• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 30 subscribers
  • Views 332 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

PCM1794A: The drift

Hayashi
Expert 1840 points
Part Number: PCM1794A


Hi teams

Is there a document on the application relationship between 5 VA of power supply and output current?
My customer wants to know the correlation because the fluctuation of the power supply voltage is output as it is.
Also, if the power supply voltage is stable at + 5VA, is there any document that shows the drift characteristics of the output?
Best regards.
Hayashi
  • 0
    TI__Guru 55073 points
    Hi Hayashi-san,

    I do not have a specific document for these questions. The output magnitude for the different current segments are created by a bandgap reference that creates a reference current across the IREF resistor. This voltage is buffered internally, the output of which is decouple at the VCOM pins with external capacitors. Noise on VA will impact the output by coupling through those caps and through the PSRR of the reference buffers and (to a lesser extent) the reference itself.

    Drift can be expected through the reference. This would primarily impact the magnitude of the fullscale output, and I doubt it would have much impact on audio quality.

    Thanks,
    Paul