Because of the Thanksgiving holiday in the U.S., TI E2E™ design support forum responses may be delayed from November 25 through December 2. Thank you for your patience.

  • State Resolved
  • Replies 4 replies
  • Subscribers 64 subscribers
  • Views 91 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

TPS563202: Less efficient than datasheets

Ryu Yamashita
Expert 2490 points
Part Number: TPS563202

Tool/software:

Hi team,

I have measured the efficiency using a regulated power supply with the attached schematic, but it is only about 80%.
Is there any possible cause for this?

C511 GRM21BR61E226ME44K Murata
C512 GRM155B31H104KE14D Murata
C513 GRM21BR61E226ME44K Murata
C514 GRM21BR61E226ME44K Murata
C515 GRM155B31H104KE14D Murata
C516 GRM1552C1H220JZ01D Murata
L500 1255AY-4R7M Murata
Port input[12V] output efficiency[%]
current[A] power[W] current[A] voltage[V] power[W]
1 0.722 8.664 1.477 4.744 7.007 80.874
2 0.734 8.808 1.476 4.830 7.129 80.939

Best Regards,
Ryu.

  • 0
    TI__Genius 10510 points

    Hi Ryu,

    Please measure Vin, Iin, Vout, Iout by multimeter, do not read number from power supply and e-load. And please measure Vin and Vout on input/output capacitors. Thanks.

  • 0 in reply to Shipeng Cheng
    Expert 2490 points

    Hi Shipeng,

    Thanks for the reply.
    I measured the input and output with a multimeter.
    I also measured with the capacitor near the IC but the efficiency is still worse than the datasheet.
    Is there any possible cause?

    Port input[12V] output efficiency[%]
    current[A] voltage[V] power[W] current[A] voltage[V] power[W]
    1 0.733 11.458 8.399 1.476 4.804 7.091 84.426
    2 0.723 11.461 8.286 1.470 4.740 6.968 84.088

    Best Regards,
    Ryu.

  • +1 in reply to Ryu Yamashita
    TI__Genius 10510 points

    Hi Ryu,

    Based on your schematic, the Vout should be 5.28V but in your test the Vout is only 4.8V, could you confirm the FB voltage is 0.8V? And you can measure SW waveform to see if device works stable. Thanks.

  • 0 in reply to Shipeng Cheng
    Expert 2490 points

    Hi Shipeng,

    Thanks for the reply.
    I apologize.
    There was a diode in the measurement line that caused the bucking.
    After re-measuring, the efficiency was as per the datasheet.
    I apologize for the inconvenience.

    Best Regards,
    Ryu.