Njengengxenye ebalulekile yemikhiqizo ye-elekthronikhi, ibhodi yesifunda ephrintiwe (I-PCB) idlala indima enkulu ekuqapheliseni ukusebenza kwemikhiqizo ye-elekthronikhi, okuholela ekubalulekeni okuya ngokuvelele kokuklanywa kwe-PCB, ngoba ukusebenza komklamo we-PCB kunquma ngqo ukusebenza nezindleko zemikhiqizo kagesi. Idizayini enhle ye-PCB ingagcina imikhiqizo ye-elekthronikhi ivela ezinkingeni eziningi, ngaleyo ndlela iqinisekise ukuthi imikhiqizo ingenziwa kahle futhi ihlangabezane nazo zonke izidingo zezicelo ezisebenzayo.

Kuzo zonke izinto ezifaka isandla ekwakhiweni kwe-PCB, iDesign yokukhiqiza (DFM) ibaluleke impela ngoba ixhumanisa ukwakhiwa kwe-PCB nokwenziwa kwe-PCB ukuze kutholakale izinkinga kusenesikhathi futhi kuzixazulule ngesikhathi sonke kumjikelezo wempilo yemikhiqizo kagesi. One myth is that the complexity of PCB design will increase as manufacturability of electronics is considered at the PCB design stage. In the design life cycle of electronic products, DFM can not only make electronic products participate in automatic production smoothly, and save labor costs in the manufacturing process, but also effectively shorten the manufacturing time to ensure the timely completion of the final electronic products.

Ukwenziwa kwe-PCB

Ngokuhlanganisa ukwenziwa kwemikhiqizo ne-PCB design, ukuklanywa kokukhiqiza kuyisici esiyinhloko esiholela ekukhiqizeni okusebenzayo, ikhwalithi ephezulu nezindleko eziphansi. The research of PCB manufacturability covers a wide range, usually divided into PCB manufacturing and PCB assembly.

LPCB production

For PCB manufacturing, the following aspects should be considered: PCB size, PCB shape, process edge and Mark point. Uma lezi zici zingacatshangelwa ngokuphelele esigabeni sokuklanywa kwe-PCB, imishini yokuzilolonga ye-chip ezenzakalelayo kungenzeka ingakwazi ukwamukela amabhodi we-PCB asetshenzisiwe ngaphandle kokuthi kuthathwe ezinye izindlela zokucubungula. Ukwenza izinto zibe zimbi kakhulu, amanye amapuleti awakwazi ukwenziwa ngokuzenzakalela kusetshenziswa ukushisela ngesandla. As a result, the manufacturing cycle will be longer and labor costs will increase.

1. PCB size

Isifaki ngasinye se-chip sinobukhulu baso be-PCB obufunayo, obuhluka ngokuya ngamapharamitha wesifaki ngasinye. Isibonelo, isifaki se-chip samukela usayizi omkhulu we-PCB ka-500mm * 450mm nosayizi omncane we-PCB ongu-30mm * 30mm. Lokhu akusho ukuthi asikwazi ukuphatha izingxenye zebhodi le-PCB ezincane kuno-30mm nge-30mm, futhi singathembela kumabhodi we-jigsaw lapho kudingeka osayizi abancane. Lapho ungathembela kuphela ekufakweni kwezandla kanye nezindleko zabasebenzi ziyenyuka nemijikelezo yokukhiqiza ingalawuleki, imishini ye-chip SMT ayisoze yamukela amabhodi e-PCB amakhulu kakhulu noma amancane kakhulu. Therefore, in the PCB design stage, the PCB size requirements set by automatic installation and manufacturing must be fully considered, and it must be controlled within the effective range.

Lesi sibalo esilandelayo sibonisa idokhumenti yokwakhiwa kwebhodi le-PCB eligcwaliswe yi-software ye-Huaqiu DFM. Njengebhodi elingu-5 × 2, iyunithi ngayinye yesikwele ingcezu eyodwa, elinganisa u-50mm ngo-20mm. The connection between each unit is achieved by V-cut/V-scoring technology. In this image, the entire square is shown with a final size of 100mm by 100mm. Ngokuya ngezidingo ezingenhla, kungaphethwa ngokuthi usayizi webhodi ungaphakathi kwebanga elamukelekayo.

2. PCB shape

In addition to PCB size, all chip SMT machines have requirements for PCB shape. I-PCB ejwayelekile kufanele ibe yindilinga ngokuma okunobude obude nobubanzi be-4: 3 noma 5: 4 (okuhle kakhulu). If the PCB is irregularly shaped, additional measures must be taken prior to SMT assembly, resulting in increased costs. Ukuvimbela lokhu ukuthi kungenzeki, i-PCB kumele yakhelwe ngendlela efanayo ngesikhathi sesigaba sokuklanywa kwe-PCB ukuhlangabezana nezidingo ze-SMT. Noma kunjalo, lokhu kunzima ukukwenza lapho usebenza. Lapho ukwakheka kwemikhiqizo ethile ye-elekthronikhi kufanele kungalingani, izimbobo zezitembu kufanele zisetshenziselwe ukunika i-PCB yokugcina isimo esejwayelekile. Lapho kuhlanganisiwe, ama-baffles asizayo angasuswa ku-PCB ukuhlangabezana nezidingo zokufaka ezizenzakalelayo nezikhala.

Isithombe esingezansi sikhombisa i-PCB enesimo esingajwayelekile, futhi umphetho wokucubungula ungezwa yi-software ye-Huaqiu DFM. The whole circuit board size is 80mm * 52mm, and the square area is the size of the actual PCB. The size of the upper right corner area is 40mm by 20mm, which is the auxiliary craft edge produced by the bridge of the stamp hole.

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Inqubo yohlangothi

To meet the requirements of automatic manufacturing, process edges must be placed on the PCB to secure the PCB.

Esigabeni sokuklanywa kwe-PCB, 5mm ebanzi yenqubo onqenqemeni kufanele ibekelwe eceleni kusengaphambili, ngaphandle kokushiya noma yiziphi izingxenye nentambo. Umhlahlandlela wezobuchwepheshe uvame ukubekwa ohlangothini olufushane lwe-PCB, kepha uhlangothi olufushane lungakhethwa lapho isilinganiso sesici sidlula i-80%. Ngemuva komhlangano, umkhawulo wenqubo ungasuswa njengeqhaza lokukhiqiza elisizayo.

4. Mark point

For PCBS with components installed, Mark points should be added as a common reference point to ensure that component locations are accurately determined for each assembly device. Ngakho-ke, amaphuzu kaMark yizilinganiso zokukhiqiza ze-SMT ezidingekayo ekukhiqizeni okuzenzakalelayo.

Components require 2 Mark points and PCBS require 3 Mark points. These marks should be placed on the edges of the PCB board and cover all SMT components. Ibanga lesikhungo phakathi kweMark point kanye ne-plate edge kufanele okungenani libe ngu-5mm. Okwe-PCBS okunezinxenye ze-SMT ezinamacala amabili, amaphuzu kaMark kufanele abekwe ezinhlangothini zombili. If the components are too close together to place Mark points on the board, they can be placed on the edge of the process.

LPCB assembly

Inhlangano ye-PCB, noma i-PCBA ngamafuphi, empeleni inqubo yezingxenye zokushisela kumabhodi angenalutho. Ukuze uhlangabezane nezidingo zokukhiqiza okuzenzakalelayo, inhlangano ye-PCB inezidingo ezithile zomhlangano wephakheji nokuhlelwa komhlangano.

1. Ukupakisha izingxenye

Ngesikhathi sokuklanywa kwe-PCBA, uma amaphakheji wezinto angahlangabezani namazinga afanele futhi izingxenye zisondelene kakhulu, ukufakwa okuzenzakalelayo ngeke kwenzeke.

Ukuze kutholakale okusemaphaketheni okuhamba phambili, isoftware yokwakha eyi-EDA kufanele isetshenziselwe ukuhambisana nezindinganiso zomhlaba wonke zokupakisha. During PCB design, the aerial view area must not overlap with other areas, and the automatic IC SMT machine will be able to accurately identify and mount the surface.

2. Component layout

Ukuhlelwa kwento kungumsebenzi obalulekile ekwakhiweni kwe-PCB ngoba ukusebenza kwayo kuhlobene ngqo nobunzima bokubukeka kwe-PCB nenqubo yokukhiqiza.

Ngesikhathi sokuhlelwa kwengxenye, izindawo zomhlangano zezingxenye ze-SMD ne-THD kufanele zinqunywe. Lapha, sibeka umphambili we-PCB njengengxenye yohlangothi A kanye nangemuva njengengxenye yento B. The assembly layout should consider the assembly form, including single layer single package assembly, double layer single package assembly, single layer mixed package assembly, Side A mixed package and side B single package assembly and side A THD and side B SMD assembly. Ukuhlangana okuhlukile kudinga izinqubo namasu wokukhiqiza ahlukile. Therefore, in terms of component layout, the best component layout should be selected to make manufacturing simple and easy, so as to improve the manufacturing efficiency of the whole process.

In addition, consideration must be given to the orientation of component layout, spacing between components, heat dissipation, and component height.

Ngokuvamile, ukuqondiswa kwengxenye kufanele kuhambisane. Components are laid out in accordance with the principle of minimum tracking distance, based on which components with polarity markers should have uniform polarity directions, and components without polarity markers should be neatly aligned along the X or Y axis. Ukuphakama kwengxenye kufanele kube kuze kufike ku-4mm, futhi ukuqondiswa kokudlulisa phakathi kwengxenye ne-PCB kufanele kube ngu-90 °.

Ukwenza ngcono ijubane lokushisela lezinto nokwenza lula ukuhlolwa okulandelayo, isikhala phakathi kwezinto kufanele sivumelane. Izingxenye zenethiwekhi efanayo kufanele zisondelane futhi ibanga eliphephile kufanele lishiywe phakathi kwamanethiwekhi ahlukene ngokusho kokwehla kwamandla kagesi. Isilkisi nephedi akumele zidlulane, ngaphandle kwalokho izingxenye ngeke zifakwe.

Due to the actual operating temperature of the PCB and the thermal characteristics of the electrical components, heat dissipation should be considered. Ukuhlelwa kwezinto kufanele kugxile ekusakazekeni kokushisa. Uma kunesidingo, sebenzisa ifeni noma isinki yokushisa. Ama-radiator afanele kufanele akhethelwe izinto zamandla futhi izinto ezizwelayo ekushiseni kufanele zibekwe kude nokushisa. Ingxenye ephezulu kufanele ibekwe ngemuva kwengxenye ephansi.

Imininingwane engaphezulu kufanele igxile ku-PCB DFM, futhi isipiliyoni kufanele siqoqelwe ekusebenzeni. Isibonelo, izidingo zesakhiwo se-PCB esinejubane elikhulu zinezidingo ezikhethekile ze-impedance futhi kufanele kuxoxiswane ngazo nomkhiqizi webhodi ngaphambi kokwenziwa kwangempela ukunquma impedance nolwazi lokubeka. Ukuze ulungiselele ukukhiqizwa kumabhodi amancane we-PCB anezintambo eziminyene, ububanzi bokukhiqiza obuncane namandla wokukhiqiza ububanzi obudlula phakathi kufanele kuxoxwe ngawo nomenzi we-PCB ukuqinisekisa ukukhiqizwa okushelelayo kwalezi PCBS.