T3_REF_DDR3_8X4_V1_0_Layout_note.docx
T3_REF_DDR3_8X4_V1_O1.ayoutNote1Stackup-Impadence-TraceWidth-SixkupStruaureimpedanceRe<jutfmentsLayerTypeThckness(mil)Dk(WrthSimZ0)impedancespec(OhmS)ReferencelayerWidtrvspace(mil)SimZO(OhfnS)so*dermask05SM4251TOP1603oz÷patig50110%2452189010%245/75031±10%238/87985prepreq2942GND10.605ozcore40423SG10605<X50110%2&44502901%2&445/759032IOo=10%2&438/879892prepreq70454GND20.605(core4045SIG20.605(K50±10%547450290110%5&745/7590321±1%5&738/879892prepreq70456SIG31.60.5<50±10%74521890±10%745/7.59003IooI;10%738/8798.5core40427POWER10605<K8prepreq294BOTTOM0603oz+plabnqsokfermask0.5SM425Boardthickness3962走线宽度单端：外层走线线宽4mil,内层4mil。差分：外层走线线宽/线距为3.7/8.8mil；内层3.7/8.8mil0电源和地FanOUt线宽：>10miIe3间距单端：外层线与线的间距(AirGap)>8mil,内层28mil0差分线：到其他网络走线间距212mil0电源与地：到其他网络走线的间距N12mil°VREF：到其他网络走线的间距28mil°BGA区域里:线与线如里；线与SMDPIN4mil：线与过孔4mil04拓扑DQ：单点对单点DQSDQSB：单点对单点Ax、BAx>CAS、RAS、WE、CSx>ODTxxCKEx、RST：远端簇型F<600mil,E-F<+/-50mil<.对于四片颗粒：A,B<700mil,A-B<+/-50mil,C,D<900mil,C-D<+/-50mil4,CK、CKB：远端簇型对于四片颗粒：C,D,E,F<500mil,C-D<+/-50mil,E-F<+/-50mil,G,H<800mil,G-H<+/-50milo5等长DQO-7：相对于DQS0、DQSBO做等长，误差范围为+/-25milo过孔数一致。DQ8-15：相对于DQSl、DQSBl做等长,误差范围为+/-25mil,过孔数一致。DQ16-23：相对于DQS2、DQSB2做等长，误差范围为+/-25mil,过孔数一致。DQ24-31：相对于DQS3、DQSB3做等长，误差范围为+/-25mib过孔数一致。DQSx、DQSBx:相对于CK/CKB信号做等长，误差范围为+/-800miloAx、BAx、CAS>RAS、WE、CSxODTx、CKEx：相对于CK/CKB信号做等长，误差范围为+/-600mil°DQSX与DQSBX等长，等长误差范围为+/-IOmiLCK与CKB等长，等长误差范围为+/-IOmilo信号线做等长时要考虑过孔长度的影响电源、地平面平面比较完整，调整好过孔的位置、间距，减少对电源、地平面的破坏。平面断开处用走线连接电源、地平面同时也是信号的参考层要求，不能有信号线的参考层被割断的现象7滤波电容:对于单面布局：尽量靠近电源PIN放置，每个电容至少各一个电源过孔和地过孔。对于双面布局：最好能放置在电源管脚下方的PCB背面，每个电容至少各个电源过孔和地过孔。不同容值的电容均匀分布。1.DeclarationThisdocumentistheoriginalworkandcopyrightedpropertyofAllwinnerTechnology("Allwinner'').ReproductioninwholeorinpartmustobtainthewrittenapprovalofAllwinnerandgiveclearacknowledgementtothecopyrightowner.TheinformationfurnishedbyAllwinnerisbelievedtobeaccurateandreliable.Allwinnerreservestherighttomakechangesincircuitdesignand/orspecificationsatanytimewithoutnotice.Allwinnerdoesnotassumeanyresponsibilityandliabilityforitsuse.Norforanyinfringementsofpatentsorotherrightsofthethirdpartieswhichmayresultfromitsuse.NolicenseisgrantedbyimplicationorotherwiseunderanypatentorpatentrightsofAllwinner.Thisdatasheetneitherstatesnorimplieswarrantyofanykind,includingfitnessforanyparticularapplication.
