TAD5212: Noise of TAD5212 DAC During Power-On and Sampling Rate Adjustment

Part Number: TAD5212


I have completed the initialization of TAD5212 according to the configuration shown in the figure.
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Currently, two issues exist:
 
  1. When the last configuration command "w a0 78 40 # Power up DAC channel" is executed, the DAC will produce a brief popping noise.
  2. After the initialization of TAD5212 is completed, adjusting the I2S sampling rate will also cause the DAC to generate a brief popping noise.
 
Is there any method to eliminate this instantaneous noise?
  • Hello, we have received your case and the investigation will take some time. Thank you for your patience.

  • Pop noise a common issue in many of DACs and usually it happens during PU and PD or when clks are changed or become invalid.  Usually a pop noise is due to abrupt charge or discharge of capacitor at the output node which happens at power up and power down. Also  a sudden interruption of the I2S clks would cause a pop noise at the output. 

    In many of our DACs , we have a soft mute option that we engage it before clk or power changes. TAD5xxx family are pretty good  in pop noise suppression and even the SW version can adjust some timings to de-pop via some registersTAXD5xxx family have a unique feature to remove the pop noise or reduce it based on some settings or requirement.

    Register 0x6 (DAC_CFG_A0) is the   de-pop configuration register

    Or when DAC_ST_W_CAP_DIS ( Register 0x07)  is enabled, it enables quicker discharge of the capacitors by internally pulling the OUTP/M pins to GND and that can help the pop noise . The duration for this is determined by the PWR_UP_TIME_DE_POP setting in register 06.

    So you have to use these knobs to reduce or remove the pop noise.

  • Thank you for the method you provided; it can indeed reduce pop noise.