PCB is the support of circuit components and components in electronic products. Inikeza ukuxhumana kagesi phakathi kwezinto zesekethe namadivayisi. Ngokuthuthuka okusheshayo kobuchwepheshe kagesi, ukuminyana kwe-PGB kuya ngokuya kukhula. Amandla we-PCB design ukumelana nokuphazanyiswa enza umehluko omkhulu. Ngakho-ke, ngo-PCB design. Izimiso ezijwayelekile zokwakhiwa kwe-PCB kufanele zilandelwe futhi nezidingo zedizayini yokulwa nokuphazamiseka kufanele kuhlangatshezwane nayo.

Izimiso ezijwayelekile ze-PCB design

Ukuhlelwa kwezingxenye nezintambo kubalulekile ekusebenzeni kahle kwamasekethe kagesi. For good design quality. I-PCB enezindleko eziphansi kufanele ilandele lezi zimiso ezijwayelekile ezilandelayo:

1. Isakhiwo

Okokuqala, kuyadingeka ukucabanga ngosayizi we-PCB kukhulu kakhulu. Lapho ubukhulu be-PCB bukhulu kakhulu, ulayini ophrintiwe mude, i-impedance iyanda, ikhono lokulwa nomsindo liyancipha, futhi izindleko ziyanda. Mncane kakhulu, ukushabalalisa ukushisa akukuhle, futhi imigqa esondelene nayo kungenzeka iphazanyiswe. Ngemuva kokunquma usayizi we-PCB. Bese thola izingxenye ezikhethekile. Ekugcineni, ngokuya ngeyunithi esebenzayo yesekethe, zonke izingxenye zesekethe zibekiwe.

Bheka lezi zimiso ezilandelayo lapho unquma indawo yezinto ezikhethekile:

(1) Fushanisa ukuxhumana phakathi kwezinto ezinemvamisa ephezulu ngangokunokwenzeka, bese uzama ukunciphisa amapharamitha wokusabalalisa nokuphazamiseka kwe-electromagnetic phakathi komunye nomunye. Izinto eziphazamiseke kalula akumele zisondelane kakhulu, futhi izinto zokufaka nezokukhipha kufanele zikude ngangokunokwenzeka.

(2) Kungahle kube khona umehluko omkhulu ongaba khona phakathi kwezinye izinto noma izintambo, ngakho-ke ibanga phakathi kwazo kufanele lenyuswe ukuze kugwenywe ngengozi isifunda esifushane esibangelwe ukukhishwa. Izinto ezinamandla amakhulu kufanele zibekwe ngangokunokwenzeka ezindaweni ezingafinyeleleki kalula ngesandla ngesikhathi sokulungisa iphutha.

(3) Izinto ezinesisindo esidlula i-15g. Kufanele iboshwe bese ishiselwa. Lokho kukhulu futhi kuyasinda. Izinto ezinenani eliphakeme le-calorific akufanele zifakwe ebhodini eliphrintiwe, kepha kwi-chassis yawo wonke umshini, futhi nenkinga yokushiswa kokushisa kufanele ibhekwe. Izinto ezishisayo kufanele zigcinwe kude nezinto zokushisa.

(4) ye-potentiometer. Ikhoyili ye-inductor eguquguqukayo. Variable capacitor. Ukuhlelwa kwezinto eziguquguqukayo njenge-microswitch kufanele kubheke izidingo zokwakhiwa kwawo wonke umshini. Uma ukulungiswa umshini, kufanele ibekwe ebhodini ephrintiwe ngenhla lula ukulungisa indawo; Uma umshini ulungiswa ngaphandle, isikhundla sawo kufanele sivumelane nesimo sebhande lokulungisa kuphaneli ye-chassis.

(5) Isikhundla esiphethwe yimbobo yokuma kanye nebakaki lokulungisa lever yokuphrinta kufanele sibekelwe eceleni.

Ngokweyunithi esebenzayo yesekethe. Ukuhlelwa kwazo zonke izingxenye zesekethe kuzothobela le migomo elandelayo:

(1) Hlela indawo yeyunithi ngayinye yesekethe esebenzayo ngokuya ngenqubo yesekethe, ukuze ukwakheka kube lula ukugeleza kwesiginali futhi isiginali igcina indlela efanayo ngangokunokwenzeka.

(2) Ezingxenyeni eziyinhloko zesekethe ngalinye elisebenzayo njengesikhungo, elizungezile ukwenza ukwakheka. Izingxenye kufanele zifane. Futhi kucocekile. Ihlelwe ngokuqinile kwi-PCB. Nciphisa futhi unciphise ukuhola nokuxhumana phakathi kwezinto.

(3) For circuits working at high frequencies, the distributed parameters between components should be considered. Kumasekethe ajwayelekile, izingxenye kufanele zihlelwe ngokufana ngangokunokwenzeka. Ngale ndlela, hhayi kuphela enhle. Futhi kulula ukuhlangana nokuhlanganisa.

(4) Izingxenye ezisemaphethelweni ebhodi lesifunda, ngokuvamile ezingekho ngaphansi kuka-2mm ukusuka emaphethelweni webhodi lesifunda. Ukuma okuhle kwebhodi lesifunda kungunxande. Isilinganiso sobude nobubanzi ngu-3: 20 no-4: 3. Usayizi webhodi lesifunda mkhulu kune-200x150mm. Ukucatshangelwa kufanele kunikezwe amandla womshini webhodi lesifunda.

2. Intambo

Imigomo ye-wiring imi kanje:

(1) Parallel wires at the input and output terminals should be avoided as far as possible. Kungcono ukufaka ucingo oluphansi phakathi kwezintambo ukugwema ukuhlangana kwempendulo.

(2) Ububanzi obuncane bocingo oluphrintiwe bunqunywa kakhulu ngamandla wokunamathela phakathi kocingo kanye ne-substrate evikela kanye nenani lamanje eligeleza ngabo.

Lapho ukushuba kocwecwe lwethusi kungu-0.05mm nobubanzi bungu-1 ~ 15mm. Okwamanje nge-2A, izinga lokushisa ngeke libe ngaphezu kuka-3 ℃, ngakho-ke ububanzi bocingo obungu-1.5mm bungahlangabezana nezidingo. Kumasekethe ahlanganisiwe, ikakhulukazi amasekethe edijithali, ngokuvamile kukhethwa ububanzi be-0.02 ~ 0.3mm. Vele, sebenzisa umugqa obanzi ngangokunokwenzeka. Ikakhulukazi izintambo zamandla nezintambo zomhlabathi.

Isikhala esincane sezintambo sinqunywa kakhulu ukumelana namandla wokwahlukanisa namandla okuwohloka phakathi kwezintambo esimweni esibi kakhulu. Kumasekethe ahlanganisiwe, ikakhulukazi amasekethe edijithali, inqobo nje uma inqubo ivumela, isikhala singaba sincane njengo-5 ~ 8mm.

(3) Okuphrintiwe kwentambo okugoqiwe ngokuvamile kuthatha i-arc eyindilinga, futhi i-Angle engakwesokudla noma i-Angle efakwe kumjikelezo omkhulu wesifunda izothinta ukusebenza kukagesi. Ngaphezu kwalokho, zama ukugwema ukusebenzisa izindawo ezinkulu zocwecwe lwethusi, kungenjalo. When heated for a long time, copper foil expands and falls off easily. Lapho kufanele kusetshenziswe izindawo ezinkulu zoqweqwe lwethusi, kungcono ukusebenzisa igridi. Lokhu kuvumela ukususwa kocwecwe lwethusi kanye nokuhlanganiswa kwe-substrate phakathi kokushisa okukhiqizwa yigesi eguquguqukayo.

3. Ipuleti lokushisela

Umgodi ophakathi wephedi kufanele ube mkhulu khudlwana kunobubanzi bomthofu wedivayisi. Iphedi enkulu kakhulu kulula ukwakha i-welding ebonakalayo. Ububanzi bePad elingaphandle D imvamisa abukho ngaphansi kuka (D +1.2) mm, lapho uD kungumbobo wokuhola. Kumasekhethi edijithali aphezulu, ubukhulu obuncane bephedi buyathandeka (D +1.0) mm.

I-PCB nezinyathelo zokulwa nokuphazamiseka

Idizayini yokulwa nokuphazamiseka yebhodi lesifunda ephrintiwe isondelene kakhulu nesekethe elithile. Lapha kuchazwe izinyathelo ezimbalwa ezijwayelekile zokwakhiwa kokulwa nokuphazamiseka kwe-PCB.

1. Idizayini yekhebuli yamandla

Ngokuya ngosayizi webhodi yesifunda ephrintiwe njengamanje, ngangokunokwenzeka ukwandisa ububanzi bolayini wamandla, ukunciphisa ukumelana kweluphu. Ngesikhathi esifanayo. Yenza intambo yamandla. Ukuqondiswa kocingo lomhlabathi kuyahambisana nokuqondiswa kokudluliswa kwedatha, okusiza ukukhulisa ukumelana nomsindo.

2.Lot design

Umgomo wedizayini yocingo lomhlabathi uthi:

(1) Umhlabathi wedijithali uhlukaniswe nomhlabathi we-analog. Uma kunombili wesekethe onengqondo futhi oqondile ebhodini lesifunda, wagcine ehlukane ngangokunokwenzeka. Umhlabathi wesekethe elinemvamisa ephansi kufanele wamukele iphuzu elilodwa lokugxila ngokulingana ngangokunokwenzeka. Lapho i-wiring yangempela inzima, ingxenye yesifunda ingaxhunywa ochungechungeni bese kuba nokufana okufanayo. Imvamisa yesekethe ephezulu kufanele isebenzise uchungechunge lwamaphoyinti amaningi, isisekelo kufanele sibe sifushane futhi siqashe, izinto ezinemvamisa ephezulu zizungeze ngangokunokwenzeka ngendawo enkulu ye-gril foil.

(2) Ucingo lokugxila kufanele lube lukhulu ngangokunokwenzeka. Uma ulayini wokubeka phansi umude kakhulu, isisekelo esingaba khona soshintsho samanje, ukuze ukusebenza okulwa nomsindo kuncishiswe. Ucingo lokumisa kufanele lube lujiyile ukuze lukwazi ukudlula kathathu njengamanje okuvumelekile ebhodini eliphrintiwe. Uma kunokwenzeka, ikhebuli lokugxila kufanele libe likhulu kuno-2 mm kuye ku-3mm.

(3) Intambo yomhlabathi yakha iluphu evaliwe. Most of the printed board composed only of digital circuit can improve the anti-noise ability of the grounding circuit.

3. Decoupling capacitor ukumiswa

Enye yemikhuba ejwayelekile ekwakhiweni kwe-PCB ukusebenzisa ama-capacitor wokuqothula afanele engxenyeni ngayinye eyinhloko yebhodi eliphrintiwe. Umgomo wokumiswa ojwayelekile we-decoupling capacitor ngu:

(1) Isiphetho sokufaka amandla sixhunywe ne-electrolytic capacitor ye-10 ~ 100uF. Uma kunokwenzeka, kungcono ukuxhuma i-100uF noma ngaphezulu.

(2), i-chip ngayinye ye-IC kufanele ifakwe i-ceramic capacitor engu-0.01pF. Uma isikhala sebhodi esiphrintiwe singanele, i-1 ~ 10pF capacitor ingahlelwa ngayo yonke i-4 ~ 8 chips.

(3) Ikhono lokulwa nomsindo alinamandla. Kwamadivayisi anezinguquko ezinkulu zamandla ngesikhathi sokuvala, njenge-RAM.Amadivayisi wememori we-ROM, i-decoupling capacitor kufanele ixhunywe ngqo phakathi kolayini wamandla nolayini womhlaba we-chip.

(4) Umholi we-capacitor akakwazi ukuba made kakhulu, ikakhulukazi i-high-frequency bypass capacitor ayikwazi ukuhola. Ngaphezu kwalokho, amaphuzu amabili alandelayo kufanele aqashelwe:

(1 Kukhona oxhumana naye ebhodini eliphrintiwe. Edluliselwe. Ukukhishwa okukhulu kwe-spark kuzokwenziwa lapho kusebenza izinkinobho nezinye izinto, futhi isifunda se-RC esiboniswe kulo mdwebo onamathiselwe kumele sisetshenziselwe ukuncela okukhiphayo njengamanje. Ngokuvamile, i-R iyi-1 ~ 2K, kanti i-C ingu-2.2 ~ 47UF.

I-impedance yokufaka ye-2CMOS iphezulu kakhulu futhi iyazwela, ngakho-ke ukuphela okungasetshenziswanga kufanele kubekwe phansi noma kuxhunywe kunikezelo lwamandla oluvumayo.