I am struggling to find an answer in the manual for the ADAU1979 to the following question:

How is the actual voltage calculated from the ADCs output?

I am used to the following equation

Voltage = conversion_value * V_ref / 2^(resolution-1)

However, with the fixed V_ref of 1.5V this equation does not work.questions regarding ADAU1979 says it is the 1.5 V reference

I cannot find an equation in the manual. Can you help?

Hello Jakob,

The ADAU1979 has full scale input of around 4.5V rms differential typical. So your equation is not considering this fact. I think you would need to add approx. 12dB to the above equation to account for this.

What is the input voltage in your test?

Also note the sensitivity tolerance is around +/-7% from typical.

Regards

Rajeev