Ngemishini ye-elekthronikhi, inani elithile lokushisa likhiqizwa ngesikhathi sokusebenza, ukuze izinga lokushisa langaphakathi lemishini likhuphuke ngokushesha. Uma ukushisa kungachithwa ngesikhathi, okokusebenza kuzoqhubeka nokushisa, futhi idivayisi izohluleka ngenxa yokushisa ngokweqile. Ukuthembeka kwemishini kagesi Ukusebenza kuzokwehla.

Ngakho-ke, kubaluleke kakhulu ukuqhuba ukwelashwa okuhle kokukhipha ukushisa ku- ibhodi yesifunda. Ukuchithwa kokushisa kwebhodi lesifunda le-PCB kuyisixhumanisi esibaluleke kakhulu, ngakho-ke iyini inqubo yokukhipha ukushisa yebhodi lesifunda le-PCB, ake sikuxoxe ndawonye ngezansi.

1. Ukukhishwa kokushisa ngebhodi le-PCB ngokwalo Amabhodi e-PCB asetshenziswa kakhulu njengamanje ama-copper clad/epoxy glass cloth substrates noma ama-phenolic resin glass cloth substrates, kanye nenani elincane lamabhodi anezingubo zethusi asekelwe ephepheni.

Nakuba lawa ma-substrates anezakhiwo ezinhle kakhulu zikagesi kanye nezakhiwo zokucubungula, anokukhipha ukushisa okungekuhle. Njengomzila wokukhipha ukushisa wezingxenye ezishisa kakhulu, cishe akunakwenzeka ukulindela ukushisa okuvela ku-resin ye-PCB ngokwayo ukuqhuba ukushisa, kodwa ukukhipha ukushisa okuvela ebusweni bengxenye kuya emoyeni ozungezile.

Kodwa-ke, njengoba imikhiqizo ye-elekthronikhi ingene enkathini ye-miniaturization yezingxenye, ukuphakama okuphezulu, nokuhlanganiswa kokushisa okuphezulu, akwanele ukuthembela ebusweni bengxenye enendawo encane kakhulu ukuze kukhishwe ukushisa.

Ngesikhathi esifanayo, ngenxa yokusetshenziswa okubanzi kwezingxenye ze-surface mount ezifana ne-QFP ne-BGA, ukushisa okukhiqizwa yizingxenye kudluliselwa ebhodini le-PCB ngenani elikhulu. Ngakho-ke, indlela engcono kakhulu yokuxazulula ukuchithwa kokushisa ukuthuthukisa amandla okukhipha ukushisa kwe-PCB ngokwayo ethintana ngqo nesici sokushisa. Kuzodluliswa noma kukhishwe.

Engeza i-foil yethusi ekhipha ukushisa kanye ne-copper foil enendawo enkulu kagesi

Thermal nge

Ukuvezwa kwethusi ngemuva kwe-IC kunciphisa ukumelana nokushisa phakathi kwesikhumba sethusi nomoya.

Ukuhlelwa kwe-PCB

a. Beka idivayisi ezwela ukushisa endaweni yomoya obandayo.

b. Beka idivayisi yokuthola izinga lokushisa endaweni eshisa kakhulu.

c. Amadivayisi ebhodini elifanayo eliphrintiwe kufanele ahlelwe ngokusemandleni akho ngokuvumelana nenani lawo le-calorific kanye nezinga lokukhipha ukushisa. Amadivayisi anevelu ye-calorific ephansi noma ukumelana nokushisa okubi (njengama-transistors wesignali amancane, amasekhethi ahlanganisiwe ezinga elincane, ama-electrolytic capacitor, njll.) kufanele abekwe Ukugeleza okuphezulu kakhulu kokugeleza komoya okupholisa (ekungeneni), kanye namadivayisi anokushisa okukhulu. ukukhiqiza noma ukumelana nokushisa okuhle (njengama-transistors kagesi, amasekhethi amakhulu ahlanganisiwe, njll.) abekwe engxenyeni engezansi kakhulu yokugeleza komoya okupholisa.

d. Esiqondisweni esivundlile, amadivaysi anamandla aphezulu abekwe eduze nomkhawulo webhodi eliphrintiwe ngangokunokwenzeka ukuze unciphise indlela yokudlulisa ukushisa; ohlangothini oluqondile, amadivaysi anamandla aphezulu abekwe eduze nangaphezulu kwebhodi eliphrintiwe ngangokunokwenzeka ukuze kuncishiswe izinga lokushisa lamanye amadivaysi lapho lezi zisetshenziswa zisebenza Impact.

e. Ukuchithwa kokushisa kwebhodi eliphrintiwe kumishini ikakhulukazi kuncike ekugelezeni komoya, ngakho-ke indlela yokuhamba komoya kufanele ifundwe ngesikhathi sokuklama, futhi idivayisi noma ibhodi lesifunda eliphrintiwe kufanele lilungiselelwe ngokunengqondo. Lapho umoya ugeleza, uvame ukugeleza ezindaweni ezinokumelana okuphansi, ngakho-ke lapho ulungiselela amadivaysi ebhodini lesifunda eliphrintiwe, gwema ukushiya indawo yomoya enkulu endaweni ethile. Ukumiswa kwamabhodi esekethe aphrintiwe amaningi kuwo wonke umshini kufanele futhi kunake inkinga efanayo.

f. Idivayisi ezwelayo kumazinga okushisa ibekwe kangcono endaweni yokushisa ephansi kakhulu (njengaphansi kwedivayisi). Ungalokothi uyibeke ngaphezu kwedivayisi yokushisisa. Kungcono ukunyakazisa amadivaysi amaningi endizeni evundlile.

g. Hlela amadivayisi asebenzisa amandla aphezulu kakhulu kanye nokukhiqiza ukushisa okuphezulu kakhulu eduze nendawo engcono kakhulu yokuqeda ukushisa. Ungabeki izinto zokushisisa okuphezulu emakhoneni nasemaphethelweni azungezile ebhodi eliphrintiwe, ngaphandle uma kuhlelwe isinki sokushisa eduze kwayo. Lapho uklama isivimbeli samandla, khetha idivayisi enkulu ngangokunokwenzeka, futhi uyenze ibe nesikhala esanele sokukhipha ukushisa lapho ulungisa ukwakheka kwebhodi eliphrintiwe.

h. Isikhala sengxenye ephakanyisiwe:

Izindlela ezisebenzayo eziyi-10 zokukhipha ukushisa kwe-PCB

Izindlela ezisebenzayo eziyi-10 zokukhipha ukushisa kwe-PCB

2. Izingxenye ezikhiqiza ukushisa okuphezulu kanye nama-radiator namapuleti ahambisa ukushisa. Lapho izingxenye ezimbalwa ku-PCB zikhiqiza inani elikhulu lokushisa (ngaphansi kuka-3), isinki sokushisa noma ipayipi lokushisa lingangezwa ezingxenyeni ezikhiqiza ukushisa. Uma izinga lokushisa lingenakwehliswa, Irediyetha enefeni ingasetshenziswa ukuthuthukisa umphumela wokuqeda ukushisa.

Lapho inani lamadivayisi okushisa likhulu (ngaphezu kuka-3), isembozo esikhulu sokushabalalisa ukushisa (ibhodi) singasetshenziswa, okuwumshini wokushisa okhethekile owenziwe ngokwezifiso ngokwendawo nokuphakama kwedivayisi yokushisa ku-PCB noma iflethi elikhulu. usinki wokushisa Sika izindawo ezihlukene zobude bengxenye.

Isembozo sokukhipha ukushisa siboshelwe ngokuphelele ebusweni bengxenye, futhi sixhumene nengxenye ngayinye ukuze sikhiphe ukushisa. Nokho, umphumela wokukhipha ukushisa awumuhle ngenxa yokungaguquguquki okungekuhle kobude ngesikhathi sokuhlanganiswa nokushisela izingxenye. Ngokuvamile, isigaba esithambile sokushintsha i-thermal pad yengezwa phezu kwengxenye ukuze kuthuthukiswe umphumela wokulahla ukushisa.

3. Okokusebenza okwamukela ukupholisa komoya we-convection wamahhala, kungcono ukuhlela amasekhethi ahlanganisiwe (noma amanye amadivaysi) aqondile noma avundlile.

4. Sebenzisa i-wiring design enengqondo ukuze ubone ukunqanyulwa kokushisa. Ngenxa yokuthi i-resin epulatifeni ine-conductivity ephansi ye-thermal, futhi imigqa ye-foil yethusi nezimbobo ziyi-conductors yokushisa enhle, okwandisa izinga elisele le-foil yethusi nokwandisa izimbobo ezishisayo kuyindlela eyinhloko yokushisa ukushisa.

Ukuze uhlole amandla okukhipha ukushisa kwe-PCB, kuyadingeka ukubala ukuhanjiswa kwe-thermal okulingana (i-eq eyisishiyagalolunye) yezinto eziyinhlanganisela ezakhiwe ngezinto ezihlukene ezine-conductivity ehlukile yokushisa-i-substrate evikelayo ye-PCB.

5. Amadivayisi ebhodini elifanayo eliphrintiwe kufanele ahlelwe ngokusemandleni ngokuhambisana nenani le-calorific kanye nezinga lokuqothula ukushisa. Amadivayisi anevelu ye-calorific ephansi noma ukumelana nokushisa okubi (njengama-transistors wesignali amancane, amasekhethi ahlanganisiwe ezinga elincane, ama-electrolytic capacitor, njll.) kufanele abekwe Ukugeleza okuphezulu kakhulu kokugeleza komoya okupholisa (ekungeneni), kanye namadivayisi anokushisa okukhulu. noma ukumelana nokushisa (njengama-transistors amandla, amasekhethi amakhulu ahlanganisiwe, njll.) abekwe engxenyeni engezansi kakhulu yokugeleza komoya okupholisa.

6. Esiqondisweni esivundlile, amadivaysi anamandla aphezulu ahlelwe eduze ngangokunokwenzeka emaphethelweni ebhodi eliphrintiwe ukuze afinyeze indlela yokudlulisa ukushisa; ohlangothini oluqondile, amadivaysi anamandla aphezulu ahlelwa ngokuseduze ngangokunokwenzeka phezulu kwebhodi eliphrintiwe ukuze kuncishiswe izinga lokushisa kwamanye amadivaysi lapho lezi zisetshenziswa zisebenza. Umthelela.

7. Ukushisa kokushisa kwebhodi eliphrintiwe kumishini ikakhulukazi kuncike ekugelezeni komoya, ngakho-ke indlela yokuhamba komoya kufanele ifundwe ngesikhathi sokuklama, futhi idivayisi noma ibhodi lesifunda eliphrintiwe kufanele lilungiswe ngokufanele.

Lapho umoya ugeleza, uvame ukugeleza ezindaweni ezinokumelana okuphansi, ngakho-ke lapho ulungiselela amadivaysi ebhodini lesifunda eliphrintiwe, gwema ukushiya indawo yomoya enkulu endaweni ethile. Ukumiswa kwamabhodi esekethe aphrintiwe amaningi kuwo wonke umshini kufanele futhi kunake inkinga efanayo.

8. Idivaysi ezwelayo kumazinga okushisa ibekwe kahle endaweni enezinga lokushisa eliphansi kakhulu (njengaphansi kwedivayisi). Ungalokothi uyibeke ngaphezu kwedivayisi yokushisisa. Kungcono ukunyakazisa amadivaysi amaningi endizeni evundlile.

9. Hlela amadivayisi asebenzisa amandla aphezulu kakhulu kanye nesizukulwane sokushisa esiphezulu eduze nendawo engcono kakhulu yokukhipha ukushisa. Ungabeki izinto zokushisisa okuphezulu emakhoneni nasemaphethelweni azungezile ebhodi eliphrintiwe, ngaphandle uma kuhlelwe isinki sokushisa eduze kwayo.

Lapho uklama isivimbeli samandla, khetha idivayisi enkulu ngangokunokwenzeka, futhi uyenze ibe nesikhala esanele sokukhipha ukushisa lapho ulungisa ukwakheka kwebhodi eliphrintiwe.

10. Gwema ukugcwala kwezindawo ezishisayo ku-PCB, sabalalisa amandla ngokulinganayo ebhodini le-PCB ngangokunokwenzeka, futhi ugcine izinga lokushisa elingaphezulu le-PCB lisebenza ngokufanayo futhi lingaguquki.

Ngokuvamile kunzima ukufeza ukusabalalisa okufanayo okuqinile phakathi nenqubo yokuklama, kodwa izindawo ezinamandla amakhulu kakhulu kufanele zigwenywe ukuze kuvinjelwe izindawo ezishisayo ukuthi zingathinti ukusebenza okuvamile kwesifunda sonke.

Uma kunokwenzeka, kuyadingeka ukuhlaziya ukusebenza okushisayo kwesifunda esiphrintiwe. Isibonelo, imojuli yesofthiwe yokuhlaziya inkomba yokusebenza okushisayo engezwe kwenye isofthiwe yedizayini ye-PCB yobungcweti ingasiza abaklami balungiselele idizayini yesekethe.