Switching Power Supply RCD Spike Absorption Circuit Principle Analysis
Rau qhov hloov hluav taws xob siv hluav taws xob siv lub ramp nthwv dej kom them nyiaj rau lub luag haujlwm ntawm lub transistor, kab lus no hais txog lub luag haujlwm ntawm R4, D1, C6 thiab lub hauv paus ntsiab lus. Coj koj los txheeb xyuas lub luag haujlwm ntawm txhua qhov ntawm cov khoom siv hluav taws xob hloov pauv.
4 resistor, D1 diode, C6 capacitor yog ib qho hluav taws xob nqus hluav taws xob, vim nws yog ib qho hluav taws xob-capacitor-diode circuit, hu ua RCD absorption circuit. Yog li vim li cas thiaj ntxiv ib qho hluav taws xob nqus hluav taws xob? Nws yog vim hais tias nws yog ib qho tsim nyog los tiv thaiv MOS raj dhau-voltage tawg, thiab txwv qhov siab tshaj qhov hluav taws xob rau MOS raj tiv taus qhov hluav taws xob. Yog li ntawd MOS raj tuaj yeem ua haujlwm nyab xeeb, yog li nws ua haujlwm li cas.
Raws li qhov tshwm sim ntawm transformer ntau lawm yuav muaj qee yam to hauv inductance, qhov to inductance yog dab tsi, yog qhov sib piv ntawm transformer thiab winding coils generated nyob rau hauv lub transformer ua hauj lwm thawj lub zog tsis tuaj yeem hloov mus rau theem nrab, ces vim inductance yuav. tsim lub zog rov qab electromotive, uas ua rau muaj qhov rov qab voltage thiab lub superposition ntawm cov khoom siv hluav taws xob tsim hluav taws xob hluav taws xob, qhov hluav taws xob no yuav ntau dua li tus nqi ntawm qhov kev tiv thaiv hluav taws xob ntawm MOS, kev tawg ntawm MOS raj.
Yog li koj yuav tsum tau koom nrog qhov sib nqus nqus Circuit Court, nyob rau hauv lub transformer thawj kauj, thiaj li yuav nqus tau cov coil generated los ntawm lub rov qab electromotive quab yuam, koom lub RCD absorption circuit, RCD ua hauj lwm txheej txheem, thaum lub MOS raj conduction, voltage ntws los ntawm lub transformer thawj kauj, them lub kauj, thaum lub MOS raj kaw, lub inductor generates ib tug rov qab electromotive quab yuam, lub transformer theem nrab voltage tso tawm los ntawm lub diode, vim los ntawm cov thawj kauj, tsis tuaj yeem hloov mus rau theem nrab, qhov ntau dhau. . Tsis tuaj yeem hloov mus rau qhov thib ob, lub zog ntau dhau yuav raug suav nrog cov khoom siv hluav taws xob, ua rau muaj qhov sib txawv ntawm qhov hluav taws xob, qhov hluav taws xob loj los ntawm diode D1 ntawm lub capacitor C6 them, hauv MOS conductive dua, lub capacitor C6 ntawm lub voltage los ntawm tus resistor R4 tawm, lub zog dhau los ntawm tus resistor kom haus, RCD ntawm lub voj voog ua haujlwm tiav, txuas ntxiv mus rau lub voj voog tom ntej.
Ntawm no cov diode xaiv ntawm ceev rov qab diode, kuj thiab capacitance raws li lub Circuit Court debugging los txiav txim qhov tsis, qhov luaj li cas ntawm resistor tus nqi, qhov ntau dua qhov nqus ntawm lub zog, uas yuav cuam tshuam rau kev ua tau zoo, lawv lub hom phiaj yog siv lub Circuit Court rau. tsim lub zog ntau dhau, tsis tuaj yeem haus lub zog hluav taws xob hauv Circuit Court, uas cuam tshuam rau thawj electromotive quab yuam, kev hloov ntawm electromotive quab yuam mus rau theem nrab yog tsawg, txo cov kev hloov dua siab tshiab. Resistor tus nqi yog loj heev, nyob rau hauv qhov tso tawm, tus nqi paug yog qeeb, lub spike voltage yuav poob maj mam, lub spike voltage yuav siab tshaj lub MOS raj withstand voltage, ua rau MOS raj tawg. Yog li tus nqi ntawm cov resistor raug xaiv nyob rau hauv Circuit Court debugging, debugging nrog ib tug oscilloscope kom pom lub waveform ntawm lub MOS raj D-ncej, koj muaj peev xwm kom meej meej pom lub spike voltage, hloov lub resistor yuav hloov lub spike voltage, capacitance kuj hloov. qhov loj ntawm qhov sib npaug ntawm qhov hluav taws xob, thiab cov resistors nrog kev siv lub hom phiaj kawg, yog kom nqus tau qhov hluav taws xob loj, lub zog ntau dhau, tsis tuaj yeem haus lub zog hluav taws xob.
Kev nqus hluav taws xob muaj peb yam, ib qho yog RCD, TVS ntu ntu kev tiv thaiv diode nrawm rov qab diode muaj pes tsawg leeg, muaj cov hluav taws xob tswj hluav taws xob diodes thiab ceev rov qab diode Tube, txhua tus muaj nws qhov zoo thiab qhov tsis zoo, RCD Circuit Court siv ntau dua, ob yav tas los kuj pom ntau zaus. Switching fais fab mov
