Feem ntau hais lus, qhov cuam tshuam uas cuam tshuam rau tus xeeb ceem ntawm PCB yog: dienic thickness t, liyrctric tas li er ntawm cov khoom xaiv rau pawg xaiv rau cov duab, thiab tuab ntawm daim npog qhov ncauj.
Feem ntau, qhov ntau dua cov ntaub tuab dienectric thiab kab sib nrug, ntau dua tus nqi impedance; Qhov ntau dua dityectric tas li, tooj liab thickness, kab dav, thiab cov npog ntsej muag tuab, tus me dua tus nqi impedance.
Thawj tus: nruab nrab tuab, nce qhov nruab nrab tuab tuaj yeem nce cov impedance, thiab txo qhov nruab nrab tuab tuaj yeem txo qhov kev xav; Txawv cov khoom sib txawv muaj cov kua nplaum sib txawv thiab cov thicknesses. Lub thickness tom qab nias yog cuam tshuam nrog lub tiaj tiaj ntawm cov xovxwm thiab tus txheej txheem ntawm lub phaj nias; Rau txhua hom phaj siv, nws yog ib qho tsim nyog kom tau txais cov tuab ntawm cov xov xwm tshaj tawm, uas yog qhov tsim nyog los tsim cov kev daws teeb meem yog tus yuam sij rau xov xwm tuab tswj.
Qhov thib ob: kab dav, ntxiv rau txoj kab dav tuaj yeem txo qhov kev cuam tshuam, txo cov kab dav tuaj yeem nce impedance. Kev tswj hwm ntawm kab dav yuav tsum tau nyob hauv kev tiv thaiv ntawm +/- 10% kom ua tiav kev tswj hwm kev xav. Qhov sib txawv ntawm cov paib kab cuam tshuam rau tag nrho cov kev ntsuam xyuas waveForm. Nws ib-taw tes impedance yog siab, ua tag nrho cov kev xav tsis sib xws, thiab cov kab uas tsis tuaj yeem tso cai ua kab, qhov sib txawv tsis pub dhau 10%. Txoj kab dav yog feem ntau tswj los ntawm kev tswj etching. Txhawm rau kom ntseeg tau tias kab dav, raws li cov khoom siv etching etching, thiab cov txheej txheem kos duab yuam kev, thiab cov txheej txheem kos duab raug them rau cov txheej txheem kom tau raws li txoj kab yuav tsum tau ua.
Qhov thib peb: tooj liab tuab, txo txoj kab tuab tuaj yeem nce cov impedance, nce cov kab thickness tuaj yeem txo qhov kev xav; Kab thickness tuaj yeem tswj los ntawm cov qauv plating lossis xaiv cov kev coj ua tuab ntawm cov khoom siv tooj liab. Kev tswj hwm ntawm tooj liab tuab yog yuav tsum tau hnav khaub ncaws. Ib lub shunt thaiv yog ntxiv rau lub rooj tsavxwm ntawm nyias cov xov hlau thiab cais cov xov tooj ntawm cov xaim hluav taws xob tsis zoo rau cov tooj liab ntawm CS thiab SS SURFACES. Nws yog ib qho tsim nyog los hla lub rooj tsavxwm kom ua tiav lub hom phiaj ntawm cov khoom siv tooj liab tuab ntawm ob sab.
Qhov thib plaub: dielectric tas li, nce cov dienectric tas li tuaj yeem txo qhov kev cuam tshuam, ua rau lub cev tsis tu ncua, tuaj yeem tswj tau tsuas yog tswj tau los ntawm cov khoom siv. Lub dielectric constant ntawm cov phaj txawv txawv yog sib txawv, uas yog dielectric conventent ntawm FR4 phaj yuav tsum muaj txiaj ntsig zoo, uas yuav tsum muaj cov khoom siv tsis tu ncua.
Qhov thib tsib: cov tuab ntawm daim npog qhov ncauj. Luam Ntawv Daim Npog Tawv Yuav Txo Cov Me Nyuam Yuav Txo Cov Tsis kam ntawm cov txheej txheej sab nraud. Nyob rau hauv ib txwm muaj xwm txheej, luam ntawv ib daim npog ntsej muag nkaus xwb tuaj yeem txo tau ib leeg-Ohms, thiab tuaj yeem ua rau cov qib siab poob los ntawm 8 ohms. Luam ntawv ob zaug tus nqi poob yog ob zaug ntawm ib pass. Thaum luam ntawv ntau dua peb zaug, tus nqi impedance yuav tsis hloov.