Yuav ua li cas hloov PWM rau analog?
Yuav ua li cas hloov PWM rau analog?

Video: Yuav ua li cas hloov PWM rau analog?

Video: Yuav ua li cas hloov PWM rau analog?
Video: yuav ua li cas lub neej thiaj hloov pauv kom zoo dua qub 2024, Kaum ib hlis
Anonim

Hmoov zoo, nws yooj yim rau hloov a PWM output rau ib analog voltage theem, tsim ib qhov tseeb DAC. Txhua yam uas xav tau yog ib qho yooj yim low-pass lim ua los ntawm cov resistor thiab ceramic capacitor. Qhov yooj yim RC low-pass lim tau pom hauv daim duab thib peb hloov tus PWM signal rau a hluav taws xob proportional rau lub luag hauj lwm voj voog.

Kuj yuav paub yog, koj yuav ua li cas hloov analog rau digital?

ADCs ua raws li ib ntus thaum converting analog qhia rau digital . Lawv thawj zaug ua piv txwv lub teeb liab, ces quantify nws los txiav txim qhov kev daws teeb meem ntawm lub teeb liab, thiab thaum kawg teem binary qhov tseem ceeb thiab xa mus rau lub system nyeem cov digital teeb liab. Ob yam tseem ceeb ntawm ADC yog nws qhov piv txwv tus nqi thiab kev daws teeb meem.

Ib sab saum toj no, koj yuav suav PWM voltage li cas? Txhawm rau txiav txim siab proportional PWM tso zis hluav taws xob , siv qhov no qauv : (Duty ÷ 256) x 5 V. Piv txwv li, yog Duty yog 100, (100 ÷ 256) x 5 V = 1.953 V; PWM outputs ib lub tsheb ciav hlau ntawm pulses uas nws nruab nrab hluav taws xob yog 1.953 V. Nyob rau hauv thiaj li yuav hloov PWM nyob rau hauv ib qho analog hluav taws xob peb yuav tsum lim tawm cov pulses thiab khaws qhov nruab nrab hluav taws xob.

Ntawm no, koj yuav lim PWM teeb liab li cas?

Rau qhov yooj yim lim siv ib tug resistor thiab capacitor nyob rau hauv series thoob plaws lub PWM tso zis rau hauv av. Lub capacitor yog grounded thiab cov R thiab C node voltage muaj cov zis lim. Ib tug sophisticated lim tej zaum yuav ua raws li qhov kev txiav txim thib 2 ntawm op-amp lim Thiab qhov no yog zoo li hloov lub resistor nrog ib tug inductor.

Vim li cas PWM siv?

A Pulse Width Modulation ( PWM ) Teeb liab yog ib txoj hauv kev los tsim cov teeb liab analog siv qhov chaw digital. PWM teeb liab yog siv rau ntau yam kev tswj kev siv. Lawv qhov kev siv tseem ceeb yog los tswj DC motors tab sis nws kuj tuaj yeem ua tau siv tswj li qub, twj tso kua mis, hydraulics, thiab lwm yam khoom siv tshuab.

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