PCB is the support of circuit components and components in electronic products. It provides electrical connections between circuit elements and devices. Horumarinta degdegga ah ee farsamada korontada, cufnaanta PGB ayaa sare u sii kacaysa. The ability of PCB design to resist interference makes a big difference. Sidaa darteed, qaabeynta PCB. Mabaadiida guud ee naqshadaynta PCB waa in la raaco oo shuruudaha naqshada ka hortagga faragelinta waa in la buuxiyaa.

Mabaadi’da guud ee naqshadaynta PCB

Qaab -dhismeedka qaybaha iyo fiilooyinka ayaa muhiim u ah waxqabadka ugu wanaagsan ee wareegyada elektiroonigga ah. Tayada naqshadeynta wanaagsan. PCB oo leh qiime jaban waa inuu raaco mabaadi’da guud ee soo socda:

1. Qaabka

Marka hore, waa lagama maarmaan in la tixgeliyo cabbirka PCB -ga oo aad u weyn. Marka cabbirka PCB-ga aad u weyn yahay, xariiqa daabacan waa dheer yahay, impedance-ku wuu kordhaa, awoodda buuq-diidka ayaa yaraata, kharashkuna wuu kordhaa. Aad bay u yar tahay, kala -daadinta kuleylku ma fiicna, oo khadadka ku dhow ayaa u nugul faragelinta. Ka dib marka la go’aamiyo cabbirka PCB. Ka dibna hel qaybaha gaarka ah. Ugu dambayn, marka loo eego cutubka shaqaynaya ee wareegga, dhammaan qaybaha wareegga ayaa la dejiyay.

U fiirso mabaadiida soo socota marka la go’aaminayo meesha ay ka kooban yihiin qaybo gaar ah:

(1) Soo gaabi xiriirka ka dhexeeya qaybaha soo noqnoqoshada badan intii suurtogal ah, iskuna day inaad yareyso xuduudaha qaybintooda iyo faragelinta elektromagnetka ee dhexdooda. Qaybaha si dhib yar loo carqaladeeyay waa inaanay aad isugu dhowaan, oo qaybaha soo -gelinta iyo soo -saaridda waa inay ahaadaan kuwo aad u fog.

(2) Waxaa jiri kara farqi aad u sarreeya oo u dhexeeya qaybo ama fiilooyin, sidaa darteed masaafada u dhexeysa waa in la kordhiyaa si looga fogaado wareeg gaaban oo shil ah oo ay keento dheecaan. Qaybaha leh danab aad u sarreeya waa in la dhigaa inta suurtogalka ah meelaha aan si fudud gacanta loogu heli karin inta lagu jiro khaladka.

(3) Qaybo miisaankoodu ka badan yahay 15g. Waa in la xiraa ka dibna alxanka. Kuwani waa weyn yihiin oo culus yihiin. Qaybaha leh qiime kalori sare ma aha in lagu rakibo sabuuradda daabacan, laakiin waa in lagu dhejiyaa mashiinka oo dhan, waana in la tixgeliyaa dhibaatada kala -daadinta kulaylka. Walxaha kuleylka waa in laga fogeeyaa walxaha kululaynta.

(4) ee potentiometer. Gariiradda inductor hagaajin karo. Capacitor doorsooma. Qaabaynta qaybaha la isku hagaajin karo sida microswitch waa inay tixgelisaa shuruudaha dhismaha ee mashiinka oo dhan. Haddii hagaajinta mashiinka, waa in lagu dhejiyaa sabuuradda daabacan ee kor ku xusan si sahlan si loo hagaajiyo meesha; Haddii mashiinka lagu hagaajiyo bannaanka, booskiisa waa in la waafajiyaa booska buunshaha hagaajinta ee ku yaal guddiga shaxanka.

(5) Meesha ay ku yaalliin daloolka meelaynta iyo hagaajinta bareeraha kabaalka daabacaadda waa in meel la iska dhigaa.

Marka loo eego cutubka shaqaynaya ee wareegga. The layout of all components of the circuit shall comply with the following principles:

(1) Diyaarso booska cutub kasta oo wareegsan oo shaqeynaya si waafaqsan habka wareegga, si qaab -dhismeedku ugu habboon yahay socodka signalada iyo tilmaamtu waxay haysaa isla jihada intii suurtogal ah.

(2) Qaybaha asaasiga ah ee wareeg kasta oo shaqeynaya sida xarunta, hareeraheeda si loo fuliyo qaabeynta. Qaybaha waa inay ahaadaan labis. Oo hagaagsan. Si adag ayaa loogu habeeyay PCB. Yaree oo soo gaabi hogaamiyaasha iyo xiriirada ka dhexeeya qaybaha.

(3) For circuits working at high frequencies, the distributed parameters between components should be considered. Wareegyada guud, qaybaha waa in loo habeeyo isbarbaryaac intii suurtogal ah. Habkan, ma aha oo kaliya qurux badan. Oo ay fududahay in la isu geeyo oo la xiro.

(4) Qaybaha ku yaal cidhifka guddiga wareegga, guud ahaan aan ka yarayn 2mm oo ka soo jeeda cidhifka guddiga wareegga. Qaabka ugu fiican ee loox wareegga waa leydi. Dhererka ilaa saamiga ballaadhku waa 3:20 iyo 4: 3. Cabbirka guddiga wareegga ayaa ka weyn 200x150mm. Consideration should be given to the mechanical strength of the circuit board.

2. Fiilooyinka

Mabaadi’da fiilooyinka waa sida soo socota:

(1) Fiilooyinka isbarbar socda ee boosteejada gelinta iyo soo -saarka waa in laga fogaadaa intii suurtogal ah. Waxaa fiican inaad ku darto silig dhulka u dhexeeya fiilooyin si aad uga fogaato isku xirnaanta warcelinta.

(2) Ballaca ugu yar ee siligga daabacan waxaa inta badan lagu go’aamiyaa xoogga adhesion ee u dhexeeya siligga iyo substrate -ka dahaarka iyo qiimaha hadda dhex socda.

Marka dhumucda bireedka naxaasku ay tahay 0.05mm ballacuna yahay 1 ~ 15mm. Wakhtigan illaa 2A, heerkulku kama sarrayn doono 3 ℃, sidaa darteed ballaca siligga ee 1.5mm ayaa buuxin kara shuruudaha. Wareegyada isku -dhafan, gaar ahaan wareegyada dhijitaalka ah, 0.02 ~ 0.3mm ballaca siligga ayaa badanaa la doortaa. Dabcan, u isticmaal xariiq ballaaran inta aad awooddo. Gaar ahaan fiilooyinka korontada iyo fiilooyinka dhulka.

Kala -fogaanshaha ugu yar ee fiilooyinka waxaa inta badan lagu go’aamiyaa iska -caabbinta dahaarka iyo korantada burburka u dhexeysa fiilooyinka marka ay ugu daran tahay. Wareegyada isku -dhafan, gaar ahaan wareegyada dhijitaalka ah, illaa inta geeddi -socodku oggolaanayo, kala -fogaanshuhu wuxuu u yaraan karaa 5 ~ 8mm.

(3) Laabashada siligga la daabacay guud ahaan waxay qaadataa qaanso wareegsan, iyo Xagasha midig ama ku jirta Xaglaha ee wareegga soo noqnoqoshada sare waxay saamayn doontaa waxqabadka korantada. Intaa waxaa dheer, isku day inaad iska ilaaliso adeegsiga aagag waaweyn oo ah bireedka naxaasta, haddii kale. When heated for a long time, copper foil expands and falls off easily. Marka ay tahay in la isticmaalo meelo waaweyn oo naxaas -naxaas ah, waxaa fiican in la isticmaalo shabag. Tani waxay ku habboon tahay in laga saaro foornada naxaasta ah iyo isku -xidhka substrate -ka u dhexeeya kulaylka uu soo saaro gaaska kacsan.

3. Saxanka alxanka

Daloolka dhexe ee suufka waa inuu xoogaa ka weyn yahay dhexroorka rasaasta aaladda. Suuf aad u weyn ayaa fudud in la sameeyo alxanka dalwaddii. Suufka dhexroorka D -ga guud ahaan kama yaraan (D +1.2) mm, halkaas oo D uu yahay daloolka rasaasta. Wareegyada dhijitaalka ah ee cufnaanta sare leh, dhexroorka ugu yar ee suufku waa suurad wacan (D +1.0) mm.

PCB iyo wareegyada tallaabooyinka ka hortagga faragelinta

Naqshadeynta ka hortagga faragelinta ee guddiga wareegga ee daabacan waxay si dhow ula xiriirtaa wareegga gaarka ah. Halkaan waxaa lagu qeexay kaliya dhowr cabbir oo caadi ah ee naqshadeynta faragelinta ka hortagga PCB.

1. Naqshadda fiilada korontada

Marka loo eego xajmiga guddiga wareegga ee daabacan hadda, intii suurtogal ah si loo kordhiyo ballaca khadka korontada, yaree iska caabbinta loop -ka. Isla mar ahaantaana. Samee xarigga korontada. Jihada siligga dhulka ayaa waafaqsan jihada gudbinta xogta, taas oo gacan ka geysaneysa kor u qaadista iska -caabbinta dhawaaqa.

2. Naqshad badan

Mabda’a naqshadaynta siligga dhulka waa:

(1) Dhulka dhijitaalka ah waxaa laga soocaa dhulka analoogga. Haddii ay jiraan wareegyo macquul ah iyo kuwo toosan oo ku yaal guddiga wareegga, u kala dhig sida ugu macquulsan. Dhulka wareegga soo noqnoqoshada hoose waa inuu qaataa hal dhibic oo isbarbar dhiga dhulka inta ugu badan ee suurtogalka ah. Marka xadhigga dhabta ahi adag yahay, qayb ka mid ah wareegga ayaa lagu xidhi karaa taxane ka dibna dhulka oo is barbar socda. High frequency circuit should use multi-point series grounding, grounding should be short and rent, high frequency elements around as far as possible with a large area of grid foil.

(2) Siligga dhulka soo degaya waa inuu ahaadaa mid qaro weyn. Haddii xariijinta dhulka ay aad u dheer tahay, suurtogalnimada soo-dejinta ayaa isbeddeleysa hadda, sidaa darteed waxqabadka buuq-diidka ayaa la dhimayaa. Sidaa darteed siligga dhulka soo degaya waa inuu ka sii dhumuc weyn yahay si uu u dhaafi karo saddex jeer heerka hadda la oggol yahay ee sabuuradda daabacan. Haddii ay suurtogal tahay, xadhigga dhulka hoostiisa waa inuu ka weyn yahay 2 mm illaa 3mm.

(3) Siligga dhulka wuxuu ka kooban yahay loop xiran. Most of the printed board composed only of digital circuit can improve the anti-noise ability of the grounding circuit.

3. Decoupling qaabeynta capacitor

Mid ka mid ah hababka caadiga ah ee naqshadaynta PCB waa in la geeyo awood -siinta ku habboon kala -goynta qayb kasta oo muhiim ah oo ka mid ah guddiga la daabacay. Mabda’a guud ee qaabeynta koronto -dhaliyaha waa:

(1) Dhamaadka soo gelinta korontada waxay ku xiran tahay koronto -dhaliyaha 10 ~ 100uF. Haddii ay suurtogal tahay, waxaa wanaagsan in lagu xiro 100uF ama ka kor.

(2) mabda ‘ahaan, guntin kasta oo IC ah waa in lagu qalabeeyaa korantada dhoobada ee 0.01pF. Haddii booska boodhka ee daabacan uusan ku filnayn, 1 ~ 10pF capacitor ayaa loo diyaarin karaa 4 ~ 8 jajab kasta.

(3) Awoodda buuq-diidka ayaa daciif ah. Aaladaha leh isbeddellada awoodda weyn inta lagu jiro xiritaanka, sida aaladda xusuusta ee RAM.

(4) Hoggaamiyaha koronto-dhaliyaha ma noqon karo mid aad u dheer, gaar ahaan kaarboorka ku-noqnoqoshada badan ma laha hoggaanka. Intaa waxaa dheer, labada qodob ee soo socda waa in la xusaa:

(1 Waxaa ku jira xariiriyaha guddiga daabacan. Gudbinta. Dheecaan baaxad weyn ayaa la soo saari doonaa marka la shaqeynayo badhamada iyo qaybaha kale, iyo wareegga RC ee ka muuqda sawirka ku lifaaqan waa in loo adeegsadaa in lagu nuugo dareeraha hadda socda. Guud ahaan, R waa 1 ~ 2K, iyo C waa 2.2 ~ 47UF.

Caqabad -gelinta 2CMOS waa mid aad u sarreysa oo xasaasi ah, sidaa darteed dhammaadka aan la isticmaalin waa in lagu saleeyaa ama lagu xiraa koronto wanaagsan.