Reduction techniques in Electronic Systems” Wiley Interscience. [6] Palmgreen, C. “Shielded flat cables for EMI/ESD reduction”, IEEE/EMC Sympos.,Boulder, 1981 [7] Boxleitner, W.”ESD and Electronic Equipment” IEEE Press [8] King, M. “Mastering ESD System response”. EMC Technology Magazine, March & May 1988

Rel. humidity 10%

Initial voltage

30%

Anti-static carpet (R>107Ω)

50% point 2.2kV

0.6 sec

Michel Mardiguian EMC Consultant, France m.mardiguian@orange.fr

Final voltage

7.6kV

32

50%

2.1kV 1.4kV Concrete slab

Insulating glue (R>1011Ω)

www.electronic.nu – Electronic Environment online


Electronic Environment #3.2018

Branschnytt

Ny internationell standard för IoT

Miltronic blir LAPP!

NU FINNS BESKRIVNING av vad sakernas internet – internet of things eller IoT – är för något och hur det hänger ihop: ISO/IEC 30141. Med den nya internationella standarden ISO/IEC 30141 finns nu en sammanhängande beskrivning – en referensarkitektur – för sakernas internet, framtagen i ett globalt samarbete. Standarden ger en referensarkitektur för IoT med hjälp av en uppsättning systemegenskaper, en begreppsmodel och en referensmodell. Referensarkitekturen ligger på en övergripande nivå och från den utgår de specifika modeller som behövs för olika sammanhang och uppgifter. Standarden anger också olika egenskaper för IoT-system och beskriver olika aspekter av referensarkitekturen.

MILTRONIC HAR VARIT ett helägt dotterbolag till tyska LAPP Group sedan 2008 men den 1 oktober 2018 byter företaget namn till LAPP. Namnbytet i Sverige är en del av den samordning av koncernens företagsnamn som genomförs över hela världen, då moderbolaget samlar alla dotterbolag under samma namn. Samarbetet med den tyska koncernen startade redan på 1970-talet, växte sig allt starkare och Miltronic blev slutligen ett dotterbolag 2008. – Namnbytet tydliggör att vi är en del av LAPP Group. Det ger våra kunder ökad tillgång till koncernen, till det stora utbudet av kvalitetsprodukter, omfattande produktutveckling och inte minst till de lokala bolagen över hela världen, skriver vd Krister Karlsson.

ISO/IEC 30141 är alltså ett grundläggande och teknikneutralt dokument som ska göra en sammanhängande uppsättning IoT-standarder möjlig och dessutom uppmuntra öppenhet och transparens vid implementeringen av IoT-system. ISO/IEC 30141 har tagits fram i ett arbete som drivs gemensamt av de båda internationella standardiseringsorganisationerna ISO och IEC och är baserad på resultat från olika organisationer, också från t ex IEEE, ETSI och 3GPP. Den svenska spegelkommittén SEK TK IoT organiseras av SEK Svensk Elstandard, läs mer om den och om ISO/IEC JTC 1 SC 41 på elstandard.se. KÄLLA: SEK Svensk Elstandard

Utlysning om standardisering VINNOVA HAR ÖPPNAT en utlysning för att ge stöd till projekt som beskriver förutsättningar för och behov av standardisering som kan stärka svensk innovation och konkurrenskraft inom områden med ny potential för standardisering. Utlysningen är kontinuerligt öppen fram till 1 februari 2019. Vinnova bedömer inkomna ansökningar vid tre tillfällen med avläsningsdatumen 2 oktober, 13 november och 1 februari. Utlysningen riktas till dem som har konkreta idéer om vad som skulle behöva göras för att avhjälpa problem kopplade till standardisering inom ett utpekat innovationsområde eller en bransch. Saknas standarder helt? Råder det brist på gemensamma begrepp? Är det svårt att få gehör för att utveckla existerande standarder så att nya innovativa produkter eller tjänster omfattas? Krockar regelverk från olika branscher eller områden? Har viktiga aktörer inte råd eller tid att delta på det sätt

som krävs av dagens standardiseringsprocess? Standardisering är en intressentdriven verksamhet. Idéer och förslag till nya eller förbättrade standarder kommer alltså från företag, myndigheter och andra som ser ett behov eller som upplevt ett – oftast – tekniskt problem som fordrar en gemensam lösning. Inom det elektrotekniska området bedrivs det allra mesta av arbetet i internationellt samarbete som organiseras av IEC. SEK Svensk Elstandard, www.elstandard.se, är den svenska medlemmen i IEC och möjliggör svenska intressenters medverkan i arbetet i IEC och i den europeiska motsvarigheten CENELEC. SEK är också utsedd som svensk standardiseringsorganisation av regeringen. Läs mer och ladda ner utlysningstexten från Vinnova på vinnova.se. KÄLLA: SEK Svensk Elstandard

33


Electronic Environment #3.2018

Noterat

”Fordonet är inte beroende av sin kaross för att kunna köras, utan tomma chassier kan köra till olika platser för att hämta rätt kaross för nästa jobb”

Självkörande koncept för gods och människor Mercedes-Benz senaste konceptbil är egentligen mer koncept än bil. Vision URBANETIC är ett system där eldrivna självkörande transporter av både människor och varor kan skötas av samma fordon. VISION URBANETIC, som Mercedes-Benz nyligen visade, är en helt ny lösning på framtidens transporter av både människor och gods. Målet är att gatorna ska ha färre fordon, mindre utsläpp och mindre buller. Samtidigt som det ska gå snabbare att ta sig fram. Grunden är ett självkörande eldrivet chassi som enkelt kan byta kaross. En 3,7 meter lång kaross får plats i det 5,14 meter långa fordonet. För passagerartransport rymmer den upp till 12 personer, och med godsmodul kan den lasta upp till tio EUR-pallar. I chassit finns IT-infrastrukturen som i realtid analyserar tillgång och efterfrågan på transporter i närområdet, och sedan planerar kör-

34

ning och ”karossbehov” efter detta. Systemet har tillgång till information från mängder av datakällor och vet till exempel om det varit ett event någonstans med människor som ska åka därifrån. Systemets nav får också reda på om ett existerande fordon känner av en folksamling någonstans, och flyttar då fler fordon dit. Det blir alltså en typ av kollektivtrafik som är helt oberoende av fasta rutter eller tidtabeller. Den som vill åka eller transportera något beställer helt enkelt en transport, och väntar på att den kommer. Detta gör också bland annat att problemen med kostnader för kollektivtrafik på landsbygden eller på obekväm arbetstid försvinner. Med lastmodulen på 10 m3 ryms upp till tio EUR-pallar i två plan som kan hantera B2Bdistribution till butiker i städer. Men det finns också helautomatiserade lastsystem som kan fungera som mobil utlämningsplats för paket eller matkassar till konsumenter. Fordonet är inte beroende av sin kaross för att kunna köras, utan tomma chassier kan köra till olika platser för att hämta rätt kaross för

www.electronic.nu – Electronic Environment online

nästa jobb.

 EN DEL TALAR om självkörande fordon som en utmaning för arbetsmarknaden, men faktum är att det kan vara tvärtom. I Tyskland utsågs ”Fahrermangel” (förarbrist) till årets logistik-ord 2017 och brist på förare är ett problem även i Sverige. Ju mer e-handel vi använder, desto större blir också behovet av sista-kilometern transport. Tillsammans blir detta ett stort problem både för handel och kunder. Med fordon som Vision URBANETIC kan chaufförer istället arbeta med mer avancerade transporter som kanske har krav på speciell lastning och lossning. Allt medan standardtransporter kan skötas automatiskt.

 Tack vare eldrift och att det inte behövs chaufförer kan fordonen vara igång dygnet runt, förutom vid service och laddning. I kombination med karossbytena gör det att antalet fordon i en stad vid varje givet tillfälle minskar – och därmed både trängsel, utsläpp och buller. Allt för att göra våra städers livsmiljö bättre.

 KÄLLA: Mercedes-Benz


Författare

Electronic Environment #3.2018

Författare – Electronic Environment Electronic Environment överbygger kunskap inom specifika elektronikområden – mellan myndigheter, högskola och universitet samt näringslivets aktörer. Det kan vi göra tack vare ett stort intresse och engagemang från många duktiga skribenter och deras organisationer. Sedan tidningens första utgåva 1994 har ett stort antal skribenter bidragit med sin kunskap, till mångas glädje och nytta. Här presenterar vi våra skribenter de senaste åren, och i vilka nummer du kan läsa deras bidrag. Ett stort tack till er alla som bidragit genom åren till tidningens utveckling! Dan Wallander / ansvarig utgivare

TEKNIKREDAKTÖRER Michel Mardiguian Teknikredaktör EMC Consultant 2/2015, 3/2015, 4/2015, 1/2016, 2/2016, 3/2016, 4/2016, 1/2017, 2/2017, 3/2017, 4/2017, 2/2018, 3/2018

Miklos Steiner Teknikredaktör Electronic Environment 4/2014, 1/2015, 2/2015, 3/2015, 4/2015, 1/2016, 2/2016, 3/2016, 4/2016, 1/2017, 2/2017, 3/2017, 4/2017, 1/2018, 2/2018, 3/2018

Peter Stenumgaard Teknikredaktör FOI – Swedish Defence Reasearch Agency

Christer Karlsson Ordf. Swedish Chapter IEEE EMC RISE 4/2014, 1/2015, 2/2015, 3/2015, 4/2015, 1/2016, 2/2016, 3/2016, 4/2016, 1/2017, 2/2017, 3/2017, 4/2017, 1/2018, 2/2018, 3/2018

4/2014, 1/2016, 3/2017

Dag Stranneby Campus Alfred Nobel, Örebro universitet

Jan Welinder RISE Elektronik

Daniel Eidenskog FOI – Swedish Defence Reasearch Agency 1/2018

FÖRFATTARE

Erling Pettersson STRI AB

Anders Larsson FOI – Swedish Defence Reasearch Agency

1/2016

1/2018

1/2018

1/2014

Giovanni Frezza Molex

Ann-Kristin Larsson Swedavia 1/2014

Anneli Waara Uppsala universitet 3/2014

Bengt Vallhagen Saab Aeronautics, Saab AB 3/2016

Björn Bergqvist Volvo Cars 4/2016, 3/2017

Björn Gabrielsson FOI – Swedish Defence Reasearch Agency

Joeri Koepp Rohde&Schwarz 3/2016

K G Lövstrand FMV T&E Karin Davidsson RISE Elektronik Karin Fors FOI – Swedish Defence Reasearch Agency Kia Wiklundh FOI – Swedish Defence Reasearch Agency 3/2014, 4/2014, 3/2015, 3/2016, 4/2016, 1/2017, 3/2017

2/2017

Göran Jansson Saab Bofors Testcenter 3/2014

Hartmut Berndt B.E.STAT European ESD competence centre, Germany

3/2014, 4/2015

1/2015, 1/2016

3/2015

Gunnar Englund GKE Elektronik AB

Henrik Olsson Elsäkerhetsverket

Jenny Skansen ABB Power Systems

3/2014, 4/2014, 1/2015

2/18

2/2014

3/2014

3/2015

Farzad Kamrani FOI – Swedish Defence Reasearch Agency

Anders Thulin ATC AB

3/2017

1/2017, 4/2017

3/2016

Erik Axell FOI – Swedish Defence Reasearch Agency

Andreas Westlund Volvo Car Corporation

Ingvar Karlsson Ericsson AB

Jan Carlsson Provinn AB

3/2014, 4/2014, 1/2015

Lennart Hasselgren EMC Services

Pär Weilow Swedavia

2/2015, 2/2018, 3/2018

1/2014

Marcus Eklund El/Tele Västfastigheter

Sara Linder FOI – Swedish Defence Reasearch Agency

3/2017

Carl Samuelsson Saab Aeronautics, Saab AB

4/2014, 1/2015, 2/2015, 3/2015, 4/2015, 1/2016, 2/2016, 3/2016, 4/2016, 1/2017, 2/2017, 3/2017, 4/2017, 1/2018, 2/2018, 3/2018

1/2015, 2/2015, 3/2015

Henrik Toss RISE Safety and Transport

Kristian Karlsson RISE Elektronik 1/2016

Lars Falk Stigab AB 2/2015

Lars-Erik Juhlin ABB Power Systems 1/2016 Leif Adelöw FOI – Swedish Defence Reasearch Agency 1/2015

2/2016

Mats Bäckström Saab Aeronautics, Saab AB 3/2016, 4/2017, 1/2018

Mats Lindgren RISE Elektronik 3/2014, 4/2014, 1/2015

Mattias Elfsberg FOI – Swedish Defence Reasearch Agency 1/2015

Michael Pattinson NSL 1/2018

Mikael Alexandersson FOI – Swedish Defence Reasearch Agency 1/2014, 1/2018

Mose Akyuz FOI – Swedish Defence Reasearch Agency 1/2015

Niklas Karpe Scania CV AB 3/2016

Patrik Eliardsson FOI – Swedish Defence Reasearch Agency 2/2016, 1/2018

Per Ängskog Högskolan Gävle/KTH 3/2016

Peter Ankarson RISE Elektronik 4/2014

Peter Larsson KTH

3/2015

Simon Loe Spirent Communications 2/2017

Sten E Nyholm FOI – Swedish Defence Reasearch Agency 1/2015, 2/2015, 3/2015

Susanne Otto Reliability DELTA Test & Consultancy 1/2015

Thomas Borglin SEK – Svensk Elstandard 1/2018

Tomas Bodeklint RISE Elektronik 2/2014

Tomas Hurtig FOI – Swedish Defence Reasearch Agency 1/2015, 2/2015, 3/2015

Torbjörn Persson Provinn AB 4/2016, 3/2017

Ulf Carlberg RISE Elektronik 4/2014

Ulf Nilsson Electronic Environment 2/2015 Åsa Larsbo Intertek Semko 1/2014

1/2016

Peter Stenumgaard FOI – Swedish Defence Reasearch Agency 3/2014, 4/2014, 3/2015, 4/2015, 1/2016, 4/2016, 1/2017, 3/2017

1/2014

www.electronic.nu – Electronic Environment online

35


Företagsregister Acal AB Solna Strandväg 21 171 54 Solna Tel: 08-546 565 00 Fax: 08-546 565 65 info@acal.se www.acal.se Adopticum Gymnasievägen 34 Leveransadress: Anbudsgatan 5 931 57 Skellefteå Tel: 0910-288 260 info@adopticum.se www.adopticum.se

Alpharay Teknik AB Runnabyvägen 11 705 92 Örebro Tel: 019-26 26 20 mail@alpharay.se www.alpharay.se Aleba AB Västberga allé 1 126 30 Hägersten Tel: 08-19 03 20 Fax: 08-19 35 42 www.aleba.se Alelion Batteries Flöjelbergsgatan 14c 431 37 Mölndal Tel: 031-86 62 00 info@alelion.com www.alelion.com/sv

AMB Industri AB 361 93 Broakulla Tel: 0471-485 18 Fax: 0471-485 99 Amska Amerikanska Teleprodukter AB Box 88 155 21 Nykvarn Tel: 08-554 909 50 Kontaktperson: Kees van Doorn www.amska.se Amtele AB Jägerhorns väg 10 141 75 Kungens Kurva Tel 08-556 466 04 Stora Åvägen 21 436 34 Askim Tel: 08-556 466 10 amtele@amtele.se www.amtele.se Anritsu AB Borgarfjordsgatan 13 A 164 26 Kista Tel: 08-534 707 00 Fax: 08-534 707 30 www.eu.anritsu.com ANSYS Sweden Färögatan 33 164 51 Kista Tel: 08-588 370 60 Vestagatan 2 B 416 64 Göteborg Tel: 031-771 87 80 info-se@ansys.com www.ansys.com Armeka AB Box 32053 126 11 Stockholm Tel: 08-645 10 75 Fax: 08-19 72 34 www.armeka.se Axiom EduTech Gjuterivägen 6 311 32 Falkenberg Tel: 0346-71 30 30 Fax: 0346-71 33 33 www.axiom-edutech.com

36

Electronic Environment #3.2018 Berako AB Regulatorv 21 14149 Huddinge Tel: 08-774 27 00 Fax: 08-779 85 00 www.berako.se

CE-BIT Elektronik AB Box 7055 187 11 Täby Tel: 08-735 75 50 Fax: 08-735 61 65 info@cebit.se www.cebit.se

BK Services Westmansgatan 47 A 582 16 Linköping Tel: 013–21 26 50 Fax: 013–99 13 025 johan@bk-services.se www.bk-services.se

CLC SYSTEMS AB Nygård Torstuna 740 83 Fjärdhundra Tel: 0171-41 10 30 Fax: 0171-41 10 90 info@clcsystems.se www.clcsystems.se

Kontaktperson: Johan Bergstrand

Bodycote Ytbehandling AB Box 58 334 21 Anderstorp Tel: 0371-161 50 Fax: 0371-151 30 www.bodycote.se Bofors Test Center AB Box 418 691 27 Karlskoga Tel: 0586-84000 www.testcenter.se Bomberg EMC Products Aps Gydevang 2 F DK 3450 Alleröd Danmark Tel: 0045-48 14 01 55 Bonab Elektronik AB Box 8727 402 75 Göteborg Tel: 031-724 24 24 Fax: 031-724 24 31 www.bonab.se BRADY AB Vallgatan 5 170 69 Solna Tel: 08-590 057 30 Fax: 08-590 818 68 cssweden@bradyeurope.com www.brady.se www.bradyeurope.com Bromanco Björkgren AB Rallarvägen 37 184 40 Åkersberga Tel: 08-540 853 00 Fax: 08-540 870 06 info@bromancob.se www.bromancob.se Båstad Industri AB Box 1094 269 21 Båstad Tel: 0431-732 00 Fax: 0431-730 95 www.bastadindustri.se CA Mätsystem Sjöflygsvägen 35 183 62 Täby Tel: 08-505 268 00 Fax: 08-505 268 10 www.camatsystem.se Cadputer AB Kanalvägen 12 194 61 Upplands Väsby Tel: 08-590 752 30 Fax: 08-590 752 40 www.cadputer.se

Combinova Marketing AB Box 200 50 161 02 Bromma Tel: 08-627 93 10 Fax: 08-29 59 85 sales@combinova.se www.combinova.se Combitech AB Gelbgjutaregatan 2 581 88 Linköping Tel: 013-18 00 00 Fax: 013-18 51 11 emc@combitech.se www.combitech.se Compomill AB Box 4 194 21 Upplands Väsby Tel: 08-594 111 50 Fax: 08-590 211 60 www.compomill.se DELTA Development Technology AB Finnslätten, Elektronikgatan 47 721 36 Västerås Tel: 021-31 44 80 Fax. 021-31 44 81 info@delta-dt.se www.delta-dt.se DeltaElectric AB Kraftvägen 32 Box 63 196 22 Kungsängen Tel: 08-581 610 10 www.deltanordicgroup.se/ deltaeltech

CCC Solutions AB/Carpatec Sågvägen 40 184 40 Åkersberga Tel: 08-540 888 45 hl@cccsolutions.eu http://www.cccsolutions.eu

ELKUL Kärrskiftesvägen 10 291 94 Kristianstad Tel: 044-22 70 38 Fax: 044-22 73 38 www.elkul.se

Elastocon AB Göteborgsvägen 99 504 60 Borås Tel: 033-22 56 30 Fax: 033-13 88 71 www.elastocon.se

Elrond Komponent AB Box 1220 141 25 Huddinge Tel: 08-449 80 80 Fax: 08-449 80 89 www.elrond.se

ELDON AB Transformatorgatan 1 721 37 Västerås Tel: 010-555 95 50 eldonindustrial.se@eldon.com www.eldon.com/sv-SE

EMC Väst AB Bror Nilssons Gata 4 417 55 Göteborg Tel: 031-51 58 50 Fax: 031-51 58 50 info@emcvaest.se www.emcväst.se

Electronix NG AB Enhagsvägen 7 187 40 Täby Tel: 010-205 16 50 Elis Elektro AS Jerikoveien 16 N-1067 Oslo Tel: +47 22 90 56 70 Fax: + 47 22 90 56 71 www.eliselektro.no

Emka Scandinavia Box 3095 550 03 Jönköping Tel: 036-18 65 70

EMC Services Box 30 431 21 Mölndal Besöksadress: Bergfotsgatan 4 Tel: 031-337 59 00 www.emcservices.se

ERDE-Elektronik AB Spikgatan 8 235 32 Vellinge Tel: 040-42 46 10 Fax: 040-42 62 18 info@erde.se web: www.erde.se

Kontaktperson: Tony Soukka tony@emcservices.se

Kontaktperson: Ralf Danielsson

Emicon AB Head office: Briggatan 21 234 42 Lomma Branch office: Luntmakargatan 95 113 51 Stockholm Tel: 040-41 02 25 or 073-530 71 02 sven@emicon.se www.emicon.se

Produkter och Tjänster: Skandinavisk representant för schweiziska EMC-Partner AG. Vi har provutrustning för IEC, EN, ISO, MIL mfl standarder samt för harmonics, flicker, emission och immunitet. Transientgeneratorer för bla immunitets- och komponentprovning samt blixtprovning av flygplans-, telekom- och militärutrustning.

Contact: Sven Garmland

ESD-Center AB Ringugnsgatan 8 216 16 Malmö Tel: 040-36 32 40 Fax: 040-15 16 83 www.esd-center.se

Detectus AB Hantverkargatan 38 B 782 34 Malung Tel: 0280-411 22 Fax: 0280-411 69 jan.eriksson@detectus.se www.detectus.se

EMP-Tronic AB Box 130 60 250 13 Helsingborg Tel: 042-23 50 60 Fax: 042-23 51 82 www.emp-tronic.se

Kontaktperson: Jan Eriksson

Kontakt person: Lars Günther

Produkter och Tjänster: Instrument, provning. Detectus AB utvecklar, producerar och säljer EMC-testsystem på världsmarknaden. Företaget erbjuder också hyra och leasing av mätsystemet. Detectus har möjlighet att utföra konsultmätningar (emission) på konsultbasis i egna lokaler.

Caltech AB Fågelviksvägen 7 145 53 Norsborg Tel: 08-534 703 40 Fax: 08-531 721 00 www.caltech.se

EG Electronics AB Grimstagatan 160 162 58 Vällingby Tel: 08-759 35 70 Fax: 08-739 35 90 www.egelectronics.com

DeltaEltech AB Box 4024 891 04 Örnsköldsvik Tel: 0660-29 98 50 www.deltanordicgroup.se/ deltaeltech/

Emp-tronic AB är specialiserat på Elmiljö- och EMCteknik.

Produkter och Tjänster: Vi har levererat skärmade anläggningar i över 25 år till bl.a. försvaret och myndigheter som skydd för EMP, RÖS, HPM med kontorsmiljö. Vi levererar även utrustning och skärmrum för EMC-mätning, elektronikkalibrering eller antennmätning, även med modväxelteknik. I vårt fullutrustade EMC-lab kan vi erbjuda verifierad provning för CE-märkning.

www.electronic.nu – Electronic Environment online

Eurodis Electronics 194 93 Stockholm Tel: 08-505 549 00 Exapoint Svenska AB Box 195 24 104 32 Stockholm Tel: 08-501 64 680 www.exapoint.se ExCal AB Bröksmyravägen 43 826 40 Söderhamn Tel: 0270-28 87 60 Fax: 0270-28 87 70 info@excal.se www.excal.se Farnell Skeppsgatan 19 211 19 Malmö Tel: 08-730 50 00 www.farnell.se Ferner Elektronik AB Box 600 175 26 Järfälla Tel: 08-760 83 60 www.ferner.se


Företagsregister

Electronic Environment #3.2018

Flexitron AB Veddestavägen 17 175 62 Järfälla Tel: 08-732 85 60 sales@flexitron.se www.flexitron.se Produkter och Tjänster: Vi erbjuder ett brett och djupt sortiment av produkter för EMC samt termiska material från tillverkare som är marknadsledande inom sina respektive områden. Exempel på produkter är skärmningslister, skärmburkar, ledande plast, färg, fett och lim, skärmburkar, genomföringsfilter, mikrovågsabsorbenter, etc. Vi har stor möjlighet att kundanpassa produkterna, aningen direkt från tillverkaren eller i vår egen verkstad.

FMV 115 88 Stockholm Tel: 08-782 40 00 Fax: 08-667 57 99 www.fmv.se Frendus AB Strandgatan 2 582 26 Linköping Tel: 013-12 50 20 info@frendus.com www.frendus.com Kontaktperson: Stefan Stenmark

Industrikomponenter AB Gårdsvägen 4 169 70 Solna Tel: 08-514 844 00 Fax: 08-514 844 01 www.inkom.se Infineon Technologies Sweden AB Isafjordsgatan 16 164 81 Kista Tel: 08-757 50 00 www.infineon.com Ing. Firman Göran Gustafsson Asphagsvägen 9 732 48 Arboga Tel: 0589-141 15 Fax: 0589-141 85 www.igg.se Ingenjörsfirman Gunnar Petterson AB Ekebyborna 254 591 95 Motala Tel: 08-93 02 80 Fax: 0141-711 51 hans.petterson@igpab.se www.igpab.se Instrumentcenter Folkkungavägen 4 Box 233 611 25 Nyköping Tel: 0155-26 70 31 Fax: 0155-26 78 30 info@instrumentcenter.se www.instrumentcenter.se

Intertechna AB Kvarnvägen 15 663 40 Hammarö Tel: 054-52 10 00 Fax: 054-52 22 97 www.intertechna.se

Garam Elektronik AB Box 5093 141 05 Huddinge Tel: 08-710 03 40 Fax: 08-710 42 27

Intertek Torshamnsgatan 43 Box 1103 164 22 Kista Tel: 08-750 00 00 Fax: 08-750 60 30 Info-sweden@intertek.com www.intertek.se

Glenair Nordic AB Box 726 169 27 Solna Tel: 08-505 500 00 Fax: 08- 505 500 00 www.glenair.com

INNVENTIA AB Torshamnsgatan 24 B 164 40 Kista Tel: 08-67 67 000 Fax: 08-751 38 89 www.innventia.com

Gore & Associates Scand AB Box 268 431 23 Mölndal Tel: 031-706 78 00 www.gore.com Helukabel AB Spjutvägen 1 175 61 Järfälla Tel: 08-557 742 80 Fax: 08-621 00 59 www.helukabel.se High Voltage AB Änggärdsgatan 12 721 30 Västerås Tel: 021-12 04 05 Fax: 021-12 04 09 www.highvoltage.se HP Etch AB 175 26 Järfälla Tel: 08-588 823 00 www.hpetch.se

Jan Linders EMC-provning Bror Nilssons gata 4 417 55 Göteborg Tel: 031-744 38 80 Fax: 031-744 38 81 info@janlinders.com www.janlinders.com Kontaktperson: Jan Linders Produkter och tjänster: EMC-provning, elektronik och EMC, utbildning, EMIanalys, allmän behörighet. Jan Linders Ingenjörsfirma har mångårig erfarenhet inom EMC-området och har allmän behörighet upp till 1 000 V. Bland vårt utbud märks ce-märkning, prototypprovning samt mätning och provning hos kund. Vi utför EMC-styling dvs förbättrar produkters EMC-egenskaper, ger råd och hjälp om standarder m m. Med vår nya EMC-tjänst tar vi totalansvar för er EMC-certifiering.

Jolex AB Västerviksvägen 4 139 36 Värmdö Tel: 08-570 229 85 Fax: 08 570 229 81 mail@jolex.se www.jolex.se Kontaktperson: Mikael Klasson Produkter och Tjänster: EMC, termiska material och kylare Jolex AB har mångårig erfarenhet inom EMC och termiskt. Skärmningslister/kåpor, mikrovågsabsorbenter, icke ledande packningar, skärmande fönster/glas/rum/ dörrar, genomföringskondensatorer, kraftfilter, data-, telekom-, utrustnings- och luftfilter, ferriter, jordflätor, termiska material och kylare etc. Vi kundanpassar produkter och volymer. Jontronic AB Centralgatan 44 795 30 Rättvik Tel: 0248-133 34 info@jontronic.se www.jontronic.se

KAMIC Components Körkarlsvägen 4 653 46 Karlstad Tel: 054-57 01 20 info@kamic.se www.kamicemc.se Produkter och Tjänster: Med närmare 30 års erfarenhet och ett brett program av elmiljöprodukter erbjuder KAMIC Components allt från komponenter till färdiga system. Lösningarna för skalskydd omfattar lådor, skåp och rum för EMI-, EMP- och RÖS-skydd. Systemlösningar som uppfyller MIL-STD 285 och är godkända enligt skalskyddsklasserna SS1 och SS2. Komponenter, ledande packningar och lister. KAMIC Components är en del av KAMIC Installation AB. Kontaktperson: Jörgen Persson. KEMET Electronics AB Thörnbladsväg 6, 386 90 Färjestaden Tel: 0485-56 39 00 TobiasHarlen@kemet.com www.kemet.com/dectron

Kvalitest Sweden AB Flottiljgatan 61 721 31 Västerås Tel:076-525 50 00 sales@kvalitetstest.com www.kvalitetstest.com

LaboTest AB Datavägen 57 B 436 32 Askim Tel: 031-748 33 20 Fax: 031-748 33 21 info@labotest.se www.labotest.se Produkter och Tjänster: LaboTest AB marknadsför och underhåller utrustningar i Sverige till lab och produktionsavdelningar inom miljötålighet och test. Vårt huvudkontor finns i Askim och vårt filialkontor i Sollentuna. Våra huvudleverantörer är Vötsch och Heraeus. Båda har en världsomspännande organisation och är marknadsledande inom sina respektive produktområde. Vår verksamhet fokuseras främst kring följande produktområden: Värmeskåp, Torkugnar, Vakuumtorkskåp, Temperatur-, Klimattestkammare, Chocktest- kammare, Sol/Vädertestkammare, Vibrationstestkammare, Klimatiserade rum, Saltspraytestkammare, HALT/ HASS-kammare.

LAI Sense Electronics Rördromsvägen 12 590 31 Borensberg Tel: 0703-45 55 89 Fax: 0141-406 42 www.laisense.com LeanNova Engineering AB Flygfältsvägen 7 461 38 Trollhättan Tel: 072-370 07 58 info@leannova.se www.leannova.se

LINDH Teknik Granhammar 144 744 97 Järlåsa Tel: 018-444 33 41 Mobil: 070-664 99 93 kenneth@lindhteknik.se www.lindhteknik.se Lintron AB Box 1255 581 12 Linköping Tel: 013-24 29 90 Fax: 013-10 32 20 www.lintron.se

Keysight Technologies Sweden AB Färögatan 33 164 51 Kista Tel: 0200-88 22 55 kundcenter@keysight.com www.keysight.com

LTG Keifor AB (KAMIC) Box 8064 163 08 Spånga Tel: 08-564 708 60 Fax: 08-760 60 01 kamic.karlstad@kamic.se www.kamic.se Lundinova AB Dalbyvägen 1 224 60 Lund Tel: 046-37 97 40 Fax: 046-15 14 40 www.lundinova.se

Kitron AB 691 80 Karlskoga Tel: 0586-75 04 00 Fax: 0586-75 05 90 www.kitron.com

Magnab Eurostat AB Pontongatan 11 611 62 Nyköping Tel: 0155-20 26 80 www.magnab.se

www.electronic.nu – Electronic Environment online

Megacon AB Box 63 196 22 Kungsängen Tel: 08-581 610 10 Fax: 08-581 653 00 www.megacon.se MTT Design and Verification Propellervägen 6 B 183 62 Täby Tel: 08-446 77 30 sales@mttab.se www.mttab.se

Mentor Graphics Färögatan 33 164 51 Kista Tel: 08-632 95 00 www.mentor.com Metric Teknik Box 1494 171 29 Solna Tel: 08-629 03 00 Fax: 08-594 772 01 Mikroponent AB Postgatan 5 331 30 Värnamo Tel: 0370-69 39 70 Fax: 0370-69 39 80 www.mikroponent.se Miltronic AB Box 1022 611 29 Nyköping Tel: 0155-777 00 MJS Electronics AB Box 11008 800 11 Gävle Tel: 026-18 12 00 Fax: 026-18 06 04 www.mjs-electronics.se MPI Teknik AB Box 96 360 50 Lessebo Tel: 0478-481 00 Fax: 0478-481 10 www.mpi.se NanoCal AB Lundbygatan 3 621 41 Visby Tel: 0498-21 20 05 www.nanocal.se Nefab Packaging AB 822 81 Alfta Tel: 0771-59 00 00 Fax: 0271-590 10 www.nefab.se Nelco Contact AB Box 7104 192 07 Sollentuna Tel: 08-754 70 40 Nemko Sweden Enhagsslingan 23 187 40 Täby Tel: 08-47 300 30 www.nemko.no Nohau Solutions AB Derbyvägen 4 212 35 Malmö Tel: 040-59 22 00 Fax: 040-59 22 29 www.nohau.se Nolato Silikonteknik AB Bergmansvägen 4 694 91 Hallsberg Tel: 0582-889 00 Nortelco AS Ryensvingen 3 N-0680 Oslo Tel: +47 22576100 Fax: +47 22576130 elektronikk@nortelco.no www.nortelco.no

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Företagsregister Nortronicom AS Ryensvingen 5 Postboks 33 Manglerud N-0612 Oslo Tel: +47 23 24 29 70 Fax: +47 23 24 29 79 www.nortronicom.no Nässjö Plåtprodukter AB Box 395 571 24 Nässjö Tel: 031-380 740 60 www.npp.se OBO Bettermann AB Florettgatan 20 254 67 Helsingborg Tel: 042-38 82 00 Fax: 042-38 82 01 www.obobettermann.se

OEM Electronics AB Box 1025 573 29 Tranås Tel: 075-242 45 00 www.oemelectronics.se ONE Nordic AB Box 50529 202 50 Malmö Besöksadress: Arenagatan 35 215 32 Malmö Tel: 0771-33 00 33 Fax: 0771-33 00 34 info@one-nordic.se

Prevas AB Hammarby Kaj 18 120 30 Stockholm Tel: 08-644 14 00 maria.mansson@prevas.se www.prevas.se Kontaktperson: Maria Månsson Produkter: Utveckling

PROXITRON AB Box 324 591 24 Motala Tel: 0141-580 00 Fax: 0141-584 95 info@proxitron.se www.proxitron.se Kontaktperson: Rickard Elf Produkter och Tjänster: INSTRUMENT. Proxitron AB arbetar med försäljning och service inom elektronikbranschen. Vi samarbetar med en rad ledande internationella tillverkare inom områdena; Klimat/Vibration, EMC, Givare, Komponenter, Högspänning och Elsäkerhet. Våra kunder finns över hela Skandinavien och representerar forskning/utveckling, produktion, universitet och högskolor.

Electronic Environment #3.2018 RF Partner AB Flöjelbergsgatan 1 C 431 35 Mölndal Tel: 031-47 51 00 Fax: 031-47 51 21 info@rfpartner.se www.rfpartner.se-

Provinn AB Kvarnbergsgatan 2 411 05 Göteborg Tel: 031 – 10 89 00 info@provinn.se www.provinn.se Products and Services: Provinn offer EMC expertise covering all aspects from specification through consultant services, education, numerical analyses all the way to final verification. We are several dedicated EMC experts with documented expertise and experience. Provinn is proud representative for Oxford Technical Solutions (OxTS) navigational equipment, Moshon Data ADAS test equipment and Spirent GPS/GNSS instruments for the Scandinavian market.

Ornatus AB Stockholmsvägen 26 194 54 Upplands Väsby Tel: 08-444 39 70 Fax: 08-444 39 79 www.ornatus.se Para Tech Coating Scandinavia AB Box 567 175 26 Järfälla Besök: Elektronikhöjden 6 Tel: 08-588 823 50 info@paratech.nu www.paratech.nu Phoenix Contact AB Linvägen 2 141 44 Huddinge Tel: 08-608 64 00 order@phoenixcontact.se www.phoenixcontact.se Polystar Testsystems AB Mårbackagatan 19 123 43 Farsta Tel: 08-506 006 00 Fax: 08-506 006 01 www.polystartest.com Processbefuktning AB Örkroken 11 138 40 Älta Tel: 08-659 01 55 Fax: 08-659 01 58 www.processbefuktning.se Procurator AB Box 9504 200 39 Malmö Tel: 040-690 30 00 Fax: 040-21 12 09 www.procurator.se Profcon Electronics AB Hjärpholn 18 780 53 Nås Tel: 0281-306 00 Fax: 0281-306 66 www.profcon.se

RISE Elektronik Box 857 501 15 Borås Tel: 010-516 50 00 info@ri.se www.ri.se Kontaktperson: Christer Karlsson Produkter och tjänster: RISE Elektronik (fd SP Sveriges Tekniska Forskningsinstitut) hjälper dig med oberoende kunskap och provning inom elsäkerhet, EMC, radioutrustning, maskinsäkerhet, IP-klassning, funktionssäkerhet samt mekanisk och klimatisk miljötålighet. I laboratorierna sker allt från utvecklingsprovning till ackrediterade prov. Vi ger både öppna och kundspecifika kurser inom flera områden. En omfattande forskning bedrivs för att säkra spetskompetensen i samverkan med industri, akademi och andra forskningsinstitut. Kontaktperson: Christer Karlsson

Rittal Scandinavian AB Månskärsgatan 7 141 71 Huddinge Tel: 08-680 74 08 Fax: 08-680 74 06 www.rittal.se Rohde & Schwarz Sverige AB Flygfältsgatan 15 128 30 Skarpnäck Tel: 08-605 19 00 Fax: 08-605 19 80 info.sweden@rohdeschwarz. com www.rohde-schwarz.se

Ronshield AB Kallforsvägen 27 124 32 Bandhagen Tel: 08-722 71 20 Fax: 08 556 720 56 info@ronshield.se www.ronshield.se Kontaktpersoner: Ronald Brander Produkter och Tjänster: Produkter: Kompletta EMC-mätplatser/hallar, absorbenter, ferriter, vridbord, antenner, antennmaster, TEM-Cell, Strip­lines, EMC-Mätinstrument och system, Audio-video system, fiberoptiska styrningar, EMC-­ Filter, RÖS-Rum, EMP-Skydd/ Filter, Utbildning.

Roxtec International AB Box 540 371 23 Karlskrona Tel: 0455-36 67 23 www.roxtec.se RS Components AB Box 21058 200 21 Malmö Tel: 08-445 89 00 Fax:08-687 11 52 www.rsonline.se RTK AB Box 7391 187 15 Täby Tel: 08-510 255 10 Fax: 08-510 255 11 info@rtk.se www.rtk.se RUTRONIK Nordic AB Kista Science Tower Färögatan 33 164 51 Kista Tel: 08-505 549 00 Fax: 08-505 549 50 www.rutronik.se Saab AB, Aeronautics, EMC-labbet Gelbgjutaregatan 2 581 88 Linköping Tel: 013-18 00 00 andreas.naslund@saabgroup.com Saab AB, Surveillance A15 – Compact Antenna Test Range Bergfotsgatan 4 431 35 Mölndal Tel: 031-794 81 78 christian.augustsson@saabgroup.com www.saabgroup.com

Proxy Electronics AB Box 855 391 28 Kalmar Tel: 0480-49 80 00 Fax: 0480 49 80 10 www.proxyelectronics.com

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www.electronic.nu – Electronic Environment online

Saab AB, Support and Services, EMC-laboratory P.O Box 360 S-831 25 Östersund Tel: +46 63 1 560 00 Fax: 063-15 61 99 www.emcinfo.se www.saabgroup.com Contact: Örjan Festin Products & Services: We offer accredited EMC testing in accordance with most commercial and military standards and methods, including airborne equipment. We can also provide pre-compliance testing and qualified reviews and guidance regarding EMC during product design.

Saab EDS Nettovägen 6 175 88 Järfälla Tel: 08-580 850 00 www.saabgroup.com Scanditest Sverige AB Box 182 184 22 Åkersberga Tel: 08-544 019 56 Fax: 08-540 212 65 www.scanditest.se info@scanditest.se Scandos AB Varlabergsvägen 24 B 434 91 Kungsbacka Tel: 0300-56 45 30 Fax: 0300-56 45 31 www.scandos.se Schaffner EMC AB Turebergstorg 1 191 86 Sollentuna Tel: 08-579 211 22 Fax: 08-92 96 90 Schroff Skandinavia AB Box 2003 128 21 Skarpnäck Tel: 08-683 61 00 Schurter Nordic AB Sandborgsvägen 50 122 33 Enskede Tel: 08-447 35 60 Fax: 08-605 47 17 www.schurter.se SEBAB AB Sporregatan 12 213 77 Malmö Tel: 040-601 05 00 Fax: 040-601 05 10 www.sebab.se


Företagsregister

Electronic Environment #3.2018

SEK Svensk Elstandard Box 1284 164 29 KISTA Tel: 08-444 14 00 sek@elstandard.se www.elstandard.se Shop.elstandard.se Produkter och Tjänster: Du kan genom deltagande i SEK Svensk Elstandard och den nationella och internationella standardiseringen vara med och påverka framtidens standarder samtidigt som ditt företag får en ökad affärsnytta och ökad konkurrenskraft. På SEK Shop, www.elstandard.se/shop, hittar du förutom svensk standard även europeisk och internationell standard inom elområdet. SEK ger även ut SEK Handböcker som förklarar och fördjupar, vägleder och underlättar ditt användande av standarder. Läs mer på www.elstandard.se. SGS Fimko AB Mörtnäsvägen 3 (PB 30) 00210 Helsingfors Finland www.sgs.fi

Shortlink AB Stortorget 2 661 42 Säffle Tel: 0533-468 30 Fax: 0533-468 49 info@shortlink.se www.shortlink.se

Swerea KIMAB AB Box 7047 Isafjordsgatan 28 164 40 Kista Tel: 08-440 48 00 elektronik@swerea.se www.swereakimab.se

Sims Recycling Solutions AB Karosserigatan 6 641 51 Katrineholm Tel: 0150-36 80 30 www.simsrecycling.se

TEBAB, Teknikföretagens Branschgrupper AB Storgatan 5, Box 5510, 114 85 Stockholm Tel +46 8 782 08 08 Tel vx +46 8 782 08 50 www.sees.se

Skandinavia AB Box 2003 128 21 Skarpnäck Tel: 08-683 61 00 Turebergstorg 1 191 86 Sollentuna Tel: 08-579 211 22 Fax: 08-92 96 90 STF Ingenjörsutbildning AB Malmskillnadsgatan 48 Box 1419 111 84 Stockholm Tel: 08-613 82 00 Fax: 08-21 49 60 www.stf.se

Stigab Fågelviksvägen 18 145 53 Norsborg Tel: 08-97 09 90 info@stigab.se www.stigab.se Swentech Utbildning AB Box 180 161 26 Bromma Tel: 08-704 99 88 www.swentech.se

Technology Marketing Möllersvärdsgatan 5 754 50 Uppsala Tel: 018-18 28 90 Fax: 018-10 70 55 www.technologymarketing.se Tesch System AB Märstavägen 20 193 40 Sigtuna Tel: 08-594 80 900 order@tufvassons.se www.tesch.se Testhouse Nordic AB Österögatan 1 164 40 Kista Landskronavägen 25 A 252 32 Helsingborg Tel: 08-501 260 50 Fax: 08-501 260 54 info@testhouse.se www.testhouse.se Tormatic AS Skreppestad Naringspark N-3261 Larvik Tel: +47 33 16 50 20 Fax: +47 33 16 50 45 www.tormatic.no

Trafomo AB Box 412 561 25 Huskvarna Tel: 036-38 95 70 Fax: 036-38 95 79 www.trafomo.se

Weidmüller AB Box 31025 200 49 Malmö Tel: 0771-43 00 44 Fax: 040-37 48 60 www.weidmuller.se

Treotham AB Box 11024 100 61 Stockholm Tel: 08-555 960 00 Fax: 08- 644 22 65 www.treotham.se

Wretom Consilium AB Olof Dalins Väg 16 112 52 Stockholm Tel: 08-559 265 34 info@wretom.se www.wretom.se

TRESTON GROUP AB Tumstocksvägen 9 A 187 66 Täby Tel: 08-511 791 60 Fax: 08-511 797 60 Bultgatan 40 B 442 40 Kungälv Tel: 031-23 33 05 Fax: 031-23 33 65 info.se@trestoncom www.treston.com

Würth Elektronik Sweden AB Annelundsgatan 17 C 749 40 Enköping Tel: 0171-41 00 81 eiSos-sweden@we-online.com www.we-online.se Kontaktperson: Martin Danielsson

Trinergi AB Halltorpsvägen 1 702 29 Örebro Tel: 019-18 86 60 Fax: 019-24 00 60 UL International (Sweden) AB An affiliate of Underwriters Laboratories Inc. Stormbyvägen 2-4 163 29 Spånga Tel: 08-795 43 70 Fax: 08-760 03 17 www.ul-europe.com

Yokogawa Measurement Technologies AB Finlandsgatan 52 164 74 Kista Tel: 08-477 19 00 Fax: 08-477 19 99 www.yokogawa.se Österlinds El-Agentur AB Box 96 183 21 Täby Tel: 08-587 088 00 Fax: 08-587 088 02 www.osterlinds.se

Vanpee AB Karlsbodavägen 39 168 67 Bromma Telefon: 08-445 28 00 www.vanpee.se order@vanpee.se

WE’LL BE BACK Gothenburg 2022

www.electronic.nu – Electronic Environment online

39


POSTTIDNING B  Returer till: Break a Story Mässans gata 14 412 51 Göteborg

v

EMC-TESTUTRUSTNING

EMF-mätare (EMF=ElektroMagnetiskaFält) från Microrad, NHT 3D och NHT 310 Microrads EMF-mätare finns i två utföranden. Modell NHT 3D för analys av komplexa signaler i tid-och frekvensdomän samt mätningar enligt standard/direktiv, Modell NHT 310 för mätning enligt standard/direktiv. Båda modellerna är batteridrivna (laddningsbara), har inbyggd temperatursensor och GPS mottagare samt interface för fiberkommunikation. Tillämpliga direktiv och standarder är 2013/35EU, CEI EN 50500, CEI EN 62233 och CEI EN 62311. Displayen visar gränsen för tillåtna värden enligt nämnda standard och direktiv. Frekvensområdet för båda modellerna är 0-40GHz med probar inom området. Dessutom finns kombinationsprober för E-, H- och B-fält

Modell NHT 3D

Modell NHT 310

Fr.omr. bredband: 100k-40GHz smalband: DC-400kHz Sampling: max 2Msps Mätenheter: V/m, A/m, W/m2 mW/cm2, µT, mT Display omr. 0,00001-999,999. Tid-domän analys oscilloskopfunktion med manuell eller automatisk trigger. Frekvens-domän och FFT spektrumanalys i realtid med 65 536 samples. Programvaran Waves medföljer.

Probar Programmet omfattar probar för E-fält från 1Hz till 40GHz samt H-fält och B-fält från 0 -400kHz. Här följer specifikationer på 2 av de vanligast förekommande probarna.

Fr.omr. DC-40GHz Mätenheter: V/m, A/m, W/m2, mW/cm2, uT, mT. Display omr. 0,00001-999,999. Batteridrift: >72 timmar. Inspelningstid: > 24 timmar i steg om 5s. Programvaran MicroLink medföljer. Instrumenten levereras i transportväska med tillbehör och plats för 2 st probar samt kalibreringscertifikat och programvara.

Modell 33P

Elektrisk fältstyrka, E-fält : 1Hz-400kHz Dynamiskt område : >60dB Mätområde: 20V/m-20kV/m Magnetisk fältstyrka, H-fält: DC Dynamiskt område: >60dB Mätområde: 5µT-5mT Magnetisk flödestäthet, B: 1Hz-400kHz Dynamiskt område: >94dB Mätområde: 300nT-16mT

Modell 01E

Elektrisk fältstyrka, E-fält: 100kHz6,5GHz Dynamiskt område: 65dB Mätområde: 0,2V/m- 360V/m

Mättjänster Vi utför mätningar av EMF-fält och kommer till Er med utrustning. Efter utförda analyser och mätningar levereras protokoll och i förekommande fall förslag till åtgärder. Skicka ett e-mail till info@cebit.se och vi kontaktar Er.

Programvara för EMC-provning

Ferriter för störundertryckning

Med RadiMation® från DARE Instruments kan Du automatisera dina EMCtester, både när det gäller immunitet och emission, ledningsbundet och med antenn. Drivrutiner för över 3000 på marknaden förekommande instrument. Kontakta oss för mer information.

Fair-Rite material 75 är speciellt framtaget för att dämpa i det lägre frekvensområdet mellan 200kHz till 5MHz. Beställ en provtavla – du betalar bara för frakten.

CE-BIT – Box 7055, 187 11 Täby, Sweden – Tel: +46 8-735 75 50 - Fax. +46 8-735 61 65 – E-Mail: info@cebit.se – www.cebit.se


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