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TPS23751: Controller Design Tool

Part Number: TPS23751
Other Parts Discussed in Thread: LM5155, PMP20220, PMP11254, TIDA-00617, , TPS23754, TPS23752, TPS23756, PMP22301

Tool/software:

Hi,

Is there a design calculator (Excel) which can help in the design, like the one you have for LM5155/56?

Thanks,

Matan

  • Hi Matan,

    There is one calculation tool as attached.

    TPS2375x Design Workbook for TI.XLSX

    Besides, you can google search or in TI.com search TPS23751EVM, PMP20220, PMP11254, TIDA-00617 for TPS23751 related reference designs. 

    Best regards,

    Diang

  • Hi Diang,

    It seems there are some fields that are wrong or not aligned with the datasheet.

    For example:

    1. Switching frequency is determined by Fsw=8.5e9 / RT, and not as the formula in the spreadsheet.

    2. I couldn't find any reference in the datasheet for Rblank.

    Can you please re-check if there is an updated/newer version?

    Thanks,

    Matan

  • Hi Matan,

    Thank you for your quick reply. 

    This TPS2375x excel looks only applicable for TPS23754 & TPS23756, and it is not work well with TPS23751 & TPS23752. Just checked our resource but we do not have excel for TPS23751 & TPS23752. Sorry about that.

    It may be better to let us know your design target then we can help to find suitable reference designs for you. 

    Best regards,

    Diang

  • Hi Diang,

    My design target is PoE+ (using isolated flyback).

    Vin=52V

    Vout=24V/1.1A

    I found the PMP22301 which uses TPS23754. I would like to use TPS23751.

    I assume many components will be the same.

    Can you please indicate the most suitable starting point? Which components values can be taken to my target design?

    Thanks,

    Matan

  • Hi Matan,

    Thanks for your information. For flyback converter design, the biggest difference is TPS23751 has VFO mode, which lower the switching frequency at light load (for this design purpose, their switching frequency calculations are different). If you want to disable VFO, you can start with PMP11254 and I will send you the PCB design file. 

    You can replace PMP11254 's cycled circuit with PMP22301's circuit.  

    Below is the difference between 51 and 54. Let me know if you have further questions.

    TPS23751/2 (PD + PWM controller):
    -              Compliance to IEEE 802.3at
    -              0.5-Ohm typ. hotswap
    -              Flyback with secondary side regulation only (no internal error amplifier)
    -              Sleep mode (disable DC/DC, TPS23752 only) and high efficiency light load mode (automatically reduce switching frequency at light load)
    -              Support adapter priority

     TPS23754/6 (PD + PWM controller):
    -              Compliance to IEEE 802.3at
    -              0.5-Ohm typ. hotswap
    -              TPS23754 has 15-V Vc UVLO; TPS23756 has 9-V Vc UVLO(used for low-voltage DC adapter case).
    -              Both support flyback/ACF-active clamping forward (no internal error amplifier for both)
    -              Support adapter priority & low voltage PD input

    Best regards,

    Diang