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t 0 es 1 W 20 B er PC mb e pt Se

A Wiki-based Parts Library, pg. 8

What Lies Beneath

Characterizing the Cleanability of OA Solder

Materials Management Tools Capacitor Testing 10 Electrical Design Lessons

5 Competitive Advantages Offshore Manufacturing Imagineering, Inc. enjoys the reputation of being one of the most experienced & successful offshore PCB suppliers.


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CAM USA Our Illinois based DFM office has eight fully staffed CAD / CAM stations. Within hours of receipt of new Gerber files, our highly experienced DFM engineers conduct thorough and precise analyses.

Quick-Turn Production Imagineering offers small volume production in 5-6 days and medium to large volume production in 2-3 weeks.

Overseas Manufacturing

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Capabilities: Up to 30 Layers Blind Buried Vias Di-Electric Thickness Impedance Control (TDR Tested) Plated Edge Holes Up to 6oz Copper 6 mil Laser Drill 3 mil line width/spacing Conductive Filled Vias Aluminum Metal Core Boards ...and many others

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AUGUST 2010 • VOL. 29 • NO. 8


Caveat Lector Use proper protection.

Mike Buetow 20



Talking Heads In a Flash. AsteelFlash’s Georges Garic.



Not a standard opinion.

Pete Waddell

Global Sourcing Can high-mix, low-volume production succeed in China?

Carl Hung 17

Material Management

Benefits of Factory Software Interoperability Manufacturers deploy various manufacturing systems that provide necessary controls, enable data collection, support cost-saving initiatives, provide a means for compliance, and help decrease time to market. Yet most remain as islands of information, and provide the value intrinsic within their own confined systems. Can overall equipment effectiveness be optimized by enhancing links between material flow, quality and surface mount technology programming, and monitoring data? by Jay Gorajia

money matters 16

A Wiki-based Parts Library, pg. 8

ROI Certifiable.

Peter Bigelow 18


Susan Mucha

tech talk Signal Doctor Ten electrical design lessons.


Dr. Eric Bogatin 24

Characterizing the Cleanability of OA Solder

Materials Management Tools Capacitor Testing 10 Electrical Design Lessons

ON THE COVER: Why visual indicators as a cleanliness gauge may be dangerous practice.

Electrical Test

Capacitor Testing Challenges and Solutions

Cover Story

Under-Component Cleaning: How Low Can You Go? Preventing field failures due to electrochemical migration used to be relatively easy: Use a water-soluble flux and clean the board after soldering. This solution no longer holds true, and sometimes causes more problems than it prevents. by Harald Wack, Ph.D., Umut Tosun, Joachim Becht, Ph.D., Helmut Schweigart, Ph.D., and Chrys Shea

designer’s notebook DfM, properly applied.

Max Clark 36

What Lies Beneath

Capacitors are widely used for bypassing, coupling, filtering and tunneling electronic circuits. However, to be useful, their capacitance value, voltage rating, temperature coefficient and leakage resistance must be characterized. Although capacitor manufacturers perform these tests, many electronics assemblers also perform some of these tests as quality checks. A look at the challenges associated with capacitor testing, and some of the test techniques used. by Dale Cigoy

Focus on Business Why one size doesn’t fit all.




0 t es 01 W 2 B er, PC mb e pt




Mike Buetow

Screen Printing Climate check.

Clive Ashmore 37

Defects Database Excess flux and PoP.

Dr. Davide Di Maio 38

Getting Lean When metrics fail.

Tony Bellito 39

SMT Troubleshooting A bridge from the printer.

Paul Lotosky 40

Tech Tips Show me your papers.



around the world



41 45

OFF THE SHELF marketplace


assembly insider


ad index

ACI Technologies Inc. 48

Technical Abstracts

POSTMASTER: Send address changes to PRINTED CIRCUIT DESIGN & FAB / CIRCUITS ASSEMBLY, P.O. Box 35621, Tulsa, OK 74153-0621

Learn About CAM350 XL™– The Next Generation PCB Post-Processing and Management Solution

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Editorial Editor in chief: Mike Buetow, 617-327-4702, SENIOR Editor: Chelsey Drysdale, 678-993-4806, fabrication technical Editor: Kathy Nargi-Toth design technical Editor: Pete Waddell editorial office: P.O. Box 470, Canton, GA 30169, 678-589-8800; fax 678-589-8850

PCD&F Editorial advisory Board: Dr. Eric Bogatin, George Dudnikov, Jack Fisher, Happy Holden, Istvan Novak

Circuits Assembly Editorial advisory Board: John D. Borneman, Heather McCormick, Chrys Shea, Curt Williams

Production Art Director: Rebekah Just,

Sales Printed Circuit Design & Fab Sales Manager: Frances Stewart, 678-817-1286,

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print Reprints: Edward Kane, Foster Printing, 866-879-9144 ext. 131, fax 219-561-2009, electronic Reprints:;

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List Rental: Jennifer Schuler, 918-496-1476, fax 918-496-9465 WEBINARS: Frances Stewart, 678-817-1286,,

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Circulation and Subscription Inquiries/address changes: fax 918-496-9465,

Complete Prototype Design with NI Ultiboard Layout

UP Media Group, Inc. president: Pete Waddell vice president, sales and marketing: Frances Stewart,

vice president, editorial and production: >>

Evaluate Multisim 11.0 at 800 263 5552

Mike Buetow, Printed Circuit Design & Fab/Circuits Assembly is distributed without charge to qualified subscribers. For others, annual Subscription Rates in U.S. funds are: $80 (U.S. and Canada), $145 (all other countries). Single copy price is $8.50. All subscription and single copy orders or inquiries should be directed to Printed Circuit Design & Fab/Circuits Assembly, P.O. Box 35621, Tulsa, OK 74153-0621,, fax 918-4969465. Photocopies and issues on Microfilm/Microfiche (16mm, 33mm or 105mm) are available from University Microfilms International, 300 N. Zeeb Rd., Ann Arbor, MI 48106, Telephone 313-761-4600. Printed Circuit Design & Fab/Circuits Assembly is published monthly by UP Media Group Inc., P.O. Box 470, Canton, GA 30169. ISSN 1543-6527. GST 124513185/ Agreement #1419617. Periodicals postage paid at Smyrna, GA, and additional mailing offices. Š 2010, UP Media Group, Inc. All rights reserved. Reproduction of material appearing in Printed Circuit Design & Fab/Circuits Assembly is forbidden without written permission.

Š2009 National Instruments. All rights reserved. National Instruments, NI, and are trademarks of National Instruments. Other product and company names listed are trademarks or trade names of their respective companies. 1Prices subject to change. 0691



2009-0895.indd 1

1/11/10 9:00:01 AM


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Edited by mike buetow


PCD&F Briefs Altium ( named Hansa PLMSolutions ( as a value-added reseller in Austria. Pegatron-Unihan ( cited Dow Electronic Materials with its 2009 Best Partner Award for performance in technology, support, quality, and logistics. Ontario will provide PWB fabricator FTG Circuits ( with more than $5 million in financial support for investments in advanced technology products and processes. Celestica ( recognized Viasystems Group ( as an honoree of its 2009 Total Cost of Ownership Supplier Award. European Circuits Ltd. (european-circuits. has opened a bare board manufacturing plant in Clydebank, Scotland, tripling the floor capacity of its previous plant, and has doubled its workforce to 33. Mentor Graphics’ ( board has adopted a Shareholder Rights Plan, granting each shareholder the opportunity to purchase one discounted share for each share of common stock held. The move came as corporate raider Carl Icahn amassed 11% of the company’s stock. Adeon Software House ( appointed Router Solutions ( as its exclusive distributor in Germany, Austria and Switzerland.

PCD&F People Endicott Interconnect Technologies named Joe Zachman chief operating officer. P. D. Circuits appointed Bill Hackett Eastern regional sales manager. He has 13 years’ experience as a sales manager with Epec Engineered Technologies and LogiCom. Dow Electronic Materials promoted Dr. Dominic Yang to business group vice president, superseding Dr. Yi Hyon Paik, who retired. A general manager with Rohm and Haas (now Dow) since 1997, Yang previously worked at IBM and Motorola, and holds a Ph.D. in organic chemistry from the University of Chicago. Multilayer Technology named Roy Alcus production/process engineer. He previously worked for DDI, Multek and Sierra Proto Express. Zuken named Steve Chidester head of product marketing for Europe and America.



Registration Open for PCB West 2010 SMYRNA, GA – Registration is now open for PCB West, the premier conference and

exhibition for PCB assembly engineers, designers, fabricators and managers. PCB West 2010 will be held Sept. 28 – 30 at the Santa Clara (CA) Convention Center and is sponsored by PCD&F and CIRCUITS ASSEMBLY. Now in its 19th year, PCB West provides show attendees – printed circuit board (PCB) engineers, designers, fabricators, assemblers and managers – with the most targeted conference in the PCB design industry. It is the only significant electronics manufacturing trade show in the Silicon Valley. Highlights include: ■■ A three-day technical conference consisting of more than 30 presentations, including 10 workshops, panel sessions and half-day seminars. ■■ A special assembly-focused track on counterfeit components, LEDs and outsourcing costs. ■■ Critical environmental regulations such as developing a systematic approach to compliance and improved environmental performance. ■■ A one-day exhibition, featuring the PCB industry’s leading vendors. ■■ The popular “FREE Wednesday,” including eight free technical sessions. ■■ Networking opportunities throughout the week, from organized coffee breaks to the Wednesday Night Reception, and other events on the show floor. Full details regarding the conference and exhibition are available at Attendees who register for the conference by Aug. 27 will receive a $100 discount on select conference packages. Admission is free for the one-day exhibition and other “FREE Wednesday” events (registration and a badge required). To register or learn more about the show, visit For more information about PCB West, visit or contact Show Manager Alyson Skarbek at 404-665-7749 or

New Parts Library Site Follows ‘Wiki’ Model SANTA ANA, CA – A new user-driven website for creating, managing and sharing 2D and 3D component part and package data is up and running. WikiComponents ( is now online with a select group of beta users. Based on the popular “Wiki” concept, users can build their own part libraries and share them freely with users around the world. Users include those involved in PCB design, PCB assembly and test, as well as mechanical engineers and anyone requiring proper part dimensions and documentation. WikiComponents features a framework for accommodating an unlimited community of users around the world who create, evaluate and improve its content. “Several attempts at providing a universal library for the electronics industry have failed due to the massive resources required to enter the data, says founder Dino Ditta. “These costs must then be passed on to users in the form of high upfront costs or prohibitively expensive ‘pay-per-part’ fees to use the proprietary data. With WikiComponents, data entry is spread among a large circle of users. The result is that everybody benefits, in the form of nonproprietary data, cost savings and an open user policy.” Beta users will be providing feedback on the various aspects of component creation, the component rating system, evaluating existing content and testing the various direct 2D and 3D outputs, including those to various CAD systems, IGES and CAMCAD Pro. The company will work closely with standards committees such as IPC, JEDEC and the EEA for certification, Ditta said. – MB

For the latest news:


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Atlanta Office: 3030 Business Park Drive, #3030-B Norcross, GA 30071 Phone: (770) 446-3116 Fax: (770) 446-3118 Los Angeles Office: 3528 Torrance Blvd., Suite 100 Torrance, CA 90503 Phone: (310) 540-7310 Fax: (310) 540-7930


Circuits Assembly Briefs The UK Smart Group is offering a range of webinars ( to complement its existing training, workshop and seminar program. Webinars of 60 to 90 minutes will be presented by professional engineers, and will cover component technology, PCB manufacture, stencil printing, soldering, cleaning, conformal coating, and other topics. Each student will receive a certificate of participation. The National Labor Committee has released a 30-page report ( reports?id=0602) documenting what it calls illegal and harsh sweatshop conditions at Jabil Circuit’s ( factory in Guangzhou, China, where over 6,000 workers — many of them allegedly illegal temporary workers — manufacture products for HP, Whirlpool, IBM, Intel and Cisco. A Jabil spokeswoman called the report “a very accusatory but not very accurate picture.” Follow us on Twitter: Raytheon ( awarded EMS firm LaBarge ( $3 million in contracts for the JSOW program. A federal court judge has dismissed a lawsuit filed last July by several electronics industry associations against the New York City electronics waste recycling law. Aegis Software ( inked an OEM agreement with Juki Automation Systems Europe ( Sypris ( is partnering with Carnegie Mellon’s CyLab (cylab.cmu. edu) on cyber security research. EMS firm MTI Electronics has closed its Newbury Park, CA, plant. Reno, NV-based contract assembler Paradise Manufacturing has closed, and the factory equipment will be sold at auction. The company was founded as Contract Manufacturing Services in May 1997. Integrated Micro-Electronics Inc. (imiphil. com) and Narra Venture Capital II have signed an agreement to acquire 67% of PSi Technologies (, an independent semiconductor assembly and test-service provider, in a deal valued at $30 million. Top 25 global EMS provider Fabrinet ( went public on June 25, offering some 8.5 million shares of common stock to the public. DEK ( appointed SmartRep distributor in Germany. Marantz Business Electronics (marantz.



Edited by mike buetow

IPC ‘Concerned’ Over Proposed IEEE Environmental Standards BANNOCKBURN, IL – IEEE ( members will soon vote on two proposed standards that set criteria for environmentally preferable electronic equipment, and a competing trade group is expressing concerns over the ramifications. The proposed standards in question, 1680.2 Draft Standard for Environmental Assessment of Imaging Equipment and 1680.3 Draft Standard for the Environmental Assessment of Televisions, will have a broad impact, setting virtual standards for “environmental” electronics throughout the supply chain, as well as establishing precedent for future IEEE EPEAT standards, says IPC. The criteria cover all aspects of the product, from the chemicals contained to how they are disposed. However, the trade group IPC ( is concerned that both standards expand on current RoHS Directive and REACH requirements by eliminating exemptions and removing SVHCs from products; both contain criteria to remove all halogens, including TBBPA; both include a criterion for manufacturers to inventory more than 100 substances in their products; neither requires any assessment of whether restricted substances will or can be replaced with substances better for human health and the environment, and both include a total of 115 criteria. If passed, the standards will become de facto regulations as a result of President Obama’s Executive Order 13514 Federal Leadership in Environmental, Energy, and Economic Performance that requires all government procurement to be certified to EPEAT. The last day to join the balloting group is Aug. 15, and IEEE members can join the balloting group at – CD

OEM Survey: EMS Cost No Longer King MENLO PARK, CA – Product cost is fast receding as the most important factor in the

OEM-EMS relationship, asserts a recent survey of electronics OEMs. The survey of senior operations and supply chain professionals at OEMs ranging in size from $1 million in annual sales to over $100 billion found “significant” yearover-year changes, said Riverwood Solutions (, which conducted the work. The patterns, the consulting firm said, “suggest a shift in thinking by OEMs.” Among the findings: ■■ 14.3% of survey respondents believe that product cost is the single most important performance factor for measuring and managing their EMS provider. In the 2009 survey, more than 41% of survey respondents believed product cost was the single most important factor. ■■ 40.9% of survey respondents are concerned that under-investment by their EMS provider will hurt performance on their account. In 2009 only 25% of respondents were concerned about the level of investment by their EMS provider(s). ■■ 47.6% of OEM respondents say they would be willing to pay their EMS provider 2% more if product returns were cut in half. Affirmative response to this question more than doubled year-on-year, up from just 23.5% in 2009. ■■ 63.6% of survey respondents say they are likely to hire remote operations staff near their EMS provider. Only 29.4% of OEM respondents reported remote hiring plans in 2009. In a statement, Flextronics ( chief executive Mike McNamara said, “The data seem to suggest a shift in thinking from purely lowest cost to one of increased social and supply chain responsibility, and I am encouraged that this will be a positive change for customers, employees and communities. “For years, the users of EMS services could often obtain very low prices for manufacturing services due to pricing structures and operating practices of some industry participants. A fundamental shift has occurred in China, driven by demographic and AUGUST 2010


com/bus/eu) appointed Eltraco to provide exclusive support in the Nordic region. ASYS Group Americas ( named Far West Micro ( representative for ASYS and EKRA products in Oregon, Washington and Idaho. FCT Assembly ( appointed Enterprise Electronic Sales ( as representative for Ohio, Indiana and Kentucky. Orpro Vision ( named Elmatest ( its distributor for Slovakia and Czech Republic. LED lighting provider Bridgelux (bridgelux. com) named Digi-Key ( as a worldwide distributor. Some 30 engineers and photovoltaic manufacturing professionals met June 10 at Flextronics’ Milpitas, CA, campus to form a professional association to advance the photovoltaic engineering and related manufacturing professions. The proposed Photovoltaic Engineering & Management Association would address research, education, industry standards, and training. Delta Group Electronics (deltagroupinc. com) installed a Dage ( XD7600NT X-ray in its Rockledge, FL, facility.

Circuits Assembly People

Edited by mike buetow

economic changes, particularly in southern China, that requires all EMS companies to invest more in their employees. Aside from basic wage increases, employers need to invest more on employees’ health, welfare and living conditions if they want to attract and retain the best employees. This increased focus on social responsibility will undoubtedly increase costs to OEMs, but will inevitably result in greater employee commitment, productivity and quality.” “Some dramatic changes in the distribution of responses to certain questions year-over-year are difficult to explain without some significant external shock to the system,” said Ron Keith, chief executive, Riverwood. “Perhaps the recent deluge of negative press regarding Foxconn that has spilled over onto some of their key OEM customers can explain some of the significant shifts in executive views at key OEM users of EMS services.” – MB

Report: Foxconn to Build Massive Campus in Henan Province ZHENGZHOU, CHINA – Foxconn ( is set to build a 300,000-employee

plant in east central China, according to several published reports. The world’s largest EMS company is in talks with local government officials, who already have allocated land for the new campus. The initial phase will employ 100,000 workers, with some 200,000 more to be recruited in the future. Unnamed municipal authorities said workers will be paid 2,500 to 3,000 yuan monthly, or roughly the same as at the company’s factories in Shenzhen. The government will underwrite the training of the new employees. – MB

MC Assembly Acquires Chase PCB Assembly Business BRIDGEWATER, MA – EMS provider MC Assembly has acquired Chase Corp.’s

TT Electronics Integrated Manufacturing Services named Bruce Richard business development manager for its Rogerstone, UK, facility. He has 10 years’ sales management experience in electronics manufacturing with Exception Group and Future Electronics. iNEMI named Mark Kaltenbach project manager on its HFR-free activities. STI Electronics appointed Harold Breen business development/sales manager. FCT Assembly promoted Katie Powell to regional sales manager, responsible for Canada, the Northeastern US and Texas. She has a bachelor’s from Colorado State University. Precision Valve & Automation named Chris Donham regional sales manager. Torenko and Associates named Don Evans sales engineer.



contract manufacturing services business in a deal valued at $13 million. The deal included all Chase EMS employees, as well as its leased facility in Winchester, MA. MC Assembly now has three sites, including its Palm Bay, FL, headquarters and a facility in Zacatecas, Mexico. It is among the 60 largest EMS companies in the world, according to the CIRCUITS ASSEMBLY Directory of EMS Companies. For the fiscal year ended Aug. 31, 2009, Chase EMS had revenues of $16.4 million and income before taxes of approximately $1.7 million. For the six months ended Feb. 28, the segment had revenues of $10.1 million and income before taxes of $1.2 million. MC Assembly paid $13 million for the unit, a price that will be adjusted upward if net working capital exceeds $4.5 million. Proceeds from the sale will be used for debt reduction and continued investment in Chase's core tapes and coatings businesses. – CD

Canada OK’s Continued Rosin Acid Use OTTAWA – Canada’s Ministers of the Environment and of Health have determined resin and rosin acids will continue to be permitted to be used in manufacturing. The ministers determined that the substances in question do not meet any of the criteria set out in the Canadian Environmental Protection Act of 1999, and gave notice that no further action would be taken on the substances at this time. The substances, which are used in soldering flux, among other products, were under review for toxicity. – MB


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Metals Index

Defense Down Trends in the U.S. electronics equipment market (shipments only).

% Change march aprilr may* YTD%

Computers and electronics products










Storage devices





Other peripheral equipment





Nondefense communications equipment





Defense communications equipment









A/V equipment Semiconductors





Nondefense search and navigation equipment





Defense search and navigation equipment









Medical, measurement and control rRevised.

7/6/09 4/12/10 5/3/10 5/31/10 7/5/10

LME Cash Seller and Settlement for Tin






LME Cash Seller and Settlement for Lead






Handy and Harman $195.60 $269.05 $272.70 $268.75 $260.41 Silver (COMEX Silver) LME Cash Seller and $2.26 Settlement for Copper





Electronic Warfare Systems Market to Top $1.4B by 2015 SAN JOSE – The US market for electronic warfare systems is projected to exceed $1.4 billion by 2015, says Global Industry Analysts Inc. (, as the US upgrades its aging fleet of combat helicopter and tactical combat-aircraft. Systems upgrades and modernization programs are less expensive than overall platform replacement, GIA noted. Defense equipment manufacturers are expected to produce thousands of EW systems, such as electronic countermeasure systems, electronic support measure systems, and radar warning receivers, with production expected to rise significantly over the next 10 years.

-18.5 N/A N/A N/A




*Preliminary. semiconductors. Seasonally adjusted. Source: U.S. Department of Commerce Census Bureau, July 2, 2010

June Manufacturing Growth Slows

Q1 EDA Revenue Up 4.6%

TEMPE, AZ – Economic activity in the manufacturing sector

expanded in June for the 11th consecutive month, according to the Institute for Supply Management ( The PMI registered 56.2%, a drop of 3.5 percentage points. A reading above 50% indicates the manufacturing economy is generally expanding. New orders for the month dipped 7.2 points to 58.5%, while production dropped 5.2 points to 61.4%. Inventories were up a slight 0.2 points to 45.8%, while customer inventories surged 6 points to 38%. Backlogs fell 2.5 points to 57%. ISM said the manufacturing recovery appears to be “solidly entrenched,” but growth is expected to slow in the second half. ISM spokesperson Norbert J. Ore, said, "We are now 11 months into the manufacturing recovery, and given the robust nature of recent growth, it is not surprising that we would see a slower rate of growth at this time. Comments from the respondents remain generally positive, but expectations have been that the second half of the year will not be as strong in terms of the rate of growth, and June appears to validate that forecast.”

SAN JOSE – First-quarter PCB and MCM software sales

fell 8.8% year-over-year to $109.4 million, says the EDA Consortium ( Over the past four quarters, PCB and MCM sales have fallen 8.9%, the trade group said. Overall EDA revenue was $1.25 billion, up 4.6% year-over-year. Sequential EDA revenue declined 1.2%, while over the past four quarters it declined 5.9%.

SIA Unveils Chip Exports Plan SAN JOSE – The Semiconductor Industry Association's

latest policy recommendations ( Publications/Doubling_Exports_Paper_0610.pdf) include doubling funding for basic research at national laboratories and universities by 2016, enacting tax policies that will retain and attract investment in R&D and manufacturing facilities in America, reforming US export controls and streamlining the licensing process, among others.

Industry Market Snapshot feb. mar. apr. may june

Book-to-bills of various components/equipment.








New orders






Semiconductor equipment1


46% 56.2% 58.4% 50.4% 47.6%P 1.06




















Rigid PCBs3 (North America)

1.21 1.13r 1.12P

Customer inventories







(North America)










Computers/electronic products4



4.97 4.87r 4.86P

Sources: Institute for Supply Management, July 1, 2010





Sources: 1SEMI, 2SIA (3-month moving average growth), 3IPC, 4Census Bureau, pPreliminary, rRevised


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EMS’ Rude Awakening Can high-mix, low-volume production succeed in China? You bet.

Carl Hung is vice president - Season Group (; carl. hung@seasongroup. com.


In the 1970s, if you set up a contract manufacturing shop in a good location, customers eventually would walk through the doors. In the real world, things quickly changed for American companies, as OEMs, driven by maximizing shareholder value, searched for cheaper sources offshore. The first options were Hong Kong, Malaysia and Singapore. After prices increased in these countries, greener pastures were found in China. Unfortunately, as the saying goes, all good things must end. Believe it or not, “Made in China” does not mean cheap anymore. Outsourcing to China was a trend that became popular starting in the mid 1990s. At that time, demand for China sources far outweighed the supply, driving up prices. Along the way, China accrued sizable foreign exchange reserves filled with US greenbacks, with the trade deficit between the US and China hitting $226 billion by 2009. With mounting pressure from the US government and the World Trade Organization, China has begun to loosen trade restrictions. It has decided to shift toward manufacturing higher value goods, so the trade deficit “quotas” are not wasted on lowermargin products like Tupperware and toys. China has taken a three-step approach to doing this: First, it has selectively increased import duties on materials used in the manufacturing of low-value products. Second, it has dramatically improved the employment conditions of factory workers by demanding significant increases in paid benefits and minimum wages. Third, it is slowly phasing out free trade zones and licenses. The free trade license, known as san li yi bao, permits companies, many from Hong Kong, to set up production facilities in China without paying any import duties or value-added taxes. The caveat is that all products manufactured must be exported. This was introduced by Prime Minister Deng Xiao Ping in the late ’80s as a means of attracting investments so that the post-Mao Chinese could work in meaningful jobs, as opposed to laboring away on farms. This program certainly succeeded in meeting its goals. China, with a population of 1.3 billion people, is now facing a massive labor shortage. As of February, the China Times reported, the Pearl River Delta area faced a shortage of two million workers. My company, Season Group, is a global EMS provider with a mega-site in Dongguan, among others. Like others in China, we are facing these issues. How do we cope? By being open to change. As Charles Darwin wrote, “It is not the strongest of the species that survives, nor the most intelligent, but the one most responsive to change.” Growing up, I was often discouraged to enter contract manufacturing, as it operates in what some


term a “herd-like mentality.” This means contract manufacturing always goes wherever labor is the cheapest, just as herds do when grazing. Unlike the pastures, though, cheap labor does not return to a country once a higher wage has been set. This means cheap labor becomes scarcer, and all businesses must be prepared for it. When Western OEMs formulate their outsourcing strategy, they must maintain a strict protocol: Low-mix, high-volume (LMHV) work is outsourced to Asia, while all high-mix, low-volume (HMLV) work stays onshore. HMLV is by nature more complex, as the same amount of preparation work needs to be done at a higher frequency when comparing HMLV to LMHV. The characteristics of HMLV work make strong communication between OEM and EMS partners a must, which gets difficult when different languages, cultures and time zones come into play. Here’s where Darwin comes in. Foxconn, the world’s largest EMS provider, has announced a fully automated production facility in Taiwan as a test run. If successful, it will emulate this plant throughout China so that it is not bound by labor shortages. Season will continue to invest internationally as a means of diversifying our risks. Our Penang, Malaysia, facility will be expanded to replicate our China site, with vertically integrated manufacturing capability, including wire harness assembly, PCB assembly, mold and die making, plastic injection molding and plastic thermoforming. This facility provides us with stabilized costs, as wages in Malaysia have not changed much in the past 10 years. Not all products are suitable for offshore production: low-volume, bulky, IP-sensitive, national security, etc. In the near future, there will be a surge of de-sourcing activities in Asia that will result with the production sent back to the US. If you think your current manufacturing strategy is optimal and can last an eternity, be ready for a rude awakening. With economic dynamics changing on a daily basis, no strategy is permanent. Many in the textile industries rushed to Bangladesh in 2009 due to favorable economic circumstances compared to Vietnam; thus, land prices – and subsequently, labor prices – were driven up. Now, with the Vietnamese currency down to 18,885 dong per $1 (from highs of 16,000 per $1), it makes sense to look at Vietnam again. When outsourced assembly work started leaving the US shores for China in the mid 1990s, few thought it would ever come back. The current trend of onshoring proves no strategy is ever safe. CA

august 2010

The Certification Craze Could the alphabet soup of third-party approvals have a deleterious effect? I have a love-hate relationship with the myriad certifications and registrations in our industry, as well as industry in general, that we are expected to apply, achieve, renew and pay for. They range from the now standard ISO family, which encompasses ISO 9001, as well as the closely related but slightly varied AS and QS designations. There is the MIL family of certifications, ranging from the once-dead (but refusing to go away) MILPRF-55110 through an alphabet soup of numeric certifications – all starting with MIL – that cover all aspects of fabrication and assembly. And we can’t forget the granddaddy of them all, UL, which for decades has been the gold standard for reviewing what you do – for a fee. All these certifications are intended to help ensure product quality – and in some cases, service quality – is consistent and topnotch. There are others, too, such as ISO 14000, intended to ensure consistent (and presumed good) environmental and waste system stewardship, and ITAR, really more of a registration, intended to ensure that critical product IP stays in America. The list can seem endless. When the current wave of certifications started to hit our industry over 20 years ago, I viewed them as a great thing that would help individual companies tighten their often individualistic and entrepreneurially managed systems and processes, enabling improved quality and sophistication that customers would appreciate. Equally, I selfishly hoped that by achieving some recognized certification level, the number of annoying customer audits would decrease. But over the past few years, I have started to question where the certification craze may be leading. My questions started when ITAR registration surfaced. ITAR (International Traffic in Arms Regulations) is intended to ensure products, specifically weapon and support systems for national defense and homeland security that have sensitive IP, are produced in facilities that control access to those data and are staffed with US citizens or, for lack of a better term, “legal” workers. In my all-too-often simplistic mind, I thought, Wouldn’t it be easier to demand that such work be produced to MIL spec? But then someone pointed out that some MIL-certified companies may have workers who are not “legal” as defined by ITAR. Hmm, isn’t the implied, if not explicit, purpose of specifying product be built to MIL certification to make sure that critical product and IP are handled and produced to stringent quality and security levels? My concern grew when I began to notice prints from customers with revision levels starting as a MIL-certified part, then revised to IPC-6012, and finally to standard commercial IPC-A-600. More curious and frustrating was hearing from prospective customers that they only august 2010

would approve companies that were ISO/AS/MIL certified and ITAR registered. When asked what type of product they were buying, the response was “commercial built to IPC-A-600.” OK, so you want the certification in place, but don’t need or want product built to it. My final concern came when a customer declined to tour our facility, saying “No thanks; no need to if you are certified to ….” That’s when it hit me that maybe the pendulum has swung too far, or we all have lost sight of what is truly important. Having an independent set of eyes review your facility, processes and data organization is a great thing. You always learn how you might improve, get a different view as to how things might flow better, and (hopefully) receive confirmation that your process management efforts are paying off in consistent, auditable quality performance. Striving to reach the next level via a new certification can be a great motivator – a goal to which everyone can aspire. Reaching to attain AS 9100 on top of ISO 9001, or going for MIL-PRF-31032 rather than staying with the outdated MIL-PRF-55110, can result in further refining processes, tightening key manufacturing and inspection protocol, and offering everyone involved a sense of pride. As good as it can be, however, often overlapping certifications and lack of customer commitment to supporting certifications by purchasing to them can be more than a little frustrating. If government is concerned with IP security, it should add a clause to the various MIL certifications they profess to support and then demand their suppliers purchase to that certification level when the application demands that level of security and quality. Conversely, if ITAR appropriately handles the IP concerns, and ISO likewise does for product quality and conformity, then maybe it’s time to do away with the MIL certification process altogether. Currently a number of well-intentioned efforts are underway to develop various protocols – certifications – that could impact our industry. Whether revolving around the current hot button of IP management or dealing with supply-chain materials management due to ever-tightening environmental concerns, such as RoHS, all need to be considered carefully, so we as an industry do not regulate ourselves to death. Certifications that encourage process or continual improvements are good. But we need to demand that, wherever possible, such enhancements be incorporated into an existing certification hierarchy and not reason to create an entirely new and redundant certification. Time and treasure should be utilized in the most efficient way possible for each company and the industry, and not to fuel a regulatory agency and the consultants they breed. PCD&F

Peter Bigelow is president and CEO of IMI (; pbigelow@imipcb. com. His column appears monthly.




Outsourcing’s X-Factor Costs The risks of assuming one size – or company – fits all.

Susan Mucha is president of PowellMucha Consulting Inc. (powellmuchaconsulting. com), and author of Find It. Book It. Grow It. A Robust Process for Account Acquisition in Electronics Manufacturing Services; smucha@powellmuchaconsulting. com.


The recent media frenzy over the suicides at Foxconn’s China campuses generated valid observations on social stresses in China, but also spurred incorrect generalizations about outsourcing and the electronics manufacturing services industry. Without commenting on the Foxconn situation in particular, here I consider the potential considerations it adds to the outsourcing equation, and why I don’t think it appropriate to assume that issues or practices at one EMS provider reflect practices across the entire industry. In April in this space, I looked at ways EMS providers in Singapore, Poland, Mexico and the US invest in employee quality of life initiatives. As someone who has spent 20 years working in EMS factories and another nine consulting to them, I strongly believe that corporate focus on employee quality of life initiatives pays for itself in reduced turnover, stronger employee commitment to building quality products, a better educated workforce, “hands-on” feedback in continuous improvement initiatives, and lower costs for recruitment, absenteeism and health care. The April column touched on a few examples, but there are many more within EMS. No question EMS is a low-margin industry, and EMS providers tend to be near the bottom of the wage scale in their respective markets, but many still find a way to treat employees with respect and provide upward mobility for employees interested in additional training and advancement. Outsourcing carries both measurable and hidden costs. In the best-case scenario, these hidden costs are inefficiencies in working relationships, learning curve in product transfer, or minor quality

issues that require onsite source inspection to rectify. Worst case, there can be an x-factor cost that far outweighs any cost differences between EMS providers. In the Foxconn scenario, that turned out to be damage control wage increases, compensation to families and media relations activities. Does this mean all outsourcing carries unacceptable risk? The answer is, not if OEM sourcing teams balance their numbers with common sense. There is wide variety in the EMS universe, and associated tradeoffs and risks in choosing a particular supplier need to be carefully considered. Is Foxconn a bellwether of future issues within the industry? Foxconn is atypical of the contract manufacturing industry as a whole, in terms of sheer size, business origins and business mix. However, the issues experienced are ones any company manufacturing at that scale in a low-margin environment could encounter. Is this a sign that China is a bad place to source? While rising labor costs and labor unrest in China are making headlines, it is a natural dynamic of rapid economic growth. I talked to a lot of production workers during the 20 years I worked in the EMS industry, including some in Shenzhen. There isn’t a lot of difference between the dreams and aspirations of a production worker in China from those in the US. But as low-cost labor markets become popular, cost of living often rises faster than wages, and those dreams become harder to achieve. Add in conspicuous consumption by people at the higher end of the wage scale, and you create a fairly volatile situation. Further, what is happening in China may eventually happen in India or Vietnam, or any of the other emerging labor markets being considered as “China alternatives.” To better understand the tradeoffs and potential x-factor costs inherent in selecting a given low-cost labor market, it is important to understand labor market evolution. Low-cost labor markets tend to evolve from emerging regions where low-cost, low-skilled labor is used for easyto-source projects with lower quality requirements, to established low-cost labor regions with a mix of automation and labor, and finalFigure 1. Advantages and disadvantages of low-cost labor markets.


august 2010

FOCUS ON BUSINESS ly to mature low-cost regions where cost competitiveness is derived from a combination of productivity enhancements in a highly skilled workforce, balanced with access to lower-cost regions. As Figure 1 illustrates, there are potential x-factor risks and tradeoffs with each type of market. While emerging and established regions offer potential for cost reduction, they may be lacking in support for schedule flexibility or product development support for new technologies. These markets are also undergoing the highest rate of socioeconomic change, so they also have the potential for x-factor wage inflation or workforce unrest. Comparatively, a mature labor market offers a supply base that can tap a highly skilled workforce for complex projects and source in emerging and established low-cost labor regions for projects with less complexity. But while a mature market may have less hidden cost, it may be noncompetitive for high-volume, margin-sensitive product. The best choice in labor markets depends on a range of factors, including project volumes, complexity, product end-market, margin pressure and demand variability. Consider this scenario: Your product has an annual volume of 20,000 units per year. The corporate edict on sourcing insists all manufacturing go to an established low-cost labor market such as China. You get a quote. The price is $1/unit lower than you find in neighboring mature low-cost labor markets, so you source with that provider. You’ve saved $20,000. However, quality problems require onsite source inspection for three weeks. Your low-volume project is the least important priority in the production area, so frequent late deliveries also add hidden costs. A key member of your team quits because his family is unhappy about the overtime he is working because the contractor doesn’t have program management in the same time zone. By the end of the year, you haven’t saved any money. And, this example doesn’t include any x-factor surprises such as a product recall, unanticipated work stoppage or a flu outbreak. On the other hand, if you saved $1/unit on a product with a 1 million annual quanaugust 2010

tity, the typical hidden costs would be easily absorbed. X-factor cost would still be a risk that would need to be evaluated, but the overall savings would probably justify the risk if the contractor audited well. No EMS provider is the right solution 100% of the time. However, the EMS industry offers a wide range of options that can represent the best solution for a specific project. Sourcing

teams that carefully evaluate measurable costs, supplier internal “culture,” the suppliers’ support infrastructure for their unique project requirements, and overall trends in preferred country build site will minimize the potential for both hidden and x-factor costs. Conversely, sourcing teams that focus solely on squeezing every penny out of the unit price increase their risk for an x-factor surprise. CA

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In a Flash From Fremont to Tunisia, AsteelFlash aims to be a worldwide Tier 2 EMS. It was among the largest EMS mergers of the

decade, but the timing – just a few days before Christmas 2007 – may well have distracted from the enormity of the event. On Dec. 20, Asteel announced its acquisition of Flash Electronics in an all-stock deal, forming an EMS company with more than $600 million in annual sales. Today, Paris-based AsteelFlash ( has 12 manufacturing locations on four continents, and continues to make the occasional strategic acquisition, having acquired MRP in the UK in 2008. Georges Garic, corporate vice president and general manager of  America and Asia, spoke with Circuits Assembly’s Mike Buetow in July about the company’s strategic approach – and its atypical footprint. CA: Asteel has 12 sites worldwide, but compared to some of the large EMS companies in the world, they are not in all the usual places. Do you see that changing at all over the next two years? GG: Asteel and Flash Electronics created AFG in February 2008. Our strategy is to become a worldwide Tier 2. We want to differentiate ourselves by the proximity, the footprint, the technology and our supply chain. We are planning to acquire something in Mexico, and on the East Coast in the US and in some other countries in Europe. The proximity [to customers] is important. CA: In some company literature, Asteel presents itself as a high-mix, low-volume company. GG: When we analyzed the market, we saw all the Tier 1s merging and becoming bigger, and customers were coming to us and complaining about service problems for the high-mix, lowvolume markets. When it’s high-volume, low-mix, it’s easy to run with the Tier 1s. When it’s high-mix, it’s another story. CA: Could you break down the percent of revenues from low-mix, high-volume vs. highmix, low-volume? GG: Today, high-mix, low-volume is about 60% to 70% of revenue. CA: What is a typical lot size? GG: One hundred to 200 boards would be a big batch. CA: Break down Asteel’s end-markets by sales percentage. GG: We are trying to balance the markets: networking infrastructure, storage, industrial, RF, and lighting. CA: Why are those ideal markets for the company today? 20


GG: It’s linked to our history and footprint. California is heavily in networking and storage. In Europe, it’s heavily industrial. So due to the history of the two companies, we are strong in those areas. Other areas we are trying to develop are military/ aero – we are now ITAR registered in our Fremont, CA, plant – and medical, so we can expand. We also are working on solar, which we group under industrial. CA: Among your sites are two in Tunisia. Are there differences to manufacturing in North Africa vs. other locations? GG: Tunisia is to Europe what Mexico is to North America. It is stable and low-cost. There are a lot of companies there from Europe: Spain, Germany, France, Italy. Among EMS companies however, none from the Tier 1 is there. After us, there are companies in the $20 million to $50 million range. There is a clear stability of costs that you don’t have in Eastern Europe. We saw all the costs in Eastern Europe skyrocket. Tunisia has stability in the wage rate and the exchange rate of the dinar to the euro. And it is one hour from Europe by plane. CA: As of 2008, you had sales of $608 million. Where does that stand today? GG: At the end of this year, we will be ahead of our 2008 revenue. CA: Have you encountered problems with parts availability? GG: Everyone has the problem. We have heat on lead times and prices. I don’t know when the end to this crisis will be. It started in the fourth quarter (2009); I think we will suffer through the end of this year. But we don’t see any more huge expansions of lead times. Our backlog is clearly increased. I think there is a potential small bubble effect of this backlog. We are spending a lot of energy and have some negative heat because of prices. CA

Man of Asteel: Garic august 2010


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Waking Up in PCB Wonderland Why standardization only goes so far. Take a little trip with me to PCB Wonderland. PCB Wonderland is where all parts fit on the board; all component footprints and land patterns are perfect, and the design is finished on two fewer layers than the budget called for. In PCB Wonderland the design data are spot-on and exactly what the fabricator needs to get 100% yields. The bare boards are completely in spec and delivered a day early. At the assembly house all the parts are in stock by the time the boards arrive and, again, the yield is 100%. All the finished assemblies pass test and are delivered early. In PCB Wonderland the design team gets a nice big bonus and a week off with pay for a job well done. WAKE UP!

development of excellent calculators and industry brain trust specifications, land patterns are still a problem. While there may or may not be issues with the calculators or specifications themselves, there are other unforeseen variables. Take the component package itself. While component manufacturers standardize on package sizes and outlines through Jedec and similar organizations, one manufacturer’s “standard” package may in fact differ from what is presented by another manufacturer as the same component package, or it may be a case that the parts are counterfeit or otherwise not to specification. Sometimes it’s a process issue. Every contract manufacturer has subtle or not-so-subtle differences in their processes (just like every designer, fabricator and EDA tool has different processes). One interesting suggestion was that if the paste were left unrefrigerated too long, it could Even with calculators and industry standards, make a difference in how it prints and reflows, land patterns remain a problem. and thus, the part could tip. I would never have thought of that. In the end, I have to recognize that the goal of perfection in this context is laudable, Sorry to do that to you, but the little trip down but probably impossible to achieve. There are just the rabbit hole is what happened when I dozed off in too many variables involved and too many processes the middle of Alice In Wonderland a couple nights from start to finish. But we can focus on our area ago. I finally realized it was just a dream when the of execution, educate ourselves as best we can (for guy who delivered the product turned out to be example, at PCB West in September;, Johnny Depp in a top hat. and get involved in all of the process to the maximum I’ve heard (or read somewhere) that our dreams extent possible. Designers still are accused of throware usually influenced by something going on in our ing stuff over the wall. It happens before the design is lives. It may be a problem without an immediately done, and it happens after the design is done. While obvious answer (I remember actually solving a routI’d like to take the designer’s side of every argument, ing problem in a dream) or something that is stuck in I can’t always do that. I hear it too often from too a region of the brain dealing with the subconscious. many sources for it to be nothing more than a conIn this case, it may have been that I had been thinkvenient excuse. ing about component tombstoning. After reading an I suppose it is too much of a stretch to think that online post about causes of components not doing component manufacturers, design and manufacturing what we intend them to do – in this case, settling can come together to develop real standards, versus their little selves onto the assigned pads and staying “recommendations”– the kind of standards that there – I’d been doing some research on the subject. I everyone in the supply chain would adhere to and will admit that my research was not at the level of a that could help ensure everything would go smoothly. Pete Waddell doctoral thesis, but after reading several articles and But I suspect those only exist in PCB Wonderland. is design technical talking to some experts in the field, I’ve come to the Stay in touch. PCD&F editor of PCD&F; conclusion that there are more causes for the problem pwaddell@ than there are words in this column (regarding the latter, about 750). First, I asked whether tombstoning is as much a problem as I suspected. The overwhelming answer: a resounding “YES.” Next, I asked the age-old query of every 5-yearold: “Why?” The first response was another question: “How much time do you have?” The causes piled up like Lindsey Lohan’s police reports. Even with the 22


august 2010


Bogatin’s Rules Ten lessons from 25 years of teaching electrical design. 6. Sometimes an OK answer NOW is better than a good answer later. You often have to make decisignal integrity topics for more than 25 years. I’ve sions without all the information you would like. taught more than 7,000 engineers and personThis is where rough estimates are important. What ally mentored more than 30. Along the way, I’ve is the bandwidth of an 800 Mbps DDR3 signal? It developed some sayings that crystallize important depends on the rise time, of course, but if you don’t rules to consider when working on signal integrity know the rise time, do you sit and wait until someprojects. Of course, these rules apply to more than one can measure it? If you need an answer NOW!, just signal integrity. you can use the rule of thumb that the bandwidth I received a note from a recent student who jotted is about the 5th harmonic of the clock. The clock is down my “rules.” He sent me a copy. This month, I 400 MHz and the 5th harmonic is 2 GHz. thought I would share some of the list: 7. Always evaluate the bang for the buck from a 1. The most common answer to all signal integrity design change using a “virtual prototype.” This is questions is “it depends.” And, the way to answer a parameterized model for your system, and a way all “it depends” questions is by “putting in the of simulating its performance using this model. It numbers” using rules of thumb, approximations, will help you answer “what if” questions, and lets numerical simulations and measurements. you measure the expected performance gain for the 2. The way to separate myth from reality is by extra cost of a new material, design or component, “putting in the numbers,” using rules of thumb, before you commit to hardware. approximations, numerical simulation tools and 8. Watch out for “mink holes.” A rat hole is a conmeasurements. All these processes are equally voluted path you detour down that takes away important and should be in the tool box of from the real goal. A mink hole is a rat hole lined every engineer. They each have a different balin mink: It feels really good while you are in it. ance between accuracy and cost to get an answer Engineers love technical puzzles. Resist the tempta(cost as measured by time, money and expertion to track down every little detail, or get that tise). Use the process for each problem approprimodel bandwidth to just another few GHz. More ate to your budget. important problems are always awaiting attention. 3. Watch out for the “Whac-a-Mole” effect. Often, changing one design feature to improve a performance Never perform a simulation or measurement metric has a negative impact on another performance metric. It is like without anticipating what you expect to see. the Whac-a-Mole arcade game. For example, bringing the signal path closer to the return path decreases 9. Never perform a simulation or a measurement ground bounce, but at some point, this will reduce without anticipating what you expect to see. If you the impedance of the interconnect and cause excesare wrong, something is off in the problem setup, sive reflection noise. the tool accuracy, or your intuition. Either way, 4. The most efficient way to solve a signal integrity you will learn something by tracking down the problem is to find its root cause. If you don’t know discrepancy. If you are right, and you see what you the root cause of a problem, and it goes away when expect, you get a nice, warm feeling that maybe you try something, you have no idea if this was a you really do understand what is going on. coincidence or if this problem will creep back in. 10. There are two kinds of engineers: those who have 5. Use the Youngman Principle to turn a root cause signal integrity problems and those who will. The into a design guideline. This is named after Henny corollary is, there are two kinds of designers: those th Youngman, a famous comedian of the 20 Century. who are designing antennae on purpose and those One of his jokes was, “A man goes into a doctor’s who aren’t doing it on purpose. office and says, ‘Doctor, my arm hurts when I raise

I’ve been writing about, lecturing and teaching

it. What should I do?’ The doctor replies, ‘Don’t raise your arm.’ ” If design feature A causes problem B, to eliminate problem B, eliminate design feature A. For example, if reflection noise is caused when the instantaneous impedance the signal sees changes, engineer the instantaneous impedance to be constant down the entire interconnect. august 2010

Eric Bogatin, Ph.D., is a consultant and founder of Be The Signal (bethesignal. com); eric@ His column runs periodically.

Additional rules and many of their details are covered in papers available for free download at PCD&F



Second Source Need Not be Second Rate Properly applied DfM mitigates component package tolerances.

Max Clark is product marketing manager, Valor Division, Mentor Graphics (mentor. com); max_clark@


You may have been here: John and Sally did the design and PCB layout for their company’s popular new product. It was, in fact, so popular, many of the primary-source components cannot be procured in the quantity necessary, so backup sources have begun to be used. And that’s when the trouble began. Instead of the high yield they had been achieving, there were failures and, worse, intermittent problems began to surface. After a great deal of time investigating the cause, they discovered one of the components supplied by a secondary supplier was not quite mechanically equivalent. Unlike the initially sourced part, the solder points did not line up in the center of the lands. This can happen with any product. However, very popular products that run for a long time are more likely to have to use second- or third-source parts over the run of the product. And, of course, a long-running, popular product is the last one in which you want to have quality problems arise. When a designer uses a land pattern for a singlesourced component, such as a programmable part, SoC, etc., the chance for subsequent manufacturing problems, due to the component not precisely matching the lands, is virtually zero. Lands were specifically designed for that, and only that, part. On the other hand, commodity-type parts are almost always multi-sourced, and not all suppliers have precisely the same component geometry. Here’s a real-world example: Figure 1 shows the contacts area of one possible component placement. Notice the size of the left and right distance present to supply enough solder on each side of the pin. In this example, the preferred component’s contacts fit neatly into the center of the lands generated from library data. Even if the component were slightly misplaced or dislodged, there is a cushion. Such margins enhance manufacturability and minimize rejects. In Figure 2, a second-source component placement has been superimposed over the primary-source component. The cyan color represents the original component, and the magenta color represents the portions of the second-source component that extend beyond the bounds of the primary-source component. This part is now encroaching on the edges of the lands. Because the contact points take up greater area on the land, less solder is available to form an acceptable pin filet. While the component in this illustration may not produce manufacturability problems, in more extreme cases, contact points might take up too much area, or be near or off the edge, which can result in serious quality problems.


Figure 1. With the preferred component, the contacts fit right in the middle of the lands.

Figure 2. An alternative part (magenta) overlays the original component (cyan). Notice the second options begin to encroach on the left, right and top part of the land pattern–and through, reducing the amount of solder to form the left, right and pin fillets.

Rather than find out you have a problem when production yields take precipitous plunges, incorporate DfM practices early in the design process to ensure all possible components will be accommodated by the land patterns in the design library. (This, by the way, can be automated.) On the horizon are tools capable of automatically generating an “envelope” that fits all available components. Then, the envelope is compared to the land patterns. Using the envelope approach ensures every possible component that can be sourced for this product will fit and pass a solderability test. This problem is just one that can be addressed with DfM techniques and tools. In the future, I will illustrate other DfM techniques for PCB design. PCD&F august 2010

material management

Benefits of Factory



Optimal cost management means material prepped for production needs real-time monitoring on the factory floor. by Jay Gorajia

Manufacturers deploy various manufacturing systems that provide necessary controls, enable data collection, support cost-saving initiatives, provide a means for compliance, and help decrease time to market. Yet most remain as islands of information, and provide the value intrinsic within their own confined systems. How can real-time material management manage costs and improve inventory turns? What are the benefits of having a quality system talk to a traceability and material management system? Can we optimize overall equipment effectiveness by enhancing links between material flow, quality and surface mount technology programming, and monitoring data? How can we increase revenue? The typical organization likely has purchased and deployed various manufacturing systems, either based on customer requirements or internal process improvement initiatives. Those systems have been painfully deployed, causing all kinds of havoc to existing operating processes and risks to quality. Now that the tough deployment is done, and systems seem to be running fine, how is this leveraged to improve business? Can the organization better compete in the EMS manufacturing world using these manufacturing systems? Let’s review the systems typically deployed at EMS and vertically integrated manufacturing companies. A quality management system (QMS) ensures that product quality is collected and monitored through the assembly process. At key inspection points in the factory, operators visually review a board, scan or enter board identifiers (serial numbers or barcodes), and a defect code that reflects the issue with that board. Those data are collected for each board and pushed into a database for mining later. The value of those data depends on the capabilities and limitations of the solution, the creativity of the team, and how those data are mined. Good business intelligence solutions are most effective at this point, and should not be confused with manufacturing intelligence (focus on overall manufacturing visibility of key aggregated data/metrics for upper management). The main goals of QMS are yield rates (first pass, order, absolute); defects per million opportunities (DPMO); DPM per assembly, order, and functional area on the production floor; storing historical data for trend analysis and post-moraugust 2010

tem root cause analysis; ensuring on-time shipments (no production stops due to rework); performing preventative and corrective actions; maintaining and ensuring conformance and compliance, and providing statistics for OEE. Manufacturing operations management (MOM) systems control and ensure boards move in a predefined path on the factory floor and at each of these locations. Board information is recorded to ensure work in process is registered and monitored. A shop-floor system answers the following questions: Was the correct SMT line used? Was it handed off to the right manual insertion line or stations? How many boards of a specific work order are in test or final QA? How long did it take? How much inventory was used, and when? Did the product go down a RoHS-compliant line? Some systems also include traceability. Which part numbers are placed on a board is added to the information and used to create a build record for that order and/or assembly. Enterprise resource planning systems are complex systems that handle purchasing, order management and planning functionality within manufacturing companies. The ERP provides the information on what needs to be built (work order), the quantity to be built, and the parts to use (bill of materials, company-specific part numbered lists). ERP systems also manage available inventory to ensure the correct amount purchased, and, at production order completion, that the customer is shipped to, invoiced or billed. You’ve implemented a QMS, an ERP and even a shopfloor system or full MOM. Now what?

Interoperating to Manage Cost Cost management is tied to factory management. Key cost contributors in most factories include material use, rework, returns and overstock. Interoperating systems that “talk to each other” help manage costs. The largest variable cost in manufacturing is the material. Purchsed raw material (components) sitting in stock depreciates in value. Material sitting on the factory floor costs money and goes into a void, where only regular inventory counts, or manual material counts, bring them back into view – typically, too late to make any adjustments PRINTED CIRCUIT DESIGN & FAB / CIRCUITS ASSEMBLY


material management

before diminishing inventory turns. You can completely eliminate the problem of material shortages on the production floor. What if you knew exactly how much material is needed? The average factory sees about five material shortages per line per week, according to a study by the Aberdeen Group (Table 1). While that material is being pulled, production is stopped, adding to the opportunity cost. To truly achieve cost management, material pulled out of stock, kitted and prepared for production, needs to be monitored real-time on the factory floor. As feeder errors, nozzle rejects, and drops add to the consumption of the material issued, the stock room needs to be alerted and advised of materials needed (like part numbers), and the stock and delivery location (line and machine). Only if an SMT monitoring system is interoperating with a material management solution in real-time (which polls the consumption and generates these material pull instructions) can this be achieved. Knowing that a part will be out is not enough. An alert when material is out in a machine or feeder provides no additional value. In most cases, that’s the status quo. If the monitoring system provides low-level warnings that a part will be out after five or 10 additional boards, then we truly can react in time to provide mate-

rial: This is a predictive solution. Material management is complex and essential, with several factors to consider. Material availability rules can be modeled in a cost methodology. It may be more expensive to pull some parts from stock over others. Pulling inventory should be done using a first-in-first-out approach, so oldest parts are pulled first; older parts are cheaper. Inventory issued to production that sits in floor stock is cheaper than inventory in a main warehouse. Moisture-sensitive parts sitting in dry ovens or dry storage locations must be considered. If they are not ready to be pulled from storage, they are not available. This costing model must be part of the material management system, interoperable with the SMT monitoring system to effectively pull the right parts to the right locations just in time. How best to execute this process of costing? Will the warehouse or material handlers know what to do, when and to where? A communication mechanism must be created to eliminate errors and maintain process quality. The material management system should poll the SMT monitoring system at regular intervals and generate a picklist. Polling can be configured based on production rates, production line size and the frequency of expected material requirements, so the consumption data are queried and a

picklist is generated when needed. This picklist will alert the material handler to pull the appropriate material from their stock locations (production floor stock, raw material warehouse, etc.) by generating a barcoded or paper picklist used to fullfill the order. Once material is ordered, it is routed to the production floor for use. For high-volume continuous production, picklists and material arrivals can be done at regular intervals to ensure production lines are never starved for material. Production stoppage due to material shortage is no longer an issue. For vertically integrated manufacturers or EMS companies that produce high-mix with high volume, the challenge is to ensure material is ready and constantly available, and between work orders (with 75% similarity in parts), plus minimize the changover downtime. Changeover is the process of preparing an assembly line for a new production order. In most cases, this means changing conveyors, NC programs, documentation, active order selection and material. Typically, variant products are built on the same line so they can avoid changing the conveyors, thus replacing only the materials and programs associated. However, this poses a new problem: how to change all the materials (feeders, reels, bins, trays) efficiently. The answer: interoperability between material management and SMT monitoring.

Table 1. Average Factory Performance Metrics Definition of Maturity Class

Mean Class Performance

Best in Class: (top 20% of aggregate performance scorers)

■■ On-time delivery at 96% with a 14% improvement year-over-year ■■ Throughput at 93% with an 8% improvement year-over-year ■■ Stock outs at 3 averaged per line per week with a 37% improvement year-over-year ■■ Direct material usage variance at 2.9% with a 50% improvement year-over-year ■■ OEE at 60% with a 9% improvement year-over-year

Industry Average: (middle 50% of aggregate performance scorers)

■■ On-time delivery at 93% with a 9% improvement year-over-year ■■ Throughput at 89% with a 2% improvement year-over-year ■■ Stock outs at 5 averaged per line per week with a 29% improvement year-over-year ■■ Direct material usage variance at 4.1% with a 17% improvement year-over-year ■■ OEE at 65% with a 5% improvement year-over-year

Laggard: (bottom 30% of aggregate performance scorers)

■■ On-time delivery at 80% with a 5% decrease year-over-year ■■ Throughput at 84% with a 0% improvement year-over-year ■■ Stock outs at 7 averaged per line per week with a 21% improvement year-over-year ■■ Direct material usage variance at 28.2% with a 47% decrease year-over-year ■■ OEE at 57% with a 5% improvement year-over-year

Source: Aberdeen Group



august 2010

material management

The SMT monitoring system (machine vendor or third-party) has knowledge of part number location (or where they need to be located), and at which slot/feeder on the machine. It contains the program information, which program is active, and defines which one is next. Knowing this and pulling the information ordered by the picklist generator, changeover instructions can be created easily. The only way to ensure the right changeover instruction is generated is by using the actuals on the machines (Figure 1), rather than planned by engineering. Real-time changes happen all the time in factories. To achieve efficient changeover, correct material must be available, and only the changes should be done; excess material or time spent is waste. Knowing where all material is at any time increases productivity and cost efficiencies. Pulling material as it is needed, and not over-pulling, adds additional efficiency into the process. Reduction of WIP and faster material movement increase productivity and

inventory turns. This focuses manpower on productive tasks, further managing costs.

Managing Rework and Quality After implementing the material manager solution, the material handling, inventory and changeover efficiency issues are handled. But there are other places where costs are hidden: quality returns and rework. Rejected boards from in-circuit testers, flying problem testers, functional test units, even manual inpection stations: All need further troubleshooting and fixing. If an unexpected rework has been identified, and the volume increases, it puts stress on the whole ecosystem. Are there enough replacement components to rework those boards? Is certified manpower available to perform that rework? Will we hit the due date for that customer order? QMS should be able to alert management if accceptable quality levels are not met in real-time. It is too late if AQL breaches are found in post-

Figure 1. Robust changeover reports and instructions for SMT machine setups can result in faster material movement, and productivity and inventory turn increases. august 2010

mortem analysis. Alerts should be set up as escalation of notifications for many of the following: the number of repair loops met (e.g., three test and repair loops maximum per board); AQL; first-pass yield percentage; consecutive failure of the same type. If QMS and material manager are interoperating, evaluating the inventory of the required components and pulling the required material to the rework stations as needed can be done. In post-mortem analysis, if the QMS identifies a high failure or defect count on a specific component location on an assembly, that information can be tied to the material manager to find the specific vendor, part number, and lot for additional supply-chain quality analysis. Using the QMS and material manager to identify quality problems during production is the most efficient way of managing costs before the costs occur. Overall equipment effectiveness is determined by the availability, performance and quality percentage parameters. As material is delivered to production equipment and stations as needed, the performance metric is greatly improved due to the lack of stoppage from starvation. As QMS interoperates with SMT monitoring and shop-floor systems, quality defects found in inspection stations (automated and manual) can be traced back to their source assembly machines, and further analysis of the root causes can be performed. Some examples of these include nozzle problems, high feeder errors or machine uptime issues. Most manufacturing plants have deployed manufacturing systems. When those manufacturing systems talk to each other, much higher value can be realized. If a completely integrated manufacturing system solution is available, the benefits described of managing costs and improving customer satisfaction can be realized out of the box. PCD&F

Jay Gorajia is the support manager for the Mentor Graphics Valor Division; PRINTED CIRCUIT DESIGN & FAB / CIRCUITS ASSEMBLY


electrical test

Capacitor Testing

Challenges and Solutions Chip caps are prone to leakage, so consider these test methods for minimizing electrical failures. by Dale Cigoy

Capacitors are widely used for bypassing, coupling, filtering and tunneling electronic circuits. However, to be useful, their capacitance value, voltage rating, temperature coefficient and leakage resistance must be characterized. Although capacitor manufacturers perform these tests, many electronics assemblers also perform some of these tests as quality checks. This article looks at some of the challenges associated with capacitor testing, as well as some of the test techniques used. A capacitor is somewhat like a battery in that they both store electrical energy. Inside a battery, chemical reactions produce electrons on one terminal and store electrons on the other. However, a capacitor is much simpler than a battery because it can’t produce new electrons – it only stores them. Inside the capacitor, the terminals connect to two metal plates separated by a non-conducting substance known as a dielectric. A capacitor’s storage potential, or capacitance, is measured in farads. A one-farad (1 F) capacitor can store one coulomb (1 C) of charge at one volt (1 V). A coulomb is 6.25´1018 electronics. One amp represents a rate of electron flow of 1C of electrons per second, so a 1 F capacitor can hold one amp-second (1 A/s) of electrons at 1 V. The coulomb’s function of an electrometer can be used with a step voltage source to measure capacitance levels ranging from <10pF to hundreds of nanofarads. The unknown capacitance is connected in series with the electrometer input and the step voltage source. The calculation of the capacitance is based on this equation:

to zero the instrument. When zero check is enabled, the input of the electrometer is a resistance from roughly 10 MΩ to 100 MΩ, depending on the electrometer used. Zero check should be enabled when changing conditions on the input circuit, such as changing functions and connections. The REL function subtracts a reference value from actual readings. When REL is enabled, the instrument uses the present reading as a relative value. Subsequent readings will be the difference between the actual input value and the relative value.) Then, the voltage source should be turned on and the charge reading noted immediately. The capacitance can then be calculated from:

(Eq. 2)

where Q2 = final charge Q1 = initial charge (assumed to be zero) V2 = step voltage V1 = initial voltage (assumed to be zero) After the reading has been recorded, reset the voltage source to 0 V to dissipate the charge from the device. Before handling the device, verify the capacitance has been discharged to a safe level. The unknown capacitance should be in a shielded test fixture. The shield is connected to the

(Eq. 1) Figure 1 illustrates a basic configuration for measuring capacitance with an electrometer with an internal voltage source. The instrument is used in the charge (or coulombs) mode, and its voltage source provides the step voltage. Just before the voltage source is turned on, the meter’s zero check function should be disabled and the charge reading suppressed by using the REL function to zero the display. (The purpose of zero check is to protect the input FET from overload and 28


Figure 1. Capacitance measurement using an electrometer with an integrated voltage source. august 2010

electrical test

Figure 2. A simple capacitor leakage test circuit.

Figure 3. Alternative test circuit that incorporates a smallsignal diode.

LO input terminal of the electrometer. The HI input terminal should be connected to the highest impedance terminal of the unknown capacitance. If the rate of charge is too great, the resulting measurement will be in error because the input stage becomes temporarily saturated. To limit the rate of charge transfer at the input of the electrometer, add a resistor in series between the voltage source and the capacitance. This is especially true for capacitance values >1 nF. A typical series resistor would be 10 kΩ to 1 MΩ.

the capacitor becomes shorted. Second, the decreasing reactance of the capacitor with increasing frequency will increase the gain of the feedback ammeter. The resistor limits this increase in gain to a finite value. A reasonable value is one that results in an RC product from 0.5 to 2 sec. The switch (S), while not strictly necessary, is included in the circuit to allow control over the voltage to be applied to the capacitor. The series resistor also adds Johnson noise – the thermal noise created by any resistor – to the measurement. At room amps, p-p. The temperature, this is roughly 6.5×1010 current noise in a 1 TΩ feedback resistor at a typical 3 Hz bandwidth would be ~8×10-16 A. When measuring an insulation resistance of 1016Ω at 10 V, the noise current will be 80% of the measured current.

Capacitor Leakage Leakage is one of the less-than-ideal properties of a capacitor, expressed in terms of its insulation resistance (IR). For a given dielectric material, the effective parallel resistance is inversely proportional to the capacitance. This is because the resistance is proportional to the thickness of the dielectric, and inverse to the capacitive area. The capacitance is proportional to the area and inverse to the separation. Therefore, a common unit for quantifying capacitor leakage is the product of its capacitance and its leakage resistance, usually expressed in megohms-microfarads (MΩ·µF). Capacitor leakage is measured by applying a fixed voltage to the capacitor under test and measuring the resulting current. The leakage current will decay exponentially with time, so it’s usually necessary to apply the voltage for a known period (the soak time) before measuring the current. In theory, a capacitor’s dielectric could be made of any non-conductive substance. However, for practical applications, specific materials are used that best suit the capacitor’s function. The insulation resistance of polymer dielectrics, such as polystyrene, polycarbonate or Teflon, can range from 104 MΩ·µF to 108 MΩ·µF, depending on the specific materials used and their purity. For example, a 1000 pF Teflon cap with an insulation resistance higher than 1017 Ω is specified as >108 MΩ·µF. The insulation resistance of ceramics such as X7R or NPO can be anywhere from 103 MΩ·µF to 106 MΩ·µF. Electrolytic capacitors such as tantalum or aluminum have much lower leakage resistances, typically ranging from 1MΩ·μF to 100 MΩ·µF. For example, a 4.7 µF aluminum cap specified as 50 MΩ·µF is guaranteed to have at least 10.6 MΩ insulation resistance. Capacitor leakage test method. Figure 2 illustrates a general circuit for testing capacitor leakage. Here, the voltage is placed across the capacitor (CX) for the soak period; then the ammeter measures the current after this period has elapsed. The resistor (R), which is in series with the capacitor, serves two important functions. First, it limits the current, in case august 2010

Alternate test circuit. Greater measurement accuracy can be achieved by including a forward-biased diode (D) in the circuit (Figure 3). The diode acts like a variable resistance, low when the charging current to the capacitor is high, then increases in value as the current decreases with time. This allows the series resistor used to be much smaller because it is only needed to prevent overload of the voltage source and damage to the diode if the capacitor is short-circuited. The diode used should be a small signal diode, such as a 1N914 or a 1N3595, but it must be housed in a light-tight enclosure to eliminate photoelectric and electrostatic interference. For dual-polarity tests, two diodes should be used back to back in parallel.

Test Hardware Considerations A variety of considerations go into the selection of the instrumentation used when measuring capacitor leakage: ■■ Although it is certainly possible to set up a system with a separate voltage source, an integrated one simplifies the configuration and programming process significantly, so look for an electrometer or picoammeter with a built-in variable voltage source. A continuously variable voltage source calculates voltage coefficients easily. For making high-resistance measurements on capacitors with high voltage ratings, consider a 1000 V source with built-in current limiting. For a given capacitor, a larger applied voltage within the voltage rating of the capacitor will produce a larger leakage current. Measuring a larger current with the same intrinsic noise floor produces a greater signal-tonoise ratio and, therefore, a more accurate reading. ■■ Temperature and humidity can have a significant effect on high-resistance measurements, so monitoring, regulating and recording these conditions can be critical to ensuring PRINTED CIRCUIT DESIGN & FAB / CIRCUITS ASSEMBLY


electrical test

Figure 4. Example capacitor leakage test system configuration.


measurement accuracy. Some electrometers monitor temperature and humidity simultaneously. This provides a record of conditions, and permits easier determination of temperature coefficients. Automatic time-stamping of readings provides a further record for time-resolved measurements. Incorporating switching hardware into the test setup allows automating the testing process. For small batch testing in a lab with a benchtop test setup, consider an electrometer that offers the convenience of a plug-in switching card. For testing larger batches of capacitors, look for an instrument that can integrate easily with a switching system capable of higher channel counts.

Configuration examples. Producing enough useful data for statistical analysis requires testing a large quantity of capacitors quickly. Obviously, performing these tests manually is impractical, so an automated test system is required. Figure 4 illustrates such a system, which employs an electrometer with builtin voltage source, as well as a switching mainframe that houses a low current scanner card and a Form C switching card. In this test setup, a single instrument provides both the voltage sourcing and low current measurement functions. A computer controls the instruments to perform the tests automatically. One set of switches is used to apply the test voltage to each capacitor in turn; a second set of switches connects each capacitor to the electrometer’s picoammeter input after a suitable soak period. After the capacitors have been tested, the voltage source should be set to zero, and then some time allowed so the capacitors can discharge before they are removed from the test fixture. Note that in Figure 4 the capacitors have a discharge path through the normally closed contacts of the relays. To prevent electric shock, test connections must be configured in such a way that the user cannot come in contact with the conductors, connections or DUT. Safe installation requires proper shielding, barriers and grounding to prevent contact with conductors. More complex test systems that combine leakage measurement with capacitance measurements, dielectric absorption and other tests, if desired, are possible. A simplified 30


Figure 5. Capacitance and IR measurement system.

schematic of such a test system using an LCZ bridge and a picoammeter with a voltage source is shown in Figure 5.

Test System Safety Many electrical test systems or instruments are capable of measuring or sourcing hazardous voltage and power levels. It is also possible, under single fault conditions (e.g., a programming error or an instrument failure), to output hazardous levels, even when the system indicates no hazard is present. These high-voltage and power levels make it essential to protect operators from any of these hazards at all times. It is the responsibility of the test system designers, integrators and installers to make sure operator and maintenance personnel protection is in place and effective. Protection methods include: ■■ Design test fixtures to prevent operator contact with any hazardous circuit. ■■ Make sure the device under test is fully enclosed to protect the operator from any flying debris. ■■ Double insulate all electrical connections that an operator could touch. Double insulation ensures the operator is still protected, even if one insulation layer fails. ■■ Use high-reliability, fail-safe interlock switches to disconnect power sources when a test fixture cover is opened. ■■ Where possible, use automated handlers so operators do not require access to the inside of the test fixture. ■■ Provide proper training to all users of the system so they understand all potential hazards and know how to protect themselves from injury. CA

Dale Cigoy is lead applications engineer at Keithley Instruments (; august 2010


Under-Component Cleaning:

How Low Can You Go? Why visual indicators as a cleanliness gauge may be dangerous practice. by Harald Wack, Ph.D., Umut Tosun, Joachim Becht, Ph.D., Helmut Schweigart, Ph.D., and Chrys Shea Preventing field failures due to electrochemical migration used to be relatively easy: Use a water-soluble flux and clean the board after soldering. This solution no longer holds true, and sometimes causes more problems than it prevents. Water-clean fluxes, also known as organic acid (OA) fluxes, are often preferred over no-clean products for highreliability applications because of their higher activity. They are more effective at removing oxides, promoting wetting and overcoming solderability variations. Problems arise when their residues are not fully cleaned from the assembly. OA fluxes are active at room temperature, and all they need to begin damaging the assembly is DC voltage and atmospheric moisture. When OA flux residues remain on a circuit assembly, the concern is not a matter of if the circuit board will fail; it is a matter of when it will fail. Fully cleaning the harmful residues gets increasingly difficult as components get smaller and standoff heights shrink (Figure 1). Many low-standoff components are designed only for no-clean soldering processes; however, OEMs and assemblers sometimes have no choice but to use them in water-clean applications. And without a definitive, nondestructive test for cleanliness, both parties harbor concerns about the long-term reliability of the end-product. To characterize the cleanability of modern OA solder pastes, a simple experiment was devised. PWBs were assembled with 12 of the industry’s most popular pastes, reflowed in an air atmosphere, cleaned, and visually graded for residues. Areas easily reached by the wash process, like gullwing or J-lead components, were represented by unpopulated component pads printed with solder paste. Areas obscured by low-standoff components like µBGAs or QFNs were conservatively represented by 0603 components (Figure 2). Reflow was performed in an ERSA Hotflow 3/20, 10-zone reflow oven using typical thermal profiles for SnPb and Pb-free (SAC 305) alloys, and cleaning was performed in a Speedline Aquastorm AS200 inline cleaner at a belt speed of 2 ft./min. Water temperatures of 120°, 140° and 150°F were used. Three boards were processed at each setting; the three scores were averaged and reported. AUGUST 2010

The gold standard for assessing cleanliness is ion chromatography (IC), but performing IC analysis on a large sample size is time-consuming and cumbersome. To rapidly assess flux residue cleanability, a visual cleanliness scale (Table 1) was developed. It should be noted that visual cleanliness does not necessarily indicate ionic cleanliness, but


Figure 1. Under-component clearances for common SMT components (shown to scale).

Figure 2. 0603 components on test vehicle. 31

AcAe Accurate Circuit Engineering American Standard Circuits Altium Inc. AT&S Americas Bare Board Group Big C-Dino-Lite Scopes CAD Design Services Cadence Design Systems, Inc. CMR Summit Custom Analytical Services DownStream Technologies Elite Sales International EMA Design Automation Fidus Systems, Inc. Flex Interconnect Technology Intercept Technology IPC Designers Council K&F Electronics LPKF Laser & Electronics Mentor Graphics National Instruments North Bay Technical Oak-Mitsui Technologies Overfly Pacific Corporation P.D. Circuits, Inc. Polar Instruments Inc. Polliwog Corporation Rogers Corp. SEP Co. Ltd. SFM Technology, Inc Sierra Circuits Inc. Sigrity Inc. Taconic Tsuding Global (USA) T-Tech Inc. TTM Technologies Whizz Systems Inc. Zero Defects Int'l, LLC Zuken

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*'& $"  ("#"*' ##% F1: How to Plan Your Design to Save Time and Reduce Layer Counts F2: Test Strategies for the Designer and Fabricator F3: Counterfeit Electronic Components F4: Designersâ&#x20AC;&#x2122; Roundtable F5: Thermal Management in Advanced PCBs F6: What PCB Designers Must Know about Post-Assembly Cleaning F7: Maximizing Electronic Design Productivity on Your Desktop F8: The Latest in HDI Manufacturing Techniques 19: Circuit Grounding to Control Noise and EMI 20: Placement and Routing of Complex PCBs

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SMT CLEANING Table 1. Visual Cleanliness Scale Score





Some minute specs or lines


Potential PASS


Contamination in a few areas


Contamination in most areas



Contamination in all areas untouched



Improving Cleanliness The next phase of the experiment added a cleaning solution to the wash. Cleaning agents work in two main ways: They lower the surface tension of the water so it can reach into tight areas, and they help act on the residues to dissolve them. At wash temperatures of 140°F, introduction of a cleaning agent at a 5% concentration dramatically improved under-component cleaning. At 150°F, only a 3% concentration was required to produce similar results

Components 5.0


The first test assessed the overall process friendliness of the solder pastes by evaluating their cleanability on unobstructed pads using only deionized water. Results (Figure 3) are ranked in order of their cleanability. Of the 12 pastes tested: ■■ Five demonstrated easy cleanability. ■■ Two posted scores in the 4+ range, indicating potentially good cleanability. ■■ Five pastes failed. ■■ Two of the failures showed exceptionally poor cleanability. The next test mechanically removed the 0603s and examined the postcleaning residue underneath. Figure 4 presents them in the same order as in Figure 3. Under-component cleaning results differ substantially from the bare board results: ■■ Paste A, which demonstrated bestin-class cleanability in visible areas, actually showed the worst results in obstructed areas. ■■ All the pastes left some degree of residue. ■■ Three pastes scored 4s at some, but not all, temperatures. The average cleanliness scores of visible and obstructed areas were then compared (Figure 5). The comparison produced eye-opening results: ■■ Only one of the five pastes that demonstrated excellent cleanability in the open areas showed good cleanability

under the components. The other four received failing grades. ■■ The two pastes that showed potential for good cleanability on the bare board areas showed similarly good cleanability in the obstructed areas (pastes H and I). ■■ The three pastes that produced obviously unacceptable results in the visible areas produced similarly unacceptable results in non-visible areas. ■■ Half the pastes tested showed substantial drops (more than one grade point) in cleanability when the different areas are compared. The cleaniness differences between the two areas are obvious – what you see is not necessarily what you get. Relying on visual indicators to gauge an assembly’s cleanliness may be dangerous practice, depending on the sol-




4.0 3.0 2.0 1.0 0.0 A*













Figure 3. Solder paste residue cleanability in open areas of circuit assembly.

Components 5.0


Test Results

der paste formulation and processes to which it has been exposed. The ionograph test that is commonly used to monitor cleaning processes’ effectiveness can also lull users into a false sense of security. In many cases, the alcohol-water mixture in the test solution does not completely dissolve baked-on residues under the low-standoff components, and the test fails to detect the actual contamination levels. Even if it does fully dissolve the residues and detect all the contamination, the test averages it across the entire surface area of the assembly, diluting the localized dangerous level to a perceived overall “safe” level.



visible residues generally do indicate residual ionic contamination. Therefore, the only grade on this scale that could be considered a “pass” is a 5. Several areas assigned a score of 5 were confirmed clean with ion chromatography. Scores of 4 or more indicate that the reflow and/or cleaning process could likely be dialed in to produce acceptable results. Scores of 3, 2 or 1 are unacceptable process failures.





4.0 3.0 2.0 1.0 0.0 A*













Figure 4. Solder paste cleanability under low-standoff components. AUGUST 2010


(Figure 6). Introduction of cleaning chemistry, even at low concentrations, made a substantial impact on the cleanliness of the areas obscured by the low clearance components: ■■ In 12 of 24 cases, the introduction of a cleaning agent produced a perfect score of 5. When cleaning agents were not used, no perfect scores were recorded over the course of 72 trials. ■■ In all cases except one, the addition of chemistry improved cleanliness under the component. ■■ Pastes L and F, which demonstrated some of the poorest cleanability with DI water alone, scored 5 and 4+ when cleaning agents were added to their wash process. For many years, OA solder pastes were referred to as “water-soluble.” Recently, that term has migrated to

“water-washable” or “water-cleanable,” indicating that modern formulations do not exhibit the easy solubility of their predecessors. The current data support this migration of terminology, demonstrating that residues under components can be satisfactorily washed away – but not with water alone. Consider trying to wash a car, household laundry or dirty dishes with water only. The car, clothes or dishes would be extremely difficult to clean without the assistance of detergents. Industrial cleaning processes are no different from domestic ones; they all work better when they incorporate cleaning agents. In the case of circuit assemblies and modern solder pastes, cleaning chemistries are rapidly becoming a necessity. For low-standoff components like microBGAs and QFNs, engineered cleaning solutions

are assuring ionic cleanliness and alleviating the concerns of electrochemically induced field failures for everyone in the supply chain. CA

Harald Wack, Ph.D., Umut Tosun, Joachim Becht, Ph.D., and Helmut Schweigart, Ph.D. are with Zestron (; Chrys Shea is founder of Shea Engineering Services (

Figure 5. Comparison of the average cleanability of visible and obstructed areas.

Figure 6. Effect of cleaning agent on under-component cleanliness. AUGUST 2010




Staying Cool and Dry in the Midst of Summer When printing quality goes awry, check the climate. Your forehead feels a little moist. Palms are sweaty. Heat begins to rise out of your collar, and breathing becomes a chore. Mind you, you haven’t run a marathon; all you’re doing is moving a few boards and spatulas. Chances are if you’re feeling the heat, so is your printer. My general rule is this: If I feel OK, then the process is probably OK. Too hot, we both sweat; too cold, we both quake. We often understandably can get so focused on the advanced options and capabilities of our printers, the impact of the print environment on the process gets overlooked. Assemblers need to be aware that the environment in which they print has a significant influence on the results, as temperature and humidity can significantly change the viscosity of the material – in most cases, solder paste – being printed. Generally, the optimum temperature range inside the printer should be 70° to 77°F (21° to 25°C). If the temperature is too high, material will start to lose viscosity, which can lead to bridging and smearing. If the air conditioning system happens to be very good and the temperature is too low, material viscosity increases, and the result may be insufficients from blocked apertures.

constant temperature to within +/-1°. One note of caution: Select a system that filters and monitors airflow. Solder pastes contain high volatile solvents, and excessive airflow will dry out the print materials, which can lead to other issues. It is critical that the heat is moved out of the printer and cooled through a diffusing system that doesn’t dry out the print material. ■■ Relocate the printer/change the ambient temperature in the factory. Seems an obvious solution, but you’d be surprised at how often this isn’t considered. Before joining DEK, I worked at a manufacturer where we did just this; we moved the SMT line away from the external windows to aid with temperature management. I’ve also seen situations where, even when the factory is properly cooled, the line might be next to the “Goods Out” door. Not surprisingly, in the heat of summer/freeze of winter, when the door is constantly opened and closed, outside temperatures impact the print and paste performance. Consider the factory layout and line locations very carefully. And, of course, adjusting the temperature control within the factory is an option. ■■Change print materials. Solder paste materials development has come a long way in the past 10 Printer temperatures outside the 70° to 77°F range years. With today’s expertise and manipulation of the paste DNA, can affect paste viscosity. modern materials are formulated to be somewhat resistant to heat and humidity. I’ve seen a material change work wonders on a process. In fact, If printing quality is fine for a few hours, then all many years ago, I was working with a customer of a sudden, problems like bridging or smearing arise, that was having bridging problems. The factory and if there haven’t been changes to the paste, stencil was very hot, and the company didn’t have the or other inputs, the environment could be the culprit. funds to invest in a new HVAC system. After our Troubleshooting the issue is as simple as turning on evaluation, we suggested they consider changing the SPC system to monitor the temperatures inside materials, which they did, and which dramatically the printer. It may reveal a cycle in which printing is improved the results. fine in the morning hours when the system is mainClive Ashmore These are easy remedies for a frequently misditaining a steady 71°/72°F, but when the afternoon is global applied agnosed problem. Just as the environment impacts rolls around and the temperature peaks at 79°/80°F, process engineering your own well-being, it can do the same for the that’s when defects begin to appear. Using the SPC manager at DEK print process. Remember the simple rule: If you’re tools, it is fairly simple to determine if there is a corInternational (dek. not comfortable, odds are neither is your printer. relation between defect rates and the environment, com); cashmore@ His column Be cool. CA and in most cases, it is easily resolved. appears bimonthly. For environmentally induced print process issues, there are several fixes to consider: ■■ Install a temperature control monitor. Most screen-printing equipment manufacturers offer an automatic temperature control system that will either chill or heat, depending on what’s required. These systems keep the inside of the printer at a



august 2010



Don’t Drown the Part! Excess flux can disturb PoP placement. This month we feature one recent process control

only be on the surface of the balls. In this case, however, the part has been drowned, with flux covering all the balls and the package surface. Excess flux can result in component float during reflow, and depending on the solvent in the flux, the part could even jump off the board during reflow. Excess flux should be avoided; it shows poor control, may cause problems during cleaning and will affect underfill application (if conducted). Flux or dip paste is used to assemble PoP components during a typical SMT process. As a guide, the package balls would be dipped to a depth of 50% of the height of the balls. In this example, the flux Grow With the tray clearly was not flat; 3D Measurement Leader the amount of the flux was uneven on the tray, Koh Young or the doctor or control blade height was incorrectly set. These are typical defects shown in the National Physical Laboratory’s interactive assembly and soldering defects database. The database (, available to all this publication’s readers, allows engineers to search and view countless defects and solutions, or to submit defects online. CA

issue submitted to the database. Figure 1 shows the bottom of a package-on-package (PoP) device, a small BGA, prior to placement on the top of the bottom package. The liquid flux should

Koh Young Technology has set a new standard in 3D measurement and analysis tools for ultimate process optimization and higher yields. Koh Young’s patented true 3D inspection technology out-performs all others. Partner with a company that thinks and works in real time to help you meet your challenges and goals. Koh Young is a global company with local support, your partner in building


Dr. Davide Di Maio is with the National Physical Laboratory Industry

better profitability through

and Innovation

improved quality.

division (; defectsdatabase@ His column appears monthly.

Europe • USA Korea • Singapore China • Japan

august 2010

Figure 1. Excess flux on the balls and package surface will cause problems during assembly and cleaning. PRINTED CIRCUIT DESIGN & FAB / CIRCUITS ASSEMBLY



5 Issues Driving the Cost of Poor Quality Why common metrics fail to root out the causes, and actually add cost in the process. Many companies adopt a reactive approach to

Tony Bellito is quality/product engineering manager at Epic Technologies ( He can be reached at tony.bellito@epictech. com.


measuring the cost of (poor) quality that focuses on defects and nonconformities. Most companies measure scrap, rework and customer returns, and often “fix” the problem through increased inspection or process adjustments. However, those fixes often fail to eliminate the root cause of the problem. We try to take a more proactive approach by educating customers on ways to reduce the cost of poor quality through upfront planning. This month, we look at the top five areas where a proactive approach saves money and capitalizes on the efficiencies inherent in a Lean manufacturing philosophy. 1. Failure to adopt DfM recommendations. Lean manufacturing is most efficient when consistent processes are in place. Comprehensive DfM guidelines are part of ensuring repeatable, consistent processes. Optimizing designs for Lean manufacturing requires designers to balance goals for functionality, material cost and long-term product enhancement flexibility against throughput cost and logistics efficiency. Poor pad geometry and component layout location contribute most to poor quality. In addition to increasing the potential defects, poorly designed PCBs add processing cost. For example, improperly sized through-hole pads and holes will result in unacceptable solder joints, which drive added inspection and touchup. Lack of fiducials, improperly placed fiducials, or fiducials in the wrong shape or size affect the accuracy of SMT component placement. Incorrect orientation of bottom-side SMT components can increase the frequency of opens and shorts, resulting in a reduction of quality and increased inspection and touchup. Incorrect SMT land patterns can cause opens, shorts, tombstoning, etc., resulting in a reduction in quality and added inspection. 2. Design that drives manual processing. Hand insertion vs. automatic placement triples the labor cost. Hand soldering vs. wave or reflow soldering results in triple the cost of automated soldering multiplied by the number of leads being hand soldered. 3. Component selection. Component sourcing decisions can impact quality, process efficiency, schedule flexibility and product delivery. Consider materials compatibility, thermal characteristics and the component’s ability to anticipate heat cycles, availability and supplier quality track record. Sole sourcing components adds additional complexity and potential cost, since it limits options in the event of quality or availability issues. When a Lean manufacturing process is involved, another consideration is whether the component supplier will support Lean supply chain principles.


4. Design for test and testability. Lean test strategies often use standardized test platforms. Efficient in-circuit test requires a PCB designed to industry standards and with good access points. And, a robust test process can detect both workmanship and nonprocess-related defects. According to an Agilent study, analysis of manufacturing defect root causes suggests 10-15% of defects are actually attributable to nonfunctioning parts or defective materials, rather than being assembly process related. EPIC has seen similar statistics in its internal defects analysis. Test point access also can be a significant cost driver. If a design doesn’t have test point access sufficient to permit automated ICT, AOI or x-ray inspection or flying probe test are higher-cost alternatives. Those tools have longer test times, are less effective in testing the product, and require greater operator interface time. Custom functional test systems alone may not provide as robust a test process and typically increase test time and overall test cost. Functional test is another area. In many cases, customers consign less-than-optimal functional testers. Inefficiencies inherent in a poorly designed functional tester are only part of the potential cost driver. Maintaining multiple unique customer-supplied testers carries a cost. When possible, use a standardized proprietary functional test platform. When customers insist on using a poorly designed functional tester, provide a report on risks and added cost. Stress and strain are also potential areas of concern. Design an assembly process that minimizes the potential for overstressing PCBs and a robust testing process to catch issues that may arise in this area. 5. Test correlation. With typical product cost models, it is not realistic to say that zero defects are consistently attainable. Achieving near “zero” levels attainable in a robust process requires detailed upfront planning to ensure all variables and controls are welldefined, implemented and monitored. Test correlation between a contractor and its customers’ testing can be a challenge. The amount of non-value-added activities surrounding differences in test coverage from contractor to customer is huge when this issue is not addressed proactively. Although full test correlation is not always attainable because customers may be running tests they choose not to outsource, based on time considerations such as burn-in, all other elements of test correlation should be considered. The key to driving down cost and eliminating costs of poor quality is all based on one thing: the contractor’s and customer’s willingness to truly work together and plan for success.  The more robust the front-end planning, the more robust the process and overall product quality. CA august 2010


Printer-Caused Bridging Identify and solve printer-related solder defects. As noted last month, bridging

is solder connecting or, in most cases, misconnecting two or more adjacent pads that come into contact to form a conductive path. This month, we look at instances caused by the screen printer, and how to mitigate them. Problem: Poor gasketing (paste oozes beneath stencil during printing, increasing chance of wet solder paste bridges). Recommendations: ■■ Zero print gap between stencil and PCB.

■■ ■■

Check paste smear underneath stencil. Check sufficient stencil tension.

Problem: Misaligned print will challenge the paste to pull back to pads during molten stage, increasing the potential for bridging. Recommendation: Ensure print accuracy and consistency for both print strokes. Problem: Smearing and bridging phenomenon on the next printed board after stencil cleaning operation.

Figure 1. Misaligned or wet stencils are among the causes of bridging.

Recommendations: Verify stencil is dry after cleaning and before next print. ■■ Standard cleaning mode is wet/ vacuum/dry.


Problem: Poor print definition with dog ears, especially on finepitch components. Recommendations: ■■ Check board support. ■■ Adjust separation speed to achieve minimum dog ears. (Different paste chemistry requires different separation speed to minimize dog ears.)

Paul Lotosky is global director – customer technical support at Cookson Electronics (cooksonelectronics. com); His column appears monthly.

Problem: Dented squeegee blades could result in uneven print pressure. Recommendation: ■■ Check squeegee blade condition. CA

Fast and Accurate PCB Depaneling SAyAkA PCB RouTeRS When time and accuracy are vital, Seika’s Sayaka PCB routers are the only solution for low-stress depanelization. Features: • Low-stress, fast and precise depaneling • Simple Graphical software programming capability • Clean depanelization through efficient dust collection • Standard QR code reader and fiducial check by CCD camera • Low maintenance and low running cost • Small footprint • Max board size 500mm x 600mm (20”x 24”) • Tabletop, standalone and inline routers available

Learn more about Seika’s entire SMT line of assembly products at Atlanta Office: 3030 Business Park Drive, #3030-B Norcross, GA 30071 Phone: (770) 446-3116 Fax: (770) 446-3118 august 2010

Los Angeles Office: 3528 Torrance Blvd., Suite 100 Torrance, CA 90503 Phone: (310) 540-7310 Fax: (310) 540-7930




The Pb-Free Control Plan

Proper documentation can identify risk associated with particular COTS parts.

A commercial systems manufacturer working on a major defense program experienced failed parts during reliability testing. It was attempting to incorporate commercial off-the-shelf (COTS) computer-related hardware into a battlefield system and was experiencing reliability issues. The parts were labeled by the vendor as “compliant to military (or MIL) standards,” but not clearly identified as SnPb or Pb-free. Immediate support was provided in the form of an analysis of COTS components using x-ray fluorescence (XRF) and scanning electron microscopy (SEM) with

Figure 1. A sample prohibited material flow chart, which can be used to track implementation of COTS parts in adherence with a Pb-free control plan.

ACI Technologies Inc. (aciusa. org) is the National Center of Excellence in Electronics Manufacturing, specializing in manufacturing services, IPC standards and manufacturing training, failure analysis and other analytical services. This column appears monthly. 40

energy dispersive x-ray spectroscopy (EDS) techniques for chemical identification of Pb-containing parts. The Pb-free components were clearly identified and assessed on the associated failure risk based on its intended application environment. This risk analysis permitted a cost trade-off consideration to determine whether to refinish the parts with SnPb or with a modified process for mixed lead and Pb-free components. This minimized program delay and resulted in improved reliability testing performance. The recommended longer-term solution was a more proactive approach in development of a Pb-free control plan both internally and through their vendors, so that risk associated with particular COTS components is more clearly identified in the future. A prohibited material flow chart was created (Figure 1) to ensure proper implementation of components throughout the process – from receiving to final assembly. It was recommended that a Pb-free control plan be developed in advance of the upcoming Department of Defense requirement in accordance to guidelines provided by the AIA and the Pb-free Electronics Risk Management consortium (per GEIA-STD-0005-1 and GEIA-HB-0005-1). It is important to note that many COTS parts sup-


posed to be compliant to SnPb manufacturing applications may in fact result in a high failure risk. The best way to prevent unanticipated risk is through thorough parts identification and tracking, internally and externally, throughout the supply chain. Also, ensure that each vendor is aware that implementation of the Pb-Free Control Plan will soon be a requirement for parts associated with DoD programs in order to simultaneously support supply chain transition and improve program reliability. CA

SEARCHING FOR EMS PROVIDERS? The CIRCUITS ASSEMBLY Directory of EMS Companies lists more than 1,850 EMS facility listings worldwide, including detailed info on: • Facility address, phone, fax, URL and contact person • Annual sales revenue • Number of employees • Number and type of assembly lines • Size of manufacturing floor • Services offered • Certifications

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august 2010






Capacitor Design Setup Flow

Cable Connector 3800 series has locking system to ensure retention force after connector is mated. Has sequential mating, a durable potting shield design, and achieves weight and size reductions. Rated at 20,000 mating cycles. Weighs 34% less than the original design and contains 18 contacts. Is 22.3 mm wide x 8.5 mm deep, with a board-mounted profile of 5 mm and a weight of 1.39 g.

OptimizePI v. 2.1 analysis-based flow is said to fully automate design setup and electrical analysis tasks associated with pre-layout decoupling capacitors for power delivery networks in PCBs and IC packages. Optimizes initial decoupling capacitor designs that are near-final in nature. Reportedly reduces subsequent design iterations and provides high-quality power delivery networks to help mitigate SSO and other issues. Describes stack-up attributes, plane size and shape, decoupling capacitor placement guidelines and a library of candidate decoupling capacitors.

Field Solver Enhancer XFE (Crosshatch Flex Enhancement) technique couples novel 2-D field solvers with a unique algorithm to correct for the effects of flex over a range of typical controlled impedance structures. Enables solvers to more closely model the effects of a wide variety of crosshatch geometries. Permits configuration of hatch pitch (HP) and width (HW). Reduces prototype turns when producing impedance controlled flex PCBs. Is said to be for any PCB type deploying meshed/cross-hatched return planes (e.g., interposers).

Hirose Electric


Polar Instruments


Fine-Line Photoresist

Benchtop Vibration Isolation System

PLCC plugs are categorically molded and machined, and designed to connect PCBs and PLCC production sockets. Attached to cable with numerical coding for easy identification of the plug-to-pin connection. Reportedly permit reliable socketing and SMT insertion. Series includes PLCC-20 plug, PLCC-28 plug, PLCC-32 plug, PLCC-44 plug, PLCC-52 plug, PLCC-68 plug.

Riston PlateMaster PM300 dry-film photoresist is a fine line CuSn and copper/solder plating film. Is said to have excellent resolution and wide processing latitude.

ELpF can be repositioned, even with a load and in float. Does not damage vibration isolators. For sensitive devices. Features load capacity of 100 or 300 lbs. Has a 3" high nominal profile; uses a 16" x 19" standard tabletop, and weighs 40 lbs. For supporting atomic force microscopes, microhardness testers, analytical balances, and other gear in laboratories and Class 100 cleanrooms.


DuPont Electronics and Communications

Kinetic Systems

Power Integrity Co-Simulator

LED Thermal Management

Enhanced CAM Tool

Sphinx for Signoff for IC packaging and PCB design uses M-FDM methodology. Analyzes complex designs prior to release to production and final signoff for manufacturing. Features include support for DXF, MCM, BRD and SiP file formats; performs quick “what-if analysis” by permitting modification to existing designs; adds capacitor vendors’ libraries, and more.

SinkPAD technology for aluminum IMS PCBs conducts heat by enabling a direct thermal path between the LED and surrounding atmosphere; eliminates thermal resistance introduced by dielectric material in a traditional IMS PCB or MCPCB. Reportedly removes the substance with the lowest thermal conductivity/highest thermal resistance from the structure. Isolates dielectric’s metal base electrically and leaves it thermally connected.

InCAM 2.0 features a third-generation etch compensation algorithm said to run up to five times faster than previous versions, a revised, easy-to-use user interface, automatic impedance line recognition, automatic backdrill creation and analysis, and critical via checks. Improves to signal layer, silk screen and solder mask repair, via optimization and many more DfMs, analysis and editing functions. Enables co-tooling of jobs without user conflicts.

E-System Design


Frontline PCB Solutions

august 2010






Laser Micrometer

BGA/QFP Lead Inspection

IG series micrometer technology is for edge guiding of opaque, transparent or translucent materials, position control, outer diameter measurement, and gap control. Control system includes numerous built-in, application-specific operation modes, enabling most installations to be configured and operational within seconds. Has a small footprint. Alignment and setup are simplified with highly visible beam and LED bar monitor position display.

PR1 BGA Solder Ball Checker is for handheld inspection of BGA soldering and QFP lead sections. Provides inspection of soldered points and BGA surfaces; features a conductive body for ESD. Enables visual inspection of QFP leads and chip parts. Is 50 x 30 x 15 mm, 25 g. Comes with a wrist strap. Is capable of inspecting the interior section of BGA packages using white LED lighting system. With an expanded lens, it is capable of up to 7X magnification.



01005 Tape-Capable Feeder 4-mm ITF3feeder is for A-Series pick-and-place machines. Reportedly improves reliability of 01005 component placement. Accepts W4P1 all-plastic tape standardized by the IEC; tape eliminates paper dust that can cause bad solder connections to the microminiature components. Is static-free. Helps cut waste by 75% compared with traditional 8-mm tapes on a 2-mm pitch.


Seika Machinery




Ag-filled Conductive Adhesive

Replacement Nozzles

Machine Vision Software

Hysol Eccobond CA3556HF is said to cure quickly at low temperature. Suitable for crystalline-silicon and thin-film manufacturing. Bonds Ag- and SnPbAg-coated tabs and c-Si cells. Stress minimization properties compensate for CTE mismatches. No-mix, one-part formula. Applications include membrane switches, displays on temperature-sensitive substrates, automotive sensor and RFID tag assembly.

Mydata Midas replacement nozzles reportedly are direct replacements for OEM nozzles. Are said to be compatible with TP9-1, TP9-2, TP9-3, TP9-4, TP11, TP12, TP18, MY9, MY12, MY15, MY19, and MY100 (SX/DX).Tool range includes the following nozzle types for finepitch components: C14, A12, A13, A14S, B12, A23, A24, and C23. Special Midas nozzles include spring suspended tools (A23S, A24S, C23S), MELF tools (A34, B34, B24, B23, C24), flat pipe tools (blade), multi-port tools, ESD ceramic tools, micro-thin tools and gripper tools. Cover QFPs to BGAs to 01005s.

Visionscape 4.1 is scalable software for machine vision boards, GigE solutions, and smart cameras. Includes blob analysis, OCR, OCV, barcode, vector and edge algorithms, plus pattern-matching tool Intellifind. Additional tools include color matching and color segmentation. Color matching can be used in high-speed applications such as sorting parts, and color segmentation enables other tools to be applied in a specific color plane. Can directly be transferred from smart camera platform to a PC-based solution without reprogramming.


Count On Tools


High Mix Selective Soldering

High-Speed Valve Actuator

PCB Prototyping System

SelectiveLine (formerly the GoSelective light inline) permits upgrade of a fluxer and preheat modules. For high mix. Features precise axis system for exact positioning of various workstations, and is capable of handling bare boards or assemblies in carriers up to 500 x 500 mm. Pb-free capable. Comes with fiducial recognition for automatic PCB alignment, process visualization, and offline teach program. Drop jet fluxer control monitors fluxer nozzle function and measures flux quantity of each drop.

Backpack Valve Actuator can produce smaller fluid deposits required in assembly of advanced products, such as medical devices and portable electronics. Incorporates advanced miniature solenoid technology; mounts the solenoid used to open and close the valve directly on the valveâ&#x20AC;&#x2122;s air cylinder. Achieves valve actuation speeds of 5 - 6 msec. and cycle rates of 800 per min.

Quick Circuit QCJ5 is equipped with Z-axis motion control; 12, 24, or 32-position automatic tool change; automatic tool-depth control; four-zone precision vacuum table; resolution of 0.00025"; 60,000 or 100,000 RPM variable speed spindle; 0.004" trace and insulation width; pre-contact pressure foot, and integrated front-panel control of common system commands.

Seho Systems

Nordson EFD

T-Tech Inc.


august 2010






Selective Soldering Programming Tools High-Brightness Digital Microscope VHX-1000 features real-time, 16-bit imaging resolution. Brightness range has been increased from 256 levels to 65,536 levels. 3CCD color clarity has increased from 16 million to over 2.8 trillion colors. Has doubleâ&#x20AC;&#x2122;r automatic lens/zoom recognition system; recognizes, in real time, which lens is mounted to the camera, as well as the current magnification.

Defluxing Software Trident eSPC software comes on all PCequipped Trident defluxing systems. Permits scanning (or manually entering) individual assembly barcodes as they are loaded. Stores and shows all process parameters and process data. Automatically captures assembly serial number; date/time of batch (start and completion); and programmed and actual temperature for wash solution, drying time, drying temperature and more.

KISS-Ware 2.0 software and programming tools import PCB assembly data from a variety of sources. Inputs (Gerber, DXF, digital or scanned board images) to generate PCB dimensions and display X/Y data points that will become the fluxing and soldering targets. Enables program editing on the PCB image. Automatically generates machine commands required for processing the job. GUI highlights path identifying everything that has been programmed. Typical programming time reportedly 5 min.


Aqueous Technologies

ACE Production Technologies

august 2010







Manual Soldering IR Preheaters

Die/SMT Parts Placement Siplace CA combines die placement from wafers with classic SMT placement technology. Reportedly eliminates special die bonding processes. Features flip unit, special vision systems, and linear flux dip unit. Each Speedstar CP 20 head is able to place up to 9,000 flip-chips or 6,000 dieattach cph in sizes ranging from 0.8 to 18.7 mm with an accuracy of ±10 µm. Handles different wafers, which are replaced automatically.


Radial Coat Valve RC200 sprays low-viscosity fluids onto the inside walls of a cylinder to create a layer of coating. Integrates front closing valve technology, to start and stop fluid flow, with an air motor to spin the coating nozzle. Nozzle rotation uses centrifugal force to propel the fluid directly onto cylinder walls in a 360° pattern. Fluids include water, solvents and low-viscosity lubricants.

Updated IR preheaters are for manual soldering and desoldering of SMT, through-hole and other thermal applications. Total heated area is segmented into four selectable zones. Complement underpowered rework systems lacking effective bottom heating. Feature easy-to-adjust flexible board fixtures. Spring-loaded board clips permit thermal expansion without bending boards. PCB tooling options include four-sided and bottom board support, and extended reach board clips.


Precision Valve & Automation

VJ Technologies



LED-Based Machine Lighting

Thermally Conductive Adhesive

Flip-Chip Placement

Nerlite machine vision lighting now includes approximately 300 standard lighting configurations in multiple geometries, sizes, and wavelengths. Includes IR, UV, blue, and white wavelengths to most standard geometries. Basic light geometries include ring, area arrays, bar, dome, dark field, and high-intensity. Configurations include edge-to-edge backlights, and DOAL, CDI and SCDI illuminators. 100% LED-based.

MT-815 low modulus, high thermal conductivity adhesive can be used for large die, in die attach applications, or as a solder replacement. Has a modulus of <1 GPa; is reportedly less likely to crack or delaminate under the stresses of temperature cycles. Formulated to achieve thermal conductivity of >10 W/m-K.

GenesisSC is tailored for dies and passives placement, including 300 mm wafers. Placement accuracy is said to be ±10 µm @ Cp>1. On-board linear thin film applicator provides dipping capabilities for paste or flux.


Lord Corp.

Universal Instruments Corp.

Wizard-Driven AOI Software

Mixer Cartridges

LED Nozzles

AOI software v.5 now includes 64-bit computing technology, standard 12 Gb of memory (expandable to 72 Gb), and integrated 3D Gerber translation; reportedly can generate production ready 3D inspection program from stencil data within 5 min. Specifies stencil thicknesses and step stencil data. Inspection parameters are set automatically based on user input. GenCad and GenCam handling permit mapping individual components and lead numbers to Gerber data.

B Series 50 mL cartridges have interfaces for mixer and pre-assembled built-in piston retention. Have rectangular backs and are available in 50mL, fully assembled, 1:1 and 2:1 ratio polypropylene cartridges. Offer a removable cap, a stronger attachment flange, separated outlets, and preassembled pistons with or without o-ring. Cartridges with 4:1 and 10:1 ratios will be available soon.

Custom SMT pick-and-place nozzles for Cree LED components offer special handling operations to prevent damage to the optical lens. Reportedly avoid mechanical stress on the LED lens by not touching the optical surface during component picking or placement processes. Permit better placements with odd-form components. Can be applied to any style of pick-andplace nozzle for any OEM or machine type.

Machine Vision Products

Sulzer Mixpac USA

Count On Tools


august 2010


Professional CAM Software without the Professional Price! Precious Metal Finishing for Commercial, and High Reliability Printed Circuit Needs.

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august 2010






august 2010

Special Advertising Section

Special Advertising Section

Assembly Insider

Assembly Insider

Ad Index To learn about the advertisers in this issue, go to or and select “Current Issue” to access the digital edition. This will provide you with direct links to the websites of each advertiser in this index. Company

Page No.

Bare Board Group, . . . . . . . . . . . . . . . . . . . . 45 Bare Board Group, . . . . . . . . . . . . . . . . . . . . 47 Design 2 Part, . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Digi-Key Corp., . . . . . . . . . . . . . . . . . . . . . Cover 2 DownStream Technologies, . . . . . . . 3 DownStream Technologies, . . . . . . . . . 5 DownStream Technologies, . . . . Cover 3 eFABPCB, . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Electronics Midwest, . 15 EMS Directory, . . . . . . . . . . 40, 47 EzPCB, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Fine Circuits, . . . . . . . . . . . . . . . . . . . . . . . 46 Imagineering, . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Imagineering, . . . . . . . . . . . . . . . . . . . . . . . . . . 46 Koh Young Technology, Inc., . . . . . . . . . . . . . 37 MIRTEC, . . . . . . . . . . . . . . . . . . . . . . . . Cover 4 National Instruments, . . . . . . . . . . . . . . . . . 4


The CIRCUITS ASSEMBLY Directory of EMS Companies

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lists more than 1,900 EMS facility listings worldwide, including detailed info on: • Facility contact info • Annual sales revenue • Number of employees • Number and type of assembly lines • Size of manufacturing floor • Services offered • Certifications

circuits assembly. com/dems

Numerical Innovations, . . . . . . . 45 Online Electronics, . . . . . . . . . . . . . . . . . . . . . 46 Overnite Protos, . . . . . . . . . . . . . . . . . . . . . . . 46 PCB FAB Express, . . . . . . . . . . . . . . . . . 45 PCB UPdate, . . . . . . . . . . . . . . . . . . . . . . . . 47 PCB West, . . . . . . . . . . . . . . . .insert, 32, 46, 47 Powell-Mucha Consulting, . . 43 Seika Machinery, . . . . . . . . . . . . . . . . . . . . 9, 39 Service Excellence Awards, . 21 Sierra Circuits, . . . . . . insert, 17 Sierra Circuits, . . . . . . . . insert, 17 SMTA International, . . . . . . . . . . . . . . . . . . . 13 Superior Processing, . . . . . . . . . . . 45 Wise, . . . . . . . . . . . . . . . . . . . . . . . . 19 The advertising index is published as an additional service. The publisher does not assume any liability for errors or omissions.

Advertising Sales North America/Europe/Asia (except Korea):

UP Media Group, Inc. PO Box 470, Canton, GA 30169

Circuits Assembly Sales Manager:

Krista Fabian, 302-519-4064,

Printed Circuit Design & Fab Sales Manager:

Frances Stewart, 678-817-1286,

Korea Sales: Young Media, 82 2 756 4819,




In Case You Missed It Embedded Components “Industrial PCB Development Using Embedded Passive and Active Discrete Chips Focused on Process and DfR” Author: Arnaud Grivon; Abstract: This paper discusses aspects of the PCB embedding technology developed in the frame of the HERMES project, a Europe-funded research program to establish an industrial platform capable of producing PCBs with two layers of embedded components, including large die sizes. The focus is on the main embedding process steps and prerequisites such as chip thinning and plating. DfR through base material and board architecture optimization also is reviewed. Impact of buildup and chip positioning is studied through use of torsion testing and in situ PCB strain measurement. (IPC Apex, April 2010)

Market Trends “Trends, Business Models and Entry Modes in MedTech Manufacturing – China” Author: Tsz-Yin Chang; Abstract: China’s medical equipment market was $6.16 billion in 2009 and is expected to reach $10.18 billion in 2014, an 11.2% compound annual growth rate. Exports reached $5.3 billion in 2007, up 28% over 2006, mainly to the US (25.3%) and Japan (12.6%). Some 13,400 companies were building medical equipment in China as of 2008, and laws passed in 2009 push for a new infrastructure to address chronic domestic medical industry concerns. More than 2,000 hospitals will be established, as well as three medical science/biotech research parks. Siemens, Philips and GE are among the major multinational companies setting up large medical product development campuses in the country. (MedTech Manufacturing Conference, March 2010)

PWB Reliability

This column provides abstracts from recent industry conferences and company white papers. With the amount of information increasing, our goal is to provide an added opportunity for readers to keep abreast of technology and business trends. 48

“Effects of Solder Mask on Electrochemical Migration of Tin-Lead and Lead-Free Boards” Authors: Xiaofei He, Michael H. Azarian and Dr. Michael G. Pecht; Abstract: Solder mask’s mechanical and thermal properties have been widely reported, but systematic studies of their influence on electrochemical migration have been few. This paper presents results of temperature-humidity-bias (THB) testing of more than 1000 hr. duration at 40V, 65°C, and 88% relative humidity for comparative evaluation of ECM on circuit boards with and without a solder mask. The boards were HASL-finished and wave-soldered using a no-clean, low-solids flux. Besides primarily assessing effects of


solder mask on ECM, effects of solder alloy composition (eutectic SnPb versus Sn3.0Ag0.5Cu) were also investigated. In situ monitoring of SIR was performed throughout these tests. Optical microscopy and scanning electron microscopy were employed to examine the correlation between the physical attributes of dendrites and the measured SIR, as well as to evaluate the effects of solder mask and solder alloy on ECM. Ion chromatography was conducted to measure contaminant levels on the surface of the PCBs. Elemental mapping by energy dispersive x-ray spectroscopy was employed to identify the migrating species and their distributions and morphologies within the dendrites. As expected, the use of a solder mask resulted in higher SIR, but a dramatic difference was observed in its effect on dendritic growth and characteristic life. (IPC Apex, April 2010)

Wave Solder Joint Troubleshooting “Copper Tin Intermetallic Crystals and Their Role in the Formation of Microbridges between the Leads of Hand Reworked Fine Pitch Components” Author: Jeff Kukelhan Abstract: During wave-soldering exposure, copper from through-holes, surface-mount lands and component leads continually dissolves into the molten solder. Unless solder in the reservoir is regularly changed, dissolved copper eventually reaches a point of saturation, and orthorhombic Cu6Sn5 crystals begin to precipitate out of the molten solder, causing it to become gritty and sluggish. Solder drawn from such a saturated wave solder pot can solidify into joints whose surface finish exhibits many needle-like metallic protrusions. These protrusions are, in fact, orthorhombic Cu6Sn5 crystals. BAE Systems has determined that this same phenomenon is responsible for the formation of nearly invisible intermetallic microbridges between fine-pitch surface-mount component leads. They form when a solder bridge from a surface-mount paste reflow operation is handreworked with a soldering iron and copper desoldering braid. This paper documents several short circuit failures caused by this phenomenon, the investigation that identified the root cause of the problem, and the rework techniques that can be used to prevent it. (IPC Apex, April 2010) CA

august 2010

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Circuit assembly 2010  

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Circuit assembly 2010