Kev tswj hwm kev tswj hwm ntawm cov ntawv luam tawm hluav taws xob yog qhov tseem ceeb hauv qhov siab - ceev thiabhigh - zausDaim ntawv thov Circuit Court. Rau luam tawm Circuit Court board manufacturers, kom ua tau raws li cov qauv tsim nyog tsuas yog siv hluav taws xob tsis haum (EMC) thiab tag nrho kev ntseeg tau ntawm cov khoom.
Cov ntsiab lus yooj yim ntawm Kev Tswj Impedance
Dab tsi yog impedance?
Impedance (Z) yog tag nrho cov kev tsis kam ntawm tam sim no hauv AC Circuit Court, ntsuas hauv Ohms (ω). Nws muaj kev tiv thaiv (r) thiab reactance (x), uas cov tshuaj reactor ntxiv rau hauv cov kev ua kom zoo (xl) thiab muaj peev xwm (xc). Nyob rau hauv kis kab mob kab ke ntawm cov ntawv luam tawm hluav taws xob, tej kev cuam tshuam tsuas yog nyob ntawm cov qauv geometric ntawm cov teeb liab kev teeb tsa, dielectric cov ntaub ntawv, thiab zaus.
Vim li cas kev cuam tshuam tswj tsim nyog?
Rau luam tawm cov board tsim, lub ntsiab ntawm kev tsim kho kev tswj hwm yog los xyuas kom muaj kev ncaj ncees ntawm lub teeb liab kev sib kis, kom tau kev txhim kho kev ua yeeb yam thiab kev ruaj khov ntawm cov khoom siv hluav taws xob. Nyob rau hauv high - zaus 'zaus ntsuas kev sib kis, tsis sib haum xeeb yuav ua rau:
Kev nkag mus rau kev cuam tshuam thiab kev cuam tshuam cuam tshuam rau kev ntseeg tau ntawm qhov siab - ceev cov paib;
Nce EMI (electromagnetic cuam tshuam), cuam tshuam rau lub electromagnetic sib raug ntawm cov khoom;
Qhov nce ntawm cov ntaub ntawv yuam kev cuam tshuam rau kev ruaj ntseg ntawm kev sib txuas lus;
Lub teeb liab kev ua kom muaj zog, cuam tshuam rau kev ua tau zoo ntawm qhov ntev - deb kev kis
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Cov khoom siv xaiv rau high - zaus thiab siab {1} ceev luam tawm cov laug cam
Kev xaiv ntawm cov ntaub ntawv yog qhov tseem ceeb heev nyob rau hauv high - zaus thiab siab} ceev cov ntawv tso cai. Cov ntaub ntawv nquag thiab lawv cov yam ntxwv muaj raws li hauv qab no:
F4: Ib qho kev luam tawm cov khoom siv hluav taws xob cov khoom siv nrog tus nqi qis tab sis siab DK tus nqi, haum rau nruab nrab thiab qis {{}}} kev siv ceev.
Rogers 4350B: Tsawg DK, qis poob, haum rau 5g kev sib txuas lus, microwave, thiab lub tshuab radar.
Moj Hawb400: Tsawg Lawm Poob, Ruaj Ntseg DK tus nqi, haum rau high- Kev ntsuas kev kis tus mob.
Panasonic Megtron 6: Kev ntseeg siab, haum rau high- kev siv ceev xws li cov ntaub ntawv tawm thiab cov ntaub ntawv kho kho.
Cov ntsiab lus tseem ceeb cuam tshuam rau kev cuam tshuam hauv cov ntawv luam tawm Circuit Court tsim
Hauv cov ntawv luam tawm Circuit Court tsim cov txheej txheem, cov txheej txheem tuab, diching cov kab ke ua haujlwm ua ke, yog li cuam tshuam nrog cov cim kev ncaj ncees thiab kev ua haujlwm. Hauv qab no yog cov ncauj lus kom ntxaws ntxaws ntawm cov kev cuam tshuam ntawm cov kev lag luam hluav taws xob luam tawm.
1. Tus cawv ntawm cov hlau dav ntawm impedance
Qhov dav ntawm xaim txiav txim siab tus nqi impedance, thiab lub nqaim qhov dav, siab dua lub impedance; Tus dav dav dav, qis dua qhov kev xav. Thaum lub sij hawm tsim kev tsim khoom, cov hauv qab no yuav cuam tshuam rau cov hlau hlau kawg:
Etching txheej txheem: tom qab corrosion yuav ua rau muaj kev sib txawv tiag tiag, thiab them nyiaj yuav tsum tau tseg thaum tsim qauv.
Lithography Raug: Raug thiab Kev Loj Hlob cuam tshuam rau kab kev tswj tau zoo, thiabHD TSIBCov ntawv luam tawm hluav taws xob yog qhov tshwj xeeb.
Qhov cuam tshuam ntawm tooj liab thickness: cov tuab dua lub tooj liab txheej, qhov pom tau ntau dua ntawm cov sab corrosion, thiab yuav tsum tau them ntau dua los xyuas kom meej meej ruaj khov.
Qhov kev tsis kam lees tsis kam lees paub txog kev sib txuas lus tsis pub dhau 5%, tab sis siab}}} Cov ntaub ntawv sib txuas lus ceev no yuav xav tau cov kev tseev kom muaj, xws li 5%.
2. Cov cawv ntawm tooj liab tuab ntawm kev ua haujlwm
Tooj liab thickness (unit: oz, 1oz=35 μ m) cuam tshuam rau DC tsis kam thiab ua rau cov kab mob kis tau. Thicker Tooj Liab txo kev tiv taus thiab kuj txo qis cov impedance.
Tooj liab thickness nce, impedance txo qis: tsis kam thiab sib npaug inductance txo qis, ua rau txo qis ntawm impedance.
Kev cuam tshuam kev suav yuav tsum xav txog tooj liab tuab: Tus qauv tooj liab tuab yog feem ntau 0.5oz (1.5 μ m), thiab siab} Phaj Cov Khoom Siv Hluav Taws Xob yuav xav tau 3oz lossis tuab dua.
Electroplating cuam tshuam rau cov tuab ntawm sab nraud tooj liab txheej:} txheej txheem hluav taws xob yuav nce ntxiv rau kev ntsuas lub ntsej muag, thiab qhov no yuav tsum tau txiav txim siab thaum xam kev txwv.
3. Dielectric Thickness
Dielectric thickness yog hais txog qhov tuab ntawm cov rwb thaiv tsev txheej nruab nrab ntawm lub teeb liab txheej thiab cov txheej txheem hluav taws xob. Nws cuam tshuam ncaj qha rau kev faib tawm capibutions thiab imporance ntawm tus kis kis:
Qhov nce ntxiv hauv dielectric thickness ua rau muaj kev nce ntxiv ntawm txheej txheem: Ib qho kev ncua duas ib ce yuav ua rau lub teeb liab dielle, yog li kev txhim kho lub dav hlau.
Thickness sib txawv thaum chaw tsim khoom: Vim yog resin ntws thaum lub sij hawm lamination txheej txheem, tuab tiag tiag dielectricic thickness yuav raug tshem tawm tus nqi. Yog li ntawd, nws yog qhov tsim nyog yuav tsum tau tswj cov lamination txheej txheem los xyuas kom meej meej.
Cov teeb meem sib xws hauv multi - txheej board: rau siab}}}}} kev sib xyaw ntawm interlayer dielectric thickness yog qhov tseem ceeb heev. Yog hais tias cov tuab tuab yog qhov tsis ncaj, nws yuav ua rau muaj kev tsis sib xws hauv cov chaw sib txawv, cuam tshuam cov phiajcim kis.
4. Dielectric tas li
Tus dielectric tas mus li (DK) txiav txim siab qhov kev sib tham nrawm ntawm cov cim hauv dielectric ntaub ntawv. Cov nquag DK muaj nuj nqis rau cov ntawv luam tawm hluav taws xob board substrates yog raws li hauv qab no:
FR4 cov khoom siv fr4 Cov Khoom Siv: DK ≈ 4.2 ~ 4.7
Cov ntaub ntawv ceev ceev (xws li Rogers 4350B): DK ≈ 3.48
Ultra High zaus Microwave cov ntaub ntawv (xws li Taconic RF35): DK ≈ 3.5
Qhov cuam tshuam ntawm DK ntawm impedance yog manifested li:
Ntau dua DK txo cov impedance: nce DK nce dua capibutions capitaljected capacitance, yog li txo impedance.
Zaus vam khom ntawm DK: DK ntawm FR4 txo qis nrog kev nce ntau, thaum lub siab ruaj khov thiab haum rau siab- ceev tsim qauv.
DK kev sib xws hauv kev tsim khoom: kom ntseeg tau tias DK Ruaj Ruaj, xws li ± 0.02) thaum lub sij hawm ua lag luam kom tsis txhob cuam tshuam kev sib cav.
5. Hom kis tau
Qhov cuam tshuam ntawm ntau hom kis kab sib kis cov qauv ntawm kev cuam tshuam sib txawv, feem ntau yog suav nrog:
Microstrip Kab: Qhov teeb tsa teeb liab yog nyob ntawm txheej sab nraud, nrog cov txheej dielectric thiab av txheej hauv qab no. Kev yuam kev suav tau yooj yim, tab sis nws yog yooj yim cuam tshuam los ntawm lwm yam sab nraud xws li cov ntsej muag zoo li cov ntsej muag cuav.
Ribbon Kab: Qhov kev teeb tsa teeb tsa yog ib puag ncig ntawm ob txheej ntawm ib puag ncig kev sib txawv, ua rau nws haum zoo - cov ntawv thov siab.
Loolanar WaveGuide: Muaj av hlau nyob ib sab ntawm tus teeb liab kab los txhim kho cov nyhuv thaiv, tsim nyog rau RF thiab microwave cirroge.
Hauv kev tsim khoom lag luam, cov kab sib txawv sib txawv muaj cov sib txawv yuav tsum muaj rau kev siv cov khoom siv tau. Piv txwv li, cov kab txaij txaij yuav tsum tswj cov txheej tuab ntawm daim dielectric, thaum Coplanar WaveGuides yuav tsum tau sib nrug ntawm cov av thiab cov paib sib txuam kom ntseeg tau tias kev sib txuam tsis zoo.
6. Tus yam ntxwv ntawm kev kub taub hau npog
Hauv iTstrip kab qauv, muaj cov npog ntsej muag txheej tuaj yeem cuam tshuam rau dielectric tas li (dk {{{} effect) ntawm teeb liab kev sib tw, yog li cuam tshuam impedance:
Lub impedance ntawm cov ntawv luam tawm hluav taws xob muaj cov npog ntsej muag kub me ntsis vim tias lub teeb liab ncaj qha rau huab cua, thiab DK ntawm huab cua yog ≈ 1.
Lub impedance ntawm luam tawm cov boardcuit Coff board nrog sold npog lub ntsej muag yog feem ntau yog ntau dua li ntawm huab cua (DK ≈ 3.0), uas yuav txo qis qhov kev yuam kev tag nrho.
Txhawm rau txo cov kev cuam tshuam ntawm cov tawv nqaij tawv ntawm cov qauv hluav taws xob tsim nyog, muaj kev lees paub tshwj xeeb ntawm DK ntawm daim npog cev uas siv tau rau hauv kev txiav txim siab suav.
7. Interflayer dlhos qhov tseeb
Nyob rau hauv multi - txheej printered Circuit Court Board tsim, cov kev sib txawv ntawm cov txheej txheem sib txawv ntawm cov khaubncaws sab nraud pov thawj sib txawv tuaj yeem cuam tshuam kev cuam tshuam:
Kev sib txawv dhau zuj zus tuaj yeem cuam tshuam rau cov kev yuam kev ntawm cov kab txaij thiab cov khub sib txawv, ua rau muaj teeb meem ntawm cov teeb meem kev sib txawv.
Qhov Precision Alcision (hauv ± 25 μ μ μ tau siv nyob rau hauv high -}}}}}} ™ luam tawm Circuit Court tsim.
The use of advanced optical alignment technology (such as laser alignment) and X-ray detection equipment helps reduce interlayer deviation and ensure the accuracy of impedance control.
8. Etching txheej txheem tswj
Etching yog cov kauj ruam tseem ceeb hauv cov luam tawm hluav taws xob tsim, cuam tshuam rau kab kawg dav, thiab cov duab zoo
Undercut: nws txo cov kab kab muaj txiaj ntsig zoo, yog li nce impedance.
Linerar Optimization: Ua ntej Etching cov txheej txheem xws li v {}} cov kab uas tsis zoo thiab txhim kho cov paib kev ua haujlwm.