Ubudlelwane phakathi kobubanzi bomkhondo kunye nobubanzi bangoku PCB uyilo

Le yingxaki ebangele ukuba abantu abaninzi baphathwe yintloko. Ndifumene ulwazi kwi-Intanethi ndaza ndalulungisa ngolu hlobo lulandelayo. Kufuneka sazi ukuba ubukhulu befoyile yobhedu yi-0.5oz (malunga ne-18μm), i-1oz (malunga ne-35μm), i-2oz (malunga ne-70μm) yobhedu, i-3oz (malunga ne-105μm) nangaphezulu.

1. Iifom ze-Intanethi

Ixabiso elithwala umthwalo odweliswe kwidatha yetafile yixabiso eliphezulu langoku elinomthwalo kwiqondo lokushisa eliqhelekileyo lama-25 degrees. Ke ngoko, izinto ezahlukeneyo ezinje ngeendawo ezahlukeneyo, iinkqubo zokuvelisa, iinkqubo zeplate, kunye nomgangatho weplate kufuneka ziqwalaselwe kuyilo lokwenyani. Ngoko ke, itheyibhile inikezelwa kuphela njengexabiso lokubhekisela.

2. Umthamo wangoku wokuthwala wefoyile yobhedu enobunzima obahlukeneyo kunye nobubanzi buboniswe kolu luhlu lulandelayo:

Qaphela: Xa usebenzisa ubhedu njenge-conductor ukudlula imisinga emikhulu, umthamo wangoku wokuthwala ububanzi be-foil yobhedu kufuneka uncitshiswe nge-50% ngokubhekiselele kwixabiso kwitheyibhile yokuqwalaselwa kokukhethwa.

3. Ubudlelwane phakathi kobunzima befoyile yobhedu, umkhondo wobubanzi kunye nolwangoku kuyilo lwePCB

Kufuneka ukwazi oko kubizwa ngokuba ukunyuka kweqondo lokushisa: umphumo wangoku wokufudumeza uveliswa emva kokuba umqhubi uqhutywe. Njengoko ixesha lihamba, ubushushu bomphezulu we-conductor buqhubeka bukhuphuka de buzinze. Imeko ezinzileyo kukuba umahluko weqondo lobushushu ngaphambi nangemva kweeyure ezi-3 awudluli kwi-2°C. Ngeli xesha, iqondo lokushisa elilinganisiweyo lomgangatho womqhubi liqondo lokugqibela lomqhubi, kwaye iyunithi yeqondo lokushisa yi-degree (° C). Inxalenye yobushushu obunyukayo obugqitha ubushushu bomoya ojikelezileyo (ubushushu obungqongileyo) ibizwa ngokuba kukunyuka kweqondo lobushushu, kwaye iyunithi yokunyuka kobushushu yiKelvin (K). Kwamanye amanqaku kunye neengxelo zovavanyo kunye nemibuzo yovavanyo malunga nokunyuka kwamaqondo obushushu, iyunithi yokunyuka kweqondo lobushushu ihlala ibhalwa njenge (℃), kwaye ayifanelekanga ukusebenzisa izidanga (℃) ukubonisa ukunyuka kobushushu.

I-PCB substrates idla ngokusetyenziswa FR-4 imathiriyeli. Amandla okubambelela kunye nokushisa okusebenzayo kwe-foil yobhedu kuphezulu kakhulu. Ngokuqhelekileyo, ubushushu obuvumelekileyo be-PCB yi-260℃, kodwa iqondo lokwenene le-PCB akufanele lidlule i-150℃, kuba ukuba lidlula eli bushushu Lisondele kakhulu kwindawo yokunyibilika kwe-solder (183 ° C). Ngexesha elifanayo, ukushisa okuvumelekileyo kwamacandelo ebhodi kufuneka kuthathelwe ingqalelo. Ngokuqhelekileyo, ii-IC zodidi lwabemi zinokumelana kuphela nobukhulu obungu-70°C, ii-ICs zodidi lwe-industrial ngu-85°C, yaye ii-IC zodidi lomkhosi zinokumelana kuphela nobuninzi be-125°C. Ke ngoko, iqondo lobushushu lefoyile yobhedu kufutshane ne-IC kwi-PCB ene-ICs yoluntu kufuneka ilawulwe kwinqanaba elisezantsi. Kuphela zizixhobo zamandla aphezulu ezinokumelana nobushushu obuphezulu (125℃～175℃) ezinokuvunyelwa ukuba zibe phezulu. Ubushushu be-PCB, kodwa isiphumo sobushushu obuphezulu be-PCB ekuchitheni ubushushu bezixhobo zamandla nazo kufuneka ziqwalaselwe.