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    Formula for feedback loop (power stage & modulator) of full bridge with LC filter

    Referring to Basso book page 227 , equation 2A-7, if after my upper divider resistor I have an LC filter and then the load resistor, do I need to put the load “R” parameter in as a complex parameter incorporating the output LC filter too

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    Re: Formula for feedback loop (power stage & modulator) of full bridge with LC filter

    Yes, especially if the filter has a resonant frequency that isn't far above your intended crossover frequency.



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    Re: Formula for feedback loop (power stage & modulator) of full bridge with LC filter

    But Basso doesnt say to do this, so why do you speak of doing this?

    Basso on p.685 just says we must arrange smps crossover to be at least three times less then the output LC filter resonance frequency.



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    Re: Formula for feedback loop (power stage & modulator) of full bridge with LC filter

    Quote Originally Posted by grizedale View Post
    But Basso doesnt say to do this, so why do you speak of doing this?

    Basso on p.685 just says we must arrange smps crossover to be at least three times less then the output LC filter resonance frequency.
    If the LC resonance is three times the crossover, then, as I said, it's not too bad. But it may still be relevant to the transfer function below the crossover frequency, depending on the relative capacitances of the output filters. Hard to say without actual values and a schematic.



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