Hi Support team,
MAX98089 datasheet shown the THD+N can support around -80dB for all audio band, we are trying to test it from EVK and provide 48K audio from the AP.
But we cannot get the THD+N under -80dB as well, could you help to review the file and give some suggestion to improve THD+N performance?
Hello, JustinWu_Ans,
When the performance is so much worse than what the MAX98089 is supposed to deliver, there is usually something misconfigured or there is a problem with the I2S DAC inputs.
I have just quickly checked the performance of my MAX98089 EVKit compared to the datasheet TOC plot in the middle of page 47, and while my plots are not identical, they are closer than what you are seeing. My test cables and loads are not optimal, so this performance could be improved.
The first place that I would look for problems would be the I2S signals. Ensure that they are using the same voltage level as VDVDDS1 and VDVDDS2. The part may appear to function when the I2S signals don't match the S1S2 voltages, but the performance will be degraded.
Also make sure that the DAI input is formatted correctly. If you are using I2S delay or not, make sure that the MAX98089 is configured properly. A mismatch in this configuration will also cause poor performance.
If you can capture an FFT of the HP outputs, it might provide more clues as to what is causing the poor performance.
If you are able to attach a control register data dump to a reply, I can look it over and see if there is anything that stands out to me as being misconfigured.
