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  1. #1
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    CURRENT MODE PWM BUCK DCDC output ripple!

    Can anyone tell me what the ripple looks like is a good design.
    Its like a ^^^^^^ or ~~~~~~?
    thanks.

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  2. #2
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    Re: CURRENT MODE PWM BUCK DCDC output ripple!

    The ripple in output voltage appears to be sinusoidal (output smoothing capacitor).. see picture below ..

    Regards,
    IanP



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  3. #3
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    CURRENT MODE PWM BUCK DCDC output ripple!

    Hello IanP:
    if you add the esr(200mohm) to the output cap.
    Its output ripple just like ^^^^, not sinusoidal.



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  4. #4
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    Re: CURRENT MODE PWM BUCK DCDC output ripple!

    Therefore I used the word "appears" not "is" ..
    In a "good design" you don't have just single capacitor as the output LPF, but there will be another L-C stage ..

    Rgards,
    IanP



  5. #5
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    CURRENT MODE PWM BUCK DCDC output ripple!

    Hello IanP:
    In a "good design" you don't have just single capacitor as the output LPF, but there will be another L-C stage ..

    You mean to add another L C filter at the output?
    thanks.



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  6. #6
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    CURRENT MODE PWM BUCK DCDC output ripple!

    does IanP mean the pi filter used as LPF?
    it is formed by a large capacitor, an inductor and another capacitor.



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