I am developing a circuit that has as an input a line-level audio signal, it then boosts the signal using either an op amp or transistor so that line-level (which is around 1.6v) is boosted to what my MCU ADC input works best with, which is 3.3v
The problem I am trying to solve, is that the audio input signal will come from a phone, ipod or what ever, and each of these devices has its own volume control. But the end result I want is not related to the volume, I just want to have a signal that is optimally amplified what ever the volume.
Is there an IC that does this, or a circuit that can make this happen? I have ideas on what to do in the digital realm through code, but it would likely produce better results if I could solve the problem on the analogue side.