Lub hauv paus ntsiab lus ntawm impedance txuam
1. ntshiab kuj Circuit Court
Hauv cov tsev kawm ntawv theem nrab physics, hluav taws xob tau hais txog qhov teeb meem no: qhov tsis kam ntawm R cov khoom siv hluav taws xob, txuas nrog lub peev xwm hluav taws xob ntawm E, kev tiv thaiv sab hauv ntawm r roj teeb pob, nyob rau hauv cov xwm txheej dab tsi ntawm cov khoom siv hluav taws xob yog qhov loj tshaj plaws?Thaum cov kev tawm tsam sab nraud yog sib npaug rau cov kev tawm tsam sab hauv, lub zog tawm ntawm lub zog hluav taws xob mus rau sab nraud Circuit Court yog qhov loj tshaj plaws, uas yog ib qho kev sib txig sib luag ntawm lub zog hluav taws xob.Yog tias hloov los ntawm AC Circuit Court, tib yam yuav tsum ua raws li cov xwm txheej ntawm R = r Circuit Court kom phim.
2. reactance Circuit Court
Lub impedance Circuit Court yog qhov nyuaj dua li cov ntshiab tiv thaiv Circuit Court, ntxiv rau qhov kev tiv thaiv hauv Circuit Court muaj cov capacitors thiab inductors.Cheebtsam, thiab ua haujlwm nyob rau hauv tsawg zaus los yog high-frequency AC circuits.Nyob rau hauv AC circuits, tsis kam, capacitance thiab inductance ntawm alternating tam sim no cuam tshuam yog hu ua impedance, qhia los ntawm tsab ntawv Z. Ntawm no, cov cuam tshuam cuam tshuam ntawm capacitance thiab inductance ntawm alternating tam sim no hu ua capacitive reactance thiab inductive reactance thiab feem.Tus nqi ntawm capacitive reactance thiab inductive reactance muaj feem xyuam rau qhov zaus ntawm kev hloov tam sim no ua haujlwm ntxiv rau qhov loj ntawm lub capacitance thiab inductance nws tus kheej.Nws yog ib nqi sau cia hais tias, nyob rau hauv ib tug reactance Circuit Court, tus nqi ntawm kuj R, inductive reactance thiab capacitive reactance ob yuav tsis tau ntxiv los ntawm yooj yim arithmetic, tab sis feem ntau siv impedance triangulation txoj kev xam.Yog li, lub impedance Circuit Court kom ua tiav qhov sib txuam dua li cov hluav taws xob hluav taws xob ua kom muaj zog ntau dua, ntxiv rau cov khoom siv hluav taws xob thiab cov khoom siv hluav taws xob hauv cov khoom siv tiv thaiv kev tiv thaiv yog sib npaug, tab sis kuj yuav tsum muaj qhov sib npaug ntawm qhov sib npaug thiab kos npe ntawm qhov sib txawv (conjugate txuam. );los yog resistive tivthaiv thiab reactance Cheebtsam yog sib npaug (non-reflective matching).Ntawm no yog hais txog cov reactance X, uas yog, inductive XL thiab capacitive reactance XC qhov txawv (tsuas yog rau series circuits, yog hais tias lub parallel circuits yog nyuaj rau xam).Yuav kom ua tau raws li cov xwm txheej saum toj no yog hu ua impedance txuam, lub load uas tuaj yeem tau txais lub zog siab tshaj plaws.
Tus yuam sij rau impedance txuam yog qhov tso zis impedance ntawm pem hauv ntej theem yog sib npaug rau input impedance ntawm theem tom qab.Lub input impedance thiab tso zis impedance yog dav siv nyob rau hauv hluav taws xob circuits ntawm txhua theem, txhua yam ntawm cov ntsuas ntsuas thiab txhua yam ntawm cov khoom siv hluav taws xob.Yog li dab tsi yog input impedance thiab output impedance?Lub input impedance yog impedance ntawm Circuit Court rau lub teeb liab qhov chaw.Raws li pom nyob rau hauv daim duab 3 amplifier, nws cov input impedance yog tshem tawm cov teeb liab qhov chaw E thiab internal kuj r, los ntawm AB xaus rau hauv qhov sib npaug impedance.Nws tus nqi yog Z = UI / I1, uas yog, qhov piv ntawm cov input voltage thiab input tam sim no.Rau lub teeb liab qhov chaw, lub amplifier ua nws cov load.Piv txwv li, qhov sib npaug load tus nqi ntawm lub amplifier yog tus nqi ntawm cov input impedance.Qhov loj ntawm cov input impedance tsis zoo ib yam rau cov sib txawv circuits.
Piv txwv li, qhov siab dua qhov input impedance (hu ua voltage rhiab heev) ntawm qhov voltage block ntawm ib tug multimeter, qhov me me shunt ntawm lub Circuit Court nyob rau hauv kev ntsuam xyuas thiab qhov me me qhov ntsuas qhov yuam kev.Qhov qis ntawm cov input impedance ntawm tam sim no thaiv, qhov me dua qhov kev faib hluav taws xob rau hauv Circuit Court nyob rau hauv kev sim, thiab yog li qhov me me qhov ntsuas qhov yuam kev.Rau lub hwj chim amplifiers, thaum cov zis impedance ntawm lub teeb liab qhov sib npaug ntawm input impedance ntawm lub amplifier Circuit Court, nws yog hu ua impedance txuam, thiab ces lub amplifier Circuit Court yuav tau txais lub siab tshaj plaws hwj chim ntawm cov zis.Output impedance yog impedance ntawm Circuit Court tiv thaiv load.Raws li nyob rau hauv daim duab 4, lub hwj chim mov ntawm lub input sab ntawm lub Circuit Court yog luv luv, lub tso zis sab ntawm lub load raug tshem tawm, qhov sib npaug impedance los ntawm cov zis sab ntawm lub CD yog hu ua cov zis impedance.Yog hais tias lub load impedance tsis sib npaug ntawm cov zis impedance, hu ua impedance mismatch, lub load tsis tuaj yeem tau txais lub zog siab tshaj plaws.Qhov piv ntawm cov zis voltage U2 thiab cov zis tam sim no I2 yog hu ua cov zis impedance.Qhov loj ntawm qhov tso zis impedance nyob ntawm qhov sib txawv circuits muaj qhov sib txawv.
Piv txwv li, ib qho hluav taws xob qhov hluav taws xob yuav tsum muaj qhov tso zis tsawg impedance, thaum lub hauv paus tam sim no yuav tsum muaj qhov tso zis siab impedance.Rau lub amplifier Circuit Court, tus nqi ntawm cov zis impedance qhia tias nws muaj peev xwm nqa tau ib lub load.Feem ntau, qhov me me tso tawm impedance ua rau muaj peev xwm nqa tau siab.Yog hais tias qhov tso zis impedance tsis tuaj yeem sib phim rau qhov load, transformer lossis network circuit tuaj yeem raug ntxiv kom ua tiav qhov sib tw.Piv txwv li, lub transistor amplifier feem ntau yog txuas nrog cov zis transformer nruab nrab ntawm lub amplifier thiab tus neeg hais lus, thiab cov zis impedance ntawm lub amplifier yog txuam nrog cov thawj impedance ntawm transformer, thiab cov impedance theem nrab ntawm lub transformer yog matched nrog impedance ntawm. tus hais lus.Qhov thib ob impedance ntawm lub transformer yog txuam nrog impedance ntawm lub suab nrov.Lub transformer hloov qhov impedance piv los ntawm qhov sib piv ntawm cov thawj thiab theem nrab windings.Nyob rau hauv qhov tseeb hluav taws xob circuits, feem ntau ntsib nrog lub teeb liab qhov chaw thiab amplifier Circuit Court los yog amplifier Circuit Court thiab load impedance tsis sib npaug zos rau qhov teeb meem, yog li lawv tsis tuaj yeem txuas ncaj qha.Qhov kev daws teeb meem yog ntxiv ib qho kev sib txuam lossis kev sib txuas ntawm lawv.Thaum kawg, nws yuav tsum tau muab sau tseg tias impedance txuam tsuas yog siv tau rau cov hluav taws xob circuits.Vim hais tias lub zog ntawm cov teeb liab kis tau nyob rau hauv hluav taws xob circuits yog inherently tsis muaj zog, kev sib txuam yuav tsum tau ua kom lub zog tso zis ntau zog.Hauv cov khoom siv hluav taws xob, kev sib txuam feem ntau tsis suav nrog, vim tias nws tuaj yeem ua rau cov khoom siv hluav taws xob ntau dhau thiab kev puas tsuaj rau cov khoom siv.
Daim ntawv thov ntawm Impedance Matching
Rau cov teeb liab dav dav dav dav, xws li moos teeb liab, tsheb npav teeb liab, thiab txawm tias mus txog ntau pua megabytes ntawm DDR cov cim, thiab lwm yam, cov khoom siv dav dav transceiver inductive thiab capacitive impedance yog qhov me me, cov txheeb ze tsis kam (xws li, qhov tseeb ntawm lub impedance) uas tuaj yeem tsis quav ntsej, thiab ntawm qhov no, impedance txuam tsuas yog yuav tsum tau coj mus rau hauv tus account qhov tseeb ntawm qhov tuaj yeem ua tau.
Nyob rau hauv lub tshav pob ntawm lub xov tooj cua zaus, ntau yam khoom siv xws li kav hlau txais xov, amplifiers, thiab lwm yam., nws cov input thiab output impedance tsis yog tiag tiag (tsis ntshiab kuj), thiab nws xav txog ib feem (capacitive los yog inductive) yog loj heev uas nws yuav tsis raug ignored. , ces peb yuav tsum siv txoj kev sib piv.
Post lub sij hawm: Aug-17-2023