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PCM1820：What is the bias voltage of the audio input?

user1866475
Intellectual 350 points
Part Number: PCM1820 
Dear support team,

I confirmed that and thought that the bias voltage was around 1.5 ~ 1.45V.
Seems to be sufficient for full-scale input 2Vrms. 
The supply voltage of my system is 3.3VThe amplifier in the previous block is also 3.3V.That means that the amplifier output is up to 3.3V.
When a 3.3V signal enters the PCM1820, it first exceeds the specification of negative voltage limitation.
I suspect that the bias is not half the power supply. Since there is a 3.3V input under the worst conditions in the system, I would like to avoid breaking the PCM1820 low voltage limitation by halving the bias of the power supply. 
Is there a way to do that?

Best regards,
Yukio Oyama
  • 0
    TI__Genius 13610 points

    Hello Yukio,

    I am not sure what negative voltage limitation you are talking about but everything on the chip has voltage controlled by regulators that cannot be changed.

    What exactly is the issue you are running into?

    Best Regards,

    Low Power Audio Apps Team