PCM5101A: Question of PCM5101A THD+N and Frequency Reponse

Wayne Chen (Audio AE)

Part Number: PCM5101A

Hello Sirs,

Would you pls assist us to review if the PCM5101A's THD+N and frequency reponse curve make sense? We sent the I2S signal to the PCM5101A chip by Audio Precision equipment directly and measure its output with no any filter. Is it doable to have 100dB THD+N and flat freuqency respnce with +/-0.25dB ripple on both ends?

Thank you and Best regards,

Wayen Chen
12/20/2016

over 8 years ago

0 Luis Fernando Rodriguez S. over 8 years ago

TI__Guru* 84915 points

Hi, Wayne,

Both plots are in order. They show a typical behavior of the PCM5101A. Regarding the THD+N plot, the THD+N level can improve if an output filter is placed as described in the Electrical Characteristics section of datasheet ( www.ti.com/.../pcm5101a.pdf ).

Best regards,
Luis Fernando Rodríguez S.

0 Wayne Chen (Audio AE) over 8 years ago in reply to Luis Fernando Rodriguez S.

TI__Genius 15950 points

Hello Luis,

With FLT connected to GND, the passband should be 0.45fs = 0.45 * 48kHz = 21.6kHz flat, however, the passband drops at 1kHz with 48kHz LRCK, 3.072MHz BCLK and 12.288MHz MCLK. Would you please advise if there is missing with my calculation? Do we have another I2S DAC to achieve 20Hz~20kHz flat at +/-0.25dB?

Thank you and Best regards,

Wayne Chen
12/21/2016