Fotoana izao handinihana ny pitsopitsony sasany amin’ny fikarohana Birao PCB, mba hiomanana tsara kokoa hiantohana ny kalitaon’ny vokatra. Rehefa mamantatra ny birao PCB dia tokony hitandrina ny saina 9 manaraka.

1. Fady mafy ny mampiasa ireo fitaovana fitsapana ifototra mba hifandraisana amin’ny fahitalavitra mivantana, feo, horonan-tsary ary fitaovana hafa eo amin’ny takelaka farany ambany hahitana ny tabilao PCB tsy misy mpanova mitoka-monina.

Aza manandrana mivantana ireo fitaovana TV, audio, ary horonan-tsary raha tsy misy mpanova mitokana herinaratra amin’ny fitaovana mifototra. Na dia amin’ny ankapobeny aza ny mpitam-boky dia manana mpanova herinaratra, rehefa tratry ny hery famoahana manokana na lehibe kokoa amin’ny natioran’ny famatsiana herinaratra dia tsy mahalala firy momba ny fahita amin’ny fahitalavitra na stereo, dia ataovy mazava tsara fa voadidy ny chassis masinina, raha tsy izany dia mora be sy gorodona mivantana Ny televiziona, feo ary kojakoja famatsiana herinaratra hafa, niely tamin’ny faritra miharo, tohiny hafa.

2. Tandremo ny fahombiazan’ny insolation an’ny vy misy solika rehefa mahita ny tabilao PCB

Tsy azo atao ny mampiasa ny vy manitsaka amin’ny hery velona. Mba hahazoana antoka fa tsy velona ny vy mpamadika dia tsara kokoa raha totoina ny akoran’ny vy solder. Tokony hitandrina kokoa ny circuit MOS, ary azo antoka kokoa ny mampiasa ny vy mandeha amin’ny volt-low amin’ny 6-8V.

3. Alohan’ny hamantarana ny tabilao PCB dia tokony ho fantatsika ny fitsipiky ny fiasan’ny faritra miharo sy ny fizaran-tany mifandraika amin’izany

Alohan’ny hijerena sy hanamboarana ny boriborintany efa tafiditra dia tokony ho fantatsika aloha ny fiasan’ny boribory miharo, ny faribolana anatiny, ny masontsivana elektrika lehibe, ny andraikitry ny pin tsirairay sy ny herinaratra mahazatra, ny volan’ny pin ary ny fitsipika iasan’ny faritra misy ny peripheral singa. Raha misy ireo fepetra ireo dia mora kokoa ny famakafakana sy ny fanaraha-maso.

4, test board PCB dia tsy miteraka faritra fohy eo anelanelan’ny tsimatra

Ny fandrefesana ny voltre na ny oscilloscope probe testform form, ny penina na ny probe dia tsy miteraka lalan-kely eo anelanelan’ny tsimatra amin’ilay faritra miharo noho ny fivezivezena, tsara kokoa raha ampifandraisina mivantana amin’ireo tsimatra amin’ny faritra misy ny pirinty peripheral ho an’ny fandrefesana. Ny làlana fohy eo no ho eo dia mety hanimba ny faritra INTEGRATED, noho izany dia tokony hotandremana bebe kokoa rehefa manadinana boribory feno fonosana CMOS mifono fonosana.

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

Rehefa refesina ny voltatran’ny DC an’ireo tsimatra boribory tafiditra ao dia ampiasao multimeter iray izay lehibe kokoa noho 20K ω / V ny fanoherana anatiny; raha tsy izany dia hisy lesoka fandrefesana lehibe ho an’ny voltages pin sasany.

6. Tandremo ny famafana ny hafanana mihodina tariby rehefa mamantatra ny tabilao 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, PCB takelaka fitarihana firaka dia tokony ho antonony

Raha ilaina ny manampy singa peripheral hanoloana ny ampahany simba ao anatin’ny faritra miharo dia tokony hofidina ny singa kely ary tokony ho antonony ny tariby hisorohana ny fampiraisana parasitika tsy ilaina, indrindra ny fiatrehana ny fiafarana eo anelanelan’ny circuit amplifier audio amplifier sy ny circuit preamplifier.

8. Hamarino tsara ny kalitaon’ny welding amin’ny birao PCB

Rehefa tena mihodina ny fehin-kibo, ny fanangonan-tsolika sy ny mason-koditra dia mora miteraka welding virtoaly. Ny fotoan’ny welding dia matetika tsy mihoatra ny 3 segondra, ary ny herin’ny vy soldering dia manodidina ny 25W. Ny tariby miharo dia nodiovina mba hijerena tsara, tsara kokoa ny mampiasa ohmmeter handrefesana raha misy làlana fohy eo anelanelan’ny tsimatra, hamafiso ny fisehoan’ny adhesion solder ary avy eo alefa ny famatsiana herinaratra.

9, ny fahitana ny takelaka PCB dia tsy mamaritra mora ny fahasimban’ny fizaran-tany miharo

Do not easily judge that the integrated circuit is damaged. Satria ny ankamaroan’ny boribory miharo dia mifamatotra mivantana, raha vantany vao tsy ara-dalàna ny fizaran-tany, dia mety hitarika fiovan’ny herinaratra marobe, ary ireo fiovana ireo dia tsy voatery ho vokatry ny fahasimban’ny boribory miharo, ary amin’ny tranga sasany, ny refin’ny pin dia mifanaraka amin’ny na manakaiky ny sanda ara-dalàna, mety tsy ho afaka aseho fa tsara ny circuit mifangaro. Satria ny lesoka malefaka sasany dia tsy miteraka fiovan’ny herinaratra DC.

PCB board debugging method

Ho an’ny birao vaovao PCB izay naverina fotsiny dia tokony hojerentsika aloha raha misy ny olana eo amin’ny solaitrabe, toy ny hoe misy triatra miharihary, na misy faritra fohy, faritra misokatra ary tranga hafa. If necessary, check that the resistance between the power supply and the ground is large enough.

Ho an’ny birao fizaran-tany vao noforonina, matetika ny debugging dia tojo fahasahiranana sasany, indrindra rehefa lehibe kokoa ny tabilao, singa maro kokoa, matetika no tsy mahalala ny fomba hanombohana. Fa raha mahafehy fomba debugging mety ianao dia hahazo indroa ny valiny amin’ny antsasaky ny ezaka.

Fomba famafana ny birao 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, ary avy eo ny singa fametrahana. Module mahaleo tena, raha tsy azonao antoka fa miasa tsara izy ireo, dia tsara kokoa ny tsy mametraka azy rehetra, fa ny ampahany amin’ny fametrahana (ho an’ny faritra kely, azo apetraka indray mandeha), mba ho mora ny mamantatra ny lesoka isan-karazany, ka rehefa sendra olana ianao dia aza hainao ny manomboka.

Generally speaking, you can install the power supply part first, and then check whether the power supply output voltage is normal. Raha tsy dia azonao antoka loatra ny herinao (na dia ianao aza, dia ampandrenesina ianao hanisy fuse, sao sanatria), azonao atao ny mieritreritra ny mampiasa mpanitsy herinaratra azo ovaina miaraka amina famerana ankehitriny.

Ataovy mialoha ny fiarovana ankehitriny, ary avy eo miakatra tsikelikely ny lanjan’ny herinaratra an’ny mpanome herinaratra, ary araho ny fidiran’ny herinaratra, ny herinaratra fampidirana ary ny herin’ny output. If no overcurrent protection occurs and the output voltage is normal, the power supply is OK. Raha tsy izany dia esory ny famatsian-jiro, tadiavo ny lesoka, ary avereno ireo dingana etsy ambony mandra-pahatongan’ny normal ny famatsiana herinaratra.

3, avy eo atsangano tsikelikely ireo modules hafa, apetraka ny module tsirairay, ny fahefana amin’ny fitsapana, ny herinaratra arakaraka ireo dingana etsy ambony, mba hialana amin’ny fandosirana be loatra sy handoroana ireo singa noho ny lesoka tamin’ny famolavolana na ny fametahana hadisoana.

Tadiavo ny vahaolana amin’ny tabilao PCB diso

1. Fatrao ny malefaka hahitanao ny tabilao PCB tsy mety

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. Ny triode silikika mahazatra, ohatra, dia hanana volavolan-tsolika BE manodidina ny 0.7V sy ny tadin’ny CE eo amin’ny 0.3V na latsaka. Raha ny triode dia manana voltam-pifandraisana BE lehibe kokoa noho ny 0.7V (afa-tsy ny triode manokana toa ny fantsom-pamantarana Darlington), dia mety hisokatra ny fihaonana BE.

2, fomba fampidirana signal mba hahitana ny tabilao PCB lesoka

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. Indraindray koa izahay dia hampiasa fomba tsotra kokoa, toy ny mitazona tweezer hikitika ny faran’ny fidirana amin’ny ambaratonga rehetra hahitana raha misy ny fiatraikany eo amin’ny fantsona fivoahana, izay matetika ampiasaina amin’ny feon-tsivana fanamafisam-peo (fa tokony homarihina fa ity fomba ity dia tsy azo ampiasaina amin’ny boriborintany misy takelaka mafana na boribory avo lenta, raha tsy izany dia mety hiteraka fikororohana herinaratra). Raha tsy misy ny fihetsika alohan’ny hikasika, ary misy ny fihetsika aorian’ny fikasihana, dia mampiseho fa ny olana dia teo amin’ny ambaratonga teo aloha, tokony hifantoka amin’ny fizahana.

3. Fomba hafa hitadiavana ireo tabilao PCB tsy mety

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

Ny “jereo” dia ny hijerena raha misy miharihary ny fahasimban’ny mekanika amin’ireo singa, toy ny fahatapahana, ny mainty, ny fanovana, sns.

Ny “mihaino” dia ny fihainoana raha ara-dalàna ny feon’ny asa, toy ny zavatra sasany tsy tokony haneno ao anaty peratra, tsy miantso ny peratra na tsy mahazatra ny feo;

Ny “fofona” dia ny manamarina raha misy fofona, toy ny fofon’ny fandoroana, ny tsiro electrolyte capacitor, ho an’ireo mpiasa elektronika efa za-draharaha, dia tena mora tohina amin’ireo fofona ireo;

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

Fitaovana herinaratra sasany, rehefa miasa, hafanana, raha mangatsiaka ny mikasika azy, azonao atao tsara ny mitsara fa tsy mandeha izany. 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. Inona no dikan’ny 70 degre? 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).