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TIDA-01501: TIDA-01501 efficiency clarity

Part Number: TIDA-01501

HI Sir

I Apply the two evb, UCC28180,UCC25630 to combine a AC-DC

But the total efficiency is bad ,should i add extra circuit?

TIDA-01501 show the good efficiency ,please advise it.thanks

  • Hi Alex,

    For the efficiency improvement, please check the PFC efficiency and LLC efficiency separately, and check which dominates the efficiency bad.

    In TIDA-01501, the LLC efficiency is near 96% at full load, and the PFC efficiency is near 96.8% at 115Vac/full load, 97.5% at 230Vac/full load.

    About the LLC stage, it uses SR-FET as the secondary rectifier. Please check the LLC EVM use SR-FET or not. It is related seriously with the efficiency.

    About the PFC stage, could you check use low-cost SiC diode as the PFC diode due to the large reverse recovery loss resulting from CCM topology? 

    Besides, for the efficiency bad checking, you can use thermal imager to check which component is the hot spot, and then you will know which causes the efficiency bad.

    Hope my suggestion could be helpful for you.

    Thanks!

    BR

    Liu Cheng

  • Do you have the test report for no load as power effiecieny
    thanks
  • Hi Alex,

    In TIDA-01501, the circuit structure is CCM-PFC + HB-LLC + TIDA-01503(Auxiliary Power Supply).

    TIDA-01501 is expectedly for PC PSU application, so there is TIDA-01503 which is used to produce 5VSB and auxiliary voltage for primary side and secondary side.

    For no load condition, the power consumption is from the above three circuit, and the power consumption is mostly from the CCM-PFC.

    Also, the total power consumption is about 500mW for 230Vac.

    If you have any question, please let me know.

    Thanks!

    BR

    Liu Cheng

  • How the improve the efficiency in light load for UCC28180?

    i can'see the skip mode in no load, please advise it,thanks

  • Hi Alex,

    Yes, there is no skip mode in UCC28180. Even if in no load, the switching frequency is fixed at the setting value.

    If you want to improve the efficiency at light load, you can try to disable the PFC stage at light load, and you can make the standby power circuit to replace the main power output if you have the 12VSB circuit.

    Although, what is the power level of your design? UCC28180 is CCM-PFC controller which is used in high power application.

    Usually in high power application, there is no critical specification for light load condition.

    Thanks very much!

    BR

    Liu Cheng