RF PCB Board ukwakheka ukuze kuncishiswe amasiginali angamanga kudinga ubuhlakani bukanjiniyela we-RF.Ukugcina le mithetho eyisishiyagalombili engqondweni ngeke kusize nje ukusheshisa isikhathi ukuya emakethe, kodwa futhi kwandise ukuqagela kweshejuli yakho yomsebenzi.


Umthetho 1: Ama-vias aphansi kufanele abekwe kuswishi yendiza eyinkomba yaphansi
Wonke ama-currents ageleza emugqeni womzila anembuyiselo elinganayo.Kunamasu amaningi okuhlanganisa, kodwa ukugeleza okubuyayo kuvame ukugeleza ezindizeni eziseduze noma ezisekelweni ezibekwe ngokuhambisana nemigqa yesignali.Njengoba ungqimba lwereferensi luqhubeka, konke ukuhlanganisa kukhawulelwe kulayini wokudlulisela futhi yonke into isebenza kahle ngokuphelele.Kodwa-ke, uma umzila wesignali ushintshwa kusukela kungqimba olungaphezulu kuya kwengaphakathi noma ngaphansi, ukugeleza kokubuyisela kufanele futhi kuthole indlela.


Umfanekiso 1 uyisibonelo.Ngokushesha ngaphansi komugqa wesignali wezinga eliphezulu ukugeleza kokubuyisela.Uma idlulisela kungqimba olungezansi, ukugeleza kabusha kudlula nge-vias eseduze.Kodwa-ke, uma ingekho i-vias yokugeleza kabusha eduze, ukugeleza kabusha kuhamba endaweni eseduze etholakalayo nge.Amabanga amakhudlwana adala izihibe zamanje, enze ama-inductors.Uma lokhu kususwa kwendlela yamanje engafunwa kwenzeka ukweqa omunye umugqa, ukuphazamiseka kuzoba kubi kakhulu.Le loop yamanje empeleni ilingana nokwakha uthi!

Imithetho Eyisishagalombili Ezokusiza Ukwehlisa I-RF PCB Circuit Parasitics

Umfanekiso 1: Amandla esignali ageleza asuka kumaphini edivayisi adlulele kuzendlalelo eziphansi.Ukugeleza kabusha kungaphansi kwesignali ngaphambi kokuphoqelelwa ukuya eseduze ukuze kushintshele kusendlalelo esihlukile sereferensi

Ireferensi yaphansi iyisu elingcono kakhulu, kodwa imigqa enesivinini esikhulu ngezinye izikhathi ingafakwa ezendlalelo zangaphakathi.Ukubeka izindiza eziyinkomba eziphansi phezulu nangaphansi kunzima kakhulu, futhi abakhiqizi be-semiconductor bangase babambezeleke futhi babeke izintambo zikagesi eduze kwemigqa yesivinini esikhulu.Uma ireferensi yamanje idinga ukushintshwa phakathi kwezingqimba noma amanetha angahlangene ne-DC, ama-decoupling capacitor kufanele abekwe eduze kwendawo yokushintsha.



Umthetho 2: Xhuma iphedi yedivayisi endaweni ephezulu
Amadivayisi amaningi asebenzisa iphedi eliphansi elishisayo ngaphansi kwephakheji yedivayisi.Emishinini ye-RF, lezi ngokuvamile ziyizizathu zikagesi, futhi amaphuzu aseduze anoxhaxha lwama-vias angaphansi.Iphedi yedivayisi ingaxhunywa ngokuqondile kuphini eliphansi futhi ixhunywe kunoma yikuphi ukuthululwa kwethusi ngokusebenzisa ungqimba olungaphezulu lomhlabathi.Uma kunezindlela eziningi, ukugeleza kokubuyisela kuhlukaniswa ngokulingana ne-impedance yendlela.Ukuxhumana okuphansi ngephedi kunendlela emfushane nephansi ye-impedance kunenhlabathi yephini.


Ukuxhumana okuhle kukagesi phakathi kwebhodi namaphedi edivayisi kubalulekile.Ngesikhathi somhlangano, i-vias engagcwalisiwe ebhodini lesifunda nge-array ingaphinda ikhiphe unamathisele we-solder ocingweni, ishiye izikhala.Ukugcwalisa ngezimbobo kuyindlela enhle yokugcina i-solder isendaweni.Ngesikhathi sokuhlola, vula futhi isendlalelo semaski ye-solder ukuze uqinisekise ukuthi ayikho imaski ye-solder endaweni yebhodi ngezansi kwedivayisi, njengoba imaski ye-solder ingase iphakamise idivayisi noma ibangele ukuthi inyikinye.

Umthetho 3: Alikho Igebe Lesendlalelo Sezithenjwa

Kukhona ama-vias kuwo wonke umjikelezo wedivayisi.Amanethi kagesi ahlukaniswa ukuze anqanyulwe endaweni bese ehlela endizeni kagesi, ngokuvamile ahlinzeka ngezindlela eziningi zokunciphisa inductance futhi kuthuthukiswe umthamo wokuthwala wamanje, kuyilapho ibhasi elilawulayo lingaba phansi endizeni yangaphakathi.Konke lokhu kubola kugcina sekuboshwe ngokugcwele eduze kwedivayisi.


Ngayinye yalezi zindlela idala indawo engabaliwe endizeni yaphansi engaphakathi enkulu kunobubanzi be-via ngokwayo, ihlinzeka imvume yokukhiqiza.Lezi zindawo zokukhishwa zingabangela kalula iziphazamiso endleleni ebuyayo.Okunye okwenza isimo sibe nzima yiqiniso lokuthi amanye ama-vias asondelene futhi enza imisele yendiza yaphansi engabonakali ekubukeni kwe-CAD yezinga eliphezulu.Umfanekiso 2. Izikhala zendiza ephansi yezindiza ezimbili ezisebenza ngogesi zingadala izindawo ezigqagqene futhi zidale ukuphazamiseka endleleni ebuyayo.Ukugeleza kabusha kungaphambukiswa kuphela ukuze kudlule indawo enqatshelwe yendiza yaphansi, okuholela enkingeni yendlela yokungenisa ukukhishwa okujwayelekile.

Imithetho Eyisishagalombili Ezokusiza Ukwehlisa I-RF PCB Circuit Parasitics

Umfanekiso wesi-2: Izindawo zokugcina zezindiza ezingaphansi komhlaba ezizungeze i-vias zingase zidlulele, ziphoqelele ukubuya ukugeleza kude nomzila wesignali.Ngisho noma kungekho ukugqagqana, indawo yokungahambeki idala ukungaqhubeki kokulunywa yigundane endizeni yaphansi.

Ngisho nezindawo "ezinobungane" ziletha amaphedi ensimbi ahlobene nobukhulu obuncane obudingwa yi- ukukhiqizwa kwebhodi lesifunda eliphrintiwe inqubo.Ukuhamba eduze kakhulu nokulandela izimpawu kungase kubonakale ukuguguleka sengathi indawo ephansi yezinga eliphezulu ilunywe igundane.Umfanekiso 2 uwumdwebo wohlelo lokulunywa kwamagundane.


Njengoba indawo yokukhipha ikhiqizwa ngokuzenzakalelayo isofthiwe ye-CAD, futhi i-vias ivame ukusetshenziswa ebhodini lesistimu, cishe kuzohlale kukhona ukuphazamiseka kwendlela yokubuyisela phakathi nenqubo yokuhlela yasekuqaleni.Landela umugqa ngamunye onesivinini esikhulu phakathi nokuhlolwa kwesakhiwo futhi uhlole izendlalelo zokugeleza kabusha ezihambisanayo ukuze ugweme ukuphazamiseka.Kungumqondo omuhle ukubeka wonke ama-vias angakha ukuphazamiseka kwendiza yaphansi kunoma iyiphi indawo eseduze nendawo engenalutho yezinga eliphezulu.

Umthetho 4: Gcina Imigqa Ehlukile Ihlukile
Indlela yokubuya ibalulekile ekusebenzeni komugqa wesignali futhi kufanele ibhekwe njengengxenye yendlela yesiginali.Ngesikhathi esifanayo, amapheya ahlukile ngokuvamile awahlanganiswa ngokuqinile, futhi ukugeleza kokubuyisela kungase kugeleze ezendlalelo eziseduze.Zombili izimbuyiselo kufanele zihanjiswe ngezindlela ezilinganayo zikagesi.


Imikhawulo yedizayini yokusondelana nokwabelana igcina ukugeleza kokubuyisela kusendlalelo esifanayo ngisho nalapho imigqa emibili yokubhangqa okuhlukile ingahlanganiswa ngokuqinile.Ukuze ugcine amasiginali angamanga ephansi, ukufanisa okungcono kuyadingeka.Noma yiziphi izakhiwo ezihleliwe ezinjengama-cutouts ezindizeni eziphansi ngaphansi kwezingxenye ezihlukene kufanele zibe ne-symmetrical.Ngokufanayo, ubude obuhambisanayo bungadala izinkinga ngama-squiggles kumathrekhi wesignali.Ukugeleza kabusha akubangeli izinkinga zamagagasi.Ubude bokufanisa komugqa owodwa ohlukile kufanele kuboniswe kweminye imigqa ehlukene.

Umthetho 5: Alikho iwashi noma imigqa yokulawula eduze kwemigqa yesiginali ye-RF
Imigqa yewashi nokulawula kwesinye isikhathi ingabonakala njengomakhelwane abangabalulekile ngoba isebenza ngesivinini esiphansi, ngisho eduze ne-DC.Kodwa-ke, izici zayo zokushintsha cishe zingamagagasi ayisikwele, akhiqiza amathoni ahlukile kumaza angavamile we-harmonic.Imvamisa eyisisekelo yamandla aphumayo wegagasi lesikwele ayinandaba, kodwa imiphetho ebukhali ingabakhona.Ekwakhiweni kwesistimu yedijithali, imvamisa yekhona ingalinganisela i-harmonic yefrikhwensi ephezulu kakhulu okufanele icatshangelwe.Indlela yokubala ithi: Fknee=0.5/Tr, lapho i-Tr iyisikhathi sokukhuphuka.Qaphela ukuthi isikhathi sokukhuphuka, hhayi imvamisa yesignali.Kodwa-ke, amagagasi ayisikwele acijile aphinde abe nokuvumelana okuqinile kwe-oda eliphezulu okungahle ehle kuphela ngefrikhwensi engalungile bese abambhangqwana emugqeni we-RF, ephula izimfuneko eziqinile zamamaski.


Iwashi nemigqa yokulawula kufanele ihlukaniswe nemigqa yesignali ye-RF ngendiza yangaphakathi yaphansi noma ukuthela okusezingeni eliphezulu.Uma ukuhlukaniswa komhlaba kungeke kusetshenziswe, imikhondo kufanele ihanjiswe ngendlela ukuze iwele ngama-engeli angakwesokudla.Ngenxa yokuthi imigqa kazibuthe eguquguqukayo ekhishwa iwashi noma imigqa yokulawula izokwakha amakhontoyutha ekholomu akhazimulayo azungeze imisinga yemigqa yesiphazamisi, ngeke ikhiqize amaza kumigqa yomamukeli.Ukunciphisa isikhathi sokukhuphuka akunciphisi imvamisa yekhona kuphela kodwa futhi kusiza ukunciphisa ukuphazamiseka okuvela kubaphazamisi, kodwa iwashi noma imigqa yokulawula ingasebenza njengemigqa yomamukeli.Ulayini owamukelayo usasebenza njengomgudu wamasignali mbumbulu ocingweni.

Umthetho 6: Sebenzisa umhlabathi ukuze uhlukanise imigqa enesivinini esikhulu
Ama-Microstrip kanye nemigqa ehlutshiwe ngokuvamile ihlanganiswe nezindiza eziseduze.Eminye imigqa eguquguqukayo isaphuma ivundlile futhi inqamule imikhondo eseduze.Ithoni emugqeni owodwa wesivinini esikhulu noma ipheya ehlukile inqamuka ekulandeleni okulandelayo, kodwa ukugcwala komhlabathi kungqimba lwesignali kudala indawo ephansi yokunqamula i-impedance yolayini ogelezayo, kukhulula imikhondo eseduze kumathoni.

Amaqoqo okulandelela ahanjiswa ngokusabalalisa kwewashi noma idivayisi ye-synthesizer ukuze athwale imvamisa efanayo angase asebenze eduze kwamanye ngenxa yokuthi ithoni yesiphazamisi isivele ikhona emugqeni womamukeli.Kodwa-ke, imigqa eqoqwe ekugcineni izosabalala.Lapho kuhlakazwa, izikhukhula zaphansi kufanele zihlinzekwe phakathi kwemigqa ehlakazayo kanye nezindlela lapho iqala ukuhlakazeka khona ukuze ukubuyisela okudaliwe kugeleze kubuyele emuva ngendlela evamile yokubuya.Emfanekisweni wesi-3, ama-vias ekugcineni kweziqhingi eziphansi avumela amandla akhona ukuthi agelezele endizeni eyireferensi.Isikhala phakathi kwamanye ama-vias ku-perfusion yomhlabathi akufanele seqe ingxenye eyodwa kweshumi yobude begagasi ukuze kuqinisekiswe ukuthi umhlabathi awubi isakhiwo esinomsindo.

Imithetho Eyisishagalombili Yokukusiza Ukwehlisa I-RF I-PCB Circuit Parasitics

Umfanekiso 3: Indawo esezingeni eliphezulu lapho iminonjana ehlukene ihlakazekile inikeza izindlela zokugeleza zokugeleza okubuyayo.

Umthetho 7: Ungayihambisi imigqa ye-RF ezindizeni zamandla ezinomsindo
Ithoni ingena endizeni yamandla futhi isakazeka yonke indawo.Uma amathoni angamanga angena ezintweni zikagesi, amabhafa, izixube, ama-attenuators, nama-oscillator, angashintsha imvamisa ephazamisayo.Ngokunjalo, lapho amandla efika ebhodini, awakakhishwa ngokuphelele ukushayela i-RF circuitry.Ukuchayeka kwezintambo ze-RF ezindizeni zikagesi, ikakhulukazi ezindizeni zikagesi ezingahlungiwe, kufanele kuncishiswe.


Izindiza ezinkulu ezinamandla ezincikene nomhlabathi zenza ama-capacitor ashumekiwe ekhwalithi ephezulu anciphisa amasignali ezinambuzane futhi asetshenziswe ezinhlelweni zokuxhumana zedijithali nezinye izinhlelo ze-RF.Enye indlela ukusebenzisa izindiza zamandla ezincishisiwe, kwesinye isikhathi zifana nokulandela amafutha kunezendlalelo, ukuze kube lula ngemigqa ye-RF ukugwema izindiza zamandla ngokuphelele.Zombili izindlela zingenzeka, kodwa izici ezimbi kakhulu zazo zombili akumele zihlanganiswe, okuwukusebenzisa indiza encane yamandla nomzila wemigqa ye-RF phezulu.

Umthetho 8: Qhubeka nokuhlukanisa eduze nedivayisi
Ukuhlukanisa akusizi nje kuphela ukususa umsindo oyinkohliso kudivayisi, futhi kusiza ukususa amathoni akhiqizwe ngaphakathi kwedivayisi ukuthi angahlangani ezindizeni zikagesi.Lapho ama-decoupling capacitor esondela kumjikelezo osebenzayo, kuyanda ukusebenza kahle.Ukuhlukaniswa kwendawo akuphazanyiswa kancane yizithiyo zezinambuzane zokulandela umkhondo webhodi lesifunda, futhi imikhondo emifushane isekela izimpondo ezincane, kunciphisa ukukhishwa kwethoni okungafunwa.Ukubekwa kwe-Capacitor kuhlanganisa imvamisa ephakeme kakhulu yokuziphendulela, ngokuvamile inani elincane kakhulu, usayizi wekesi elincane kakhulu, eliseduze kakhulu nedivayisi, kanye ne-capacitor enkulu, eqhelelene kakhulu nedivayisi.Kumafrikhwensi e-RF, ama-capacitor angemuva kwebhodi adala ama-inductances e-parasitic wendlela esuka kwentambo ukuya emhlabathini, alahlekelwe inzuzo enkulu yokunciphisa umsindo.

Fingqa
Ngokuhlola ukwakheka kwebhodi, singathola izakhiwo ezingase zidlulise noma zithole amathoni e-RF angamanga.Landelela umugqa ngamunye, uhlonze ngokuqaphela indlela yawo ebuyayo, qiniseka ukuthi ungagijima ngokuhambisana nomugqa, futhi ikakhulukazi uhlole uguquko kahle.Futhi, hlukanisa imithombo engase ibe nokuphazamiseka komamukeli.Ukulandela imithetho ethile elula nenembile yokunciphisa amasiginali angamanga kungasheshisa ukukhululwa komkhiqizo futhi kunciphise izindleko zokususa iphutha.