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  1. #1
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    Offline BCM Flyback SMPS means low secondary diode snubber loss

    Why is it that none of the App notes on offline BCM Flybacks actually state that a major reason for going BCM, is that you avoid CCM….and this means that the losses in the secondary diode snubber resistor can be far less. This is especially true when you have a low turns ratio NP/NS

    https://www.fairchildsemi.com/applic...AN/AN-6093.pdf

    ..as you can see, the above, or any others, make no mention of this....why?

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  2. #2
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    Re: Offline BCM Flyback SMPS means low secondary diode snubber loss

    The major reason for using DCM or BCM is the avoidance of RF noise, largely created by the o/p diodes when they are hard switched in CCM...

    CCM has lower RMS currents - but is an EMC headache ...


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