Njengenxalenye ebalulekileyo yeemveliso ze-elektroniki, ibhodi yesekethe eprintiweyo (I-PCB) idlala indima ebalulekileyo ekufezekiseni umsebenzi weemveliso ze-elektroniki, ezikhokelela ekubalulekeni ngokubaluleka koyilo lwe-PCB, kuba ukusebenza koyilo lwe-PCB kugqiba umsebenzi kunye neendleko zeemveliso ze-elektroniki. Uyilo oluhle lwe-PCB lunokugcina iimveliso zekhompyuter zivela kwiingxaki ezininzi, ngaloo ndlela kuqinisekiswe ukuba iimveliso zingenziwa kakuhle kwaye zihlangabezane nazo zonke iimfuno zezicelo ezisebenzayo.

Kuzo zonke izinto ezinegalelo kuyilo lwe-PCB, uyilo lokuvelisa (i-DFM) lubaluleke kakhulu kuba ludibanisa uyilo lwe-PCB kunye nemveliso ye-PCB ukuze ufumane iingxaki kwangoko kwaye uzisombulule ngexesha lonke kumjikelo wobomi weemveliso ze-elektroniki. 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.

Imveliso yePCB

Ngokudibanisa ukuveliswa kwemveliso kunye ne-PCB yoyilo, uyilo lokuvelisa yinto ephambili ekhokelela kwimveliso efanelekileyo, ekumgangatho ophezulu kunye neendleko eziphantsi. 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. Ukuba le miba ayithathelwa ngqalelo ngokupheleleyo kwinqanaba loyilo lwe-PCB, oomatshini bokulaminetha i-chip abazenzekelayo abanakho ukwamkela iibhodi ze-PCB esele zenziwe ngaphandle kokuba kuthathwe amanyathelo ongezelelweyo. Ukwenza izinto zibe mandundu, ezinye iipleyiti azinakwenziwa ngokuzenzekelayo kusetyenziswa iwelding yesandla. As a result, the manufacturing cycle will be longer and labor costs will increase.

1. PCB size

Isifakeli se-chip ngasinye sinesayizi yePCB enqwenelekayo, eyahluka ngokweeparameter zesifaki ngasinye. Umzekelo, isifaki se-chip samkela ubungakanani bePCB ubuninzi be-500mm * 450mm kunye nobuncinci bePBB ubukhulu be-30mm * 30mm. Oku akuthethi ukuba asinakho ukuphatha izinto zebhodi ye-PCB ezincinci kune-30mm nge-30mm, kwaye sinokuxhomekeka kwiibhodi zejigsaw xa kufuneka ubungakanani obuncinci. Xa unokuxhomekeka kuphela kufakelo lwencwadi kunye neendleko zabasebenzi ezikhulayo kwaye nemijikelo yemveliso ingalawuleki, oomatshini be-chip SMT abasoze bamkele iibhodi ze-PCB ezinkulu kakhulu okanye ezincinci 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.

Eli nani lilandelayo libonisa uxwebhu loyilo lwebhodi ye-PCB egqitywe yi-Huaqiu DFM software. Njengebhodi eyi-5 × 2, iyunithi nganye yesikwere sisiqwenga esinye, ukulinganisa i-50mm nge-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. Ngokwale mfuno ingentla, kunokugqitywa ekubeni ubungakanani bebhodi bukuluhlu olwamkelekileyo.

2. PCB shape

In addition to PCB size, all chip SMT machines have requirements for PCB shape. I-PCB eqhelekileyo ifanele ukuba yoxande ngokuma kunye nobude obude bubude be-4: 3 okanye 5: 4 (eyona ilungileyo). If the PCB is irregularly shaped, additional measures must be taken prior to SMT assembly, resulting in increased costs. Ukuthintela oku ukuba kungenzeki, i-PCB kufuneka yenzelwe imilo efanayo ngexesha lesigaba sokuyilwa kwe-PCB ukuhlangabezana neemfuno ze-SMT. Nangona kunjalo, kunzima ukwenza oko. Xa ubume bezinye iimveliso ze-elektroniki kufuneka zenziwe ngendlela engaqhelekanga, imingxunya yesitampu kufuneka isetyenziselwe ukunika iPCB yokugqibela imilo eqhelekileyo. Xa zihlanganisene, i-baffles ezingafunekiyo ezingafunekiyo zinokususwa kwi-PCB ukuhlangabezana nofakelo oluzenzekelayo kunye neemfuno zesithuba.

Lo mfanekiso ungezantsi ubonisa PCB kunye imilo mgaqweni, kwaye ngohlangothi processing yongezwa yi Huaqiu DFM software. 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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Icandelo lenkqubo

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

Kwinqanaba loyilo lwe-PCB, inkqubo ebanzi engama-5mm kufuneka ibekelwe bucala kwangaphambili, ngaphandle kokushiya naziphi na izinto kunye nokufaka iintambo. Isikhokelo sobuchwephesha sihlala sibekwe kwicala elifutshane le-PCB, kodwa icala elifutshane linokukhethwa xa umlinganiso wecala ungaphezulu kwe-80%. Emva kwendibano, umda wenkqubo ungasuswa njengendima yokuncedisa kwimveliso.

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. Ke ngoko, amanqaku kaMark ziimilinganiselo zokuvelisa ze-SMT ezifunekayo kwimveliso ezenzekelayo.

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. Umgama osembindini phakathi kwenqaku leMark kunye nomda wepleyiti kufuneka ubuncinci ube yi-5mm. Kwii-PCBS ezinamacala amabini e-SMT, amanqaku kaMark kufuneka abekwe macala omabini. 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

Indibano yePCB, okanye iPCBA ngokufutshane, enyanisweni yinkqubo yokuhambisa izinto kwiibhodi ezingenanto. Ukuze kuhlangatyezwane neemfuno zemveliso oluzenzekelayo, ibandla PCB unalo iimfuno ezithile package ibandla kunye noyilo ibandla.

1. Ukupakisha kwezinto

Ngexesha loyilo lwe-PCBA, ukuba iipakethi zecandelo azifezekisi imigangatho efanelekileyo kwaye izinto zisondele kakhulu kufakelo oluzenzekelayo alunakwenzeka.

Ukuze ufumane eyona nto iphambili ekupakishweni, isoftware yoyilo lwe-EDA kufuneka isetyenziselwe ukuthobela imigangatho yokupakisha yamanye amazwe. 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

Ubume becandelo ngumsebenzi obalulekileyo kuyilo lwe-PCB kuba ukusebenza kwayo kuhambelana ngqo nobunzima bokubonakala kwe-PCB kunye nenkqubo yokuvelisa.

Ngexesha lokuyilwa kwamacandelo, imiphezulu yendibano yezixhobo ze-SMD kunye ne-THD kufuneka zimiselwe. Apha, sibeka umphambili we-PCB njengecandelo A icala kunye nomva njengecandelo B kwicala. 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. Indibano eyahlukeneyo ifuna iinkqubo ezahlukeneyo kunye neendlela zobuchule. 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.

Ngokubanzi, ukuqhelaniswa kwecandelo kufuneka kungqinelane. 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 kwecandelo kufuneka kuye kwi-4mm, kwaye ulwalathiso lokuhambisa phakathi kwecandelo kunye ne-PCB kufuneka ibe yi-90 °.

Ukuphucula isantya se-welding sezinto kunye nokwenza uhlolo olulandelayo, isithuba phakathi kwezinto kufuneka sihambelane. Components in the same network should be close to each other and a safe distance should be left between different networks according to the voltage drop. Isilksi kunye nephedi akufuneki zidlule, kungenjalo izinto azizukufakwa.

Due to the actual operating temperature of the PCB and the thermal characteristics of the electrical components, heat dissipation should be considered. Ubume bezinto kufuneka bujolise ekusasazeni ubushushu. Ukuba kukho imfuneko, sebenzisa ifeni okanye isinki eshushu. Iiradiyetha ezifanelekileyo kufuneka zikhethelwe izixhobo zamandla kunye nezinto ezinobushushu kufuneka zibekwe kude nobushushu. Icandelo eliphezulu kufuneka libekwe emva kwento esezantsi.

Iinkcukacha ezithe kratya kufuneka zijolise kwi-DFM ye-PCB, kwaye amava kufuneka aqokelelwe ngokwenziwa. Umzekelo, iimfuno zesantya esiphezulu se-PCB kuyilo lweemfuno ezizodwa ze-impedance kwaye kufuneka kuxoxwe ngazo nomenzi webhodi ngaphambi kokwenza okwenyani ukumisela ukungalungelelani kunye nokubeka ulwazi. Ukulungiselela ukuveliswa kweebhodi ezincinci zePCB ngentambo eshinyeneyo, ubuncinci bobubanzi beentambo kunye nobungakanani bemingxunya yokuvelisa ubukhulu kufuneka kuxoxwe ngayo nomenzi wePCB ukuqinisekisa ukuveliswa kwezi PCBS.