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LM48100Q-Q1: Audio cut-off when supply voltage drops from 5V to 3V

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Replies: 2

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Part Number: LM48100Q-Q1

LM48100Q-Q1's operating supply voltage is listed as 3V to 5.5V.

In customer's use case, they have a scenario when supply voltage drops from 5V to 3V. It was observed that LM48100Q-Q1 would cut off for ~3 seconds before resuming. Is this the expected behavior of LM48100Q-Q1? (That is would cut off the audio output during voltage dips, even within recommended operating conditions for supply voltage?)

LM48100Q-Q1 is used for an alarm, it is required to operate continuously through this voltage dip. Is there any way to overcome this problem?

Eddie Koh

Senior Field Application Engineer 

Texas Instruments Singapore

  • Hi Eddie,

    Do you have scope captures of the supply voltage when it drops to 3V? Perhaps the voltage is actually going below 3V causing this kind of reset.

    In addition, can you provide the schematic? Perhaps the decoupling capacitors on VDD/PVDD can be modified to provide a voltage headroom during the drop; a big capacitor would help to slow-down the drop slope, if there is a brief overshoot below 3V the capacitor could help.

    Best regards,
    -Ivan Salazar
    Applications Engineer - Low Power Audio & Actuators

  • In reply to Ivan Salazar:

    Eddie,

    Thanks for reaching out through email. I'll follow up with you offline.

    Best regards,
    -Ivan Salazar
    Applications Engineer - Low Power Audio & Actuators