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ADAU1401 with PCM5102 DAC, BCLK missing

Category: Hardware
Product Number: ADAU1401

UPDATE:

My scope was not good, later I managed to measure properly.

DATA, LRCK, BCLK frequencies+voltages from the ADAU ok.

But maybe i found what cause the issue:

PCM5102 voltage pins:

- pin 1 CPVDD: 3.3V

- pin 8 AVDD: 3.3V

- pin 20 DVDD: shorted to GND

- pin 18 LDOO: 0V

Is it ok that pin 20 shorted to gnd & no voltage on pin 18?

ORIGINAL QUESTION:

"Hi!

Im trying to use ADAU1401 DSP with PCM5102 DAC, but i have no sound from PCM.

Checking DATA, LRCK, BCLK with scope.
DATA ok, LRCK 48kHz but BCLK is 0V. 

What could be the problem?

Thanks a lot!"



My scope was not good, later I managed to measure properly.
[edited by: DarioRossi98 at 5:55 PM (GMT -4) on 25 Sep 2023]
  • Hello Dario,

    - pin 20 DVDD: shorted to GND

    - pin 18 LDOO: 0V

    Is it ok that pin 20 shorted to gnd & no voltage on pin 18?

    No, it is not going to work without DVDD and without the LDO output working. 

    Yes, you will need the BCLK to be working but also you will need to bring in a master clock. 

    You also did not mention who is the clock master? If the SigmaDSP is the clock master then it does not need an external master clock, it will use its own to develop the LRCLK and BCLK. 

    Dave T

  • I fixed the short circuit, wired 3.3V to DVDD pin but still no sound.

    • pin 1 CPVDD: 3.3V
    • pin 8 AVDD: 3.3V
    • pin 20 DVDD: 3.3V
    • pin 18 LDOO: 1.9V

    ADAU is the clock master, in SigmaStudio: "Master Mode". LRCK, BCLK frequencies tested with scope.

  • Hello Dario,

    This is now falling on how to get the DAC to work and I am limited to how I can support a product from TI. 

    It looks like it needs a master clock. I read part of the datasheet and the pin is called SCK and it is vague as to what ratio it is looking for or how to set it? It gives a range of 128-3072 x fs. That is quite a range. Usually I would expect it to be 256x fs. So you need to supply it with a 12.288MHz clock if you are running at 48kHz fs. Make sure the mute pin is not activated. The datasheet is not too big so look it over carefully and it might give you a hint as to where the problem is. Form what I see here you are still missing one clock.

    Dave T