Yeyiphi indima edlalwa zizo “pads ezikhethekileyo” kwiPCB?

 

1. Iphedi yeentyatyambo zePlum.

PCB

I-1: Umngxuma wokulungisa kufuneka ungabi-metalized. Ngexesha le-wave soldering, ukuba umngxuma wokulungisa ngumgodi owenziwe ngesinyithi, i-tin iya kuwuvala umngxuma ngexesha lokuphinda kufakwe i-solder.

2. Ukulungisa imingxunya ekhwelayo njenge pads quincunx ngokuqhelekileyo isetyenziselwa ukukhwela umngxuma womnatha we-GND, kuba ngokubanzi i-PCB yobhedu isetyenziselwa ukubeka ubhedu kwinethiwekhi ye-GND. Emva kokuba imingxunya ye-quincunx ifakwe kunye namacandelo eqokobhe le-PCB, enyanisweni, i-GND iqhagamshelwe emhlabeni. Ngamanye amaxesha, iqokobhe lePCB lidlala indima yokukhusela. Kakade ke, abanye abafuni kudibanisa umngxuma wokunyuka kwinethiwekhi ye-GND.

3. Umngxuma wesikrufu sesinyithi unokucudiswa, nto leyo ekhokelela ekubeni ube nguziro wemeko yokumiselwa komhlaba nokungashukumi, nto leyo ebangela ukuba inkqubo ingaqheleki ngendlela engaqhelekanga. Umngxuma otyatyambileyo weplum, nokuba lutshintsha njani na uxinezeleko, unokuhlala usigcina isikrufu sisekelwe phantsi.

 

2. Iphedi yeentyatyambo ezinqamlezileyo.

PCB

Iipads zentyatyambo ezinqamlezayo zikwabizwa ngokuba yi-thermal pads, iipads zomoya ezishushu, njl.

1 Xa iphedi yakho igutyiwe. Ipateni yomnqamlezo inokunciphisa indawo yocingo lomhlaba, icothise isantya sokutshatyalaliswa kobushushu, kwaye iququzelele i-welding.

2 Xa i-PCB yakho ifuna ukufakwa komatshini kunye nomatshini wokuphinda udibanise, i-pattern-pattern pad inokuthintela i-PCB ekuxobukeni (kuba ubushushu obuninzi bufunekayo ukunyibilikisa i-solder paste)

 

3. iphedi yeenyembezi

 

PCB

Ii-Teardrop luqhagamshelo oluvuza ngokugqithisileyo phakathi kwephedi kunye nocingo okanye ucingo kunye ne-via. Injongo ye-teardrop kukuphepha indawo yoqhagamshelwano phakathi kwentambo kunye ne-pad okanye ucingo kunye nokudlula xa ibhodi yesekethe ibethwe ngamandla amakhulu angaphandle. Ukuqhawula, ukongeza, ukuseta i-teardrops kunokwenza ukuba ibhodi yesekethe ye-PCB ibonakale intle ngakumbi.

Umsebenzi we-teardrop kukuphepha ukuncipha ngokukhawuleza kobubanzi bomgca wesignali kunye nokubangela ukubonakaliswa, okunokwenza uxhulumaniso phakathi komkhondo kunye necandelo lecandelo libe yinguqu egudileyo, kunye nokusombulula ingxaki yokuba uxhulumaniso phakathi kwe-pad kunye ne-trace. yaphuka ngokulula.

1. Xa i-soldering, inokukhusela i-pad kwaye igweme ukuwa kwi-pad ngenxa ye-soldering ezininzi.

2. Yomeleza ukuthembeka koqhagamshelwano (ukuveliswa kunokuphepha ukulinganisa okungalinganiyo, ukuqhekeka okubangelwa ngokutenxa, njl.)

3. I-impedance epholileyo, ukunciphisa ukutsiba okubukhali kwe-impedance

Kuyilo lwebhodi yesiphaluka, ukwenzela ukuba i-pad ibe yomelele kwaye ithintele i-pad kunye nocingo ukuba luqhawulwe ngexesha lokwenziwa komatshini webhodi, ifilimu yobhedu isoloko isetyenziselwa ukulungiselela indawo yokutshintsha phakathi kwepadi kunye nocingo. , emile okweenyembezi, ngoko idla ngokubizwa ngokuba ziiNtyityityityimba (IiNtyityityityityityimba)

 

4. ukukhupha izixhobo

 

 

PCB

Ngaba ukhe wazibona izinto zabanye abantu zokutshintsha amandla zigcine ngabom i-sawtooth engenanto yobhedu phantsi kwe-inductance yendlela eqhelekileyo? Uyintoni umphumo?

Oku kubizwa ngokuba yi-discharge tooth, i-gap yokukhupha okanye i-spark gap.

Umsantsa wentlantsi yipere yoonxantathu abaneengile ezibukhali ezikhomba omnye komnye. Umgama omkhulu phakathi kweminwe yi-10mil kwaye ubuncinane yi-6mil. Enye i-delta isekelwe, kwaye enye idityaniswe kumgca wesignali. Lo nxantathu akalolungu, kodwa wenziwa ngokusebenzisa iileya zefoyile yobhedu kwinkqubo yomzila wePCB. Abanxantathu kufuneka babekwe kumaleko aphezulu e-PCB (i-componentside) kwaye ayinakugqunywa sisigqubuthelo sobuso.

Kuvavanyo lokutshintsha kombane wombane okanye uvavanyo lwe-ESD, amandla ombane aphezulu aya kuveliswa kuzo zombini iziphelo ze-inductor yendlela eqhelekileyo kunye ne-arcing iya kwenzeka. Ukuba ikufuphi nezixhobo ezijikelezileyo, izixhobo ezijikelezileyo zingonakaliswa. Ke ngoko, ityhubhu yokukhupha okanye i-varistor inokudityaniswa ngokuhambelana nokukhawulela i-voltage yayo, ngaloo ndlela idlala indima yokucima i-arc.

Impembelelo yokubeka izixhobo zokukhusela umbane zihle kakhulu, kodwa ixabiso liphezulu kakhulu. Enye indlela yokongeza amazinyo okukhupha kuzo zombini iziphelo ze-inductor yendlela eqhelekileyo ngexesha loyilo lwe-PCB, ukuze i-inductor ikhuphe ngeengcebiso ezimbini zokukhupha, ukuphepha ukukhutshwa kwezinye iindlela, ukuze ujikelezo kunye nefuthe lezixhobo zenqanaba lamva lincitshiswe.

I-gap yokukhupha ayifuni iindleko ezongezelelweyo. Iyakwazi ukutsalwa xa udweba ibhodi ye-pcb, kodwa kubalulekile ukuqaphela ukuba olu hlobo lwe-gap yokukhupha luyi-gap yokukhupha umoya, enokusetyenziswa kuphela kwindawo apho i-ESD yenziwa ngamaxesha athile. Ukuba isetyenziswe kwiimeko apho i-ESD iyenzeka rhoqo, iidiphozithi zekhabhoni ziya kuveliswa kumanqaku amabini angamanxantathu phakathi kwezithuba zokukhupha ngenxa yokukhutshwa rhoqo, okuya kuthi ekugqibeleni kubangele isiphaluka esifutshane kwi-gap yokukhupha kwaye kubangele i-short-circuit yesigxina somqondiso. umgca emhlabeni. Isiphumo sokusilela kwenkqubo.