1. Ungakhetha kanjani PCB ibhodi?

Ukukhethwa kwebhodi le-PCB kufanele kuhlangabezane nezidingo zokuklanywa nokukhiqizwa kwesisindo kanye nezindleko zebhalansi phakathi. Izidingo zokuklama zifaka izingxenye zikagesi nezomshini. Lokhu kuvame ukubaluleka lapho kuklanywa amabhodi we-PCB ashesha kakhulu (amaza amakhulu kune-GHz). Isibonelo, i-fr-4 material evame ukusetshenziswa namuhla ingahle ingalungeli ngoba ukulahleka kwe-dielectric kuma-GHz amaningana kunomthelela omkhulu ekunciphisweni kwesiginali. Endabeni kagesi, naka ukulahleka kwe-dielectric njalo kanye ne-dielectric kumvamisa owenzelwe.

2. Ungakugwema kanjani ukuphazamiseka kwemvamisa ephezulu?

Umqondo oyisisekelo wokugwema ukuphazanyiswa kwemvamisa ephezulu ukunciphisa ukuphazanyiswa kwensimu ye-elektroni yesgnetic ephezulu, eyaziwa nangokuthi yiCrosstalk. Ungakhuphula ibanga phakathi kwesiginali esinejubane nesiginali ye-analog, noma engeza imikhondo yokuqapha phansi / ishunt kwisiginali ye-analog. Futhi naka umhlaba wedijithali ukuphazanyiswa komsindo womhlabathi.

3. Ungayixazulula kanjani inkinga yobuqotho besiginali ekwakhiweni kwejubane elikhulu?

Ubuqotho besiginali empeleni yindaba yokufaniswa kwe-impedance. Izici ezithinta ukufaniswa kwe-impedance zifaka ukwakheka komthombo wesiginali, impedance yokuphuma, impedance yesici sekhebula, isici sohlangothi lokulayisha, nokwakhiwa kwekhebula le-topology. Isixazululo * terminaTIon bese ulungisa topology yekhebula.

4. Ungayibona kanjani intambo yokuhlukanisa?

Ukuxhunywa kombhangqwana umehluko kunamaphuzu amabili okufanele uwanake. Okunye ukuthi ubude bemigqa emibili kufanele bube bude ngangokunokwenzeka, kanti okunye ukuthi ibanga eliphakathi kwemigqa emibili (enqunywe yi-impedance yomehluko) kufanele lihlale lihlala njalo, okungukuthi, ukugcina ngokufana. Kunezindlela ezimbili ezihambisanayo: enye ukuthi imigqa emibili isebenza ohlangothini olufanayo ngohlangothi, kanti enye ukuthi imigqa emibili isebenza ezingqimbeni ezimbili ezincikene nezendlalelo ezingaphezulu nezingezansi. Ngokuvamile, ukuqaliswa kwangaphambilini kohlangothi nohlangothi kuvame kakhulu.

5. Ungayibona kanjani i-wiring ehlukile yomugqa wesiginali yewashi ngesiginali esisodwa sokukhipha?

Ufuna ukusebenzisa i-wiring ehlukile kufanele kube ngumthombo wesiginali futhi ukuthola ukuphela nakho kuyisiginali yokuhlukanisa kunengqondo. Ngakho-ke akunakwenzeka ukusebenzisa i-wiring ehlukile yesiginali yewashi ngokukhipha okukodwa kuphela.

6. Ngabe ukumelana okuhambisanayo kungangezwa phakathi kwamaphara womugqa umehluko ekugcineni kokuthola?

Ukumelana okuhambisanayo phakathi kwemigqa emibili yokuhlukanisa ekugcineni okwamukelwayo kuvame ukungezwa, futhi inani layo kufanele lilingane nenani le-impedance umehluko. Ikhwalithi yesiginali izoba ngcono.

7. Kungani izintambo zombili ngazimbili kufanele zisondele futhi zihambisane?

Ukuxhunywa kwamabili ngazimbili kufanele kusondele ngokufanele futhi kufane. Ukuphakama okufanele kungenxa ye-impedance yomehluko, okuyipharamitha ebalulekile ekwakheni ngababili bomehluko. Ukufana futhi kuyadingeka ukugcina ukungaguquguquki kwe-impedance umehluko. Uma ngabe imigqa emibili ikude noma iseduze, i-impedance yokwehluka izobe ingahambelani, ethinta ubuqotho besiginali nokulibaziseka kwe-TIming.

8. Ungabhekana kanjani nezingxabano ezithile zethiyori entanjeni yangempela?

(1). Ngokuyisisekelo, kulungile ukuhlukanisa amamojula / izinombolo. Ukunakekelwa kufanele kwenziwe ukungaweli i-MOAT futhi ungavumeli ukunikezwa kwamandla nesiginali yokubuyisa indlela yamanje ikhule kakhulu.

(2). ICrystal oscillator iyisimo sokulinganisa impendulo esilingisayo esilingisayo, futhi amasiginali azinzileyo kufanele ahlangabezane nemininingwane yokutholwa kwe-loop nesigaba, esivame ukuphazanyiswa, noma imikhondo yokuqapha phansi ingahle ingakwazi ukuhlukanisa ngokuphelele ukuphazamiseka. Futhi ukude kakhulu, umsindo osendizeni yomhlaba uzophinde uthinte isekethe le-feedback oscillation. Ngakho-ke, qiniseka ukwenza i-crystal oscillator ne-chip zisondele ngangokunokwenzeka.

(3). Ngempela, kunezingxabano eziningi phakathi kwezidingo ze-wiring ezisheshayo nezidingo ze-EMI. Kodwa-ke, umthetho oyisisekelo ngukuthi ngenxa yamandla wokumelana noma iFerrite Bead engezwe yi-EMI, ezinye izici zikagesi zesiginali azinakubangelwa ukuthi zihluleke ukuhlangabezana nemininingwane ethile. Ngakho-ke, kungcono ukusebenzisa inqubo yokuhlela izintambo nokufakwa kwe-PCB ukuxazulula noma ukunciphisa izinkinga ze-EMI, njengokufakwa kwesiginali esisheshayo. Ekugcineni, kwasetshenziswa i-resistor capacitance noma indlela ye-Ferrite Bead ukunciphisa ukulimala kwesiginali.

9. Ungakuxazulula kanjani ukungqubuzana phakathi kwezintambo ezenziwe ngezandla kanye nokuxhunywa okuzenzakalelayo kwamasiginali asheshayo?

Kulezi zinsuku, iningi lamadivayisi we-cabling othomathikhi kwisoftware eqinile yokubeka ikhebula asethe izingqinamba zokulawula imodi ejiyile kanye nenani lezimbobo. Izinkampani ze-EDA kwesinye isikhathi ziyahlukahluka kakhulu ekubekeni amandla nezingqinamba zezinjini ezijikayo. Isibonelo, noma ngabe kukhona izingqinamba ezanele zokulawula ukuthi ulayini we-serpenTIne uvunguza kanjani, noma ngabe kukhona izingqinamba ezanele zokulawula izikhala zamabili ngomehluko, njll. Lokhu kuzothinta ukuthi ngabe izintambo ezizenzakalelayo eziphuma kuzintambo zingahambisana nombono womklami. Ngaphezu kwalokho, ubunzima bokulungiswa kwentambo mathupha nakho kuhlobene kakhulu nekhono lenjini egoqwayo. Isibonelo, amandla we-wire pushing, ngomgodi wokuxosha umgodi, ngisho nocingo ekuhlanganiseni kwethusi ukuphonsa amandla nokunye. Ngakho-ke, khetha ikhebula elinekhono elinamandla lenjini, kuyindlela yokuxazulula.

10. Mayelana nekhuphoni lokuhlola.

Ikhuphoni Lokuhlola lisetshenziselwa ukukala ukuthi ingabe i-impedance yesici yebhodi le-PCB elikhiqizwayo ihlangabezana yini nezidingo zokuklanywa ngokusebenzisa i-Time Domain Reflectometer (TDR). Ngokuvamile, impedance yokulawula ilayini elilodwa nokwehlukana kwamacala amabili. Ngakho-ke, ububanzi bomugqa nokuhlukaniswa kwemigqa (uma kwehlukile) Kukhuphoni Lokuhlola kufanele kufane nolayini olawulwayo. Into ebaluleke kakhulu indawo iphuzu isisekelo. Ukuze kuncishiswe inani lokungeniswa komthofu womhlaba, iphuzu lomhlabathi lesiphenyo se-TDR ngokuvamile lisondele kakhulu kunothi lesiphakamiso. Ngakho-ke, ibanga nendlela yokulinganisa iphuzu lesiginali nephoyinti lokuhlola kuKhuphoni lokuhlola kufanele lihambisane nephenyo esetshenzisiwe.

11. Ekwakheni i-PCB enejubane elikhulu, indawo engenalutho yesendlalelo sesiginali ingafakwa ithusi, nokuthi ungayisabalalisa kanjani ithusi ekufakeni phansi nasekuhlinzekelweni kwamandla kwezendlalelo zamasignali amaningi?

Ngokuvamile endaweni engenalutho ukumbozwa kwethusi iningi lamacala lisekiwe. Mane unake ibanga eliphakathi kwethusi nolayini wesiginali lapho kusetshenziswa ithusi eceleni kolayini wesiginali esinejubane elikhulu, ngoba ithusi elifakiwe lizonciphisa impedance yesici somugqa. Futhi qaphela ukuthi ungathinti i-impedance yesici sezinye izingqimba, njengakwakhiwa komugqa owakhiwe kabili.

12. Ngabe ulayini wesiginali ngenhla kwendiza yokuhambisa ugesi ungasetshenziswa ukubala impedance yesici usebenzisa imodeli yolayini be-microstrip? Ngabe isinali phakathi kokuphakelwa kwamandla nendiza yasemhlabeni lingabalwa kusetshenziswa imodeli yomugqa weribhoni?

Yebo, zombili indiza yamandla kanye nendiza yaphansi kufanele ibhekwe njengezindiza eziyizethenjwa lapho kubalwa impedance yesici. Isibonelo, ibhodi elinezendlalelo ezine: ungqimba ophezulu – ungqimba wamandla – umugqa – ungqimba ongezansi. Kulesi simo, imodeli yesici sokuncishiswa kwezintambo ezingaphezulu kwesendlalelo iyimodeli yolayini be-microstrip enamandla endiza njengendiza eyinkomba.

13. Ngabe amaphuzu wokuhlola angazenzakalela nge-software ekwi-high density PCB ahlangabezane nezidingo zokuhlolwa kokukhiqizwa kwenqwaba ngokujwayelekile?

Ukuthi amaphuzu okuhlola akhiqizwe ngokuzenzakalela yi-software ejwayelekile angahlangabezana nezidingo zokuhlola kuya ngokuthi izincazelo zamaphoyinti okuhlola angeziwe zihlangabezana yini nezidingo zomshini wokuhlola. Ngaphezu kwalokho, uma i-wiring iminyene kakhulu futhi imininingwane yokufaka amaphuzu okuhlola iqinile, kungenzeka ingakwazi ukwengeza ngokuzenzakalela amaphuzu okuhlola esigabeni ngasinye somugqa, kunjalo, udinga ukuqedela indawo yokuhlola ngesandla.

14. Ngabe ukwengezwa kwamaphuzu okuhlola kuzolithinta yini ikhwalithi yamasignali ashesha kakhulu?

Ukuthi kuthinta ikhwalithi yesiginali kuncike ekutheni amaphuzu okuhlola afakwa kanjani nokuthi isignali ishesha kangakanani. Ngokuyisisekelo, amaphuzu wokuhlola angeziwe (hhayi nge-pin noma nge-DIP njengamaphoyinti wokuhlola) angangezwa kulayini noma ukhishwe kulayini. Esokuqala silingana nokufaka i-capacitor encane kakhulu kulayini, eyokugcina iyigatsha elengeziwe. Zombili lezi zimo zombili zinethonya elingaphansi noma elingaphansi kumasiginali wejubane, futhi izinga lethonya lihlobene nesivinini semvamisa kanye nesilinganiso somphetho wesiginali. Ithonya lingatholakala ngokulingisa. Empeleni, lapho iphuzu lokuhlola lincane, iba ngcono (impela, ukuhlangabezana nezidingo zomshini wokuhlola) lapho lifushane igatsha, liba ngcono.

15. Inani le-PCB system, yokuxhuma kanjani umhlabathi phakathi kwamabhodi?

Lapho isignali noma ukunikezwa kwamandla phakathi kwebhodi ngalinye le-PCB kuxhunywe komunye nomunye, ngokwesibonelo, Ibhodi linokuphakelwa kwamandla noma isiginali ebhodini le-B, kufanele kube nenani elilinganayo lamanje kusuka ekugelezeni phansi kubuyele ku-A board (lena yi-Kirchoff umthetho wamanje). Okwamanje kulolu ungqimba kuzobuyela emuva ku-impedance ephansi kakhulu. Ngakho-ke, inani lezikhonkwane ezinikezwe ukwakheka akumele libe phansi kakhulu kusixhumi esibonakalayo ngasinye, kungaba amandla noma ukuxhumeka kwesiginali, ukunciphisa impedance futhi ngaleyo ndlela kunciphise umsindo wokwakheka. Kungenzeka futhi ukuhlaziya yonke iluphu yamanje, ikakhulukazi ingxenye enkulu yamanje, futhi ulungise ukuxhumana komhlaba noma umhlabathi ukulawula ukuhamba kwamanje (ngokwesibonelo, ukudala impedance ephansi endaweni eyodwa ukuze iningi kokugeleza kwamanje kuleyo ndawo), kunciphisa umthelela kwezinye izimpawu ezizwelayo.