Cuaj qhov kev nkag siab zoo thiab cov txheej txheem ntawm kev kuaj xyuas PCB

cuaj txoj kev xav ntawm PCB soj ntsuam

1. Nws yog txwv tsis pub siv cov cuab yeej siv hauv av kom kov lub TV nyob, suab, video thiab lwm yam khoom siv hauv qab phaj los kuaj PCB pawg thawj coj saib yam tsis muaj qhov hloov pauv hloov pauv.

Nws yog nruj me ntsis txwv tsis pub ncaj qha mus kuaj TV, suab, video thiab lwm yam khoom siv yam tsis muaj lub hwj chim rho tawm transformer nrog cov twj paj nruag thiab cov cuab yeej siv hauv av.

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Txawm hais tias cov xov tooj cua dav dav hauv xov tooj cua muaj lub zog hloov pauv, thaum koj tuaj rau hauv kev sib cuag nrog ntau lub TV tshwj xeeb lossis cov khoom siv suab, tshwj xeeb tshaj yog cov khoom siv hluav taws xob lossis cov khoom siv hluav taws xob siv, koj yuav tsum xub paub seb lub chassis ntawm lub tshuab puas raug them. , txwv tsis pub nws yuav yooj yim heev Lub TV, suab thiab lwm yam khoom siv uas them nrog lub backplane ua rau luv luv Circuit Court ntawm lub hwj chim mov, uas cuam tshuam rau cov kev sib txuas hauv Circuit Court, ua rau kev nthuav dav ntxiv ntawm qhov txhaum.

2. Ua tib zoo saib xyuas cov rwb thaiv tsev ntawm cov hluav taws xob soldering hlau thaum kuaj PCB board

Nws tsis raug tso cai siv cov hlau soldering rau soldering nrog lub hwj chim. Xyuas kom tseeb tias cov hlau soldering tsis raug them. Nws yog qhov zoo tshaj plaws rau hauv av lub plhaub ntawm cov hlau soldering. Ceev faj ntxiv nrog rau MOS Circuit Court. Nws muaj kev nyab xeeb dua los siv lub tshuab hluav taws xob tsawg ntawm 6 ~ 8V.

3. Ua ntej kuaj lub rooj tsavxwm PCB, nkag siab txog cov ntsiab lus ua haujlwm ntawm kev sib xyaw ua ke thiab cov khoom sib txuas

Ua ntej yuav tshuaj xyuas thiab kho qhov sib xyaw ua ke, koj yuav tsum xub paub txog kev ua haujlwm ntawm kev siv hluav taws xob sib xyaw ua ke, kev siv hluav taws xob sab hauv, lub ntsiab hluav taws xob tsis zoo, lub luag haujlwm ntawm txhua tus pin, thiab qhov qub voltage ntawm tus pin, waveform thiab kev ua haujlwm. lub hauv paus ntsiab lus ntawm Circuit Court tsim ntawm peripheral Cheebtsam.

Yog tias cov xwm txheej saum toj no tau ua tiav, kev tshuaj xyuas thiab tshuaj xyuas yuav yooj yim dua.

4. Tsis txhob ua rau luv luv ntawm cov pins thaum kuaj lub rooj tsavxwm PCB

Thaum ntsuas qhov ntsuas hluav taws xob lossis ntsuas qhov nthwv dej nrog kev sojntsuam oscilloscope, tsis txhob ua rau luv luv ntawm cov pins ntawm lub voj voog sib txuas vim yog zawv zawg ntawm qhov kev xeem coj lossis kev sojntsuam. Nws yog qhov zoo tshaj plaws los ntsuas ntawm peripheral luam tawm Circuit Court ncaj qha rau cov pins.

Txhua lub sijhawm luv luv tuaj yeem ua rau kev puas tsuaj rau kev sib txuas ua ke. Koj yuav tsum tau ceev faj ntau dua thaum kuaj lub tiaj-pob CMOS integrated circuits.

5. Kev tiv thaiv sab hauv ntawm PCB board kuaj ntsuas yuav tsum loj

Thaum ntsuas qhov hluav taws xob DC ntawm IC pins, ib lub ntsuas hluav taws xob nrog lub ntsuas hluav taws xob sab hauv lub taub hau siab dua 20KΩ / V yuav tsum tau siv, txwv tsis pub yuav muaj qhov yuam kev loj rau qhov voltage ntawm qee tus pins.

6. Ua tib zoo saib xyuas cov cua kub dissipation ntawm lub hwj chim sib xyaw ua ke thaum kuaj xyuas PCB pawg thawj coj saib

Lub zog hluav taws xob sib xyaw ua ke yuav tsum muaj cov cua kub zoo, thiab nws tsis raug tso cai ua haujlwm hauv lub xeev siab zog yam tsis muaj lub dab dej kub.

7. Cov hlau lead ntawm PCB pawg thawj coj saib yuav tsum tau kuaj kom tsim nyog

Yog tias koj xav tau ntxiv cov khoom siv sab nraud los hloov cov khoom puas ntawm cov khoom sib xyaw ua ke, cov khoom me me yuav tsum raug xaiv, thiab cov xaim yuav tsum tsim nyog kom tsis txhob muaj cov kab mob parasitic coupling, tshwj xeeb tshaj yog cov grounding ntawm lub suab lub hwj chim amplifier integrated circuit thiab preamplifier Circuit Court kawg. .

8. Txhawm rau tshuaj xyuas PCB pawg thawj coj saib kom ntseeg tau tias qhov vuam zoo

Thaum soldering, lub solder yog ruaj, thiab tsub zuj zuj ntawm solder thiab pores yuav ua rau cuav soldering. Lub sij hawm soldering feem ntau tsis pub tshaj 3 vib nas this, thiab lub zog ntawm cov hlau soldering yuav tsum yog li 25W nrog cov cua sov sab hauv.

Cov kev sib xyaw ua ke uas tau raug soldered yuav tsum tau ua tib zoo xyuas. Nws yog qhov zoo tshaj plaws los siv lub ohmmeter los ntsuas seb puas muaj qhov luv luv ntawm cov pins, paub meej tias tsis muaj cov nplaum nplaum, thiab tom qab ntawd tig lub zog.

9. Tsis txhob yooj yim txiav txim siab qhov kev puas tsuaj ntawm kev sib koom ua ke thaum kuaj lub rooj tsav xwm PCB

Tsis txhob txiav txim siab tias qhov sib xyaw ua ke ntawm Circuit Court puas yooj yim. Vim tias feem ntau ntawm cov kab hluav taws xob sib xyaw ua ke ncaj qha, ib zaug ib lub voj voog txawv txav, nws yuav ua rau muaj ntau yam kev hloov pauv, thiab cov kev hloov no tsis tas yuav tshwm sim los ntawm kev puas tsuaj rau lub voj voog sib xyaw.

Tsis tas li ntawd, qee zaum, thaum ntsuas qhov ntsuas hluav taws xob ntawm txhua tus pin sib tw lossis nyob ze rau tus nqi ib txwm, nws yuav tsis yog ib txwm qhia tias kev sib xyaw ua ke zoo. Vim hais tias EDA365 lub rooj sib tham hauv hluav taws xob pom tau tias qee qhov kev ua tsis zoo yuav tsis ua rau muaj kev hloov pauv hauv DC voltage.

PCB pawg debugging txoj kev

Rau lub rooj tsavxwm PCB tshiab uas nyuam qhuav tau rov qab los, EDA365 Electronics Forum xav kom koj ua ntej saib seb puas muaj teeb meem ntawm lub rooj tsavxwm, xws li seb puas muaj cov kab nrib pleb, luv Circuit Court, qhib circuits, thiab lwm yam. Yog tias tsim nyog, xyuas seb lub kev tiv thaiv ntawm lub hwj chim mov thiab hauv av hlau yog loj txaus.

Rau lub rooj tsavxwm tshiab uas tsim los, kev debugging feem ntau ntsib qee qhov teeb meem, tshwj xeeb tshaj yog thaum lub rooj tsavxwm loj thiab muaj ntau yam, nws feem ntau tsis tuaj yeem pib. Tab sis yog tias koj paub cov txheej txheem debugging tsim nyog, debugging yuav tau txais ob zaug qhov tshwm sim nrog ib nrab ntawm kev siv zog.

PCB board debugging cov kauj ruam:

1. Rau lub rooj tsavxwm PCB tshiab uas nyuam qhuav tau muab rov qab, peb yuav tsum xub saib xyuas seb puas muaj teeb meem ntawm lub rooj tsavxwm, xws li seb puas muaj cov kab nrib pleb, luv Circuit Court, qhib circuits, thiab lwm yam. Yog tias tsim nyog, xyuas seb qhov kev tiv thaiv ntawm lub hwj chim mov thiab hauv av hlau yog loj txaus.

2. Tom qab ntawd cov khoom raug teeb tsa. Kev ywj pheej modules, yog tias koj tsis paub meej tias lawv ua haujlwm zoo, nws yog qhov zoo tshaj kom tsis txhob nruab tag nrho lawv, tab sis rau nruab ib feem ntawm ib feem (rau cov circuits me me, koj tuaj yeem nruab lawv tag nrho ib zaug), kom nws yooj yim. los txiav txim qhov txhaum ntau. Tsis txhob muaj teeb meem pib thaum koj ntsib teeb meem.

Feem ntau hais lus, koj tuaj yeem nruab lub hwj huam mov ua ntej, thiab tom qab ntawd muab hluav taws xob los xyuas seb qhov tso zis hluav taws xob ntawm lub hwj chim yog qhov qub. Yog tias koj tsis muaj kev ntseeg siab ntau thaum muaj hluav taws xob (txawm tias koj paub tseeb, nws raug nquahu kom koj ntxiv lub fuse, tsuas yog nyob rau hauv rooj plaub), xav txog kev siv cov khoom siv hluav taws xob kho tau nrog kev txwv tam sim no.

Preset lub overcurrent tiv thaiv tam sim no ua ntej, ces maj mam nce tus nqi voltage ntawm cov tswj fais fab mov, thiab saib xyuas cov input tam sim no, input voltage, thiab output voltage. Yog tias tsis muaj kev tiv thaiv overcurrent thiab lwm yam teeb meem thaum lub sij hawm hloov kho, thiab cov zis voltage tau mus txog qhov qub, lub hwj huam mov yog OK. Txwv tsis pub, disconnect lub fais fab mov, nrhiav qhov txhaum, thiab rov ua cov kauj ruam saum toj no kom txog rau thaum lub hwj chim mov zoo li qub.

3. Tom ntej no, nruab lwm cov modules maj mam. Tom qab txhua qhov module raug teeb tsa, lub hwj chim rau thiab sim nws. Thaum lub hwj chim rau, ua raws li cov kauj ruam saum toj no kom tsis txhob dhau-tam sim no thiab hlawv tawm cov khoom vim yog tsim tsis raug lossis / thiab teeb meem kev teeb tsa.

Nrhiav txoj hauv kev ntawm PCB pawg thawj coj saib tsis ua haujlwm

1. Nrhiav faulty PCB board los ntawm kev ntsuas voltage txoj kev

Thawj qhov kom paub meej yog seb qhov hluav taws xob ntawm lub hwj chim pins ntawm txhua lub nti yog qhov qub, thiab tom qab ntawd xyuas seb qhov sib txawv siv hluav taws xob zoo li cas. Tsis tas li ntawd, EDA365 hluav taws xob lub rooj sab laj ceeb toom: kuj paub meej tias qhov ua haujlwm voltage ntawm txhua qhov chaw yog qhov qub, thiab lwm yam.

Piv txwv li, thaum ib tug dav silicon transistor qhib, BE junction voltage yog hais txog 0.7V, thaum lub CE hlws ris voltage yog hais txog 0.3V los yog tsawg dua. Yog tias BE junction voltage ntawm lub transistor ntau dua 0.7V (tshwj tsis yog rau cov transistors tshwj xeeb, xws li Darlington, thiab lwm yam), nws yuav yog qhov BE junction qhib.

2. Kev txhaj tshuaj tiv thaiv kab mob txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txiav txim

Ntxiv cov teeb liab qhov chaw mus rau lub input davhlau ya nyob twg, thiab tom qab ntawd ntsuas lub waveform ntawm txhua qhov taw tes nyob rau hauv lem saib seb nws puas yog ib txwm mus nrhiav qhov txhaum point. Qee lub sij hawm peb kuj siv txoj kev yooj yim dua, xws li tuav lub tweezers nrog peb txhais tes, thiab kov cov tswv yim terminals ntawm txhua qib kom pom tias cov zis terminals teb. Qhov no feem ntau yog siv hauv amplifying circuits xws li suab thiab yees duab (tab sis nco ntsoov tias lub phaj kub hauv qab no tsis tuaj yeem siv rau circuits nrog high voltage lossis high voltage circuits, txwv tsis pub nws yuav ua rau hluav taws xob poob).

Yog tias tsis muaj lus teb rau qib dhau los, tab sis muaj cov lus teb rau qib tom ntej, nws txhais tau tias qhov teeb meem nyob rau qib dhau los thiab yuav tsum tau kuaj xyuas.

3. Lwm txoj hauv kev los nrhiav cov khoom siv PCB yuam kev

Muaj ntau ntau txoj hauv kev los nrhiav cov ntsiab lus txhaum, xws li saib, mloog, hnov ​​​​tsw, kov, thiab lwm yam.

“Saib” yog saib seb puas muaj kev puas tsuaj rau cov khoom siv, xws li tawg, hlawv, deformation, thiab lwm yam;

“Listening” txhais tau hais tias mloog seb lub suab ua haujlwm zoo li cas, piv txwv li, ib yam dab tsi uas yuav tsum tsis txhob nrov yog lub suab nrov, qhov chaw uas yuav tsum tau suab tsis nrov lossis lub suab txawv txav, thiab lwm yam.;

“Smell” yog los xyuas seb puas muaj cov ntxhiab tsw tshwj xeeb, xws li tsis hnov ​​tsw ntawm qhov kub hnyiab, tsis hnov ​​​​tsw ntawm capacitor electrolyte, thiab lwm yam. Rau cov neeg ua haujlwm paub txog hluav taws xob, lawv muaj kev nkag siab rau cov ntxhiab tsw;

“Kov” yog ntsuas seb qhov ntsuas kub ntawm lub cuab yeej yog li cas los ntawm tes, piv txwv li, nws kub dhau lossis txias dhau.

Qee cov khoom siv hluav taws xob yuav ua kom sov thaum lawv ua haujlwm. Yog tias lawv txias rau qhov kov, nws tuaj yeem txiav txim siab tias lawv tsis ua haujlwm. Tab sis yog tias qhov chaw uas yuav tsum tsis txhob kub yog qhov kub los yog qhov chaw uas yuav tsum kub yog kub heev, qhov ntawd yuav tsis ua hauj lwm.

Rau cov fais fab transistors, voltage regulator chips, thiab lwm yam, nws yog zoo kiag li ua hauj lwm hauv qab no 70 degrees. Lub tswvyim ntawm 70 degrees yog dab tsi? Yog tias koj nias koj txhais tes, koj tuaj yeem tuav nws ntev tshaj li peb vib nas this, nws txhais tau tias qhov kub thiab txias qis dua 70 degrees (nco ntsoov tias koj yuav tsum kov nws ua ntej, thiab tsis txhob hlawv koj txhais tes).