SMT應(yīng)用方案分析

1、Internal UseCopyright MediaTek Inc. All rights reserved.2010/01Prepared by: Zhong XinApproved by: Rio ChiangE-mail: customer_Internal Usep MT6253介紹p What is aQFNp aQFNs Advantage vs TFBGA & QFNp 客戶量產(chǎn)問題集p 解決方法：PCB設(shè)計(jì)p 解決方法：鋼網(wǎng)設(shè)計(jì)p MT6253 (aQFN) Task Force Teamp Appendix1Internal Usep Mediatek將于2009年 Q4推

2、出首款GSM/GPRS單芯片方案MT6253p MT6253集成了數(shù)字基頻(DBB)，模擬基頻(ABB)，電源管理(PM)，射頻收發(fā)器(RF)。支持手機(jī)相機(jī)，高速USB，及D類音頻功放p MT6253=MT6225+MT6318+MT6139 p MT6253采用了新一代封裝技術(shù)(aQFN)MT6253N0930- BFALDSPK54-04-1G2-52MT6253正印2Internal Usen aQFN means Advanced QFNFeaturesLow Cost, Profile, and Light weightExcellent Thermal / Electrical P

3、erformanceExcellent Anti-drop-&-twist capability High I/O count up to 400Leadless & multi-row packageFree-form I/O designPower / Ground ringFine lead pitch 0.4mmGNDaQFNQFNTFBGA0.6-0.850.85-11-1.2PKG height (mm)3BT-RESINPAD (Cu)Solder Ball(SAC305)Solder MaskIMC layer, Au/Ni/SAC305aQFNTFBGAInternal Us

4、ePackage StructureaQFN (MT6253)TFBGA (MT6225 MT6318)QFN (MT6139)CostMediumHighLowThermalExcellentMediumExcellentElectricalExcellent (Lead-frame)Medium (Substrate)Excellent Anti-drop-&- twist ExcellentMediumExcellentPKG profileLowHighMediumWire bond-abilityGoodGoodMedium0.4mm PitchYesYesYesSMT abilit

5、yMedium (Few experience)Good (Solder ball)Good (Single-row)Rework Method1.Pre-solder (Fresh)2.Good SOP & Good YieldRe-ball (Mature)Solder Iron (Mature)4+Internal Use5截至3/12，18客戶已經(jīng)MP, 共生產(chǎn)802K. 平均良率99.3%Internal UsePCB Layout suggestion for E-pad area:推薦與IC接地焊盤相同尺寸 (即封裝庫(kù)1：1的面積比例)制作E-Pad.PCB Layout sug

6、gestion for Signal Pad： 推薦制作直徑為0.27mm的圓形焊盤(按封裝庫(kù)1:1制作)，精度控制在+/-0.02mm禁止在PCB表層使用鋪銅設(shè)計(jì).為保證接地性能，RF GND間建議做成網(wǎng)格狀走線或?qū)ND Pad連通到內(nèi)層的GND平面. 表層走線線寬盡量控制在0.2mm以內(nèi)。Pad與Pad之間留有阻焊橋.XE-Pad表層不鋪銅表層鋪銅6Internal UseStencil Opening suggestion for E-pad area:推薦鋼網(wǎng)開口面積為PCB E-Pad面積的30%40%.推薦鋼網(wǎng)開口邊緣距離PCB 焊盤邊緣0.2mm以上.建議將鋼網(wǎng)開口區(qū)域分割成為

7、邊長(zhǎng)小于2mm的大小相等方塊.Stencil Opening suggestion for Signal Pad： 推薦采用0.1mm厚的鋼網(wǎng).推薦Signal Pad開口邊長(zhǎng)（直徑）在0.27mm0.28mm之間.建議將其外形制作成方形倒角或圓形.E-PadMT6253ThicknessOpeningE-Pad0.1mm30%-40% AreaSignal Pad0.1mm0.27 0.28方形或圓形方形或圓形7Internal Usep PCB Design / Stencil Guidep aQFN Reliability Introductionp aQFN SMT 試產(chǎn)體驗(yàn)計(jì)劃試產(chǎn)體

8、驗(yàn)計(jì)劃8 (page A-1&2) (page A-3&6) (page A-7)Internal UseCopyright MediaTek Inc. All rights reserved.Copyright MediaTek Inc. All rights reserved.AppendixInternal UseLandTerminalLandLandCopperSolderThicknessOpening0.8mm0.4mmSquareSqure0.43mm0.53mm0.12mm0.48mm0.8mm0.4mmCircleCircle0.43mm0.53mm0.12mm0.48mm

9、0.65mm0.35mmSquareSqure0.375mm0.475mm0.12mm0.4mm0.65mm0.35mmCircleCircle0.375mm0.475mm0.12mm0.4mm0.5mm0.3mmSquareSqure0.325mm0.425mm0.1mm0.38mm0.5mm0.3mmCircleCircle0.325mm0.425mm0.1mm0.38mm0.5mm0.25mmSquareSqure0.275mm0.375mm0.1mm0.33mm0.5mm0.25mmCircleCircle0.275mm0.375mm0.1mm0.33mm0.475mm0.27mmCi

10、rcleCircle0.27mm0.3mm0.1mm0.27mm0.4mm0.2mmSquareSqure0.225mm0.3mm0.1mm0.225mm0.4mm0.2mmCircleCircle0.225mm0.3mm0.1mm0.225mmaQFN PackagePCB Pad DesignStencilA-1Internal UseMT6253 PKGPCB Land Pad DesignStencilLand PitchTerminal sizeLand ShapeLand ShapeCopper PadSolder MaskThicknessTerminalOpening0.475

11、0.27CircleCircle0.27(note1) 0.30(note2)0.10.23 0.27GNDOpeningThermal padSquare OpeningMatrixGap7X70.5(note3)8X80.250.33GNDUnit: mmNote:1.Pad尺寸與PCB板廠制作能力決定，此為推薦值，鋼網(wǎng)開口尺寸與此值強(qiáng)相關(guān)2.由PCB板廠制作能力決定，此為推薦值3.請(qǐng)?jiān)诜娇蛑苓叺筊=0.075mm的圓角A-2Internal UseA-3Internal UseA-4Internal UseA-5Internal UseA-6Internal Use客戶體驗(yàn)計(jì)劃客戶體驗(yàn)計(jì)劃Dummy ICPODProposal & Flow:1. 客戶成立客戶成立 TFT 小組小組, MSZ SA 與與CS 工程師將協(xié)同運(yùn)作工程師將協(xié)同運(yùn)作2. MTK提供提供 1K Dummy IC 與與 100 片片 Daisy PCB, 并請(qǐng)并請(qǐng) 客戶安排兩次客戶安排兩次 SMT 體