Now, I am using ADAU1701 to design a Sound equipment.
I am going to make a function: when there is signal input, or adjust add the volume, then, ADAU1701 turn on a LED.
While there is no signal input ,or the volume is very low, turn off the LED.
May be the output pin didn't just drive a LED, but link to MCU, to wake up MCU from Sleep mode.
There is Signal input, the MCU working, while no signal,MCU go into sleep mode.
To light a led is no problen, using a gpio pin of output is ok.
But how to detect the input signal? Now I have no idea.
I used the RTA OUPUT, and Limiter , they seemed not OK.