Lixesha lokuba unike ingqalelo ezinye iinkcukacha ekufumanekeni kwe Ibhodi PCB, Ukulungiselela ngcono ukuqinisekisa umgangatho wemveliso. Xa uzingela ibhodi PCB, kufuneka sinikele ingqalelo kwezi 9 ingqiqo.

1. Akuvunyelwe ngokungqongqo ukusebenzisa izixhobo zovavanyo ezisisiseko ukunxibelelana neTV ebukhoma, iaudiyo, ividiyo kunye nezinye izixhobo ezikwipleyiti esezantsi ukufumana ibhodi yePCB ngaphandle kwesiguquli sodwa.

Sukuvavanya ngokuthe ngqo i-TV, iaudiyo, kunye nezixhobo zevidiyo ngaphandle kwesiguquli sokwahlulahlula amandla nezixhobo ezisisiseko. Nangona ngokubanzi isishicileli sinamandla esiguquli, xa siveliswe ngokukodwa okanye amandla amakhulu okuphuma kwindalo kunikezelo lwamandla abazi kangako ngeTV okanye izixhobo zestereo, qala ucacise ukuba umatshini werhasi uhlawulisiwe, kungenjalo kube lula kakhulu kwaye umgangatho uhlala I-TV, iaudiyo kunye nezinye izixhobo zokuhambisa umbane, zisasazeka kwisekethe edibeneyo, ukonakala okungaphezulu.

2. Nika ingqalelo kwintsebenzo yokugquma yentsimbi ye-soldering iron xa ubhaqa ibhodi ye-PCB

Akuvumelekile ukusebenzisa i-iron soldering ngamandla aphilayo. Ukuqinisekisa ukuba i-iron soldering ayiphili, kungcono ukuba uyicolishe iqokobhe lentsimbi. Isiphaluka se-MOS kufuneka silumke ngakumbi, kwaye sikhuselekile ukusebenzisa isinyithi sevolthi esezantsi ene-6-8V.

3. Ngaphambi kokufumanisa ibhodi ye-PCB, kufuneka siqonde umgaqo osebenzayo wesekethe edibeneyo kunye nesekethe enxulumene nayo

Phambi kokujonga nokulungisa iisekethi ezihlanganisiweyo, kufuneka siqale siqhelane nemisebenzi yeesekethe ezihlanganisiweyo, iisekethe zangaphakathi, iiparameter zombane eziphambili, indima yepini nganye kunye nevolthi eqhelekileyo, ifomathi yamaphini kunye nomgaqo wokusebenza wesekethe eyakhiwe kwipheripherali amacandelo. Ukuba le miqathango ikho, uhlalutyo kunye nokuhlolwa kulula kakhulu.

4, ibhodi yePCB yokuvavanya ayibangeli isekethe emfutshane phakathi kwezikhonkwane

Umlinganiso wevolthi okanye i-oscilloscope probe yovavanyo lwe-waveform, usiba okanye iprosesa ayibangeli isekethe emfutshane phakathi kwezikhonkwane zesekethe ehlanganisiweyo ngenxa yokutyibilika, kungcono ukunxibelelana ngokuthe ngqo nezikhonkwane zesekethe yoshicilelo lomda wokulinganisa. Nawuphi na umjikelo omfutshane okhawulezileyo unokonakalisa ngokulula isekethe ehlanganisiweyo, ke ukhathalelo olongezelelekileyo kufuneka lwenziwe xa kuvavanywa iisekethi ezihlanganisiweyo zeCMOS.

5, detection PCB board test instrument internal resistance should be large

Xa ulinganisa i-voltage ye-DC yezikhonkwane zeesekethe ezihlanganisiweyo, sebenzisa imultimeter enokuxhathisa okungaphakathi kune-20K ω / V; Ngaphandle koko, kuya kubakho iimpazamo ezinkulu zokulinganisa iipesenti ezithile.

6. Nikelani ingqalelo ukusasaza kobushushu besekethe ehlanganisiweyo xa kufunyanwa ibhodi yePCB

Power integrated circuits should have good heat dissipation and should not be allowed to work in a high power state without heat sink.

I-7, ibhodi ye-PCB ekhokelayo ibhaqa kufanelekile

Ukuba kunyanzelekile ukongeza izinto zepheripheripthi ukubuyisela inxenye eyonakeleyo ngaphakathi kwisekethe edityanisiweyo, kufuneka kukhethwe izinto ezincinci, kwaye ii-wiring kufuneka zibe sengqiqweni ukunqanda ukudityaniswa kwe-parasitic, ngakumbi ukujongana nesiphelo somhlaba phakathi kwesandisi sesandi esidityanisiweyo kunye isiphaluka sesampuli.

8. Qinisekisa umgangatho we-welding webhodi ye-PCB

Xa i-welding i-welding ngokwenene, ukuqokelela kwe-solder kunye ne-pores kulula ukudala i-welding ebonakalayo. Ixesha lokuwelda ngokubanzi alikho ngaphezulu kwemizuzwana emi-3, kwaye amandla esinyithi esithengisa malunga ne-25W. Isiphaluka esidityanisiweyo sidityaniswe ngetsimbi ukujonga ngononophelo, kungcono ukusebenzisa i-ohmmeter ukulinganisa ukuba ngaba kukho isekethe emfutshane phakathi kwezikhonkwane, qinisekisa ukuba akukho nto yokubambelela kwi-solder emva koko ucofe umbane.

9, ukufumanisa ibhodi ye-PCB ayikugqibi ngokulula ukonakala kwesekethe ehlanganisiweyo

Do not easily judge that the integrated circuit is damaged. Ngenxa yokuba uninzi lweesekethe ezidityanisiweyo zidityaniswe ngokuthe ngqo, nje ukuba isekethe ayiqhelekanga, inokuthi ikhokelele kutshintsho lweevolthi ezininzi, kwaye olu tshintsho alubangelwa ngumonakalo wesekethe edityanisiweyo, kwaye kwezinye iimeko, ipini yevolthi iyahambelana okanye isondele kwixabiso eliqhelekileyo, isenokungakwazi ukubonisa ukuba isekethe edibeneyo ilungile. Kuba ezinye iimpazamo ezithambileyo azibangeli tshintsho kumbane we-DC.

PCB board debugging method

Ibhodi entsha ye-PCB ibuyisiwe nje, kufuneka kuqala siqwalasele ukuba ngaba kukho iingxaki ebhodini, ezinje ngokuba ngaba kukho iintanda ezicacileyo, nokuba kukho isekethe emfutshane, isekethe evulekileyo kunye nezinye izinto. If necessary, check that the resistance between the power supply and the ground is large enough.

Kwibhodi yesekethe esandula ukuyilwa, ukulungisa ingxaki kuhlala kuhlangana nobunzima, ngakumbi xa ibhodi inkulu, izinto ezingaphezulu, zihlala zingazi ukuba ziqale njani. Kodwa ukuba uyayazi indlela efanelekileyo yokulungisa ingxaki, ukulungisa ingxaki kuya kufumana iziphumo kabini ngesiqingatha somzamo.

Inkqubo yokulungisa iphutha lebhodi ye-PCB

1. For the new PCB board just brought back, we should first roughly observe whether there are problems on the board, such as whether there are obvious cracks, whether there are short circuits, open circuits and other phenomena. If necessary, check that the resistance between the power supply and the ground is large enough.

2, emva koko izinto zokufaka. Iimodyuli ezizimeleyo, ukuba awuqinisekisi ukuba zisebenza ngokufanelekileyo, kungcono ukuba ungazifaki zonke, kodwa yinxalenye yofakelo (kwiisekethi ezincinci ezinokufakwa ngexesha elinye), ukuze kube lula ukufumanisa isiphoso Uluhlu, ukuze xa uhlangabezana neengxaki, ungazi ukuba ungaqala njani.

Generally speaking, you can install the power supply part first, and then check whether the power supply output voltage is normal. Ukuba awuqinisekanga xa ufaka amandla (nokuba ukhona, uyacetyiswa ukuba ungeze i-fuse, kwimeko enokwenzeka), unokucinga ngokusebenzisa umlawuli ombane onokuthi uhlengahlengiswe nomsebenzi okhawulelayo wangoku.

Cwangcisa kuqala ukhuseleko lwangoku, kwaye ixabiso levolthi yolawulo lwamandla kancinci, kwaye ujonge igalelo langoku, umbane wokufaka kunye nevolthi yokuphuma. If no overcurrent protection occurs and the output voltage is normal, the power supply is OK. Ngaphandle koko, nqamula unikezelo lwamandla, fumana isiphoso, kwaye uphinde la manyathelo angentla de umbane uqheleke.

3, emva koko ngokuthe ngcembe ufake ezinye iimodyuli, imodyuli nganye efakiweyo, amandla kuvavanyo, amandla ngokwamanyathelo angentla, ukuthintela ukugqithisa kunye nokutshisa izinto ngenxa yeempazamo zoyilo okanye iimpazamo zokufaka.

Fumana isisombululo sebhodi ye-PCB ephosakeleyo

1. Linganisa umbane ukufumana ibhodi yePCB engalunganga

Into yokuqala yokuqinisekisa ukuba ingaba amandla ombane wepin chip pin aqhelekile na, kwaye ujonge ukuba zonke iintlobo zereferensi yombane ziqhelekile, kwaye nokuba umbane osebenzayo wenqaku ngalinye uqhelekile. Umzekelo oqhelekileyo we-silicon triode, umzekelo, uya kuba ne-voltage ye-junction ye-0.7V kunye ne-CE ye-junction voltage ye-0.3V okanye engaphantsi. Ukuba i-triode ine-voltage ye-junction ye-BE enkulu kune-0.7V (ngaphandle kwee-triode ezikhethekileyo ezinjengeetyhubhu zeDarlington), indawo ekudibana kuyo i-BE inokuthi ivuleke.

2, umqondiso wenaliti yokufumana ibhodi yePCB

Add the signal source to the input end, and then measure the waveform of each point in turn to see whether it is normal to find the fault point. Ngamanye amaxesha siyakusebenzisa indlela elula, enjengokubamba i-tweezer ukuchukumisa i-terminal engenayo kuwo onke amanqanaba ukubona ukuba kukho impendulo kwisiphelo sesiphumo, esihlala sisetyenziswa kwiisekethi zeaudiyo nevidiyo (kodwa kufanele kuqatshelwe ukuba le ndlela ayinakusetyenziswa kwiisekethi ezineepleyiti ezishushu okanye iisekethe ezinamandla aphezulu, kungenjalo inokukhokelela kukothuka kombane). Ukuba akukho mpendulo phambi kwebala, kwaye kukho impendulo emva kwebala, oko kubonisa ukuba ingxaki ikwinqanaba elidlulileyo, kufuneka ijolise kuhlolo.

3. Ezinye iindlela zokufumana iibhodi zePCB eziphosakeleyo

There are many other ways to find trouble spots, such as seeing, hearing, smelling, and touching.

“Jonga” kukujonga ukuba ngaba akukho monakalo uqinisekileyo womatshini kumacandelo, njengokuqhekeka, ukwenza mnyama, deformation, njl.

“Mamela” kukumamela ukuba ingaba isandi somsebenzi siqhelekile na, njengakwezinye izinto akufuneki ziringi, iringi ayikhali okanye isandi asiqhelekanga;

“Vumba” kukujonga ukuba akukho vumba, njengevumba lokutsha, i-capacitor electrolyte incasa, kubasebenzi abanamava bokugcina umbane, kunovakalelo kakhulu kula mavumba;

“Touch” is to use the hand to test whether the temperature of the device is normal, such as too hot, or too cold.

Ezinye izixhobo zamandla, xa zisebenza, zishushu, ukuba kuyabanda ukuya ngaphandle kwebala, ungagweba ukuba ayisebenzi. But if it’s hot where it shouldn’t be or too hot where it should be, that’s no good. General power triode, voltage regulator chip, etc., working in 70 degrees is completely no problem. Ithetha ntoni iidigri ezingama-70? If you can hold your hand on it for more than three seconds, the temperature is probably below 70 degrees (be careful not to burn your hand).