Funda malunga newotshi kwi-PCB

Qaphela le miba ilandelayo yewotshi ebhodini:

1. Uyilo

a, ikristale iwotshi kunye neesekethe ezinxulumene kufuneka zicwangciswe kwindawo esembindini we-PCB kwaye ibe nokwakheka okulungileyo, kunokuba kufutshane ne-interface ye-I/O. Isekethe yokuvelisa iwashi ayinakwenziwa kwikhadi lentombi okanye ifom yebhodi yentombi, kufuneka yenziwe kwibhodi yewotshi eyahlukileyo okanye ibhodi yokuthwala.

Njengoko kuboniswe kulo mfanekiso ulandelayo, inxalenye yebhokisi eluhlaza yoluhlu olulandelayo ilungile ukuba ungahambi umgca

b, kuphela izixhobo ezinxulumene nokujikeleza kwewotshi kwindawo yesiphaluka sewashi ye-PCB, thintela ukubeka ezinye iisekethe, kwaye ungafaki ezinye iilayini zesignali kufuphi okanye ngaphantsi kwekristale: Ukusebenzisa indiza yomhlaba phantsi kwesekethe okanye ikristale eyenza iwashi, ukuba iimpawu zidlula kwi-plane, ephula umsebenzi wendiza yemephu, ukuba umqondiso udlula kwi-plane yomhlaba, kuya kuba ne-loop encinci yomhlaba kwaye kuthintele ukuqhubeka kwendiza yomhlaba, kwaye ezi zibhobho zomhlaba ziya kubangela iingxaki kwiifrikhwensi eziphezulu.

c. Kwiikristali zewashi kunye neesekethe zewashi, amanyathelo okukhusela angamkelwa ukusetyenzwa kokukhusela;

d, ukuba iqokobhe lewotshi liyintsimbi, uyilo lwePCB kufuneka lubekwe phantsi kobhedu lwekristale, kwaye uqinisekise ukuba le nxalenye kunye nenqwelomoya yomhlaba wonke inonxibelelwano oluhle lombane (ngokusebenzisa umhlaba omdaka).

Iingenelo zokugandaya phantsi kweekristale zewotshi:

Isekethe ngaphakathi kwekristali oscillator ivelisa iRF yangoku, kwaye ukuba ikristale ivalelwe kwindlu yentsimbi, iphini yamandla eDC kukuthembela kwereferensi yombane weDC kunye nereferensi ye-RF yangoku yelophu ngaphakathi kwekristale, ikhulula okwangoku okwenziwa Imitha ye-RF yezindlu ngenqwelomoya ephantsi. Ngamafutshane, iqokobhe lesinyithi yi-eriyali enesiphelo esinye, kwaye umaleko okufutshane womfanekiso, umaleko weplanethi esemhlabeni kwaye ngamanye amaxesha iileya ezimbini okanye ngaphezulu zanele ukudityaniswa kwe-radiative ye-RF yangoku emhlabeni. Umgangatho wekristale nawo ulungele ukutshabalalisa ubushushu. Umjikelo wewotshi kunye nekristale yangaphantsi iya kubonelela ngenqwelomoya, enokunciphisa indlela eqhelekileyo yangoku eveliswa yikristale kunye newotshi ehambelana nayo, ngaloo ndlela inciphisa imitha ye-RF. Inqwelomoya ephantsi nayo ifunxa imowudi yokwahluka kweRF yangoku. Le nqwelomoya kufuneka iqhagamshelwe kwinqwelomoya epheleleyo ngamanqaku amaninzi kwaye ifuna imingxunya emininzi, enokubonelela nge-impedance ephantsi. Ukuphucula umphumo wale nqwelomoya, i-clock generator circuit kufuneka isondele kule nqwelomoya.

Iikristale ezipakishwe yi-Smt ziya kuba nemitha yamandla e-RF ngaphezulu kuneekristale ezigqunywe ngentsimbi: Ngenxa yokuba iikristale ezibekwe phezu komhlaba ubukhulu becala ziziipakethe zeplastiki, i-RF yangoku ngaphakathi kwekristale iya kukhanya esithubeni kwaye idityaniswe nezinye izixhobo.

1. Yabelana ngendlela yewotshi

Kungcono ukudibanisa umqondiso wokunyuka ngokukhawuleza kunye nomqondiso wentsimbi kunye ne-radial topology kunokudibanisa inethiwekhi kunye nomthombo omnye womqhubi oqhelekileyo, kwaye umzila ngamnye kufuneka uhanjiswe ngokuphelisa amanyathelo ngokuhambelana ne-impedance yayo.

2, iimfuno zomgca wothumelo lwewotshi kunye nokubekwa kwePCB

Umgaqo womzila wewotshi: Lungiselela umaleko opheleleyo wendiza yomfanekiso kwindawo ekufutshane yomaleko wewotshi, unciphise ubude bomgca kwaye ulawule i-impedance.

Iingcingo ezingalunganga zomaleko onqamlezayo kunye nokungahambi kakuhle kwe-impedance kunokubangela:

I-1) Ukusetyenziswa kwemingxuma kunye nokuxhuma kwi-wiring kukhokelela ekunyameni kwe-loop yomfanekiso;

2) I-voltage yokunyuka kwinqwelomoya yomfanekiso ngenxa yombane kwiphini yomqondiso wesixhobo itshintsha ngokutshintsha kwesignali;

3), ukuba umgca awuqwalasele umgaqo we-3W, iimpawu zewashi ezahlukeneyo ziya kubangela i-crosstalk;

Iingcingo zesignali yewotshi

I-1, umgca wewotshi kufuneka uhambe kumaleko angaphakathi webhodi ye-PCB eninzi. Kwaye qiniseka ukuba ulandela umgca weribhoni; Ukuba ufuna ukuhamba kumaleko angaphandle, ngumgca we-microstrip kuphela.

I-2, umaleko wangaphakathi unokuqinisekisa inqwelomoya yomfanekiso opheleleyo, inokubonelela ngendlela yokuhanjiswa kwe-RF ephantsi-impedance, kwaye ivelise i-magnetic flux ukuphelisa i-flux yamagnetic yomgca wabo wokuhambisa umthombo, ngokusondeleyo umgama phakathi komthombo kunye nendlela yokubuya, ngcono ukucima. Enkosi kwi-demagnetization eyongeziweyo, umaleko ngamnye ogcweleyo weplani yomfanekiso wePCB enoxinano oluphezulu ubonelela ngoxinzelelo lwe-6-8dB.

I-3, iingenelo zebhodi ye-multi-layer: kukho i-layer okanye i-multiple layers inokunikezelwa kumandla apheleleyo kunye nenqwelomoya yomhlaba, inokuthi iqulunqwe ibe yinkqubo yokuqhawula kakuhle, ukunciphisa indawo ye-loop yomhlaba, ukunciphisa imo yokwahlukana. i-radiation, ukunciphisa i-EMI, ukunciphisa inqanaba le-impedance ye-signal kunye nendlela yokubuyisela amandla, inokugcina ukuhambelana kwayo yonke i-impedance yomgca, ukunciphisa i-crosstalk phakathi kwemigca esondeleyo.