




已阅读5页,还剩23页未读, 继续免费阅读
版权说明:本文档由用户提供并上传,收益归属内容提供方,若内容存在侵权,请进行举报或认领
文档简介
10/01/2018,1,PCBA Presentation,10/01/2018,2,Content Structure,1, DFM/DFT Introduction,2,PCB Process and Material,3, PCBA Process and SAC305,4, ICT Testing,10/01/2018,3,1, DFM/DFT Introduction,1.1, Why we need to do DFx (DFM/DFT) analysis for PCB checking before we finalize the Gerber files?,First, the PCBs or PCBAs we design should match with PCB or PCBA supplier capability.,This is HAT PCB PanelizationDue to limited G PCB capabilities, 5mm clearance are required. But L PCB supplier can accept 2mm.,10/01/2018,4,Second, find some potential issues, In order to sure to avoid problems for PCB or product assembly.,A,Small issue: no UL logo and PCB supplier information on the PCB. Actually, these words were printed under heatsink.,D,Critical issue: H component cant be located in the center of magnetic Core. It affects PCBA assembly. Were thinking of some methods to fix it.,B,Balanced trace can prevent tombstone issue.,C, Thermal relief for PTH (Plated Through Hole) components insufficient solder issue.,10/01/2018,5,Draw a conclusion: Its necessary to do DFx analysis before Gerber out. The value of DFx in PCBA design and manufacturing can be factored directly into the cost to produce a printed circuit board or assembly. If the PCB/PCBA is manufactured with defects, the manufacturers or LEM will have to bear the high cost for defects and repairs. The only way those defects can be identified is by tests or assembly.,1.2, DFx Benefits,Improved designDecrease the time-to-marketDecrease product costIncrease market share and profitability,10/01/2018,6,1.3,How to implement DFx process,10/01/2018,7,1.4,DFM/DFT check Item,DFM check Item including:Tooling holeMounting holeFiducial marksPTH, NPTH sizeSolder side clearanceComponent clearanceCopper connectionSilkscreenSolder mask colorUL logo/PCB vendorBoard sizePost assembly issue,DFT check Item including:Test coverageTest points on bottom/top sideTest point styleTest points need to added or modified,10/01/2018,8,2, PCB Process and Material,2.1, PCB Material,Laminates,10/01/2018,9,2.2,PCB character explain,Tg: Glass transition temperature,Td: Delamination temperature,T260: Test at 260oC Testing for solderability,T288: Test at 288oC Testing for thermal stress at 3times10seconds,Dicy: Curing agent (Dicy-free for Anti-CAF ; Dicy-cure for process),Halogen: Halogen free good for CTE,Moisture absorption: below 5%,CTE: Temperature expansion coefficient,10/01/2018,10,2.3, RoHS and Reach,SnPb Melting point183oC SAC305 Melting point217oC ( Sn-3.0Ag-0.5Cu),RoHS : Restriction of the use of certain Hazardous Substances in electrical and electronic equipment. Take effect on 1 July 2006 and requires that such equipment must not contain the following chemicals:,Lead (Pb)Chromium VI (Cr 6+)Mercury (Hg)Cadmium (Cd) Polybrominated Biphenyls (PBB)Polybrominated diphenyl ethers (PBDE),10/01/2018,11,2.4, PCB Manufacture Process,10/01/2018,12,10/01/2018,13,10/01/2018,14,2.5,Laminate: 4 layer PCB,10/01/2018,15,The coupon indicates the number of the layer in a window. In case of a pressed multilayer, all layers are legible in the correct order.,10/01/2018,16,2.6, PCB surface finish,HAL SnAgCu Hot Air Solder Leveling, specified at LEM fileChemical Tin Second choice at LEM file Immersion SilverEasier to process ;sufficient barrel fill for PTH;good solderability;no contact issue during ICTtesting probe contact issue,CAF and Wicking issue ; Ionic contamination test; migrationCAF:Conductive Anode filament,10/01/2018,17,3, PCBA Process and SAC305,10/01/2018,18,3.2, SAC305,Why dont use Sn/Pb(63/37)?,Advantage: Excellent plating feasibility Well characterized and understand solderability performance Good deposit properties,assembly compatibility Melting point 183oC,Disadvantage: The only disadvantage is the TOXICITY of Pb,SAC305 Sn-3.0Ag-0.5Cu Melting point 217oCSN100C (Sn-Cu-Ni+Ge) Melting point 227oC,10/01/2018,19,3.3, Reflow profile,10/01/2018,20,Open/ShortAnalog ComponentsDigital ComponentsPower (Voltage testing),Coverage,4, ICT In Circuit Testing,In order to keep the product quality and find PCBA defect (Open-Short, Component value, Missing, Solder Voids,Polarity reverse) in a short time.,10/01/2018,21,4.1,Figure helps to understand ICT testing.,It looks like the same board, Actually it is different. So far ICT is the best way to find the different area .ICT can finish it in 1 second for this PCBA checking.,A,B,10/01/2018,22,Good,NG,ICT can find the different area in a short time.,A,B,10/01/2018,23,1, Short,NG Board,2, Component Missing Component Mismatch,3, Polarity reverse,NG phenomenon,10/01/2018,24,4.2,Guarding theory in complex circuit,Ip current will effect test result. So keep the Ip=0A.,Guarding theory keep the G Voltage equal 0V.,10/01/2018,25,4.3, Some components cant be detected.,RxR1*R2(R1+R2), R2 cant be detected,R=0.999ohm,Resistor parallel with resistor,Capacitor parallel with capacitor,C
温馨提示
- 1. 本站所有资源如无特殊说明,都需要本地电脑安装OFFICE2007和PDF阅读器。图纸软件为CAD,CAXA,PROE,UG,SolidWorks等.压缩文件请下载最新的WinRAR软件解压。
- 2. 本站的文档不包含任何第三方提供的附件图纸等,如果需要附件,请联系上传者。文件的所有权益归上传用户所有。
- 3. 本站RAR压缩包中若带图纸,网页内容里面会有图纸预览,若没有图纸预览就没有图纸。
- 4. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途。
- 5. 人人文库网仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对用户上传分享的文档内容本身不做任何修改或编辑,并不能对任何下载内容负责。
- 6. 下载文件中如有侵权或不适当内容,请与我们联系,我们立即纠正。
- 7. 本站不保证下载资源的准确性、安全性和完整性, 同时也不承担用户因使用这些下载资源对自己和他人造成任何形式的伤害或损失。
最新文档
- 电线电缆实验知识培训课件
- 5.1 圆柱说课稿-2025-2026学年初中数学人教版五四制六年级上册-人教版五四制2012
- 四、舞台坐标说课稿-2025-2026学年小学信息技术粤教版B版五年级上册-粤教版(B版)
- 任务三 安全地交流信息说课稿-2025-2026学年初中信息技术桂科版七年级上册-桂科版
- 厨具采购合同
- 其它合同教育扶贫项目协议书5篇
- 我劳动我快乐(说课稿)2023-2024学年初三下学期教育主题班会
- 2024-2025学年高中语文 第三单元 小说(2)12 失街亭说课稿 粤教版必修4
- 2025塑胶销售合同书
- 2025室内设计私人定制合同全面详细版
- 安徽省蚌埠市A层高中2025-2026学年高二上学期第一次联考(10月)英语试卷
- 2025年及未来5年中国高端照明灯具行业市场调查研究及发展战略规划报告
- 胸椎的解剖讲解
- 5.2 诚实守信 课件-2025-2026学年统编版道德与法治八年级上册
- 2026中科信公司校园招聘笔试模拟试题及答案解析
- 2025-2026学年第一学期苏教版二年级数学上册第一单元测试卷及答案
- 宿州市中石化2025秋招面试半结构化模拟题及答案炼油工艺技术岗
- Unit5MyhouseLesson1(课件)-剑桥国际少儿英语Kids'box预备级
- 2025山西阳泉平定县县属国有企业招聘100人笔试备考试题及答案解析
- 第五单元漫步经典第4课时《第九十四(惊愕)交响曲》教学设计-西大版初中音乐八年级上册
- 盐酸吉卡昔替尼片-临床用药解读
评论
0/150
提交评论