Ib qho kev piav qhia txog 3 hom sib txawv ntawm cov khoom siv hluav taws xob
Thaum twg yuav tsum muaj kev ruaj ntseg, txhim khu kev ruaj ntseg, cov khoom siv hluav taws xob yog cov mus-mus tivthaiv. Lawv siv cov khoom siv hluav taws xob tawm thiab tsim kom muaj qhov tso tawm qhov hluav taws xob tsis hais txog ntawm qhov input voltage nyob ntawm ib qhov kev ntsuas hluav taws xob los yog theem ntsuas qhov nruab siab (los ntawm xaiv sab nraud Cheebtsam).
Cov kev cai no tsis tuaj yeem ua raws li cov kev tawm tswv yim ntawm cov zis hluav taws xob los ntawm ntau hom kev tawm tswv yim, qee qhov yooj yim xws li Zener diode thaum lwm tus muaj xws li cov tswv yim nyuaj uas tuaj yeem txhim kho kev kawm, kev cia siab, kev ua haujlwm, thiab ntxiv lwm cov nta xws li boosting cov zis hluav taws xob saum cov input voltage qhov kev tiv thaiv hluav taws xob.
Hom Voltage Regulators
Muaj ntau hom kev tswj hluav taws xob uas muaj ntawm cov nqi pheej yig heev. Qhov feem ntau pheej yig thiab feem ntau qhov yooj yim hom voltage regulator siv yog linear voltage regulators.
Tawm regulators tuaj nyob rau hauv ob peb hom, yog cov compact, thiab siv feem ntau nyob rau hauv tsawg voltage, tsawg zog systems.
Switching regulators muaj ntau yam dua li linear voltage regulators, tab sis lawv nyuab zog ua hauj lwm nrog thiab kim kim.
Tawm Txuj Ci
Ib qho ntawm txoj kev yooj yim tshaj plaws los tswj cov khoom siv hluav taws xob thiab muab qhov hluav taws xob ruaj khov rau cov khoom siv hluav taws xob yog siv tus qauv 3-pin linear voltage regulator xws li LM7805, uas yog siv 5 volt 1 amp tso tawm nrog ib qho input voltage ntawm mus txog 36 volts ( nyob ntawm tus qauv).
Tawm regulators ua hauj lwm los ntawm kev kho cov kev ua hauj lwm zoo ntawm cov tswj raws li kev tawm tswv yim voltage, yeej tseem zoo los ua qhov hluav taws xob divider hluav taws xob. Qhov no cia tus tswj cov khoom tso tawm ib qho kev siv qhov hluav taws xob tsis zoo kiag li cas los xij uas tam sim no load yog muab rau nws, mus txog rau nws lub peev xwm tam sim no.
Ib qho ntawm cov kev lag luam loj rau cov qauv hluav taws xob tawm yog qhov tsawg kawg nkaus ntawm qhov muaj teeb meem ntawm qhov voltage regulator, uas yog 2.0 volts ntawm tus qauv LM7805 linear voltage regulator. Qhov no txhais tau tias kom tau qhov ruaj khov 5 volts tso tawm, tsawg kawg yuav tsum tau muaj 7 volt input. Qhov kev poob siab no muaj lub luag haujlwm loj nyob hauv lub hwjchim uas tawm ntawm cov kab khiav tawm, uas yuav tsum tau dissipate tsawg kawg yog 2 watts yog tias nws xa ib 1 amp load (2 volt voltage nco lub sij hawm 1 amp).
Lub zog faib tau qhov loj tshaj qhov txawv nruab nrab ntawm qhov tawm tswv yim thiab cov zis hluav taws xob. Yog li, piv txwv li, thaum lub sijhawm 7 volts ntawm 5 volts delivering 1 amp yuav dissipate 2 watts mus txog cov kab tawm, ib 10 volt qhov tswj raws li 5 volts delivering tib yam tam sim no yuav dissipate 5 watts, ua tus regulator xwb 50% npaum .
Switching Regulators
Tawm regulators yog cov tswv yim zoo rau cov uas tsis muaj hwj chim, cov nqi qis dua qhov uas qhov sib txawv ntawm qhov sib txawv ntawm qhov tawm tswv yim thiab cov zis yog tsawg thiab tsis muaj hwj chim ntau. Qhov loj tshaj ntawm sab rau cov tswj cai tawm yog tias lawv muaj kev sib txig sib luag, uas yog qhov uas hloov cov neeg saib xyuas tuaj rau hauv kev ua si.
Thaum yuav tsum tau muaj kev ua haujlwm siab lossis muaj ntau yam kev tawm tswv yim, yuav tsum tau muaj kev cuam tshuam nrog cov khoom siv hluav taws xob, qhov kev hloov qhov zoo tshaj plaws. Switching voltage regulators muaj hwj huam ua tau zoo ntawm 85% los sis zoo dua piv rau cov kab hluav taws xob tswj qhov kev khiav hauj lwm uas feem ntau 50%.
Hloov regulators feem ntau yuav tsum tau ntxiv cov khoom tshaj li cov cai tswj tawm, thiab qhov tseem ceeb ntawm cov khoom muaj feem ntau ntawm kev cuam tshuam rau tag nrho cov kev kawm ntawm kev hloov regulators dua li cov cai regulators.
Kuj muaj ntau qhov kev tsim teebmeem ntawm kev siv cov tswj regulators zoo yam tsis muaj kev cuam tshuam cov kev ua tau los yog tus cwj pwm ntawm tag nrho ntawm Circuit los ntawm lub suab nrov nrov uas tus tswj tau ua tau.
Zener Diodes
Ib qho kev simplest txoj kev tswj qhov ntsuas yog nrog Zener diode. Thaum ib tus neeg tswj linear yog ib qho kev tivthaiv zoo nkauj nrog ob peb yam ntxiv uas yuavtsum tau ua haujlwm thiab tsis tsim ntau yam nyuaj, lub Zener diode tuaj yeem tsim cov kev tswj hluav taws xob txaus rau qee zaum nrog ib qho kev tivthaiv xwb.
Txij li ib Zener diode shunts tag nrho ntxiv voltage saum nws lub neej tsis zoo voltage chaw mus rau hauv av, nws yuav siv raws li ib tug heev yooj yim voltage regulator nrog lub tso zis voltage rub dhau lub ua ntawm zener diode.
Hmoov tsis, Zeners feem ntau heev nyob rau hauv lawv lub peev xwm tswj fais fab uas txwv qhov uas lawv tuaj yeem raug siv raws li cov kev tswj hwm hluav taws xob kom tsis tshua muaj zog siv daim ntawv sau npe xwb. Thaum siv Zener diodes li no, nws zoo tshaj plaws kom txo tau lub hwj huam uas muaj peev xwm khiav los ntawm Zener los ntawm kev xaiv cov kev xaiv kom zoo dua.