Ukukhetha I-Substrate Elungile Ye-High Frequency PCB Design

Kungani I-Substrate Choice Ibalulekile Ekuklanyeni Okuphakeme Kwe-PCB

Ubuqotho Besiginali kanye Nethonya Lokubalulekile

I -substrate ye-PCB evame kakhulu inquma ngqo amapharamitha kagesi alawula ikhwalithi yesiginali. I-tangent yokulahlekelwa yi-dielectric ithinta ukulahlekelwa kokufakwa ngokusatshalaliswa kwamandla, kuyilapho ukubambezeleka kokusabalala kuyahlukahluka ngempande yesikwele ye-dielectric constant. Ukulawulwa kwe-impedance kuncike ezimpahleni ze-dielectric ezihambisanayo kulo lonke i-frequency spectrum, njengoba ngisho nokushintsha okuncane kwe-Dk kungashintsha i-impedance yesici ngama-ohms amaningana, kwehlisa amanethiwekhi afanayo futhi kubangele ukubonakaliswa.

Umehluko Phakathi Kwedizayini Yejubane Eliphezulu kanye Nemvamisa Ephakeme

Idizayini yedijithali enesivinini esikhulu igxile esilinganisweni sonqenqema kanye nokuphathwa kokuboniswa ngokulawulwa kokungaqhubeki kwe-impedance. Imvamisa ephezulu ye-RF kanye nesekhethi ye-microwave ibeka phambili ukuncishiswa kokufakwa kokulahlekelwa, ukuzinza kwesigaba, kanye nokungaguquki kwe-dielectric okulawulwayo kuwo wonke umkhawulokudonsa wokusebenza. Nakuba isixhumanisi sedijithali esingu-10 Gbps singase sibekezelele ukulahlekelwa kwe-substrate okumaphakathi, amalungu afanayo ahlukaniswe ngezigaba angu-28 GHz adinga izici zokulahla ngaphansi kuka-0.002 ukuze kugcinwe inzuzo eyamukelekayo nomsindo.

Izinselele Zomklamo Ezivamile

Ukukhethwa okungalungile kwe-substrate ye-PCB evame kakhulu kubonakala njengokulahlekelwa okukhulu kokufakwa okunciphisa isabelomali sesixhumanisi kanye nobubanzi besistimu. Ukukhukhuleka kwesigaba kanye nokushisa kudala amaphutha okuqondisa imisebe kuma-array ahlukaniswe ngezigaba kanye nokujiya kwesikhathi ezinhlelweni zokuthatha amasampula. Ukungafani kwe-impedance okuvela ezimpahleni ze-dielectric ezingazinzile kudala amagagasi amile anciphisa ukulahlekelwa kokubuya, kuyilapho izinto zokulahlekelwa okuphezulu ziguqula amandla esignali abe ukushisa, okubeka engcupheni ukusebenza kukagesi kanye nokuphathwa kokushisa. Lapho ukhetha ama-substrate e-AD300 amabhodi wesekethe ye-RF , qinisekisa ukuqokwa kwezinto eziqondile, ukujiya okutholakalayo kanye nendlela yokucubungula ngaphambi kokuvuma i-stackup.

Izinhlaka Ezibalulekile Zezinto Ezibalulekile Ze-High Frequency PCB Substrates

I-Dielectric Constant (Dk) kanye Nokuqina Kwayo Kwemvamisa

I-dielectric constant inquma i-geometry yomugqa wokudlulisela odingekayo ukuze kuzuzwe i-impedance eqondiwe. I-microstrip engu-50-ohm ku- Dk 3.5 into idinga izilinganiso ezihlukene zobubanzi nobude kune-impedance efanayo ku-Dkt 10 ceramic substrates. Izinto ezisetshenziswayo ze-Premium ephezulu ye-PCB substrate zicacisa ukubekezelela kuka-Dkt phakathi kuka-±0.05 nama-coefficients amafrikhwensi angaphansi kuka-50 ppm/GHz ukuze kuqinisekiswe ukusebenza okubikezelwe kusuka ku-DC ngokusebenzisa amaza ama-millimeter-wave.

I-Disipation Factor (i-Df noma i-Loss Tangent)

Isici sokulahla silinganisa ukulahlekelwa kwe-dielectric ngesilinganiso sokucatshangelwa kwezingxenye zemvume yangempela. Ku-10 GHz, i-substrate ene-Df ye-0.004 ibonisa cishe ukulahlekelwa kwe-dielectric kabili uma kuqhathaniswa nokokusebenza kwe-Df 0.002. Ama-substrates e-PCB emvamisa ephezulu yesimanje afinyelela izici zokulahla eziphansi njengo-0.0009 ezintweni ezisekelwe ku-PTFE, avumela amasekhethi amagagasi angamamilimitha anezabelomali zokulahlekelwa zokufaka ezamukelekayo.

Izakhiwo ezishisayo nezemishini

Amapharamitha ashisayo abalulekile wokuthembeka kwe-PCB substrate ephezulu kakhulu:

• Ukulinganisa kwe-CTE - I-coefficient engaphakathi kuka-5-10 ppm/°C yethusi ivimbela ukuqhekeka komgqomo ngokujikeleza kwamabhayisikili
• Izinga lokushisa lokushintsha kwengilazi – I-Tg engaphezu kuka-180°C imelana nokuhlanganiswa okunganomthofu okunemajini eyanele
• Ukuqhuba kwe-thermal - Amanani angaphezu kwe-1 W/mK anika amandla imiklamo yesikhulisi samandla ngaphandle kwezindawo ezishisayo
• Ukuzinza Thermal - Ipharamitha encane kagesi ikhukhuleka ku -40°C ukuya +125°C ibanga lokusebenza

I-Copper Surface Roughness kanye nokulahlekelwa kwe-Conductor

Kumafrikhwensi angaphezu kuka-5 GHz, umphumela wesikhumba ugxila okwamanje lapho iziqongo zokuma roughness zikhulisa ukumelana okusebenzayo kakhulu. I-electrodeposited copper evamile enobushelelezi be-RMS eyi-5-7 micrometer ingaphinda kabili ukulahleka kwe-conductor uma kuqhathaniswa namafoil abushelelezi angaphansi kwe-micrometer. Izinto ezisetshenziswayo ze-Premium high frequency PCB substrate zisebenzisa ama-foil ahlanekezelwa ukuze kuncishiswe lo mphumela, njengezikali zesijeziso esinobugwegwe esinomsuka oyisikwele wemvamisa.

Uhlolojikelele lwezinto ezisetshenziswayo ze-Common High Frequency PCB Substrate

I-PTFE (Teflon) kanye ne-Ceramic-Filled PTFE

Ama-substrate e-PTFE amsulwa aletha izici zokusaphazeka eziphansi kakhulu cishe ku-0.0010 kanye nokuzinza okuhle kakhulu kwe-dielectric kuwo wonke amazinga okushisa kanye nemvamisa. Ama-filler e-ceramic aguqula i-dielectric constant kusuka ku-2.1 ye-PTFE yemvelo kuya kumanani aklanywe phakathi kuka-2.2 no-10.2, okwenza kube lula ukuklama i-impedance elawulwayo. Lezi zinto zivelele ezinhlelweni zokusebenza zamagagasi e-millimeter kufaka phakathi ama-transceivers esathelayithi, amamojula e-radar, kanye nama-antenna e-5G amakhulu e-MIMO.

Rogers RO4000 / RO4350B Uchungechunge

Umndeni we-RO4000 usebenzisa ama-laminate e-hydrocarbon-ceramic agcina ukuhambisana nemishini yokucubungula ye-FR-4 ejwayelekile. I-RO4350B ifinyelela ku-Dk engu-3.48 nge-dissipation factor ecishe ibe ngu-0.0037 ku-10 GHz, okuletha ukusebenza okungcono kakhulu kune-FR-4 ethuthukisiwe. Lokhu kulinganisela kwenza kube yi-substrate ye-PCB evame kakhulu ekhethwayo yeziteshi zesisekelo ze-5G, i-radar yezimoto, kanye nezinhlelo zokusebenza ze-backplane ezinesivinini esikhulu ezidinga ubunzima bezingqimba eziningi.

I-Ceramic-based and Hydrocarbon-Ceramic Laminates

Izisekelo ze-ceramic ze- Alumina ne -aluminium nitride zinikeza ukuhanjiswa kokushisa okungaphezu kuka-20 W/mK kanye nama-dielectric constants asuka ku-9 kuya ku-10, afanelekela ama-amplifiers e-RF anamandla aphezulu. Ama-composites e-hydrocarbon-ceramic anikeza izixazululo eziphakathi nendawo ezinokuhanjiswa kokushisa okuzungeze u-0.6-0.8 W/mK, okwanele ubuningi bamandla obuphakathi. Lezi zinketho ze-substrate ze-PCB ezivame kakhulu zivumela ukwakheka okuhlangene ngenkathi kulawulwa ukusatshalaliswa kokushisa kuzinhlelo zokusebenza ze-amplifier yamandla.

I-Modified Epoxy ne-Hydrocarbon Materials

I-Panasonic Megtron 6 kanye nezinto ezifanayo ezisekelwe ku-hydrocarbon zithola izici zokusaphazeka cishe ku-0.002-0.004 ku-10 GHz ngokusebenzisa ubunjiniyela be-polymer. Lezi zingxenye zikhonza izinhlelo zokusebenza ze-PCB ezisezingeni eliphakathi nendawo kusukela ku-2 kuya ku-20 GHz lapho ukuzwela kwezindleko kuvimbela izixazululo ze-PTFE ezihlanzekile kodwa izidingo zokusebenza zidlula amakhono e-FR-4. Zihambisana nokucubungula okujwayelekile kwezingqimba eziningi, zifanelana nokuxhumeka kwesikhungo sedatha kanye namamojula we-radar yezimoto.

Izinhlobo ezithuthukisiwe ze-FR-4 kanye ne-High-Tg FR-4

Izici ezijwayelekile zokusatshalaliswa kwe -FR-4 eziseduze no-0.020 ku-1 GHz zikhawulela i-bandwidth esebenzisekayo ibe ngaphansi kwe-3 GHz yezindlela ezibalulekile zesignali. Izinhlobo ze-High-Tg ezinezinhlelo ze-resin ezithuthukisiwe zinciphisa i-Df ibe ngu-0.010-0.015 ububanzi, zandisa imvamisa ewusizo ibe ngu-5-6 GHz. I-FR-4 ethuthukisiwe isebenza njengezinto ezamukelekayo ze-PCB substrate ezivame kakhulu zokusatshalaliswa kwewashi kanye nezixhumi zememori lapho kubusa khona imikhawulo yezindleko.

Ithebula lokuqhathanisa: Izakhiwo ze-Dielectric kanye Nokulahlekelwa

Inqubo Esebenzayo Yokukhetha I-PCB Substrate Esebenza Kakhulu

Isinyathelo 1 - Chaza Imvamisa Yokusebenza kanye Nomkhawulokudonsa

Khomba ingxenye yefrikhwensi ephezulu kakhulu kububanzi besiginali yakho, kungakhathaliseki ukuthi imvamisa yenkampani yenethiwekhi eyisisekelo kumasekhethi e-RF noma i-harmonic ebaluleke kakhulu emiklamo yedijithali. I-oscillator yendawo engu-10 GHz idinga ukuhlolwa kwe-substrate ku-10 GHz, kuyilapho isignali engu-10 Gbps ye-NRZ idinga ukucaciswa kwezinto ezibonakalayo nge-harmonic yesihlanu eduze no-25 GHz. Le ncazelo yemvamisa iqeda ngokushesha izinto ezingafaneleki.

Isinyathelo sesi-2 - Hlola Ukulahleka Kwesiginali kanye Nokuqina Kwe-Dielectric

Sungula amabhajethi okulahlekelwa okufakwayo ngokunikeza ukuncishiswa okwamukelekayo ngaphakathi kokuhlaziywa kwebhajethi yesixhumanisi sakho. Izinto ezisetshenziswayo ze-PCB ezinefrikhwensi ephezulu ene-Df engaphansi kuka-0.002 zidingeka lapho ukulahlekelwa okuphelele kwe-dielectric kufanele kuhlale ngaphansi kuka-0.5 dB ekulandeleleni okungamayintshi angu-10 ku-28 GHz. Izicelo ezidinga okungcono kuno--20 dB ukulahlekelwa ukubuya zidinga ama-substrates ano-Dkt azinza ngaphakathi ±2% kuwo wonke amazinga okushisa nokubanda.

Isinyathelo sesi-3 - Cabangela Ukuphathwa Kokushisa kanye Nokuphatha Amandla

Izikhulisamandla zikagesi ezihlakaza ngaphezu kwama-watts angu-5 iyintshi yesikwele ngayinye zidinga imvamisa ephezulu ye-PCB substrate impahla enokuhanjiswa okushisayo okudlula i-1 W/mK noma izakhiwo ezisekelwa insimbi. Bala ukukhuphuka kwezinga lokushisa lendawo ehlanganayo uqinisekise ukuthi amamajini e-Tg amukela izimo zokusebenza ezimbi kakhulu. Amadizayini aminyene edijithali angase akhiqize ukushisa okwanele okucatshangelwayo okushisayo okudlula amamethrikhi okusebenza kagesi amsulwa.

Isinyathelo sesi-4 - Hlola Ukukhiqiza kanye Nezingqinamba Zezindleko

Ukucatshangelwa kokukhiqiza kokukhetha i-PCB substrate yemvamisa ephezulu:

• Ukuhambisana kwenqubo - I-PTFE idinga ukubhoboza okukhethekile kanye nomzila ngokumelene nokucubungula okujwayelekile kwe-RO4000
• Ukutholakala komhlinzeki - Ama-Premium substrates akhawulela izinketho zomkhiqizi futhi andisa izikhathi zokuhola
• Ubunkimbinkimbi bomklamo - Izitaki eziningi kanye nokubekezelelana okuqinile kufuna ozakwethu bokukhiqiza abanolwazi
• Amakhono esici - Ububanzi bokulandela umkhondo obuncane, nge-aspect ratios, nokubalwa kwesendlalelo kuyahluka ngohlobo lwezinto ezibonakalayo

Izimo zesibonelo: I-Millimeter-Wave vs High-Speed ​​Digital

I-antenna enezigaba engu-28 GHz idinga i-PTFE egcwele i-ceramic ene-Dk 3.0 ne-Df ngezansi kuka-0.0015 ukuze kuncishiswe ukulahleka kokufakwa kwenethiwekhi, lapho ukuthuthukiswa ngakunye okungu-0.1 dB kuthuthukisa ngokuqondile ububanzi bamalungu afanayo. Indiza engemuva engu-56 Gbps PAM-4 ibekezelela ukulahleka okuphakeme okuzungeze u-0.004, okwenza i-Rogers RO4350B noma i-Megtron 7 isebenze ukukhetha kwe-PCB substrate yefrikhwensi ephezulu yokulinganisa ukusebenza kukagesi nokwenziwa kwezendlalelo eziningi.

Ukucatshangelwa Kokuklama Nokukhiqiza kwama-PCB Substrates Emvamisa Ephakeme

Ukulawula Impedans kanye Nokuthuthukisa Ukupakisha

Ukufinyelela ukubekezelelana kwe-impedance okungu-±10% kudinga ukulawulwa okunembile kobukhulu be-dielectric, isisindo sethusi, kanye ne-trace geometry. Izinto ze-substrate ze-PCB ezivame kakhulu ezinemininingwane eqinile ye-Dk zivumela ukubalwa kwe-impedance okubikezelwayo, kodwa amanani angempela ancike ekulinganisweni kwe-stackup, ukugeleza kwe-prepreg ngesikhathi se-lamination, kanye nokufana kwe-copper plating. Sebenzisa i-differential signaling yezindlela ezibalulekile futhi ugcine ukujiya kwezingqimba ze-dielectric okuhambisanayo ngaphakathi kuka-±10%. Ukuze kwakhiwe i-thin-core RO4835T RF , ukuphathwa, i-lamination kanye nobukhulu be-dielectric obuqediwe kufanele kubuyekezwe ndawonye ngaphambi kokuba isakhiwo se-multilayer sivunyelwe.

I-Surface Finish kanye Nokukhethwa kwe-Copper Foil

Igolide lokucwiliswa kwe-nickel elingenawo ugesi lethula ukulahlekelwa okuncane kokufakwayo kodwa linikeza impilo yeshalofu elihle kakhulu kanye nokuhambisana kwentambo yokubopha. Isiliva lokucwiliswa kanye ne-organic solderability preservative kunciphisa ukulahlekelwa okwengeziwe kuyilapho kudinga ukuphathwa ngokucophelela. Cacisa i-foil ehlanekezelwe emuva noma ikhopha yephrofayili ephansi kakhulu kumafrikhwensi angaphezu kuka-10 GHz, lapho ubuhwaba obujwayelekile obufakwe ku-electrodeposited bethula ukulahlekelwa okwengeziwe okungu-20-40%.

Nge-Design and Transition Management

Izimbobo ezifakwe ngaphakathi zidala ukungaqhubeki kwe-impedance kusuka ekulayishweni kwephedi ye-capacitive kanye nemiphumela yemiphongolo engenisayo. Nciphisa ngokusebenzisa imithelela ngokubhoboza emuva ukuze ususe ama-stubs angasetshenzisiwe, noma sebenzisa izimbobo ezingaboni noma ezigqitshiwe ukuze uqede ngokuphelele izigaxa zembobo. Gcoba ngezithango ezihlukaniswe ngaphansi kwe-wavelength yamashumi amabili nanye kuvimbela ukukhala kwepuleti elihambisanayo kuzitaki ze-PCB ze-substrate eziyimvamisa ephezulu.

Izindlela Zokulinganisa Nokuqinisekisa

Izindlela zokuqinisekisa ezibalulekile zokusebenza kwe-substrate ye-PCB eyimvamisa ephezulu:

• Ukuhlaziywa kwepharamitha ye-S - Izilinganiso zenethiwekhi yeVector ziqinisekisa ukulahlekelwa kokufaka, ukulahlekelwa kokubuyisela, kanye nomugqa wesigaba
• Isikhathi-yesizinda reflectometry - Ihlonza ukungaqhubeki kwe-impedance ezindaweni ezithile ezibonakalayo
• Ukuhamba ngebhayisikili okushisayo - Imijikelezo engu-500-1000 ephakathi kuka -40°C kanye +125°C iqinisekisa ukwethembeka ngokusebenzisa ukuqapha ukumelana
• Ukulinganisa kwe-Dielectric - Izilinganiso ze-split-post resonator ziqinisekisa u-Dk kanye ne-Df yamabhodi akhiwe

Ukulinganisa Ukusebenza, Izindleko, Nokwenziwa

Ukuhwebelana Phakathi Kwezindleko Zokusebenza Kagesi Nezindleko Zokucubungula

Izinto ezisetshenziswayo ze-PCB ezinemvamisa ephansi kakhulu zithethelela inkokhelo yazo yezindleko ezingu-3-5× uma ukulahlekelwa kokufakwa kukhawulela ngokuqondile ububanzi besistimu, isilinganiso sedatha, noma ukusebenza kahle kwamandla. Ubude bokulandelela obufushane obungaphansi kwamayintshi angu-2 namafrikhwensi angaphansi kuka-10 GHz kuvame ukuzuza ukucaciswa ngezinto ezisetshenziswayo ezimaphakathi nesigaba ezibiza uhhafu kakhulu. Linganisa isiphakamiso senani ngokubala umthelela wezinga lesistimu kunokuthuthukisa izindleko zengxenye ngokuzihlukanisa.

I-Supply Chain kanye Nezici Zokutholakala

Okukhethekile okukhethekile okuphezulu kwe-PCB substrate ngezinye izikhathi kubhekana nezingqinamba zokwabiwa ngesikhathi sokuphazamiseka kokunikezwa. Ukucaciswa kwezinto ezibonakalayo okunemithombo emibili lapho ukusebenza kukagesi kuvumela, kufaneleka kokubili okunye okuhlukile kwe-Rogers ne-Taconic noma izinketho ze-Megtron ne-Isola ukuze kugcinwe ukuguquguquka kokukhiqiza. Izinhlelo zokukhiqiza zesikhathi eside ziyazuza ekusebenzisaneni kusenesikhathi nabasabalalisi bezinto ezibonakalayo ukuze kuvikelwe ukwabiwa kwamandla kanye nokuxoxisana ngenani lentengo.

Idizayini Esebenzisanayo noMkhiqizi we-PCB

Bandakanya ozakwethu bokukhiqiza ngesikhathi sokukhetha izinto kanye nencazelo ye-stackup kunokuqeda imiklamo yodwa. Abakhiqizi abanolwazi banikeza isiqondiso sokuklama ukukhiqiza ngobukhulu bezici obuncane, ngokusebenzisa izilinganiso zesici, kanye nokubekezelelana kwe-impedance okufinyelelekayo ngezinto ezithile ze-PCB substrate ezivame kakhulu. Cela amakhuphoni okuhlola i-impedance kanye namasampula okuchaza izinto ekuqaleni kokwenza i-prototyping ukuqinisekisa amamodeli kagesi. Phatha ibanga le-laminate elikhethiwe kanye nobukhulu be-dielectric ku -RF PCB quotation ethile yezinto ukuze ukuthengwa kuhlole ukwakhiwa okuqinisekiswe umklamo wakho.

Isifinyezo kanye Nenkomba esheshayo

I-Frequency Range vs Ithebula Lezinto Ezinconyiwe

Okubalulekile Okuthathwayo Abaklami

Ukukhethwa okuphumelelayo kwe-PCB substrate yefrikhwensi ephezulu kubeka phambili ukuguquguquka kwe-dielectric okuzinzile kulo lonke izinga lokushisa kanye nemvamisa, kunciphisa isici sokulahla ukuze kugcinwe ubuqotho besignali, futhi kuqinisekisa izakhiwo ezishisayo zisekela ukusebenza okuthembekile. Qondanisa amandla wezinto ezibonakalayo nezimfuneko zenqubo yokukhiqiza kusenesikhathi emijikelezweni yokuklama, ngokuqaphela ukuthi ukusebenza kahle kukagesi kudinga izinzuzo zokwenziwa ezitholakalayo. Qinisekisa ukucabangela ngokusebenzisa i-prototyping nokulinganisa kunokuthembela ekulingiseni kuphela.

Ukusebenzisana noMkhiqizi Ochwepheshe we-PCB

Ukukhethwa kanye nokusetshenziswa kwe-substrate ye-PCB evame kakhulu kuzuza kakhulu ngobuchwepheshe bomkhiqizi ekuphatheni izinto, ukwenza ngcono izinqubo, kanye nokuqinisekiswa kokuhlolwa. I-Highleap Electronics igxile ekwenziweni kwe-PCB evame kakhulu kuzo zonke izinhlelo ze-Rogers, Taconic, kanye ne-laminate ezithuthukisiwe, inikeza ukubonisana ngokuklama, ukukhiqizwa kwe-impedance elawulwayo, kanye nokuhlolwa kukagesi okuphelele.

Ithimba lethu lonjiniyela lisebenzisana nabaklami ukuze lenze izitaki, lifanelekele izinto zokwakha, futhi lisungule izinqubo zokukhiqiza eziletha imiphumela engaguquki kusuka ku-prototype ngamavolumu okukhiqiza.