Isishwankathelo ezintandathu PCB Uyilo lwemveliso

1. Ubeko

Okokuqala, cinga ubungakanani PCB. Xa ubungakanani bebhodi yesekethe ye-PCB inkulu kakhulu, umgca oprintiweyo mde, ukunyanzeliswa kuyenyuka, amandla okulwa nengxolo ayancipha kwaye iindleko ziyanda; Ukuba incinci kakhulu, ukusasaza ubushushu kuhlwempuzekile, kwaye imigca ekufutshane kulula ukuba iphazanyiswe. Emva kokumisela ubungakanani bePCB, misela indawo yezinto ezikhethekileyo. Okokugqibela, onke amacandelo esekethe acwangcisiwe ngokungqinelana neeyunithi ezisebenzayo zesekethe.

Le migaqo ilandelayo iya kuqatshelwa xa kumiselwa indawo yezinto ezizodwa:

(1) Nqumamisa i-wiring phakathi kwezinto ezinamaza aphakamileyo kangangoko kunokwenzeka, kwaye uzame ukunciphisa iiparameter zokuhambisa kunye nokuphazamiseka kokubambana ngombane. Izinto ezinokuthi zithintelwe aziyi kuba kufutshane kakhulu komnye nomnye, kwaye igalelo kunye nezinto ezikhutshiweyo ziya kuba kude kangangoko.

(2) Kunokubakho umahluko omkhulu phakathi kwezinto ezithile okanye iingcingo, ke umgama phakathi kwazo kufuneka unyuswe ukunqanda ngengozi isekethe emfutshane ebangelwe kukukhutshwa. Izinto ezinamandla ombane aphezulu ziya kulungiswa kwiindawo ekungekho lula ukuzichukumisa ngexesha lokugunyazisa.

(3) Indawo ekuhlalwa kuyo ngumngxuma wokuma kwepleyiti eprintiweyo kunye nenkxaso esisigxina iya kugcinwa.

Ngokwicandelo lokusebenza kwesekethe, ubeko lwazo zonke izinto zesekethe ziyahambelana nale migaqo ilandelayo:

(1) Hlela indawo nganye yokusebenza kwesekethe ngokuhambelana nokuhamba kwesekethe, yenza ubume bube lula ukuhamba komqondiso, kwaye ugcine umqondiso kwicala elinye kangangoko kunokwenzeka.

(2) Thatha izinto ezingundoqo zesekethe nganye esebenzayo njengeziko kunye nolwakhiwo olujikelezileyo. Amacandelo aya kuba ngokulinganayo, ngokucocekileyo nangokucwangcisiweyo alungelelaniswe kwi-PCB. Izikhokelo kunye nokunxibelelana phakathi kwamacandelo kuya kuncitshiswa kwaye kufutshane kangangoko kunokwenzeka.

(3) Ukusebenza kwesekethe kumaza aphezulu, iiparameter zokuhambisa phakathi kwezinto kufuneka ziqwalaselwe. Kwiisekethe ngokubanzi, izinto ziya kulungiswa ngokuhambelana ngokusemandleni. Ngale ndlela, ayisiyontle kuphela, kodwa kulula nokuhlangana kunye ne-weld, kwaye kulula ukuyivelisa.

(4) Izinto ezifumaneka kumda webhodi yesekethe ngokubanzi azikho ngaphantsi kwe-2mm kude nomda webhodi yesekethe. Eyona milo ilungileyo yebhodi yesekethe luxande. Umlinganiso wenqanaba yi-3: 2 ukuya ku-4: 3. Xa ubukhulu bomhlaba webhodi yesekethe bungaphezulu kwe-200x150mm, amandla oomatshini webhodi yesekethe aya kuqwalaselwa.

2. Iingcingo

Imigaqo ye-wiring imi ngolu hlobo lulandelayo:

(1) Abaqhubi abasetyenzisiweyo kwiitheminali zokufaka kunye nezokuphuma baya kunqanda ukuhambelana okukude kangangoko kunokwenzeka. Kungcono ukongeza ucingo lomhlaba phakathi kwemigca ukunqanda ukudibana kwengxelo.

(2) Ububanzi obuncinci bobumqhubi obushicilelweyo buxhomekeke ikakhulu kukuqina kokubambelela phakathi komqhubi kunye nesiseko se-insing kunye nekhoyo yangoku ehamba ngayo.

(3) Ukugoba kocingo olushicilelweyo kuhlala kuyisetyhula arc, kwaye i-engile elungileyo okanye i-engile efakiweyo iya kuchaphazela ukusebenza kombane kwisekethe ephezulu. Ukongeza, zama ukunqanda ukusebenzisa indawo enkulu yefoyile yobhedu, ngapha koko, ukwanda kwefoyile yobhedu kunye nokuwa kulula ukuvela xa kushushu ixesha elide. Xa kufuneka kusetyenziswe indawo enkulu yobhedu, kufanelekile ukusebenzisa imilo yegridi, efanelekileyo ekupheliseni igesi eguqukayo eveliswa kukufudumeza okuncamathelayo phakathi kwefoyile yobhedu kunye ne-substrate.

3. Iphedi

Umngxunya weziko lephedi (isixhobo esisemgceni) sikhulu kancinci kunesixhobo esikhokelayo sangqa. Ukuba iphedi inkulu kakhulu, kulula ukuyila ngelotha engeyiyo. Ububanzi obungaphandle be-D yephedi ngokubanzi abukho ngaphantsi kwe (D + 1.2) mm, apho i-D yindawo enobungakanani bomngxunya okhokelayo. Kwimijikelezo yedijithali exineneyo, ubuncinci bepali bunokuba yi (D + 1.0) mm.

Amanyathelo ukuphazamiseka Anti for PCB kunye neesekethe:

Uyilo oluchasene nokuphazamiseka kwibhodi yesekethe eprintiweyo isondele kakhulu kwisekethe ethile. Apha, kuphela amanyathelo ambalwa aqhelekileyo kuyilo lokuchasana ne-PCB echazwe.

1. Uyilo lwentambo yamandla

Ngokwangoku ibhodi yesekethe eprintiweyo, zama ukwandisa ububanzi belayini yamandla kunye nokunciphisa ukuxhathisa iluphu. Kwangelo xesha, yenza ulwalathiso lwelayini yamandla kunye nocingo lomhlaba oluhambelana nolwalathiso lwedatha, enceda ekuphuculeni amandla engxolo.

2. Uyilo oluninzi

Imigaqo yoyilo lwentambo yomhlaba zezi:

(1) I-Digital kunye ne-analog zahluliwe. Ukuba yomibini imijikelezo enengqiqo kunye neesekethe ezilayini kwibhodi yesekethe, ziya kwahlulwa kangangoko kunokwenzeka. Inqaku elinye lokulinganisa umhlaba liya kwamkelwa kumhlaba wesekethe esezantsi kangangoko kunokwenzeka. Ukuba kunzima ukudibanisa i-wiring eyiyo, inokudityaniswa ngokungafaniyo kuthotho kwaye emva koko idityaniswe ngokuhambelana. Amanqaku e-Multi-series grounding aya kwamkelwa kwisiphaluka esiphakamileyo, ucingo lomhlaba luya kufutshane kwaye luqeshwe, kwaye iigridi ezinjengommandla omkhulu womhlaba ziya kusetyenziswa kwiindawo ezinamaza aphakamileyo kangangoko kunokwenzeka.

(2) Olu cingo lomhlaba luya kuba lukhulu kangangoko. Ukuba ucingo olusezantsi lwenziwe ngocingo oluthungiweyo, utshintsho olunokubakho lomhlaba kunye notshintsho lwangoku, ukwenzela ukuba ukusebenza kwengxolo echaseneyo kuncitshiswe. Ke ngoko, ucingo lomhlaba kufuneka lutyebile ukuze kudlule kathathu okwangoku okuvumelekileyo kwibhodi eprintiweyo. Ukuba kunokwenzeka, ucingo olungumhlaba luya kuba ngaphezulu kwe-2 ~ 3mm.

(3) Ucingo olusezantsi lwenza iluphu evaliweyo. Kwiibhodi eziprintiweyo ezenziwa kuphela ziisekethe zedijithali, isekethe yomhlaba icwangcisiwe kwilogo yesihloko, esinokuthi siphucule amandla engxolo.

4. Ukucutha uqwalaselo lwe-capacitor

Enye yeendlela eziqhelekileyo zoyilo lwe-PCB kukumisela izixhobo ezifanelekileyo zokudibanisa izixhobo kwindawo nganye ephambili ye-PCB. Umgaqo wokumiselwa ngokubanzi wokuchithwa kwe-capacitor yile:

(1) Isiphelo segalelo lamandla sidityaniswe ne-10 ~ 100uF capacitor electrolytic. Ukuba kunokwenzeka, kungcono ukudibanisa ngaphezulu kwe-100uF.

(2) Ngokomgaqo, i-chip yesekethe nganye edityanisiweyo iya kuxhotyiswa nge-0.01uF ~ 0.1uF ceramic chip capacitor. Kwimeko yokungabikho kwesithuba kwibhodi eprintiweyo, i-1 ~ 10PF capacitor inokucwangciswa rhoqo ngeetshiphusi ezi-4 ~ 8.

(3) Izixhobo ezinengxolo ebuthathaka kunye notshintsho olukhulu lwamandla ngexesha lokucima, ezinje ngezixhobo zokugcina i-RAM kunye neROM, ukudibanisa izixhobo zokucoca ziya kudityaniswa ngokuthe ngqo phakathi komtya wamandla kunye nocingo lomhlaba lwe-chip.

5. Ngoyilo lomngxuma

Kuyilo olukhawulezayo lwePCB, vias ezibonakala ngathi zilula zihlala zizisa iziphumo ezibi kuyilo lwesekethe. Ukuze kuncitshiswe iziphumo ezibi ezibangelwa zizifunxi-gazi ze-vias, sinokuzama konke okusemandleni ethu kuyilo

(1) Ukujonga iindleko kunye nomgangatho wophawu, kukhethwe ubungakanani obufanelekileyo ngokobungakanani. Umzekelo, kuyilo lwemodyuli ye-PCB yemodyuli eyi-6-10, kungcono ukhethe i-10 / 20MIL (ukubhola / pad) vias. Kwezinye iibhodi ezinobungakanani obukhulu bezinto ezincinci, unokuzama ukusebenzisa i-8 / 18mil vias. Phantsi kweemeko zobugcisa zangoku, kunzima ukusebenzisa encinci ngemingxunya (xa ubunzulu bomngxuma budlula amaxesha ama-6 ubukhulu bokubhola, akunakwenzeka ukuba kuqinisekiswe ukuba udonga lomngxuma lunokugutyungelwa ngobhedu); Kwimihlaba yamandla okanye yomhlaba, ubukhulu obukhulu bunokuqwalaselwa ukunciphisa impedance

(2) Ukuhamba komqondiso kwibhodi ye-PCB akuyi kutshintsha iileya kangangoko kunokwenzeka, oko kukuthi, ii-vias ezingeyomfuneko azisayi kusetyenziswa kangangoko kunokwenzeka

(3) Izikhonkwane zonikezelo lwamandla kunye nomhlaba kufuneka zigutyulwe kufutshane. Ngokufutshane ukukhokela phakathi kokudlula kunye nepini, kungcono

(4) Beka ii-vias ezisisiseko kufutshane ne-vias zotshintsho lomaleko wesiginali ukubonelela ngesekethe ekufuphi kumqondiso. Unokubeka inani elikhulu le-vias ezingafunekiyo kwi-PCB

6. Amava athile ekunciphiseni ingxolo nokuphazamiseka kombane

(1) Ukuba ungasebenzisa iichips ezinesantya esiphantsi, awudingi zinejubane eziphezulu. Iichips ezikhawulezayo zisetyenziswa kwiindawo eziphambili

(2) Uthotho lwezinto ezichasayo zingasetyenziselwa ukunciphisa isantya sokutsiba kwamanqwanqwa aphezulu nasezantsi kwisekethe yolawulo.

(3) Zama ukubonelela ngolunye uhlobo lokuthambisa ukuphinda udlulise, njl, njl

(4) Sebenzisa iwotshi yamaxesha esezantsi ehlangabezana neemfuno zenkqubo.

(5) Ikloko iya kuba kufutshane kangangoko kwisixhobo esisebenzisa iwotshi. Igobolondo le-quartz crystal oscillator iya kuncitshiswa. Indawo yewotshi iya kungqongwa lucingo lomhlaba. Umgca wewotshi uya kuba mfutshane kangangoko. Akuyi kubakho ncingo phantsi kwekristale ye-quartz naphantsi kwesixhobo esinovakalelo lwengxolo. Iwotshi, ibhasi kunye neempawu zokukhetha i-chip ziya kuba kude nomgca we-I / O kunye nesinxibelelanisi. Ungenelelo lwelayini yewotshi ejikeleze umgca we-I / O ungaphantsi kolo luhambelana nomgca we-I / O

(6) Isiphelo segalelo lesekethe engasetyenziswanga ayisayi kunqunyanyiswa, isiphelo esifanelekileyo sesixhobo sokukhulisa isixhobo esingasetyenziswanga siyakuba phantsi, kwaye isiphelo esingalunganga siya kudityaniswa kwisiphelo sesiphumo