Ephrintiwe wesifunda ibhodi (PCB) zitholakala cishe kuzo zonke izinhlobo zedivayisi kagesi. Uma kunezinto ze-elekthronikhi kucezu lwensiza, ziphinde zifakwe osayizi abahlukahlukene be-PCB. Ngaphezu kokulungisa izingxenye ezincane ezahlukahlukene, umsebenzi oyinhloko we-PCB ukuhlinzeka ukuxhumana ngogesi phakathi kwezingxenye. Njengoba imishini ye-elekthronikhi iba yinkimbinkimbi ngokwengeziwe, kudingeka izingxenye eziningi ngokwengeziwe, futhi izintambo nezingxenye ku-PCB ziba minyene ngokwengeziwe. I-PCB ejwayelekile ibukeka kanjena. Bare Board (without parts on it) is also often referred to as “Printed Wiring Board (PWB).

I-substrate yebhodi uqobo lwayo lwenziwe ngento efakiwe futhi emelana nokugoba. Izinto ezincane zomugqa ezingabonakala ngaphezulu i-foil yethusi. Ekuqaleni, ucwecwe lwethusi lumbozwe kulo lonke ibhodi, futhi ingxenye ephakathi iqoshwe enqubeni yokukhiqiza, futhi ingxenye esele iba yinethiwekhi yemigqa emincane. Le migqa ibizwa ngama-conductor noma ama-conductor futhi isetshenziselwa ukunikeza ukuxhumana ngogesi ezingxenyeni ze-PCB.

Ukuvikela izingxenye ze-PCB, sifaka izikhonkwane zazo ngqo ku-wiring. Ku-PCB eyisisekelo, izingxenye zigxile kolunye uhlangothi nezintambo zigxilwe kolunye. Ngakho-ke sidinga ukwenza izimbobo ebhodini ukuze izikhonkwane zikwazi ukudlula ebhodini ziye kolunye uhlangothi, ngakho-ke izikhonkwane zezingxenye zishiselwe kolunye uhlangothi. Ngenxa yalokhu, izinhlangothi zangaphambili nangemuva ze-PCB zibizwa ngokuthi i-Component Side ne-Solder Side ngokulandelana.

Uma kunezingxenye ku-PCB ezingasuswa noma zibuyiselwe emuva ngemuva kokwenziwa, iSokhethi lizosetshenziselwa ukufaka izingxenye. Ngoba isokhethi lishiselwe ngqo ebhodini, izingxenye zingahlukaniswa ngokuzithandela. I-plug ye-ZIF (Zero InserTIon Force) ivumela izingxenye ukuthi zifakwe futhi zisuswe kalula. Isigwedlo esiseduze kwesokhethi singabamba izingxenye zazo ngemuva kokuzifaka.

Ukuxhuma ama-PCBS amabili komunye nomunye, isixhumi esiseceleni sisetshenziswa kakhulu. Umunwe wegolide uqukethe amaphedi wethusi amaningi angenalutho empeleni ayingxenye yocingo lwe-PCB. Imvamisa, ukuxhuma, sifaka umunwe wegolide ku-PCB eyodwa ku-Slot efanelekile (evame ukubizwa ngokuthi yi-extension Slot) kwenye i-PCB. In computers, display cards, sound cards, and similar interface cards are connected to the motherboard by means of a gold finger.

Umbala oluhlaza noma onsundu ku-PCB umbala wesifihla-buso se-solder. Lolu ungqimba luyisivikelo esivikela insimbi yethusi futhi luvimbele izingxenye ukuthi zishiselwe endaweni engafanele. Esinye isikrini sikasilika sizophrintwa kusendlalelo sokumelana ne-solder. Imvamisa iphrintwa ngamagama nezimpawu (ikakhulukazi ezimhlophe) ukukhombisa ukuma kwezingxenye ebhodini. Screen printing surface is also known as icon surface

Inganekwane).

Amabhodi ayizinhlangothi ezimbili

Njengoba sishilo, kwi-PCB eyisisekelo, izingxenye zigxile kolunye uhlangothi nezintambo zigxilwe kolunye. Because the wire appears on only one side, we call this TYPE of PCB single-sided. Ngoba amapaneli angashadile ayenemikhawulo eminingi eqinile ekwakhiweni kwesekethe (ngoba kwakunohlangothi olulodwa kuphela, i-wiring yayingakwazi ukuwela futhi kwakudingeka ithathe indlela ehlukile), amasekethe okuqala kuphela ayesebenzisa lawo mabhodi.

Amabhodi anezinhlangothi ezimbili

Ibhodi lesifunda linezintambo ezinhlangothini zombili. Kepha ukuze usebenzise zombili izintambo, kufanele kube nokuxhumana okufanelekile kagesi phakathi kwezinhlangothi zombili. Leli “bhuloho” eliphakathi kwamasekethe libizwa ngokuthi umgodi wokuqondisa (i-VIA). Izimbobo zomhlahlandlela izimbobo ezincane ku-PCB ezigcwele noma ezifakwe insimbi ezingaxhunywa ezintanjeni ezinhlangothini zombili. Because a dual panel has twice the area of a single panel, and because the wiring can be interlaced (it can be wound around to the other side), it is better for more complex circuits than a single panel.

Amabhodi amaningi

Ukuze kwandiswe indawo engakwazi ukufakwa izintambo, kusetshenziswa amabhodi wiring angamacala amabili. Ibhodi le-multilayer lisebenzisa amaphaneli amaningi aphindwe kabili, futhi ungqimba lokufakwa lubekwa phakathi kwephaneli ngalinye bese linamathiselwe (licindezelwe). Inani lezendlalelo zebhodi limelela izendlalelo ezimbalwa zezintambo ezizimele, imvamisa inani lezendlalelo, kufaka phakathi izingqimba ezimbili ezingaphandle. Most motherboards are built with four to eight layers, but it is technically possible to build up to 100 layers of PCBS. Iningi labadlali abakhulu be-supercomputer basebenzisa izingqimba ezimbalwa zamabhodi womama, kepha seziyekile ukusebenza njengoba zingathathelwa indawo ngamaqoqo amakhompyutha ajwayelekile. Because the layers in a PCB are so tightly integrated, it’s not always easy to see the actual number, but if you look closely at the motherboard, you might be able to.

Imbobo yomhlahlandlela (i-VIA) esisanda kusho, uma ifakwa kuphaneli ephindwe kabili, kufanele ibe kulo lonke ibhodi

Kepha ku-multilayer, uma ufuna kuphela ukuxhuma eminye imigqa, izimbobo zomhlahlandlela zingachitha esinye isikhala somugqa kwezinye izingqimba. Buried vias and Blind vias avoid this problem because they only penetrate a few layers. Blind holes connect several layers of internal PCBS to surface PCBS without penetrating the entire board. Izimbobo ezingcwatshwe zixhunywe kwi-PCB yangaphakathi kuphela, ngakho ukukhanya akubonakali ebusweni.

Ku-PCB e-multilayer, ungqimba wonke uxhunywe ngqo ocingweni lomhlaba nokunikezwa kwamandla. Ngakho-ke sihlukanisa izingqimba njengeSiginali, Amandla noma iGround. If the parts on the PCB require different power supplies, they usually have more than two power and wire layers.

Ingxenye yokupakisha ubuchwepheshe

NgoHole Technology

The technique of placing parts on one side of the board and welding the pins to the other side is called “Through Hole Technology (THT)” encapsulation. Le ngxenye ithatha isikhala esiningi nomgodi owodwa kubholwa iphini ngalinye. Ngakho-ke amalunga abo empeleni athatha isikhala ezinhlangothini zombili, futhi amalunga we-solder makhulu ngokuqhathaniswa. Ngakolunye uhlangothi, izingxenye ze-THT zixhunywe kangcono ne-PCB kunezingxenye ze-Surface Mounted Technology (SMT), esizokhuluma ngazo ngokuhamba kwesikhathi. Amasokhethi afana nezisekelo ezinezintambo nezindawo zokuxhumana ezifanayo kudingeka ukuthi zibekezelele ingcindezi, ngakho-ke imvamisa amaphakheji we-THT.

I-Surface egibele ubuchwepheshe

Ezingxenyeni zeSurface Mounted Technology (SMT), iphini lishiselwe ohlangothini olufanayo nezingxenye. This technique does not drill holes in the PCB for each pin.

Izingxenye zokunamathela ezingaphezulu zingafakwa naphakathi kwezinhlangothi zombili.

I-SMT nayo inezingxenye ezincane kune-THT. Compared to PCB with THT parts, PCB with SMT technology is much denser. SMT package parts are also less expensive than THT’s. Ngakho-ke akumangazi ukuthi iningi lama-PCBS anamuhla angama-SMT.

Ngoba amalunga we-solder nezikhonkwane zezingxenye zincane kakhulu, kunzima kakhulu ukuzishisela ngesandla. However, given that current assembly is fully automated, this problem will only occur when repairing parts.

Inqubo yokuklama

Ekuklanyeni kwe-PCB, empeleni kunezinyathelo ezinde kakhulu ongazidlula ngaphambi kwezintambo ezisemthethweni. Okulandelayo inqubo eyinhloko yokwakhiwa:

The system specifications

Okokuqala, ukucaciswa kohlelo kwemishini ye-elekthronikhi kufanele kuhlelwe. It covers system functionality, cost constraints, size, operation and so on.

System function block diagram

Isinyathelo esilandelayo ukudala umdwebo webhulokhi osebenzayo wohlelo. Ubudlelwano phakathi kwezigcawu kufanele buphawuleke.

Divide the system into several PCBS

Ukwehlukanisa uhlelo lube ngama-PCBS amaningana akugcini nje ngokunciphisa usayizi, kepha futhi kunika uhlelo amandla okuthuthukisa nokushintsha izingxenye. The system function block diagram provides the basis for our segmentation. Computers, for example, can be divided into motherboards, display cards, sound cards, floppy disk drives, power supplies, and so on.

Thola indlela yokupakisha ezosetshenziswa kanye nosayizi we-PCB ngayinye

Once the technology and the number of circuits used for each PCB has been determined, the next step is to determine the size of the board. If the design is too large, then packaging technology will have to change, or re-split the action. Ikhwalithi nesivinini somdwebo wesifunda kufanele futhi kucatshangelwe lapho kukhethwa ubuchwepheshe.

Dweba imidwebo yesifunda yokuhlela yawo wonke ama-PCB

Imininingwane yokuxhumana phakathi kwezingxenye kufanele ikhonjiswe kumdwebo. I-PCB kuzo zonke izinhlelo kumele ichazwe, futhi iningi lazo lisebenzisa i-CAD (Computer Aided Design) njengamanje. Here is an example of a CircuitMakerTM design.

Umdwebo wokuhlelwa kwesifunda se-PCB

Preliminary design of simulation operation

To ensure that the designed circuit diagram works, it must first be simulated using computer software. Isoftware enjalo ingafunda amapulani futhi ikhombise ukuthi isifunda sisebenza kanjani ngezindlela eziningi. This is much more efficient than actually making a sample PCB and then measuring it manually.

Place the parts on the PCB

Indlela izingxenye ezibekwa ngayo incike ekutheni zixhunywe kanjani komunye nomunye. Kumele zixhunywe endleleni ngendlela esebenza kahle kakhulu. Izintambo ezisebenza kahle kusho izintambo ezifushane kakhulu nezingqimba ezimbalwa (eziphinde zinciphise inani lezimbobo eziqondisayo), kepha sizobuyela kulokhu ngentambo yangempela. Here is what the bus looks like on a PCB. Placement is important in order for each part to have perfect wiring.

Amathuba wokuhlola izintambo ngokusebenza okulungile ngejubane elikhulu

Enye i-software yanamuhla yekhompyutha ingabheka ukuthi ukubekwa kwengxenye ngayinye kungaxhunywa kahle yini, noma kubhekwe ukuthi kungasebenza kahle ngejubane eliphezulu. Lesi sinyathelo sibizwa ngokuhlela izingxenye, kepha ngeke siye kude kakhulu kulokhu. Uma kunenkinga ngokwakhiwa kwesifunda, izingxenye zingabuye zihlelwe kabusha ngaphambi kokuba isifunda sithunyelwe ensimini.

Export wesifunda on PCB

The connections in the sketch will now look like wiring in the field. Lesi sinyathelo sivame ukuzenzakalela ngokuphelele, yize izinguquko ezenziwa ngesandla zivame ukudingeka. Below is the wire template for 2 laminates. Imigqa ebomvu neluhlaza okwesibhakabhaka imele ungqimba wezingxenye ze-PCB kanye nongqimba lokushisela ngokulandelana. Umbhalo omhlophe nezikwele umele ukumaka ebusweni bokuphrinta kwesikrini. Amachashazi abomvu nemibuthano amele izimbobo zokuhola nokuqondisa. Ngakwesokudla kakhulu singabona umunwe wegolide endaweni yokushisela ye-PCB. The final composition of this PCB is often referred to as the working Artwork.

Idizayini ngayinye kufanele ihambisane neqoqo lemithetho, njengezikhala ezincane ezigcinwe phakathi kwemigqa, ubuncane bobubanzi bomugqa, neminye imikhawulo efanayo yokusebenza. Lokhu kuchazwa kuyahluka ngokuya ngejubane lesifunda, amandla esignali ezodluliselwa, ukuzwela kwesekethe ekusetshenzisweni kwamandla nangomsindo, kanye nekhwalithi yezinto zokusebenza nezinto zokwakha. If the strength of the current increases, the thickness of the wire must also increase. Ukuze wehlise izindleko ze-PCB, ngenkathi unciphisa inani lezendlalelo, kuyadingeka futhi ukunaka ukuthi ngabe le mithetho isahlangatshezwa yini. Uma kudingeka izingqimba ezingaphezu kwezingu-2, ungqimba wamandla nongqimba womhlaba kuvame ukusetshenziselwa ukugwema isignali yokudlulisela kusendlalelo sesiginali kuyathinteka, futhi kungasetshenziswa njengesihlangu sesendlalelo sesiginali.

Ucingo ngemuva kokuhlolwa kwesifunda

Ukuze uqiniseke ukuthi umugqa usebenza kahle ngemuva kocingo, kufanele uphumelele isivivinyo sokugcina. Lokhu kuhlolwa kubheka nokuxhumana okungalungile, futhi konke ukuxhumana kulandela umdwebo wesikimu.

Sungula bese ufaka ifayili

Ngoba njengamanje kunamathuluzi amaningi we-CAD wokuklama i-PCBS, abakhiqizi kumele babe nephrofayili ehlangabezana nezindinganiso ngaphambi kokwenza amabhodi. Kukhona ukucaciswa okujwayelekile okuningana, kepha okuvame kakhulu ukucaciswa kwamafayela eGerber. Iqoqo lamafayela eGerber lifaka phakathi uhlelo lwesiginali ngayinye, amandla noqweqwe lomhlabathi, uhlelo lwengqimba yokumelana ne-solder nendawo yokuphrinta kwesikrini, namafayela acacisiwe wokubhola nokushiya amakhaya.

Electromagnetic compatibility problem

Imishini kagesi engakhelwanga ukucaciselwa kwe-EMC kungenzeka ikhiphe amandla kagesi futhi iphazamise izinto eziseduze. I-EMC ibeka imikhawulo ephezulu ekuphazanyisweni kwe-electromagnetic (EMI), i-electromagnetic field (EMF) nokuphazamiseka kwemvamisa yomsakazo (RFI). Lo mthethonqubo ungaqinisekisa ukusebenza okujwayelekile kokusebenza kanye nezinye izinto eziseduze. I-EMC ibeka imingcele eqinile kunani lamandla angahlakazeka noma adluliswe lisuka kolunye ucingo luye kolunye, futhi yakhelwe ukunciphisa ukuthambekela kwe-EMF yangaphandle, i-EMI, i-RFI, njalonjalo. Ngamanye amagama, inhloso yalomthethonqubo ukuvimbela amandla kagesi angene noma aqhamuke kudivayisi. Le yinkinga enzima kakhulu ukuyixazulula, futhi imvamisa ixazululwa ngokusebenzisa amandla nokubeka izendlalelo, noma ukufaka i-PCBS emabhokisini ensimbi. The power and ground layers protect the signal layer from interference, and the metal box works equally well. Ngeke siye kude kakhulu kulezi zinkinga.

Isivinini esiphezulu sesekethe sincike ekulandelweni kwe-EMC. I-EMI yangaphakathi, njengokulahleka kwamanje phakathi kwabaqhubi, iyanda njengoba imvamisa ikhuphuka. Uma umehluko wamanje phakathi kwalokhu kukhulu kakhulu, qiniseka ukukhulisa ibanga phakathi kwabo. This also tells us how to avoid high voltage and minimize the current consumption of the circuit. Izinga lokubambezeleka kwentambo nalo libalulekile, ngakho-ke ubude obufushane, buba ngcono. Ngakho-ke i-PCB encane enentambo enhle izosebenza kangcono ngejubane eliphakeme kune-PCB enkulu.