Dear TI Community,
I'm facing with a problem using TAS5756M.
Sometimes, at power on, in a random manner, after I2C initialization and speaker mute activation, I can ear a digital noise coming out from the loudspeakers, whose intensity changes by temperature variation. This means that if I make the TAS5756M colder by "dry ice" spray, the noise greatly reduces, but it comes out again soon as the temperature rise up again.
The MAX temperature reached is not so high and it is about 74”C on the body of the TAS.
I have used a heat sink, but the random noise is still present.
I tried to use ldo regulators for the AVDD and DVDD with better noise performance (like the TI LP2989AIM-3.3) but it doesn't solve the problem.
The AVDD and the DVDD are generated by a low noise ldo regulator starting from an input voltage of about 12V ( this is a clean analog voltage used for the audio path).
The PVDD is derived from the output of an ac/dc wall adapter (24V 2.5A)
Maybe someone has experienced the same problem and can suggest improvements in order to avoid the random digital noise.
If it is possible I would like to revise the schematic with some TI application engineer, but I don't know how to do.
Thank you very much in advance for your help and cooperation.
Best Regards,
Diego Ferraiuolo