Nine umqondo ovamile PCB ukuhlolwa

1. Akuvunyelwe ngokuphelele ukusebenzisa imishini yokuhlola esekelwe phansi ukuze uthinte i-TV ebukhoma, umsindo, ividiyo nezinye izisetshenziswa zepuleti elingezansi ukuze uhlole ibhodi le-PCB ngaphandle kwesiguquli sokuhlukanisa.

Kwenqatshelwe ngokuphelele ukuhlola ngokuqondile i-TV, umsindo, ividiyo nezinye izinto zokusebenza ngaphandle kwesiguquli sokuhlukanisa amandla esinamathuluzi nezinto zokusebenza ezinezivikelo ezisekelwe phansi.

Nakuba isiqophamazwi sekhasethi yomsakazo jikelele sine-transformer yamandla, lapho uhlangana ne-TV ekhethekile noma imishini yokulalelwayo, ikakhulukazi amandla aphumayo noma uhlobo lwamandla asetshenziswayo, kufanele uqale uthole ukuthi i-chassis yomshini ishajiwe yini. , ngaphandle kwalokho kuzoba lula kakhulu I-TV, i-audio kanye nezinye izinto zokusebenza ezikhokhiswa nge-backplane kubangela isifunda esifushane sokunikezwa kwamandla, okuthinta isifunda esihlanganisiwe, okubangela ukwanda okuqhubekayo kwephutha.

2. Naka ukusebenza kokufakwa kwensimbi kagesi lapho uhlola ibhodi le-PCB

Akuvunyelwe ukusebenzisa i-solder iron for soldering ngamandla. Qinisekisa ukuthi i-soldering iron ayikhokhiswa. Kungcono ukugaya igobolondo le-soldering iron. Qaphela kakhulu ngesekhethi ye-MOS. Kuphephe kakhudlwana ukusebenzisa insimbi ene-voltage ephansi ye-soldering engu-6 ~ 8V.

3. Ngaphambi kokuhlola ibhodi le-PCB, qonda isimiso sokusebenza samasekhethi ahlanganisiwe namasekhethi ahlobene

Ngaphambi kokuhlola nokulungisa isekethe ehlanganisiwe, kufanele uqale wazi umsebenzi wesekethe ehlanganisiwe esetshenzisiwe, isifunda sangaphakathi, imingcele eyinhloko kagesi, indima yephini ngalinye, kanye ne-voltage evamile yephini, i-waveform kanye nokusebenza. isimiso sesekhethi esakhiwe izingxenye ze-peripheral.

Uma izimo ezingenhla zihlangene, ukuhlaziya nokuhlola kuzoba lula kakhulu.

4. Ungabangeli ukujikeleza okufushane phakathi kwamaphini lapho uhlola ibhodi le-PCB

Lapho ukala i-voltage noma uhlola i-waveform nge-oscilloscope probe, ungabangeli ukujikeleza okufushane phakathi kwamaphini wesekethe ehlanganisiwe ngenxa yokuslayida kwemikhondo yokuhlola noma ama-probe. Kungcono ukulinganisa kumjikelezo ophrintiwe we-peripheral oxhunywe ngqo nezikhonkwane.

Noma iyiphi isekethe yesikhashana ingalimaza kalula isekethe edidiyelwe. Kufanele uqaphele kakhulu lapho uhlola amasekhethi ahlanganisiwe e-CMOS anephakheji eliyisicaba.

5. Ukumelana kwangaphakathi kwethuluzi lokuhlola ibhodi le-PCB kufanele kube kukhulu

Lapho kulinganiswa i-voltage ye-DC yezikhonkwane ze-IC, i-multimeter enokumelana kwangaphakathi kwekhanda lemitha elikhulu kuno-20KΩ/V kufanele isetshenziswe, ngaphandle kwalokho kuzoba nephutha elikhulu lokulinganisa le-voltage yamanye amaphini.

6. Naka ukuchithwa kokushisa kwesekethe ehlanganisiwe yamandla lapho uthola ibhodi le-PCB

Isifunda esihlanganisiwe samandla kufanele sibe nokushisa okuhle kokushisa, futhi akuvunyelwe ukusebenza esimweni samandla aphezulu ngaphandle kokushisa kokushisa.

7. Intambo eholayo yebhodi le-PCB kufanele ihlolwe ngokufanele

Uma udinga ukwengeza izingxenye zangaphandle esikhundleni sezingxenye ezilimele zesekethe edidiyelwe, izingxenye ezincane kufanele zikhethwe, futhi izintambo kufanele zibe nengqondo ukuze ugweme ukuhlangana kwe-parasitic okungadingekile, ikakhulukazi ukumisa phansi phakathi kwesekethe ehlanganisiwe ye-audio amplifier kanye nokuphela kwesekhethi yangaphambili. .

8. Ukuhlola ibhodi le-PCB ukuqinisekisa ikhwalithi yokushisela

Lapho i-soldering, i-solder iqinile, futhi ukuqoqwa kwe-solder nama-pores kungenzeka kubangele ukuthungatha okungamanga. Isikhathi se-soldering ngokuvamile asidluli imizuzwana engu-3, ​​futhi amandla ensimbi e-solder kufanele abe ngu-25W ngokufudumeza kwangaphakathi.

Isifunda esihlanganisiwe esidayisiwe kufanele sihlolwe ngokucophelela. Kungcono ukusebenzisa i-ohmmeter ukukala ukuthi kukhona isifunda esifushane phakathi kwezikhonkwane, uqinisekise ukuthi akukho ukunamathela kwe-solder, bese uvula amandla.

9. Ungatholi kalula umonakalo wesekethe ehlanganisiwe lapho uhlola ibhodi le-PCB

Ungahluleli ukuthi isifunda esihlanganisiwe sonakaliswa kalula. Ngenxa yokuthi iningi lamasekhethi ahlanganisiwe ahlanganiswe ngokuqondile, uma isekethe ingajwayelekile, ingase ibangele izinguquko eziningi zamandla kagesi, futhi lezi zinguquko azibangelwa ngempela ukulimala kwesekethe ehlanganisiwe.

Ngaphezu kwalokho, kwezinye izimo, lapho i-voltage elinganisiwe yephini ngalinye ifana noma iseduze nenani elivamile, ingase ingabonisi ngaso sonke isikhathi ukuthi isifunda esihlanganisiwe silungile. Ngoba inkundla ye-elekthronikhi ye-EDA365 ithole ukuthi amanye amaphutha athambile ngeke abangele izinguquko ku-voltage ye-DC.

Indlela yokulungisa iphutha yebhodi le-PCB

Ebhodini elisha le-PCB elisanda kubuyiselwa, i-EDA365 Electronics Forum incoma ukuthi uqale ubheke ukuthi zikhona yini izinkinga ebhodini, njengokuthi kukhona yini ukuqhekeka okusobala, amasekhethi amafushane, amasekhethi avuliwe, njll. Uma kunesidingo, hlola ukuthi ukumelana phakathi kokunikezwa kwamandla kanye nentambo yaphansi kukhulu ngokwanele.

Ebhodini lesifunda elisanda kwakhiwa, ukulungisa iphutha kuvame ukubhekana nobunzima obuthile, ikakhulukazi lapho ibhodi likhulu futhi kunezingxenye eziningi, ngokuvamile akunakwenzeka ukuqala. Kodwa uma wazi isethi yezindlela zokulungisa iphutha, ukulungisa iphutha kuzothola umphumela ophindwe kabili ngomzamo oyingxenye.

Izinyathelo zokulungisa iphutha lebhodi le-PCB:

1. Ebhodini elisha le-PCB elisanda kubuyiselwa, kufanele siqale sibheke ukuthi azikho yini izinkinga ebhodini, njengokuthi kukhona yini ukuqhekeka okusobala, amasekhethi amafushane, amasekhethi avuliwe, njll. Uma kunesidingo, hlola ukuthi ukumelana phakathi kokunikezwa kwamandla kanye nentambo yaphansi kukhulu ngokwanele.

2. Bese kufakwa izingxenye. Amamojula azimele, uma ungaqiniseki ukuthi asebenza kahle, kungcono ukuthi ungawafaki wonke, kodwa ukufaka ingxenye ngengxenye (ama-circuits amancane, ungawafaka ngesikhathi esisodwa), ukuze kube lula. ukunquma ububanzi bephutha. Gwema ukuba nenkinga ukuqalisa lapho uhlangabezana nezinkinga.

Ngokuvamile, ungafaka ugesi kuqala, bese uvula ukuze uhlole ukuthi i-voltage ephumayo yomthombo wamandla ijwayelekile yini. Uma ungenakho ukuzethemba okukhulu lapho unika amandla (ngisho noma uqinisekile, kuyanconywa ukuthi wengeze i-fuse, uma kwenzeka), cabanga ukusebenzisa ukunikezwa kwamandla okulawulwayo okulawulwayo okunomsebenzi wamanje wokukhawulela.

Misa kusengaphambili i-current yamanje yokuvikela kuqala, bese ukhuphula kancane kancane inani le-voltage yokuphakelwa kwamandla okulawulwayo, futhi uqaphe amandla okokufaka, i-voltage yokufaka, ne-voltage ephumayo. Uma kungekho ukuvikelwa kwe-overcurrent nezinye izinkinga ngesikhathi sokulungiswa okuphezulu, futhi i-voltage yokuphuma isifinyelele evamile, ukunikezwa kwamandla KULUNGILE. Uma kungenjalo, nqamula ukunikezwa kwamandla, thola iphuzu lephutha, bese uphinda izinyathelo ezingenhla kuze kube yilapho ukunikezwa kwamandla sekujwayelekile.

3. Okulandelayo, faka amanye amamojula kancane kancane. Ngemva kokufakwa kwemojuli ngayinye, vula futhi uyihlole. Uma ukhanyisa, landela lezi zinyathelo ezingenhla ukuze ugweme ukudlulela manje futhi ushise izingxenye ngenxa yamaphutha edizayini noma/namaphutha okufaka.

Finding the method of PCB board failure

1. Thola ibhodi le-PCB elinephutha ngokulinganisa indlela kagesi

Into yokuqala okufanele uqinisekise ukuthi i-voltage yamaphini wokuphakela amandla we-chip ngayinye ijwayelekile, bese uhlola ukuthi ama-voltages ahlukene ayizethenjwa ajwayelekile yini. Ngaphezu kwalokho, iforamu ye-elektroniki ye-EDA365 ikhumbuza: futhi uqinisekise ukuthi i-voltage yokusebenza yephuzu ngalinye ijwayelekile, njll.

Isibonelo, lapho i-silicon transistor evamile ivuliwe, i-BE junction voltage icishe ibe ngu-0.7V, kuyilapho i-CE junction voltage icishe ibe ngu-0.3V noma ngaphansi. Uma i-BE junction voltage ye-transistor inkulu kuno-0.7V (ngaphandle kwama-transistors akhethekile, afana ne-Darlington, njll.), kungenzeka ukuthi i-BE junction ivuliwe.

2. Indlela yomjovo wesiginali yokuthola ibhodi le-PCB elinephutha

Engeza umthombo wesignali kutheminali yokokufaka, bese ukala i-waveform yephoyinti ngalinye ngokulandelana ukuze ubone ukuthi kuvamile yini ukuthola iphuzu lephutha. Kwesinye isikhathi siphinde sisebenzisa izindlela ezilula, ezinjengokuphatha ama-tweezers ngezandla, kanye nokuthinta amatheminali okokufaka awo wonke amaleveli ukuze sibone ukuthi amatheminali okukhiphayo ayaphendula yini. Lokhu kuvame ukusetshenziswa ekukhuliseni izifunda ezifana nokulalelwayo nevidiyo (kodwa phawula ukuthi ipuleti eliphansi elishisayo Le ndlela ayikwazi ukusetshenziselwa amasekhethi ane-voltage ephezulu noma ama-high voltage circuits, ngaphandle kwalokho angabangela ukushaqeka kukagesi).

Uma kungekho mpendulo ezingeni langaphambilini, kodwa kunempendulo ezingeni elilandelayo, kusho ukuthi inkinga ileleveli yangaphambilini futhi kufanele ihlolwe.

3. Ezinye izindlela zokuthola amabhodi e-PCB anephutha

Ziningi ezinye izindlela zokuthola amaphuzu anephutha, njengokubuka, ukulalela, ukuhogela, ukuthinta, njll.

“Ukubona” ​​ukubona ukuthi kukhona yini umonakalo osobala wemishini engxenyeni, njengokuqhekeka, ukushisa, ukuguqulwa, njll;

“Ukulalela” kusho ukulalela ukuthi ngabe umsindo osebenzayo ujwayelekile yini, isibonelo, into okungafanele ikhale ukukhala, indawo okufanele ikhale ngayo ayikhali noma umsindo ungavamile, njll.;

“Ukuhogela” ukuhlola ukuthi alikho yini iphunga elingajwayelekile, njengephunga lokusha, iphunga le-capacitor electrolyte, njll. Kubasebenzi abanolwazi lokulungisa izinto zikagesi, bayazwela kakhulu kulawa phunga;

“Ukuthinta” ukuhlola ukuthi izinga lokushisa ledivayisi lijwayelekile yini ngesandla, isibonelo, kushisa kakhulu noma kubanda kakhulu.

Some power devices will heat up when they work. If they are cold to the touch, it can basically be judged that they are not working. But if the place that shouldn’t be hot is hot or the place that should be hot is too hot, that won’t work either.

Kuma-transistors wamandla ajwayelekile, ama-voltage regulator chips, njll., kulungile ngokuphelele ukusebenza ngaphansi kwama-degree angama-70. Uyini umqondo wama-degree angama-70? Uma ucindezela isandla sakho phezulu, ungasibamba imizuzwana engaphezu kwemithathu, kusho ukuthi izinga lokushisa lingaphansi kuka-70 degrees (qaphela ukuthi kufanele usithinte kancane kuqala, futhi ungazishisi izandla zakho).