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UCC28019A: for AC24Vin

Guru 10180 points
Part Number: UCC28019A

Hello E2E,

Our customer are considering using the UCC28019A for AC24Vin block on during to developing equipment. I obtained the capture of schematic from them. Could TI engineers check this schematic?

Best regards,

  • Hello ACGUY,

    It is unusual to use the smart diode controller LM74670 and synchronous rectification on a pfc stage.
    The very low input impedance into the large bus capacitance may cause a very large inrush current at start up  and failure of a component
    unless some inrush protection is added to the pfc.
    I think a startup resistor is required to pre charge the output capacitors.
    Normally you would short out this resistor after a pre determined time and then enable the pfc.
    The design should give excellent efficiency but it needs to be protected from transient conditions.

    Im not sure what value of inductance is used but it needs to be 160uH or greater for this application.

    Those are my only comments.

  • Hello John,

    Thank you for your comment. About settings RC value, does this schematic have any mistake?

    Best regards,


  • Hello ACGUY,

    I did not see an error in any component value or have any more suggestions or comments.