How to figure out cutoff frequency using scope for LC filter post SMPS

Discussion in 'The Projects Forum' started by witssq, Mar 19, 2011.

  1. witssq

    Thread Starter Active Member

    Mar 29, 2009
    48
    0
    I am using commercial SMPS +5, +/-5V output.

    Against SMPS output, I applied LC filter, and achieved 45mV noise down to 20mV noise, but I need about 5mV or below.

    Please anyone help me about how to find cutoff frequency not easy to figure out

    The microscopic view is after currently filtered.


    Best regards,
    SunSung
     
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