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  1. #1
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    Buck Converter distortion

    I am using the following sch (Reference only)

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ID:	155318

    and i am getting the following pulse at the point shown in sch

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ID:	155319

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ID:	155320

    Why am i getting the variation before the start of ON Cycle. What might be causing this?

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  2. #2
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    Re: Buck Converter distortion

    all normal for light load - where the current is not continuous in the inductor, i.e. you are in DCM rather than CCM ...



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  3. #3
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    Re: Buck Converter distortion

    Yes, when the diode goes off, the diode voltage suddenly collapses from abotu 0.7v to zero, and its klind oif liek a step input, and the buick inductor then rings in the loop comprising the output capacitor and diode, as well as through the output cap and the input source capacitance.
    Your question is a regular one on all forums.....most askers are asking how to snub it out because they fear EMC...but it should not be snubbed.



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