• State Resolved
  • Locked Locked
  • Replies 6 replies
  • Answers 1 answer
  • Subscribers 29 subscribers
  • Views 2760 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

Searching for XLR ADC

daniel
Genius 5095 points
Other Parts Discussed in Thread: PCM2902C, PCM2903C, PCM2906C, PCM2912A, PGA2500

Hi Team,

Please kindly help to suggest the right solution for XLR ADC.

Customer also request to control ADC input volume by a VR knob.

Any reference design for this application?

Thanks

  • 0
    Genius 5095 points

    Hi Team,

    Add the block diagram.

  • 0 in reply to daniel
    TI__Mastermind 30120 points
    Daniel,

    One important question would be if they need UAC 2.0 compliance. We have a few USB2.0 compliant USB codecs, but they are all UAC1.0 only.

    best regards,
    -Steve Wilson
  • 0 in reply to Steve-Wilson
    Genius 5095 points

    Dear Wilson,

    Thanks for your support.

    UAC1.0 is fine. Could you give use suitable ADC suggestion?

    We want to adjust both XLR mic and 6.5mm mic input volume, then switch one of them to USB output.

    Thanks

  • 0 in reply to daniel
    TI__Mastermind 30120 points
    Daniel,

    You can take a look at the following devices:

    PCM2902C
    PCM2903C
    PCM2906C

    none of these devices is going to be a perfect fit but there are 2 ADCs in each one.

    The PCM2912a has integrated PGA for its single input, but that obviously wont work for you.

    best regards,
    -Steve Wilson
  • 0 in reply to Steve-Wilson
    Genius 5095 points

    Dear Wilson,

    Many thanks for your suggestion.

    Now we survey PCM2906C, there are some design questions need your help.

    1. XLR signal is Positive & Negative , But reference circuit MIC in is R/L. So P connect to R, N connect to L, right?

    2. VR volume control should be placed before OP or after?

    Thanks

  • 0 in reply to daniel
    TI__Mastermind 30120 points
    hi Daniel,

    You don't have to use the same circuit as the EVM. The EVM doesn't have an XLR connector, honestly the only ADC EVM that does are the PCM4xxx devices. Those are designed for Professional audio use.

    You will need to take the differential signal and convert it to Single ended. Opamps are obviously a good choice for this, regarding volume control, there are many options, you can do something passive, or you could consider something active. its really up to you.

    check out the PGA2500 for a digitally control microphone amplifier.

    best regards,
    -Steve Wilson