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[PCM5102-Q1] DC output capability?

Other Parts Discussed in Thread: PCM5102-Q1, PCM5122, PCM5102, PCM1794A

Hi,

Can the PCM5102-Q1 Audio DAC generate stable DC output? In the intended application, we need a variable frequency (DC to 10kHz) sinus output.

Thanks for your help!

Best regards,

Matthias Prinke

  • Hi, Matthias,

    Welcome to e2e, and thanks for your interest in our products!

    I have asked my colleague to respond to your question.

    -d2

  • Hello Matthias,

    thanks for getting in touch. The PCM510x by default integrates a high pass filter. Any DC on the signal is seen as a DC offset, and within the target application, potentially damaging to devices further down the signal chain (such as amps and speakers). It is filtered out digitally inside the DAC.

    However, on the PCM5102's big brother, the PCM5122, the high pass filter can be bypassed. 

    Please note that DC accuracy/drift etc is not tested on these Audio devices. While the device would be able to output the DC signal, it's accuracy etc would not be guaranteed by test/design.

    Thanks again

    Dafydd

  • Hello Dafydd,

    thank you for the quick and helpful reply! It seems that the PCM5122 does not really fit for our application. In addition to the DC output issue, we might encounter more effort than expected on the software/configuration side.

    Maybe you can recommend another device which meets the following specifications:

    - Operating conditions/temperature range: Industrial or automotive

    - Digital interface levels: 3.3V

    - digital data interface: serial or parallel interface to DSP (Analog Devices Blackfin BF537) 

    - Sample rate: 48 kHz, 96 kHz or higher (not necessarily typical audio sample rates)

    - 2 channels (parallel output of samples)

    - Resolution: >=16 Bits

    - Output: Ground centered,  2V_rms (extra amplifier would be acceptable), stable DC output

    - Supply: single supply (3.3V or 5V) preferred, symmetric supply (+/- 12V) acceptable

    - package suitable for prototyping (reflow soldering, non-BGA or similar)

    Thanks in advance for your help!

    Best regards,

    Matthias

     

  • Hi Matthias,

    please look on the PCM1794A. It has special Digital filter bypass mono mode. it can be interesting for you. However PCM1704 is probably better thanks to his R-2R construction, but it is not manufactured any more.

  • Thanks, Pavel!

    Matthias, in addition to Pavel's recommendation, I think PCM5122 is really your best bet. We can re-qualify it to -Q1 if you require, please contact your local TI Sales Office for more information on how to get that process started.

    -d2