O to akoko lati san ifojusi si awọn alaye diẹ ninu iṣawari ti PCB ọkọ, nitorinaa lati mura silẹ dara julọ lati rii daju didara ọja. Nigbati o ba n rii igbimọ PCB, o yẹ ki a fiyesi si oye ti o wọpọ 9 wọnyi.

1. O jẹ eewọ muna lati lo ohun elo idanwo ilẹ lati kan si TV laaye, ohun, fidio ati ohun elo miiran lori awo isalẹ lati rii igbimọ PCB laisi oluyipada ipinya.

Maṣe ṣe idanwo TV taara, ohun, ati awọn ẹrọ fidio laisi awọn oluyipada ipinya agbara pẹlu awọn ẹrọ ilẹ. Botilẹjẹpe gbogbogbogbo agbohunsilẹ ni oluyipada agbara, nigbati o ba farahan si pataki pataki kan tabi agbara iṣelọpọ nla ti iseda ti ipese agbara ko mọ pupọ nipa TV tabi ohun elo sitẹrio, kọkọ jẹ ki o han gbangba pe ẹnjini ẹrọ ti gba agbara, bibẹẹkọ rọrun pupọ ati igbesi aye ilẹ. TV, ohun ati Circuit ipese agbara ohun elo miiran, tan kaakiri iṣọpọ, awọn fifọ siwaju.

2. San ifojusi si iṣẹ idabobo ti iron soldering iron nigba wiwa PCB ọkọ

A ko gba ọ laaye lati lo iron soldering pẹlu agbara laaye. Lati rii daju pe irin tita ko wa laaye, o dara julọ lati kọ ikarahun ti irin ta. Circuit MOS yẹ ki o ṣọra diẹ sii, ati pe o jẹ ailewu lati lo irin Circuit-kekere pẹlu 6-8V.

3. Ṣaaju ki o to rii PCB ọkọ, o yẹ ki a loye ilana iṣiṣẹ ti Circuit iṣọpọ ati Circuit ti o ni ibatan

Ṣaaju ki o to ṣayẹwo ati tunṣe awọn iyika iṣọpọ, o yẹ ki a kọkọ faramọ pẹlu awọn iṣẹ ti awọn iyika iṣọpọ, awọn iyika inu, awọn iwọn itanna akọkọ, ipa ti PIN kọọkan ati foliteji deede, igbi ti pin ati ilana iṣẹ ti Circuit ti o jẹ agbeegbe irinše. Ti awọn ipo wọnyi ba wa, itupalẹ ati ayewo rọrun pupọ.

4, igbimọ PCB idanwo ko fa Circuit kukuru laarin awọn pinni

Iwọn wiwọn foliteji tabi igbi idanwo idanwo oscilloscope, pen tabi iwadii ko fa Circuit kukuru laarin awọn pinni ti Circuit iṣọpọ nitori sisun, o dara julọ lati ni asopọ taara pẹlu awọn pinni ti agbegbe titẹ sita agbeegbe fun wiwọn. Eyikeyi Circuit kukuru eyikeyi le ṣe rọọrun ba Circuit INTEGRATED jẹ, nitorinaa o yẹ ki o gba itọju diẹ sii nigba idanwo awọn iyipo iṣọpọ CMOS alapin.

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

Nigbati o ba ṣe iwọn wiwọn DC ti awọn pinni ti awọn iyika iṣọpọ, lo multimeter kan ti resistance inu rẹ tobi ju 20K ω /V; bibẹẹkọ, awọn aṣiṣe wiwọn nla yoo wa fun diẹ ninu awọn folti pin.

6. San ifojusi si igbona ooru ti Circuit ese agbara nigbati o rii igbimọ PCB

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

7, erin oludari PCB yẹ ki o jẹ ironu

Ti o ba jẹ dandan lati ṣafikun awọn paati agbegbe lati rọpo apakan ti o bajẹ ninu Circuit iṣọpọ, o yẹ ki o yan awọn paati kekere, ati wiwọn yẹ ki o jẹ ironu lati yago fun idapọ parasitic ti ko wulo, ni pataki lati wo pẹlu opin ilẹ laarin ohun afetigbọ ohun afetigbọ ese ati Circuit preamplifier.

8. Rii daju didara alurinmorin ti igbimọ PCB

Nigba ti alurinmorin ti wa ni gan welded, ikojọpọ ti solder ati pores ni o rọrun lati fa foju alurinmorin. Akoko alurinmorin kii ṣe diẹ sii ju awọn aaya 3 lọ, ati agbara ti iron iron jẹ nipa 25W. Circuit ti a ti papọ ti ni alurinmorin lati ṣayẹwo ni pẹkipẹki, o dara julọ lati lo ohmmeter lati wiwọn boya Circuit kukuru wa laarin awọn pinni, jẹrisi ko si isomọ adhesion solder lẹhinna yipada lori ipese agbara.

9, wiwa ti igbimọ PCB ko ni rọọrun pinnu ibajẹ ti Circuit ti a ṣepọ

Do not easily judge that the integrated circuit is damaged. Nitori opo pupọ ti awọn iyika iṣọpọ ni idapo taara, ni kete ti Circuit kan jẹ ohun ajeji, o le ja si awọn ayipada foliteji lọpọlọpọ, ati pe awọn ayipada wọnyi ko jẹ dandan fa nipasẹ ibajẹ ti Circuit iṣọpọ, ati ni awọn igba miiran, wiwọn pin pin jẹ ni ibamu pẹlu tabi sunmọ iye deede, o le ma ni anfani lati fihan pe Circuit iṣọpọ dara. Nitori diẹ ninu awọn abawọn rirọ ko fa awọn ayipada ninu folti DC.

PCB board debugging method

Fun igbimọ PCB tuntun ti o kan mu pada, o yẹ ki a kọkọ wo ni aijọju boya awọn iṣoro wa lori igbimọ, bii boya awọn dojuijako ti o han, boya Circuit kukuru wa, Circuit ṣiṣi ati awọn iyalẹnu miiran. If necessary, check that the resistance between the power supply and the ground is large enough.

Fun igbimọ Circuit tuntun ti a ṣe apẹrẹ, n ṣatunṣe aṣiṣe nigbagbogbo ba pade diẹ ninu awọn iṣoro, ni pataki nigbati igbimọ ba tobi, awọn paati diẹ sii, nigbagbogbo ko mọ bi o ṣe le bẹrẹ. Ṣugbọn ti o ba ṣakoso ọna imukuro ti o peye, n ṣatunṣe aṣiṣe yoo gba abajade lẹẹmeji pẹlu idaji igbiyanju naa.

Ilana n ṣatunṣe aṣiṣe 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, ati lẹhinna awọn paati fifi sori ẹrọ. Awọn modulu olominira, ti o ko ba rii daju pe wọn ṣiṣẹ daradara, o dara julọ lati ma fi gbogbo wọn sori ẹrọ, ṣugbọn apakan ti fifi sori ẹrọ (fun awọn iyika kekere, le fi sii ni ẹẹkan), ki o rọrun lati pinnu aṣiṣe naa ibiti, nitorinaa nigbati o ba pade awọn iṣoro, ko mọ bi o ṣe le bẹrẹ.

Generally speaking, you can install the power supply part first, and then check whether the power supply output voltage is normal. Ti o ko ba ni idaniloju pupọ nigbati o ba n tan agbara (paapaa ti o ba wa, o gba ọ niyanju lati ṣafikun fiusi kan, ni ọran), o le ronu nipa lilo oluṣakoso foliteji adijositabulu pẹlu iṣẹ diwọn lọwọlọwọ.

Ni akọkọ tito aabo lọwọlọwọ, ati lẹhinna iye foliteji ti ipese agbara eleto laiyara soke, ati ṣe atẹle lọwọlọwọ titẹsi, folti titẹ sii ati folti o wujade. If no overcurrent protection occurs and the output voltage is normal, the power supply is OK. Bibẹẹkọ, ge asopọ ipese agbara, wa ẹbi, ati tun awọn igbesẹ ti o wa loke ṣe titi ipese agbara yoo jẹ deede.

3, lẹhinna fi sori ẹrọ awọn modulu diẹdiẹ, modulu kọọkan ti fi sii, agbara lori idanwo, agbara lori ni ibamu si awọn igbesẹ ti o wa loke, lati le yago fun apọju ati sisun awọn paati nitori awọn aṣiṣe apẹrẹ tabi awọn aṣiṣe fifi sori ẹrọ.

Wa awọn ojutu ti mẹhẹ PCB ọkọ

1. Ṣe iwọn foliteji lati wa igbimọ PCB ti ko tọ

The first thing to confirm is whether the voltage of the chip power pin is normal, and then check whether all kinds of reference voltage is normal, and whether the working voltage of each point is normal. Triode silikoni aṣoju, fun apẹẹrẹ, yoo ni foliteji idapọmọra BE ti o wa ni ayika 0.7V ati foliteji idapọmọra CE ti o wa ni ayika 0.3V tabi kere si. Ti o ba jẹ pe mẹta kan ni foliteji idapọmọra BE ti o tobi ju 0.7V (ayafi fun awọn mẹta pataki bii awọn tubes Darlington), isọdọkan BE le ṣii.

2, ọna abẹrẹ ifihan lati wa ẹbi PCB ẹbi

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. Nigba miiran a yoo tun lo ọna ti o rọrun, gẹgẹ bi didimu tweezer lati fi ọwọ kan ebute iwọle ni gbogbo awọn ipele lati rii boya iṣesi wa ni ebute iṣeejade, eyiti a lo nigbagbogbo ni ohun ati awọn iyika ampilifaya fidio (ṣugbọn o yẹ ki o ṣe akiyesi pe ọna yii ko le ṣee lo ni awọn iyika pẹlu awọn awo ipilẹ to gbona tabi awọn iyika foliteji giga, bibẹẹkọ o le ja si mọnamọna ina). Ti ko ba si ifura ṣaaju ifọwọkan, ati pe ifura kan wa lẹhin ifọwọkan, o fihan pe iṣoro naa wa ni ipele ti tẹlẹ, yẹ ki o dojukọ ayewo.

3. Awọn ọna miiran fun wiwa awọn lọọgan PCB ti ko tọ

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

“Wo” ni lati rii boya ibajẹ ẹrọ ti o han gbangba si awọn paati, gẹgẹ bi rupture, didaku, idibajẹ, ati bẹbẹ lọ;

“Gbọ” ni lati tẹtisi boya ohun iṣẹ jẹ deede, gẹgẹ bi awọn ohun kan ko yẹ ki o dun ni iwọn, oruka ko dun tabi ohun naa ko ṣe deede;

“Olfato” ni lati ṣayẹwo boya olfato wa, gẹgẹ bi olfato ti sisun, itọwo elekitiro eleto, fun oṣiṣẹ itọju itanna ti o ni iriri, ni itara pupọ si awọn oorun wọnyi;

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

Diẹ ninu awọn ẹrọ agbara, nigbati o ba n ṣiṣẹ, igbona, ti o ba tutu si ifọwọkan, o le ṣe idajọ ni ipilẹ pe ko ṣiṣẹ. 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. Kini iwọn 70 tumọ si? 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).