Cov lus piav qhia ntxaws txog txoj hauv kev ua haujlwm ntawm linear tswj fais fab mov
Raws li kev ua haujlwm hauv lub xeev ntawm cov kav dej tswj, peb feem ntau faib cov kev tswj fais fab rau hauv ob pawg: linear tswj fais fab mov thiab hloov hluav taws xob tswj hluav taws xob. Tsis tas li ntawd, muaj cov khoom siv hluav taws xob me me uas siv lub zog tswj hluav taws xob.
Cov kab hluav taws xob tswj hluav taws xob tau hais los ntawm no yog hais txog DC tswj fais fab mov uas ua haujlwm nyob rau hauv lub xeev linear nrog lub raj hloov. Lub raj hloov ua haujlwm nyob rau hauv lub xeev linear, uas tuaj yeem nkag siab tau raws li hauv qab no: RW (saib kev tsom xam hauv qab no) yog qhov sib txawv tsis tu ncua, uas yog, linear. Hauv kev hloov cov khoom siv hluav taws xob, qhov hloov pauv hloov pauv (feem ntau hu ua kev hloov pauv hloov pauv hauv cov khoom siv hluav taws xob hloov hluav taws xob) ua haujlwm nyob rau hauv ob lub xeev: on - nrog qis heev; Tawm - Qhov tsis kam yog siab. Lub raj ua haujlwm nyob rau hauv lub xeev on/off yog kom meej meej tsis nyob rau hauv ib tug linear lub xeev.
Linear tswj fais fab mov yog ib yam tseem ceeb ntawm DC tswj fais fab mov. Cov yam ntxwv ntawm linear regulated DC fais fab mov yog: cov zis voltage yog qis dua qhov input voltage; Cov lus teb ceev ceev thiab cov zis me me ripple; Tsawg suab nrov tsim los ntawm kev ua haujlwm; Tsawg efficiency (LDO, uas feem ntau pom niaj hnub no, zoo nkaus li daws teeb meem efficiency); Kev tsim hluav taws xob siab (tshwj xeeb tshaj yog cov khoom siv hluav taws xob siab) ua rau lub suab nrov nrov rau lub cev.
Lub hauv paus ntsiab lus ua haujlwm: Cia peb xub siv daim duab hauv qab no los qhia txog lub hauv paus ntsiab lus ntawm kev tswj hluav taws xob hauv cov kab hluav taws xob tswj hluav taws xob.
Qhov sib txawv ntawm cov resistor RW thiab load resistor RL tsim ib qho hluav taws xob faib hluav taws xob, nrog rau qhov tso zis hluav taws xob ntawm:
Uo=Ui × RL/(RW plus RL), yog li ntawd, los ntawm kev kho qhov loj ntawm RW, cov zis voltage yuav hloov tau. Thov nco ntsoov tias hauv qhov sib npaug no, yog tias peb tsuas saib tus nqi hloov pauv ntawm qhov hloov pauv hloov RW, cov zis ntawm Uo tsis yog linear, tab sis yog peb saib RW thiab RL ua ke, nws yog linear. Tsis tas li ntawd nco ntsoov tias peb daim duab tsis piav qhia txog RW cov hlau lead kawg uas txuas rau sab laug, tab sis sab xis. Txawm hais tias yuav tsis muaj qhov sib txawv ntau hauv cov qauv, kev kos duab ntawm txoj cai yog qhia txog cov ntsiab lus ntawm "sampling" thiab "feedback" - qhov tseeb, feem ntau ntawm cov khoom siv hluav taws xob ua haujlwm hauv cov qauv thiab cov lus tawm tswv yim, thiab cov tswv yim feedforward tsis tshua siv. , los yog yooj yim pab txoj kev.
Cia peb mus txuas ntxiv: yog tias peb hloov qhov hloov pauv hloov pauv hauv daim duab nrog lub transistor lossis qhov cuam tshuam ntawm cov transistor, thiab tswj tus nqi ntawm qhov "tsis paub meej resistor" los ntawm kev txheeb xyuas cov zis voltage, kom cov zis voltage nyob tas li, peb ua tiav lub hom phiaj. ntawm voltage stabilization. Qhov no transistor lossis field-effect transistor yog siv los kho qhov voltage tso zis loj, yog li nws yog hu ua kev hloov kho transistor.
Vim lub fact tias cov hloov raj yog txuas nrog nyob rau hauv series ntawm lub hwj chim mov thiab lub load, nws yog hu ua ib tug series tswj fais fab mov. Raws li txoj cai, muaj ib qho kev tswj hwm hluav taws xob sib txuas, uas kho cov zis hluav taws xob los ntawm kev sib txuas ntawm cov kav dej tswj nrog lub nra. Ib tug raug siv voltage regulator TL431 yog ib yam ntawm parallel tswj fais fab mov. Lub ntsiab lus ntawm kev sib txuas yog los xyuas kom meej qhov "stability" ntawm lub emitter voltage ntawm lub attenuation amplifier raj los ntawm shunt, raws li qhia nyob rau hauv daim duab 2. Tej zaum daim duab no tsis tam sim ntawd qhia tias nws yog "parallel", tab sis raws li kev soj ntsuam ze, nws yog qhov tseeb. Txawm li cas los xij, nws yuav tsum tau muab sau tseg tias qhov voltage regulator siv ntawm no ua haujlwm nyob rau hauv nws cheeb tsam nonlinear. Yog li ntawd, yog tias nws suav hais tias yog lub zog hluav taws xob, nws kuj yog lub zog tsis muaj zog. Txhawm rau kom yooj yim ntawm txhua tus neeg nkag siab, cia peb saib rau daim duab tsim nyog tom qab kom txog thaum peb tuaj yeem nkag siab qhov tseeb.
Vim lub fact tias cov hloov raj ua raws li ib tug resistor thiab generates tshav kub thaum tam sim no ntws los ntawm lub resistor, lub adjustable tube kev khiav hauj lwm nyob rau hauv ib tug linear xeev feem ntau generates ib tug loj npaum li cas ntawm tshav kub, uas ua rau tsis tshua muaj efficiency. Qhov no yog ib qho ntawm cov teeb meem tseem ceeb ntawm cov khoom siv hluav taws xob linear tswj. Yog xav paub ntxiv txog kev nkag siab ntau ntxiv ntawm cov khoom siv hluav taws xob linear, thov mus saib hauv phau ntawv analog electronic circuit. Peb lub hom phiaj tseem ceeb ntawm no yog los pab txhua tus kom paub meej cov ntsiab lus no thiab lawv txoj kev sib raug zoo.
