ASMediaASM1480PCIe3.0SignalSwitch Datasheet
GeneralDescription
ASM1480isa16to8channelmultiplexer/demultiplexerSwitchwithHi-Zoutputs. Thisdeviceisabi-directionalmultiplexesdifferentialsignaltooneoftwo correspondingoutputs.Thisdesignissuitableforcurrenthigh-speedapplicationup toPCI-ExpressRev.3.0.
Overview
Feature Description
Part Number ASM1480
FunctionPCIe30laneswitch(mux/demux)
Channels16differentialpairs(8bidirectionalswitches)
Application
PCIelanesharingorswitching(e.g.betweenCPUand M.2/PCIeslots)
MaxSpeedUpto8.0GT/s(PCIeGen3)
Voltage33Vpowersupply
Package42-pinTQFN
Features
Quickswitchforhighspeed,highbandwidthdifferentialprotocols
8channel,2:1Mux/DeMuxSwitchwithsingleenable
Package:42pinsTQFN
Leadfree,RoHscompliance.
VCCoperation:+33V
FunctionalDescription
TheASM1480provides8-channellaneswitching,typicallyimplementedas:
2:1bi-directionalswitchfordifferentialpairs(TX+/TX-,RX+/RX-)
AllowsPCIeroutingreconfigurationeg,switchingCPUPCIelanesbetweenadiscreteGPUand anM2SSD
ControlledbySEL(select)inputsignal,switchingbetweenSourceAorSourceB
Diagram:SimplifiedFunctionalBlock
HostPCIe←
PinoutandSignalDescription
Whilethefullpinoutisinthedatasheet,hereareessentialsignals:
PinNameDescription
SEL Logiccontrolinput;selectswhichpathisactive
A[0:7]+/-FirstPCIesource/destination(lanegroupA)
B[0:7]+/-SecondPCIesource/destination(lanegroupB)
Y[0:7]+/-CommonPCIeoutput/input(sharedpath)
VCC Powersupply(3.3V)
PinNameDescription
GND Ground
Eachdifferentialsignalisroutedthroughhigh-speedanalogswitches,preserving signalintegrityacrossPCIe30bandwidth
ElectricalCharacteristics
Parameter
MaxDataRate 8.0GT/s(PCIeGen3)
OnResistance(Ron) Typically<12Ω
Crosstalk <-20dBat4GHz
InsertionLoss -12dBtypicalat4GHz
PowerConsumption
Verylow,passiveroutingswitch
Applications
MotherboardPCIebifurcation(x16↔x8/x8,orx8/x4/x4)
M2SSDswitchingbetweenCPUlanesandchipset
NotebookplatformwithhybridGPU/SSDlanesharing
ServerboardPCIeexpansionwithswitchableresources
Thunderbolt/USB4-PCIebridgingapplications
PracticalImplementationNotes
ControlledviaaGPIOorembeddedcontrollerlogic(firmwaresetstheSELstate)
Routedifferentialpairswithmatchedlengthandimpedance(85Ωdifferential).
Avoidlongtracestubsorviasthatdegradesignalintegrity
Usedpassivelynoretimingorbuffering;signalintegritydependsonPCBdesign
Alternatives/Equivalents
WhiletheASM1480isthemostcommonfor8.0GT/sapplications,alternatives include:
Part Vendor Notes
PI3PCIE3415 DiodesInc. CompatiblePCIe3.0mux/demux
HD3SS3412 Texas Instruments 2-laneswitch,PCIe/SATA
PI2PCIE2215 DiodesInc Dual2-laneswitch
ASMedia
ASM1442 ASMedia Similarbutoldergen,lower speed