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PMP40871: Generating 48V directly only TPS61391

Part Number: PMP40871
Other Parts Discussed in Thread: TPS61170, TPS61391, , TPS7A4101

Hi support team,

I used to generate 48V of phantom power with TPS61170, but I am considering TPS61391 because the delivery time is bad.
The PMP40871 is equipped with the TPS7A4101 in the subsequent stage.
Is it possible to generate 48V directly with TPS61391 and use it as phantom power without the LDO in the subsequent stage?


  • Hi Dice-K,

    The TPS7A4101 is used here to reduce the output voltage ripple which is a key requirement of phantom power, you can see the output ripple of Boost stage in test report of PMP40871, if it meets your requirement then you can remove the LDO. Thanks.

  • Hi San,
    Thank you for your reply.

    I checked the waveform of TIDT235.

    Figures 4-1 to 4-8 show the waveform of TPS61391 and output about 48.2V.
    Figures 4-9 to 4-12 show the waveform of TPS7A4101 and output about 47.6V.

    I was confused because the titles of the Figures are all 48V.

    Best regards,

  • Yes, Fig.4-5 to 4-8 are output ripple of TPS61391 which average DC is 48.2V, then the voltage input to LDO and Fig 4-9 to 4-12 are output ripple of LDO stage. You need to check Fig 4-5 to 8.