SMT应用方案分析

1、Internal UseCopyright MediaTek Inc. All rights reserved.2010/01Prepared by: Zhong XinApproved by: Rio ChiangE-mail: customer_Internal Usep MT6253介绍p What is aQFNp aQFNs Advantage vs TFBGA & QFNp 客户量产问题集p 解决方法：PCB设计p 解决方法：钢网设计p MT6253 (aQFN) Task Force Teamp Appendix1Internal Usep Mediatek将于2009年 Q4推

2、出首款GSM/GPRS单芯片方案MT6253p MT6253集成了数字基频(DBB)，模拟基频(ABB)，电源管理(PM)，射频收发器(RF)。支持手机相机，高速USB，及D类音频功放p MT6253=MT6225+MT6318+MT6139 p MT6253采用了新一代封装技术(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客户已经MP, 共生产802K. 平均良率99.3%Internal UsePCB Layout suggestion for E-pad area:推荐与IC接地焊盘相同尺寸 (即封装库1：1的面积比例)制作E-Pad.PCB Layout sug

6、gestion for Signal Pad： 推荐制作直径为0.27mm的圆形焊盘(按封装库1:1制作)，精度控制在+/-0.02mm禁止在PCB表层使用铺铜设计.为保证接地性能，RF GND间建议做成网格状走线或将GND Pad连通到内层的GND平面. 表层走线线宽尽量控制在0.2mm以内。Pad与Pad之间留有阻焊桥.XE-Pad表层不铺铜表层铺铜6Internal UseStencil Opening suggestion for E-pad area:推荐钢网开口面积为PCB E-Pad面积的30%40%.推荐钢网开口边缘距离PCB 焊盘边缘0.2mm以上.建议将钢网开口区域分割成为

7、边长小于2mm的大小相等方块.Stencil Opening suggestion for Signal Pad： 推荐采用0.1mm厚的钢网.推荐Signal Pad开口边长（直径）在0.27mm0.28mm之间.建议将其外形制作成方形倒角或圆形.E-PadMT6253ThicknessOpeningE-Pad0.1mm30%-40% AreaSignal Pad0.1mm0.27 0.28方形或圆形方形或圆形7Internal Usep PCB Design / Stencil Guidep aQFN Reliability Introductionp aQFN SMT 试产体验计划试产体

8、验计划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尺寸与PCB板厂制作能力决定，此为推荐值，钢网开口尺寸与此值强相关2.由PCB板厂制作能力决定，此为推荐值3.请在方框周边倒R=0.075mm的圆角A-2Internal UseA-3Internal UseA-4Internal UseA-5Internal UseA-6Internal Use客户体验计划客户体验计划Dummy ICPODProposal & Flow:1. 客户成立客户成立 TFT 小组小组, MSZ SA 与与CS 工程师将协同运作工程师将协同运作2. MTK提供提供 1K Dummy IC 与与 100 片片 Daisy PCB, 并请并请 客户安排两次客户安排两次 SMT 体