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ceramic capacitors

Cov txheej txheem cej luam, cov ntaub ntawv lossis kev qhia txog cov qauv tseem ceeb ntawm koj cov tais hluav taws xob (ceramic capacitor): nws txoj kev ua haujlwm, cov ntaub ntawv ua haujlwm, cov khoom sib txuas ntxiv rau kev ua haujlwm hauv cov ceramic capacitor.

Ntau yam Capacitor cuam tshuam nrog:

* Capacitor hom lus txheej txheem cej luam

* Siv thiab cov ntawv thov

* Kev Siv Lub Tshuab Hluav Taws Xob

* Tej hub capacitor

* Tantalum capacitor

* Polycarbonate capacitor

* Nyiaj mica capacitor

* Iav dielectric capacitor

* Polystyrene capacitor

Tej hub capacitors yog ib tus neeg ntawm koj qhov kev siv ntau hom capacitor siv hauv cov khoom siv hluav taws xob niaj hnub no. Ceramic capacitors kuj tau thov rau ob peb xyoo lawm, tam sim no tau tam sim no nyob rau hauv cov kev sib txuas valve lossis lub raj kab hluav taws xob los ntawm koj 1930s.

Tam sim no tej hub capacitors hnov ​​tau nyob rau hauv ntau hom qauv ntau yam los ntawm leaded ntsiab rau saum npoo mount engineering, SMT ntau yam. Raws li cov kev hloov kho tso tawm disc ceramic capacitors tau nkag mus tau zoo, thiab raws li SMT cov khoom siv, cov capacitors tej hub muaj nyob hauv txhua hom ntawv tawm tswv yim. Xws li cov capacitors tej hub siv nyob rau hauv yuav luag txhua hom khoom siv hluav taws xob.

Cov kev ua tau tiag tiag los ntawm ceramic capacitors yog tiag tiag raws li qhov siv dielectric. Siv cov khoom siv niaj hnub dielectrics, cov txiaj ntsig loj heev tau txais, tab sis nws tiag tiag kuj yuav tsum tau soj ntsuam cov ntsuas nrog rau qhov ntsuas qhov kub thiab lub siab ntev. Cov theem sib txawv ntawm cov hauj lwm zoo feem ntau tswj hwm nrog kev siv dielectric siv, thiab yog li nws yuav tsum txiav txim siab hom dielectric los ntawm cov ceramic capacitor.

Ceramic capacitors sib txawv hauv qhov tseem ceeb ntawm cov nuj nqis tsawg dua li ntawm ob peb picofarads ze rau 0.one microfarads. Hauv kev pom los ntawm cov kev xaiv dav thiab kev haum rau RF cov kev pab cuam no tau ua haujlwm rau kev sib txuas thiab decoupling apps tshwj xeeb. Ntawm no tsuav yog los ntawm ntau qhov feem ntau siv hom nyob pheej yig thiab trustworthy ntxiv rau cov yam tsis tau yog tshwj xeeb tshaj yog thaum no yog nyob ntawm lub caij nyoog dielectric siv.

Tsim muaj qhov yooj yim tej hub

Ceramic capacitors yuav yog qhov ua haujlwm ntawm cov npliag hluav taws xob hauv ntiaj teb tam sim no. Ceramic capacitors tau siv ntau lab raws li qhov sib txuas los ntawm lawv cov nqi thiab ua haujlwm tau zoo. Muaj ntau cov dav dielectrics uas feem ntau ua haujlwm raws li tau piav qhia hauv qab, tab sis vim tias qhov txheeb xyuas nrog cov ceramic capacitor qhia, lawv yuav tag nrho cov ceramic hauv qhov.

Txhawm rau kom paub tseeb tias muaj ntau yam ntawm capacitance feem ntau tau txais hauv ib tus kheej lub pob hluav taws xob, cov kab hluav taws xob (capacitors), xws li hom capacitor muaj ntau cov khaubncaws sab nraud povtseg. Qhov no nce qib ntawm capacitance los tso cai rau qhov tsim nyog ntawm qhov muaj peev xwm feem ntau ua tiav.

Ceramic capacitors tau tam sim no nyob hauv peb hom tseem ceeb tshaj plaws txawm tias lwm yam tau txais:

leaded disc ceramic capacitors rau raws li qhov tshwm sim ntawm qhov mounting uas yog cob coated

multilayer pem teb mount nti tej hub capacitors

Tus kws tshwj xeeb microwave tsis muaj hmoov txhuas tsis muaj xim disc ceramic capacitors uas tshwm sim los npaj rau hauv qhov tsis pub dhau ntawm PCB thiab raug muag hauv qhov chaw

Dua li ntawm qhov tseeb tias nws yog qhov tsim nyog kom tau txais lwm yam hom ntawm cov capacitor ceramic, cov no yog cov hom loj uas yuav nyob niaj hnub no. Ntawm cov saum npoo mount ntau yam siv nyob rau hauv qhov khoom loj tshaj los ntawm qhov tseem ceeb vim yog qhov tseeb nrog kev tsim khoom siv tawm tam sim no rau cov cuab yeej digital.

Tej hub dielectrics

Tej hub capacitors muaj kev xaiv ntau ntawm cov sib txawv ntawm cov ceramic dielectrics vim tias lub hauv paus nrog tus capacitor. Tej hub dielectrics yog tsim los ntawm ntau cov ntaub ntawv ntawm ceramic dielectric. Tus qauv npliag ntawm cov khoom siv hluav taws xob sib txawv uas siv hauv cov twj siv hluav taws xob ua kom zoo nkauj txawv ntawm cov chaw tsim khoom ib qho mus rau lwm qhov tab sis cov sib txuas sib txuas muaj xws li titanium dioxide, strontium titanate, thiab barium titanate.

Hauv kev pom ntawm qhov txawv txav ntawm cov ceramics siv hauv cov ntsuas hluav taws xob EIA (Digital Industries Alliance) cais cov ceramics rau cov pawg. Nyob rau hauv dav dav cov pab pawg tsawg dua lossis tsev kawm ntawv muaj ntau dua qhov zoo ntawm txhua qhov, tab sis qhov ntawd feem ntau nyob ntawm kev siv nyiaj ntawm qhov ntev. Daim ntawv nyob rau hauv tsuas yog hais txog txhua qeb txhais cov txheej txheem khiav hauj lwm kub, kub drift, kam rau ua, thiab lwm yam.

Qeb 1: Lub Tsev Kawm Ntawv 1 ceramic capacitors yog qhov tseem ceeb tshaj plaws ruaj khov ntawm cov ceramic capacitor nrog qhov ntsuas kub. Lawv twb muaj cov yam ntxwv zoo thiab lawv cov khoom yog cov ywj pheej ntawm zaus hauv cov kab tawm txawv.

Cov sib txuas sib xyaw siv li cov dielectrics yog magnesium titanate rau qhov ntsuas kub tsis kam rau siab, lossis calcium titanate rau cov capacitors uas muaj qhov ntsuas tsis zoo. Ua siv ntawm kev sib txuas ntawm cov ntawd thiab tseem muaj lwm lub tebchaw nws tuaj yeem nqa tau kom tau txais dielectric tsis tu ncua ntawm tsib thiab 150. Kuj qhov ntsuas kub coefficients ntawm nruab nrab ntawm + 40 thiab -5000 ppm / C tuaj yeem tau txais.

Cov chav kawm ib lub zog tseem tseem muab koj qhov kev ua tau zoo tshaj plaws nrog kev hais txog kev tsis nco qab. Qhov no feem ntau tseem ceeb heev hauv ntau lub hom phiaj. Ib qho kev txiav txim siab yuav yog 0.15%. Nws tseem muaj peev xwm kom tau txais qhov tseeb ntawm qhov tseeb siab (~ ib%) lub tsev kawm ntawv 1 capacitors uas tsis xws li cov qauv zoo dua li 5% lossis 10% kam rau ua. Cov kev qhia siab tshaj qhov tseeb tshaj plaws 1 capacitors raug xaiv C0G lossis NP0.

Hom 2: Lub tsev kawm ntawv ob peb lub capacitors muab cov kev ua tau zoo dua ntxiv nrog rau qhov muaj feem cuam rau volumetric, tab sis nws yog nyob ntawm tus nqi ntawm qhov tsawg dua qhov raug thiab qhov sib npaug. Ua qhov kawg ntog cov no ib txwm ua haujlwm rau qhov suav daws, txuas thiab dhau ntawm daim ntawv thov uas qhov tseeb tsis yog ntawm qhov tseem ceeb. Ib chav kawm tshwj xeeb ob lub capacitor tuaj yeem hloov kho kom haum tau 15% lossis tshaj li ntawm -50C rau + 85 C kub thiab nws tuaj yeem ua haujlwm rau dissipation element ntawm ob peb of.5%. Nws tuaj yeem muaj qhov tshwm sim rau cov neeg tsis muaj zog (txij li kaum% nqes mus rau + 20 / -80%). Howeer rau ntau zog heev cov nuj nqis no yuav tsis muaj qhov teeb meem.

Qeb ob peb: Hom peb lossis ntau dua ceramic capacitors muab koj qhov tseem ntau volumetric efficiency, tab sis tsis tau ib zaug ntxiv qhov no tuaj yeem nrog cov kev siv ntawm qhov tsis muaj zog thiab qhov sib npaug thiab tseem muaj qhov tsawg tsawg dissipation. Cov no kuj tseem tsis tuaj yeem tiv taus qhov hluav taws xob siab dua. Lub dielectric siv feem ntau yog barium titanate uas muaj dielectric txuas ntxiv ntawm kwv yees li ntawm 1250.

Ib hom lus tsis tseem ceeb ntawm qee lub capacitor yuav hloov kho nws lub peev xwm ntawm -22% rau + 50% ntau dua li qhov ntsuas kub ntau ntawm + 10C rau + 55C. Tej zaum nws kuj tseem yuav muaj qhov teeb meem tawm heev uas ze ntawm peb lossis ntau dua rau 5%. Nws yuav muaj qhov ntsuas pom tsis zoo heev (feem ntau, 20%, lossis -20 / + 80%). Raws li qhov tshwm sim, chav kawm ntau lub tais hluav taws xob (capacitors) feem ntau siv los ua decoupling lossis hauv lwm lub zog muab cov laj thawj qhov chaw qhov tseeb yuav tsis muaj qhov xwm txheej. Tau hais tias lawv yuav tsum tsis txhob siv nyob rau hauv lub hom phiaj qhov twg cov ntsia hlau loj muaj nyob raws li cov no yuav ua mob rau lub capacitor yog tias lawv tshaj qhov ntsuas hluav taws xob.

Lub ib hlis ntuj 19, 2017