Nyob rau hauv kev hloov pauv ntawm kev txawj ntse tsis tu ncua, automotive radar ua lub luag haujlwm tseem ceeb hauv kev nkag siab, ua cov haujlwm tseem ceeb xws li kev tshawb pom qhov deb, ntsuas qhov nrawm, thiab paub txog kev cuam tshuam.
millimeter-yoj siab-ceev PCBs, dhau los, ua raws li lub hauv paus platform kom ntseeg tau tias kev sib kis ruaj khov thiab ua tiav cov cim radar. Qhov txawv los ntawm lawv cov khoom siv tshwj xeeb, kev tswj cov txheej txheem meej, thiab kev ua tau zoo tshwj xeeb, cov PCBs no muab kev txhawb nqa zoo rau kev ua haujlwm zoo ntawm lub tsheb radar nyob rau hauv siab -frequency ib puag ncig, yog li tsav kev nce qib ntawm Advanced Driver-Assistance Systems (ADAS).
Automotive Radar millimeter-Wave High-Kev ceev PCBs
Cov yam ntxwv ntawm cov khoom tseem ceeb ntawm millimeter-Wave High-Speed PCBs
Lub millimeter-yoj zaus bands feem ntau siv nyob rau hauv tsheb radar yuam kom nruj cov ntaub ntawv PCB; tshwj xeeb, tsis tshua muaj teeb liab poob thiab kev ruaj ntseg siab yog qhov tseem ceeb rau kev xaiv cov khoom siv. Substrates haum rau millimeter-yoj siab-PCBs ceev yuav tsum muaj qhov tsis tshua muaj hluav taws xob tsis tu ncua (Dk) thiab qis dielectric poob tangent (Df). Cov piv txwv muaj xws li cov ntaub ntawv xws li PTFE thiab Rogers RO series. Cov ntaub ntawv no ua tau zoo txo qhov txo qis ntawm qhov siab - zaus cov cim thaum lub sij hawm kis tau tus mob, yog li ua kom cov teeb liab ncaj ncees. Tsis tas li ntawd, cov coefficient ntawm thermal expansion (CTE) ntawm cov ntaub ntawv yuav tsum tau sib npaug sib npaug -tshwj xeeb tshaj yog nyob rau hauv multi- txheej hybrid laminates, qhov twg CTE ntawm siab - zaus core txheej yuav tsum ua raws li cov ntaub ntawv sib txuas. Qhov kev sib raug zoo no tiv thaiv kev sib tsoo ntawm lub rooj tsavxwm los ntawm qhov kub thiab txias, uas tuaj yeem cuam tshuam qhov ruaj khov ntawm cov teeb liab kis tau tus mob. Tsis tas li ntawd, cov ntaub ntawv yuav tsum muaj cov thermal tiv thaiv zoo heev los tiv thaiv qhov kub ntawm qhov chaw ib puag ncig thaum lub sijhawm ua haujlwm ntawm lub tsheb, ua kom lub zog ruaj khov ntawm qhov kub thiab txias thiab ua kom muaj kev hloov pauv nyob rau hauv qhov tsawg kawg nkaus kam rau ua kom paub tseeb radar nrhiav kom raug. Hais txog kev ua tiav saum npoo, cov txheej txheem immersion kub yog qhov kev xaiv zoo tshaj plaws rau millimeter -yoj siab - ceev PCBs. Qhov kev nyiam no yog los ntawm cov tuab tuab thiab muaj zog adhesion ntawm txheej kub, uas tso cai rau impedance tsis raug tswj nyob rau hauv ± 5% thiab txo qis impedance fluctuations thaum kub hloov. Piv nrog rau lwm txoj kev ua tiav xws li Cov Cua Kub Kub Solder Leveling (HASL) lossis Organic Solderability Preservative (OSP), cov txheej txheem kub immersion txo qis cov teeb liab sib kis.
Yam tseem ceeb ntawm Precision Processing rau millimeter-Wave High-Speed PCBs
Kev tswj cov txheej txheem meej yog qhov tseem ceeb uas ua rau siab - kev ua tau zoo ntawm millimeter -yoj siab - ceev PCBs; qhov ua tiav ntawm txhua theem ncaj qha cuam tshuam qhov zoo ntawm cov teeb liab kis tau tus mob. Thaum lub sij hawm lamination thiab hybrid lamination theem, siab - cov ntaub ntawv zaus feem ntau muaj qhov nqaim qhov rais ua haujlwm. Yog li ntawd, lub siab yuav tsum tau siv sib npaug los tiv thaiv kev tsim cov voids (npuas) lossis "resin- tshaib plab" thaj chaw, yog li tsis txhob muaj qhov hloov pauv hauv cheeb tsam hauv dielectric tas li uas tuaj yeem cuam tshuam qhov sib xws ntawm cov teeb liab kis tau tus mob. Hauv ntau- txheej txheej, kev sib txuas ntawm qhov siab - cov txheej txheem ntau zaus thiab lwm cov ntaub ntawv tsim nyog yuav tsum muaj zog los xyuas kom muaj kev ruaj ntseg ntawm kev sib txuas ntawm cov txheej txheem sib txuas. Cov txheej txheem drilling thiab metallization xav tau siab precision; lub qhov phab ntsa roughness yuav tsum tau khaws cia nyob rau hauv ib tug tsawg heev ntau yam, qhov muag tsis pom qhov tob tolerances yuav tsum tau nruj me ntsis tswj, thiab rov qab-drilling qhov tseeb yuav tsum tau meej rau qib micron kom tsis txhob muaj cov seem seem los ntawm kev qhia parasitic inductance uas cuam tshuam cov teeb liab. Nyob rau hauv cov qauv hloov thiab etching theem, Direct Laser Imaging (DLI) thev naus laus zis tau dhau los ua tus qauv, ua kom muaj siab -kev tswj xyuas cov kab dav thiab qhov sib txawv; rau siab- cov khoom kawg, kab dav kam rau siab tuaj yeem ncav cuag ± 5μm. Tsis tas li ntawd, qhov sib txawv ntawm qhov sib txawv ntawm cov khub sib txawv yuav tsum tau khaws cia nyob rau hauv qhov tsawg kawg nkaus kom ntseeg tau tias theem sib txuam, thaum lub etching qhov tseem ceeb yuav tsum tau khaws cia rau hauv qhov tsim nyog los tiv thaiv impedance sib txawv los ntawm cov teeb meem nrog kab hla -section. Kev tswj hwm impedance nyob ntawm qhov tseem ceeb ntawm millimeter -yoj siab - ceev PCB fabrication. Los ntawm kev siv cov qauv tsim hybrid sib txuas nrog cov qauv microstrip thiab stripline-coupled nrog kev tswj meej ntawm kab dav thiab qhov sib nrug-impedance kam rau ua tau nyob rau hauv ± 5%, yog li inhibiting teeb liab kev xav thiab crosstalk kom ruaj ntseg teeb liab kis tau tus mob nyob rau hauv ntev.
Kev Ua Haujlwm Kev Ua Haujlwm thiab Electromagnetic Compatibility hauv millimeter-Wave High-Speed PCBs
Electromagnetic ib puag ncig nyob rau hauv lub tsheb yog complex; yog li ntawd, millimeter-yoj siab-ceev PCBs yuav tsum muaj qhov tshwj xeeb ntawm cov teeb liab kev ncaj ncees thiab electromagnetic compatibility los tiv thaiv cov teeb liab cuam tshuam thiab xyuas kom muaj kev ua haujlwm ntawm radar systems. Yuav kom ua tiav cov teeb liab kev ncaj ncees, PCBs yuav tsum siv cov kab sib txuas kom tsim nyog- xws li hauv av coplanar waveguides nyob rau hauv siab -frequency bands- uas, piv rau cov kab microstrip ib txwm muaj, muaj kev tswj hwm impedance zoo tshaj thiab txo cov teeb liab cuam tshuam thiab cuam tshuam. Kab ces kaum yuav tsum tau tsim nrog arcs los yog 45-degree kaum sab xis kom tsis txhob poob teeb liab cuam tshuam nrog txoj cai-lub kaum sab xis, thiab maj mam hloov yuav tsum tau ua hauj lwm thaum kab dav hloov los xyuas kom meej impedance txuas ntxiv. Ntawm kev tsim yuav tsum tau optimization; los ntawm kev tsim kho kom zoo los tiv thaiv-pads thiab av vias, impedance discontinuities tuaj yeem raug kaw rau qhov tsawg kawg nkaus, yog li txo qhov cuam tshuam ntawm cov kab mob parasitic. Hais txog electromagnetic compatibility, cov tswv yim xws li cov tswv yim kev tso kawm ntawm RF shielding enclosures thiab lub hwj huam mov filtering yog ua hauj lwm los thaiv cov intrusion ntawm sab nraud electromagnetic cuam tshuam thiab suppress tawm sab nraud hluav taws xob ntawm sab hauv cov teeb liab. Kev tiv thaiv hauv av ntawm cov ntaub thaiv npog yuav tsum tau khaws cia nyob rau theem qis kom ntseeg tau tias muaj kev tiv thaiv siab tiv thaiv lub suab nrov los ntawm cov khoom xws li lub cav; Tsis tas li ntawd, cov khoom siv lim dej ntawm cov khoom siv hluav taws xob tau zoo lim tawm cov suab nrov nrov, ua kom lub zog purity thiab muab lub zog ruaj khov ib puag ncig rau cov teeb liab kis.
Kev txhim kho txuas ntxiv ntawm millimeter-yoj siab- ceev PCB kev ua tau zoo ua rau kev txhim kho thev naus laus zis tsis tu ncua ntawm cov tsheb radar systems, yog li txhawb kev nce qib ntawm kev tsav tsheb ntse mus rau qhov siab tshiab. Tam sim no, siab -ceev millimeter-wave PCBs tau siv dav hauv automotive radar systems ua haujlwm nyob rau hauv ntau zaus xws li 77 GHz thiab 79 GHz. Cov PCBs no txhawb nqa ntau yam ntawm cov neeg tsav tsheb siab heev-kev pabcuam kev ua haujlwm- suav nrog kev tswj kev caij nkoj, tsis siv neeg nres thaum muaj xwm ceev, thiab txoj kab taug kev-thiab lawv qhov kev ua tau zoo ncaj qha txiav txim siab txog qhov ntsuas qhov ntsuas ntawm radar thiab qhov tseeb, yog li ua haujlwm tseem ceeb rau kev nyab xeeb ntawm lub tsheb. Raws li autonomous tsav tsheb thev naus laus zis txuas ntxiv mus, cov kev xav tau muab tso rau ntawm lub tsheb radar nrhiav kom tau muaj peev xwm nce ntxiv; yog li ntawd, siab -ceev millimeter-wave PCBs tau nce mus rau qhov siab dua, qis dua cov teeb liab poob, thiab ntau daim ntawv cog lus. Nyob rau hauv lub neej yav tom ntej, kev tsim precision yuav raug txhim kho ntxiv, nrog rau cov kev ntsuas xws li kab dav kev kam rau siab thiab impedance tswj tau ua kom zoo dua qub. Tsis tas li ntawd, cov ntaub ntawv tshawb fawb thiab kev tsim kho yuav tsom mus rau cov ntaub ntawv tshiab uas muaj kev poob qis dua thiab ruaj khov dua. Ib yam li ntawd, kev loj hlob mus rau ntau yam - txheej txheej thiab kev sib koom ua ke yuav txhawb nqa lub teeb liab ua lub peev xwm ntawm PCBs, muab kev txhawb nqa zoo rau lub tsheb radar systems kom ua tiav cov kev xav paub ntau ntxiv thiab txhawb nqa kev lag luam tsav tsheb ntse mus rau qhov siab tshiab.