Kwizixhobo ze-elektroniki, umlinganiselo othile wokushisa uveliswa ngexesha lokusebenza, ukwenzela ukuba ukushisa kwangaphakathi kwezixhobo kukhuphuke ngokukhawuleza. Ukuba ubushushu abuchithwanga ngexesha, izixhobo ziya kuqhubeka zifudumala, kwaye isixhobo siya kusilela ngenxa yokushisa. Ukuthembeka kwezixhobo ze-elektroniki Ukusebenza kuya kuncipha.

Ngoko ke, kubaluleke kakhulu ukuqhuba unyango olufanelekileyo lokutshatyalaliswa kobushushu kwi- ibhodi yesekethe. Ukutshatyalaliswa kobushushu bebhodi yesekethe ye-PCB likhonkco elibaluleke kakhulu, ngoko yintoni ubuchule bokutshatyalaliswa kobushushu bebhodi yesekethe ye-PCB, makhe siyixoxe kunye ngezantsi.

1. Ukutshatyalaliswa kobushushu ngebhodi ye-PCB ngokwayo Iibhodi ze-PCB ezisetyenziswa ngoku ngokubanzi zi-copper clad/epoxy glass cloth substrates okanye i-phenolic resin glass cloth substrates, kunye nenani elincinci leebhodi zobhedu ezisekelwe ephepheni ziyasetyenziswa.

Nangona ezi substrates zineempawu ezigqwesileyo zombane kunye nepropathi yokusetyenzwa, zinokuphelisa ubushushu. Njengomzila wokutshatyalaliswa kobushushu kumacandelo aphezulu okufudumeza, phantse akunakwenzeka ukulindela ukushisa kwi-resin ye-PCB ngokwayo ukuqhuba ubushushu, kodwa ukutshabalalisa ubushushu ukusuka kumphezulu wecandelo ukuya kumoya ojikelezayo.

Nangona kunjalo, njengoko iimveliso ze-elektroniki ziye zangena kwixesha le-miniaturization yamacandelo, ukunyuka kwe-high-density mounting, kunye ne-high-heating assembly, akwanelanga ukuthembela kumphezulu wecandelo elinommandla omncinci kakhulu wokulahla ukushisa.

Ngelo xesha, ngenxa yokusetyenziswa ngokubanzi kwezixhobo zokunyuka kwendawo ezifana ne-QFP kunye ne-BGA, ubushushu obuveliswa ngamacandelo budluliselwa kwibhodi ye-PCB kwisixa esikhulu. Ngoko ke, eyona ndlela ilungileyo yokusombulula ukutshatyalaliswa kobushushu kukuphucula amandla okutshatyalaliswa kobushushu bePCB ngokwayo edibana ngokuthe ngqo nento yokufudumeza. Iza kusasazwa okanye ikhutshwe.

Yongeza i-foil yethusi ekhupha ukushisa kunye ne-copper foil kunye nokunikezelwa kwamandla ommandla omkhulu

Thermal nge

Ukuvezwa kobhedu ngasemva kwe-IC kunciphisa ukuxhathisa kwe-thermal phakathi kwesikhumba sobhedu kunye nomoya.

Uyilo lwePCB

a. Beka isixhobo esibuthathaka kubushushu kwindawo yomoya obandayo.

b. Beka isixhobo sokubona ubushushu kweyona ndawo ishushu.

c. Izixhobo ezikwibhodi enye eprintiweyo kufuneka zicwangciswe ngokusemandleni ngokwexabiso labo le-calorific kunye neqondo lokutshatyalaliswa kobushushu. Izixhobo ezinexabiso eliphantsi lecalorific okanye ukunganyangeki kobushushu (ezifana neetransistors zomqondiso omncinci, iisekethe ezihlanganisiweyo ezincinci, i-electrolytic capacitors, njl.njl.) kufuneka zibekwe Ukuhamba okuphezulu kokuhamba komoya okupholisa (ekungeneni), kunye nezixhobo ezinobushushu obukhulu. ukuveliswa okanye ukumelana nobushushu obuhle (njengama-transistors amandla, iisekethe ezinkulu ezidibeneyo, njl. njl.) zibekwe kwindawo esezantsi yokupholisa umoya.

d. Kwicala elithe tye, izixhobo eziphezulu zamandla zibekwe ngokusondeleyo kumda webhodi eprintiweyo ngokusemandleni ukunciphisa indlela yokudlulisa ukushisa; kwicala elithe nkqo, izixhobo eziphezulu zamandla zibekwe ngokusondeleyo kumphezulu webhodi eprintiweyo ngokusemandleni ukunciphisa ubushushu bezinye izixhobo xa ezi zixhobo zisebenza Impembelelo.

e. Ukutshatyalaliswa kobushushu bebhodi eprintiweyo kwisixhobo ikakhulu kuxhomekeke ekuhambeni komoya, ngoko ke indlela yokuhamba komoya kufuneka ifundwe ngexesha loyilo, kwaye isixhobo okanye ibhodi yesekethe eprintiweyo kufuneka iqwalaselwe ngokufanelekileyo. Xa umoya uhamba, uhlala uhamba kwiindawo ezinokuxhatshazwa okuphantsi, ngoko xa ulungiselela izixhobo kwibhodi yesekethe eprintiweyo, gwema ukushiya indawo enkulu yomoya kwindawo ethile. Ukucwangciswa kweebhodi zeesekethe ezininzi eziprintiweyo kuwo wonke umatshini kufuneka kwakhona ingqalelo ingxaki efanayo.

f. Isixhobo esingevayo kubushushu sibekwe kakuhle kweyona ndawo isezantsi yobushushu (njengamazantsi esixhobo). Ungaze uyibeke ngqo phezu kwesixhobo sokufudumeza. Kungcono ukugxadazela izixhobo ezininzi kwinqwelomoya ethe tye.

g. Lungiselela izixhobo ezinosetyenziso lwamandla aphezulu kunye neyona mveliso yobushushu iphezulu kufutshane neyona ndawo ilungileyo yokuphelisa ubushushu. Musa ukubeka izixhobo zokufudumeza okuphezulu kwiikona kunye nemida ye-peripheral yebhodi eprintiweyo, ngaphandle kokuba i-heat sink ilungiselelwe kufuphi nayo. Xa uyila i-resistor yamandla, khetha isixhobo esikhulu kangangoko kunokwenzeka, kwaye usenze sibe nesithuba esaneleyo sokutshatyalaliswa kobushushu xa uhlengahlengisa ukwakheka kwebhodi eprintiweyo.

h. Isithuba secandelo elicetyisiweyo:

Iindlela ezili-10 ezisebenzayo zokuphelisa ubushushu kwiPCB

Iindlela ezili-10 ezisebenzayo zokuphelisa ubushushu kwiPCB

2. Amacandelo aphezulu avelisa ubushushu kunye neeradiyetha kunye neepleyiti zokuqhuba ubushushu. Xa amacandelo ambalwa kwi-PCB evelisa inani elikhulu lobushushu (ngaphantsi kwe-3), i-heat sink okanye umbhobho wokushisa unokongezwa kwizinto ezivelisa ukushisa. Xa iqondo lobushushu lingenakwehliswa, Iradiyetha enefeni ingasetyenziselwa ukomeleza ifuthe lokuphelisa ubushushu.

Xa inani lezixhobo zokufudumeza likhulu (ngaphezu kwe-3), isigqubuthelo esikhulu sokutshatyalaliswa kobushushu (ibhodi) singasetyenziswa, esisitshi esikhethekileyo sokushisa esilungiselelwe ngokwendawo kunye nokuphakama kwesixhobo sokufudumeza kwi-PCB okanye i-flat enkulu. isinki yobushushu Sika iindawo ezahlukeneyo zobude becandelo.

Isigqubuthelo sokutshatyalaliswa kobushushu sihlanganiswe ngokudibeneyo kumphezulu wecandelo, kwaye sidibanisa necandelo ngalinye ukutshabalalisa ubushushu. Nangona kunjalo, umphumo wokutshatyalaliswa kobushushu awulungile ngenxa yokungahambi kakuhle kokuphakama ngexesha lokudibanisa kunye ne-welding yamacandelo. Ngokuqhelekileyo, isigaba esithambileyo sokutshintsha i-thermal pad yongezwa kumphezulu wecandelo ukuphucula umphumo wokutshatyalaliswa kobushushu.

3. Kwizixhobo ezithatha ukupholisa umoya we-convection wamahhala, kungcono ukulungiselela iisekethe ezidibeneyo (okanye ezinye izixhobo) ngokuthe ngqo okanye ngokuthe tye.

4. Sebenzisa uyilo locingo olufanelekileyo ukuqonda ukutshatyalaliswa kobushushu. Ngenxa yokuba i-resin kwipleyiti ine-conductivity ephantsi ye-thermal, kunye nemigca yefoyile yobhedu kunye nemingxuma yi-conductors yokushisa efanelekileyo, ukwandisa izinga eliseleyo le-foil yobhedu kunye nokwandisa imingxuma ye-thermal yeyona ndlela iphambili yokutshatyalaliswa kobushushu.

Ukuvavanya amandla okutshatyalaliswa kobushushu bePCB, kuyimfuneko ukubala ukuhanjiswa kwe-thermal elinganayo (i-eq elithoba) yezinto ezidibeneyo ezenziwe ngezinto ezahlukeneyo ezine-conductivity ye-thermal-i-insulating substrate ye-PCB.

5. Izixhobo ezikwibhodi eprintiweyo efanayo kufuneka zicwangciswe ngokusemandleni ngokwexabiso le-calorific kunye neqondo lokutshatyalaliswa kobushushu. Izixhobo ezinexabiso eliphantsi lecalorific okanye ukunganyangeki kobushushu (ezifana neetransistors zomqondiso omncinci, iisekethe ezihlanganisiweyo ezincinci, i-electrolytic capacitors, njl.njl.) kufuneka zibekwe Ukuhamba okuphezulu kokuhamba komoya okupholisa (ekungeneni), kunye nezixhobo ezinobushushu obukhulu. okanye ukumelana nobushushu (njengama-transistors amandla, iisekethe ezinkulu ezidibeneyo, njl.njl.) zibekwe kwindawo esezantsi ye-airflow yokupholisa.

6. Kwicala elithe tye, izixhobo eziphezulu zamandla zilungiselelwe ngokusondeleyo kumda webhodi eprintiweyo ukunciphisa umzila wokushisa ukushisa; kwicala elithe nkqo, izixhobo eziphezulu zamandla zicwangciswe ngokusondeleyo kangangoko kunokwenzeka kumphezulu webhodi eprintiweyo ukunciphisa ubushushu bezinye izixhobo xa ezi zixhobo zisebenza. Impembelelo.

7. Ukutshatyalaliswa kokushisa kwebhodi eprintiweyo kwisixhobo ngokuyinhloko kuxhomekeke ekuhambeni komoya, ngoko ke indlela yokuhamba komoya kufuneka ifundwe ngexesha loyilo, kwaye isixhobo okanye ibhodi yesekethe eprintiweyo kufuneka iqulunqwe ngokufanelekileyo.

Xa umoya uhamba, uhlala uhamba kwiindawo ezinokuxhatshazwa okuphantsi, ngoko xa ulungiselela izixhobo kwibhodi yesekethe eprintiweyo, gwema ukushiya indawo enkulu yomoya kwindawo ethile. Ukucwangciswa kweebhodi zeesekethe ezininzi eziprintiweyo kuwo wonke umatshini kufuneka kwakhona ingqalelo ingxaki efanayo.

8. Isixhobo esingevayo kubushushu sibekwe kakuhle kweyona ndawo isezantsi yobushushu (njengamazantsi esixhobo). Ungaze uyibeke ngqo phezu kwesixhobo sokufudumeza. Kungcono ukugxadazela izixhobo ezininzi kwinqwelomoya ethe tye.

9. Lungiselela izixhobo ngeyona ndlela iphezulu yokusebenzisa amandla kunye neyona mveliso yobushushu iphezulu kufutshane neyona ndawo ilungileyo yokulahla ubushushu. Musa ukubeka izixhobo zokufudumeza okuphezulu kwiikona kunye nemida ye-peripheral yebhodi eprintiweyo, ngaphandle kokuba i-heat sink ilungiselelwe kufuphi nayo.

Xa uyila i-resistor yamandla, khetha isixhobo esikhulu kangangoko kunokwenzeka, kwaye usenze sibe nesithuba esaneleyo sokutshatyalaliswa kobushushu xa uhlengahlengisa ukwakheka kwebhodi eprintiweyo.

10. Kuphephe ukuxinana kweendawo ezishushu kwi-PCB, usasaze amandla ngokulinganayo kwibhodi ye-PCB kangangoko kunokwenzeka, kwaye ugcine i-PCB yomphezulu wobushushu bokusebenza iyunifomu kwaye ihambelana.

Ngokuqhelekileyo kunzima ukufezekisa ukusabalalisa okufanayo ngokungqongqo ngexesha lenkqubo yokuyila, kodwa iindawo ezinobunzima obukhulu kakhulu kufuneka zigwenywe ukukhusela iindawo ezishushu ezichaphazela ukusebenza okuqhelekileyo kwesekethe yonke.

Ukuba kunokwenzeka, kuyimfuneko ukuhlalutya ukusebenza kwe-thermal yesekethe eprintiweyo. Umzekelo, imodyuli yohlalutyo lwesalathiso sokusebenza kwe-thermal eyongezwe kwisoftware yoyilo lwePCB yobuchwephesha inokunceda abaqulunqi baphucule uyilo lwesekethe.