REGARDING THE DUTY CYCLE OF PWM

Discussion in 'General Electronics Chat' started by magnolias, Dec 3, 2008.

  1. magnolias

    Thread Starter New Member

    Dec 3, 2008
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    HELLO ,

    COULD ANYONE TELL ME /EXPLAIN HOW DOES THE DUTY CYCLE OF A PWM(DRV-101) VARY WHEN THE INPUT IS OF VOLTAGE LEVELS BETWEEN 0.75 AND 3.7V( THIS VOLTAGE LEVELS ARE FROM A VOL TO FREQUENCY CONVERTER VFC32).I WOULD ALSO LIKE TO KNOW THE AMPLITUDE OF THE RESULTANT PWM WAVE.

    THANKS IN ADVANCE
     
  2. Wendy

    Moderator

    Mar 24, 2008
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    It's the average voltage of the output. You filter out the AC, and you're left with the DC component.
     
  3. magnolias

    Thread Starter New Member

    Dec 3, 2008
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    THE OUTPUT FREQUENCY OF THE PWM IS AROUND 24 KHZ.....ANYHELP REGARDING THIS WOULD BE REALLY APPRECIATED
     
  4. magnolias

    Thread Starter New Member

    Dec 3, 2008
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    HELLO BILL,

    THANK YOU FOR THE REPLY ,BUT COULD YOU EXPLAIN THAT IN DETAIL BECAUSE I AM A BIT WEAK IN THIS.
     
  5. Wendy

    Moderator

    Mar 24, 2008
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    Many devices, like motors or lights, respond to the average power. I don't know anything about your basic circuit you are refering to, but PWM is basic theory.

    [​IMG]

    Visualize a RC circuit attacted to a PWM circuit, the red lines would show how the voltages would average.
     
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  6. Wendy

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  7. magnolias

    Thread Starter New Member

    Dec 3, 2008
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    Hello Bill ,

    I was actually referring to the circuit discussed in the following link.

    http://electronicdesign.com/Articles/Index.cfm?ArticleID=6168

    The link for the circuit diagram is mentioned in the above link but just in case i am sending you the link . Any help about how the o/p of vfc (which is sent as the input to drv 101) affects drv101 and the duty cycle .
     
  8. magnolias

    Thread Starter New Member

    Dec 3, 2008
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    Last edited: Dec 3, 2008
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