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TPS73801-SEP: PSRR Curve

Erin Yu
Prodigy 80 points
Part Number: TPS73801-SEP

Hi Mr./Mrs.,

Could you please help to prove the PSRR curve of TPS73801-SEP for our reference?

Thanks

  • 0
    TI__Guru 62930 points

    Erin,

    I have some lab time Wednesday, and possibly tomorrow that I can attempt to recreate a PSRR plot for you.

    Do you have specific conditions you would like to see?  Vin, Vout, Cout, and load?

    Regards,

    Wade

  • 0 in reply to Wade Vonbergen
    Prodigy 80 points

    Hi Wade,

      Thanks for your reply. For our application, TPS73801-SEPs are used for the conditions below. Maybe you can help to choose some representative conditions to show PSRR plot. If you have any suggestion about Cout to get better performance of TPS73801-SEP, please also advice. Thanks a lot!!

    Vin: +3.3V, Vout:1V, Cout=10uF, Load=300mA

    Vin: +3.3V, Vout:2.5V, Cout=10uF, Load=100mA

    Vin: +7V, Vout:5.5V, Cout=1uF, Load=50mA

    Vin:+7V, Vout:2V, Cout=10uF, Load=200mA

    Vin:+3.3V, Vout:1.9V, Cout=10uF, Load=500mA

  • +1 in reply to Erin Yu
    TI__Guru 62930 points

    Erin,

    Typically lower Vout will have better PSRR performance.

    Lower load will have better PSRR performance.

    Higher Vout capacitance will have better PSRR performance

    Will need minimum headroom to insure Vin ripple doesn't get within dropout region.

    I will not be able to test all of the above conditions in the near term as it is fairly time consuming changing board configuration.  Will also be subject to availability of appropriate components.

    BTW, the minimum Cout recommended is 10uF.  Your case 3 only has 1uF, but may be okay with such a light load.

    I have lab time tomorrow, and will target the last case of 3.3 vin, 1.9Vou, 10uF and 500mA.

    I will get back to you soon.

    Regards,

    Wade

  • +1 in reply to Wade Vonbergen
    TI__Guru 62930 points

    Erin,

    I was able to get PSRR data for the 3.3V Vin, 1.9V Vout, Cout = 10uF with various loads.

    The different plots are described by Vin_Vout_load(ma)

    Hopefully this gives enough data to resolve your concerns.

    If this answers your question, please click "This Resolved My Issue"
    Regards,
    Wade