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1、Design Guideline Training Revision:0,Design Guideline,Prepare by:Masa,Final Assembly Shielding issue,Led 燈不亮Root cause R2 掉落超音波case 壓下shielding 導致R2掉落Action:目前修改Shielding 焊接方式,目前修改Shielding 焊接方式,Final Assembly,腳長在規格內刺破防護罩Sony 48W 現正在導入短腳作業，以目前統計的工廠與廠商制程能力來看，元件腳長控制在2.5mm以內不會導致作業困難（且不會有剪腳現象）。產品過錫後的腳長變
2、化由兩部分變異引起，一為來料腳長變異，二為制程生產變異，目前很多廠商所能提供的原材料腳長隻能控制在+/-0.5mm左右（比如Y電容），工廠制程變異目前在+/-0.3mm左右，兩部分總體在+/-0.8mm(1.6mm)左右，加上元件出PCB腳長需大於0.8mm方不會有吃不上錫或包焊問題，故：1.6+0.8=2.4mm是目前工廠能管控的。,Final Assembly,CPOW121F13 IDWhen installing the case,we must push the SR to inside.This force also push the white part.So the weld
3、point maybe broken,Socket issue,AC inlet issue 無螺絲容易脫落,Layout,Solder Dam 斷裂造成容易溢錫,而Arcing 至Burnt,改善前,改善後,Layout,If wire after solder,layout can has a beach on the trace copper,Wave Solder,1.所有復合線材容易脫落.線材孔徑偏大與線材不匹配2.切板線被排插檔住.不能使用切板機切板邊,由于排插超出切板線,此邊條不能使用切板機切板邊.,按照以下方法設計之PCB不會影響到排插邊緣的板邊,SMD短路,裸銅焊盤之間距離過
4、窄且未加防焊線。,裸銅焊盤之間加防焊線，且封閉式裸銅盤。,SMD短路,因小板腳距過窄和焊盤設計有短路的隱患，阻擋拉錫,此種PAD設計不能很好的形成拉錫，有短路的隱患。,針對小板、晶體、修改裸銅焊盤形狀、加寬防焊漆如圖,單一晶體修改裸銅焊盤形狀和封閉式加寬防焊漆,SMD Layout,SMD,PAD大小.坐標是否對稱.（特別針對0603零件）PCB thickness是否介於0.54mmPCB Mark 是否有防呆處理?(對角Mark不得距定位孔距離相等)定位孔尺寸是否為3.6/3.8mm/-0.005mm.定位孔位置:是否距離板邊5mm+/-0.1mm.Component Mark:1.0/1
5、.2mm正方形或圓形,且中心3/4mm方形範圍內不得有綠漆或文字.Mark共兩個,位於零件對角,SMD,零件本體邊緣是否距離PCB板邊4mm以上.並不與被切板邊垂直.PCB Mark:1.0/1.2mm正方形或圓形,且中心3/4mm方形範圍內不得有綠漆或文字.Mark共三個,位於PCB角落零件極性方向是否一致,極性及文字.MARK標示是否清楚易檢驗鴛鴦板是否兩板對稱零件坐標相差值相同.板邊長.寬度是否一致.無差異.,SMD,Trace是否通過SMD件,厚度是否過高，導致零件放置後高蹺.絲印線是否在PCB零件合適的位置.不會有偏移情況金屬外殼零件下方及距本體3mm範圍內是否有via hole,t
6、est pad及線路,錫孔,線材、PFC等端子來料為B型或D型，插入圓孔時會造成錫孔,線材、PFC等端子來料嚴格要求O型,錫珠,接地pad梅花設計，脫錫效果不好，致錫珠產生,接地Pad由梅花狀改為條狀,短路,1.IC腳的PAD寬度大於IC腳寬度；2.PAD間白色防焊漆未添滿PAD間距；3.白色防焊漆未超出PAD長度,IC腳的PAD寬度大於IC腳寬度0.05+/-0.1mm；2.白色防焊漆添滿PAD間距；3.白色防焊漆應超出PAD長度（長度以空間決定）,短路,成排PIN過錫方向不當；柱波相互幹擾，不易拉錫,正確的過錫方向；減少柱波幹擾，pad間易拉錫,短路,中心孔距小於2.5mm的二個或多個相鄰
7、的pad，pad為圓點狀，當以錫波流向垂直方向過錫時，柱波相互幹擾，不易拉錫,中心孔距小於2.5mm的二個或多個相鄰的pad，pad設計成淚滴狀，減少柱波幹擾，pad間易拉錫,SMD短路,三個SMD元件之pad成三角分布，過錫方向如圖,PAD中間增加一條防焊漆,SMT,Diode&Transistor packages placed horizontal to wave solder or paste process used(在錫膏製程與過錫爐時二極體和電晶體需水平放置)(避免陰影效應 Shade effect),Solder Paste Prior To Wave Solder,Accep
8、table,Unacceptable,Acceptable,SMT,SMT pads have equal trace thermal properties to prevent thermal stress cracks(SMT每一個焊點須有相同的導熱特性以防止熱應力效應造成錫裂或零件破裂),Acceptable,Layout,所有AI(auto insertion)和需前置加工的部分均須使用淚滴型焊點,Manual Insertion,在手插件之前,電感類零件需垂直的支撐-Bobbin(繞線座)-PCB/epoxy solution(PCB/環氧樹酯)-Pre-insert and lea
9、d forming(not advised but sometimes required)(須事先合腳位及整腳),Manual Insertion,必須做散熱片傾斜或浮高的均方根RMS誤差分析並和工廠討論(關鍵的參數需經過認證),RSS Tolerance=1mm,Manual Insertion,變壓器的繞線鍍錫沾錫部分須符合規格,不能超過繞線軸(避免浮高或傾斜),Component specification clearly statesCritical to Quality workmanship criteria,Component specification does not cle
10、arly stateCritical to Quality workmanship criteria,Manual Insertion,橋式整流器需要穩固且垂直的支架或者要和底座成90度,周圍須有安全距離,不能有線材或零件的壓迫.,PCB Edge,Tilt over PCB edge,Manual Insertion,立式的零件須打k腳或是加散熱片或有合適的周圍零件支撐,且須滿足周圍零件,K-form must not exceed thecomponent body widthUnder body pre-form only required for plated thru holes,B
11、end must be at least 0.5 cm from component body,Long lead K-form required for all vertical axial devices,Manual Insertion,長腳的熱敏電阻Clip terminal leads(insert into HS clip final assy)(夾住端導線,於最後裝配時插入HS)-Add Teflon tubing support(prevent lead flexibility)(增加鐵弗龍套管),Felxible heat shrink tubing,Normally hig
12、h component density so preforming results in random shorts;flexible wires mean random protrusion,Non-flexible Teflon tubing,Manual Insertion,電晶體需先折彎角,水平插入PCB,避免導線長短腳或有彎腳,TO-92with holder(side view),Manual Insertion,SSW電壓選擇開關(110/220)需使用到鉤狀的接頭,Wire protrusionlength and anglesubject to processvariatio
13、n,Manual Insertion,All components have design clearance=1mm(visible);assemblies require RSS,Design clearance is 1mmVisible clearance,Wave Solder,大量生產的機種需特定設計過的過錫載具,試產數量在每個設計階段須有熱量數據圖表分析,Wave Solder,暴露的銅面必須是只有少/小塊的地方,Large area has higher surface retention for excess solder which can make shorts occu
14、r,Smaller areas have lower surface retention which reduces solder short risk,Wave Solder,磁性元件的二次測腳的Pad必須為design 6.1.10去降低熱傳導的比率,增加二次測腳位的沾錫能力,Wave Solder,Manual solder has two problems:1)Inter-metallic layer thickness is not controllable-Solder joint life-time is reduced-Flux wetting is not guarantee
15、d for seemles layer2)Neighboring SMD devices are effected-MLCC crack/tombstone-Inter-metallic layer thickness increased,Flux miss area and oxidation prevented solder bond,Inter-metallic layer naturally expands and is accelerated by heat,成品不希望用後焊,假如用手銲錫點 Occ=4,Det=5,且從其他銲錫接合至此手動錫點,此錫點最小須有0.5cm,Wave S
16、older,Not inserted component solder is clearly visible from single sided PCB component side(large via non-PTH),Not inserted component solder is not clearly visible from single sided PCB component side(large via non-PTH)Plated Thru holes are implementedHole has plug(clip terminal wire)Copper/tin pads
17、 are masked(not etched),單面板的灌穿孔沒有鋪銅,若零件未插到底,易造成錫裂),Wave Solder,任意2個焊錫點不能接觸到-避免原焊點產生變異,Variable soldering results,Predictable soldering results,Note:spacing can be very small,but pads should be separated,ICT,測試點不能在零件腳的焊點上,ICT pins stress solder jointsSolder joint height variableTear drop lead length
18、variableSMD component location is variable and fine pitch,Test point diameter 1mmSolder joint clearance 1mmTear drop clearance 5mm in 15 frontal area,15,ICT,spacer or Press pin 支撐柱需有零件位置標示在PCB silkscreen,PCB was not designed todistribute ICT stressCritical real estate area notdedicated to press pins
19、Factory press pin location isnot formally defined,ICT Pins,PCB was designed todistribute ICT stressCritical real estate area dedicated to press pinsFactory press pin location is formally defined,ICT1,ICT3,ICT2,ICT5,ICT4,PCB Comonent Side Silk Screen,ICT,PCB連板在分板時不能造成任何SMT零件的受力,故須在PCB板邊留適當間距或 0.5mm開槽
20、,V-Cut Panel seperation creates deflection stress in PCBStress is transferred to SMD and solder joints,An empty routed gap in the V-Cutnear the SMD prevents panel seperation deflection stressRequired for all SMD within 0.5cm of PCB edge,Final Assembly,All wires are design controlled to eliminate str
21、ess opportunity to all components and assemblies,Wires have opportunity to stress the control card,Wires have design control to prevent wire stress on the control card,Final Assembly,PSU的風扇網或通風孔朝外的那面,需有蜂窩樣式格柵封住,孔的直徑 0.5cm為最大值-防止昆蟲侵入,噴漆把守易脫漆,Handle Paint Peel Off,Inlet 周圍空間不夠,Inlet易浮高,Inlet floating,Inlet 周圍空間不夠,易導致Hi-pot,Inlet floating,L2擠破LED燈線,導致Hi-pot,
