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PTH12040W: PTH12040W-Enq: Minimum external input capacitance required

Part Number: PTH12040W


For my application i am using PTH12040W 2 nos for (12 to 3.3 @40A  and 12 to 5V @30A) ,I want know the minimum external input capacitance that i need to sheet it is mentioned as 560uF,Kindly request to suggest the minimum input capacitor value for my requirement.

thanks regards


  • Kindly provide the switching current details  at the input node for the above mentioned converter

  • Hi Shiju,

    As you mentioned, the minimum input capacitance required is 560 uF. Note, that the capacitors required are recommended a minimum voltage rating of 2 x (Max DC voltage + AC ripple) and a RMS ripple current rating of 300 mA.
    For the 12 V to 3.3 V @ 40 A application, about a ~12A input current is required.
    For the 12 V to 5 V @ 30 A application, about a ~13A input current is required.

    Below, I've listed two Application Reports in which I believe can be beneficial when selecting an input capacitor: