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UCC28063A: About UCC28063A Application Question

Part Number: UCC28063A

Hi Sir,

My customer plan UCC28063A design 600W SMPS.
Currently has MOSFET damage when start up PFC. I think is noise interfere control card(UCC28063A), since we use wrap up inductor with copper and wire to GND. improve MOSFET damage issue, but issue still occur at VAC 90V input.

Below is my customer schematic and PCB file.  Can you help review or recommend as below layout placement? thanks.

ATS600-P050 _ Power Board.pdf

ATS600-P050 _ IC Board.pdf


  • Hello Kuo Duke,

    The schematic shows a short across the overcurrent resistors (R14)
    Is this correct?

    Also I notice is that the power section has no series resistors on the MOSFET gates.

    These are located on the plug in control card. Normally R42(R47), R34(R46) and D13(D15) are located close to the MOSFETS

    This is to prevent noise pickup and parasitic high frequency oscillations on the gates. To see if this is a problem you could cut the trace on the gate and insert a small (10 Ohm) resistor on each gate.

    The failures are occurring at startup so perhaps the MOSFETS are turning on during the inrush time.

    Also you could add a 10uF cap on pin 6 of the connector CON10. Follow this with a 10 Ohm resistor and a 1uF ceramic on VCC of UCC28063A

    Sometimes noise can enter the controller through VCC

    Hope this helps


    John Griffin

  • Hi John,

    Thanks for your recommend. Check R14 is ok and I'll verfication gate resistor. thanks.