I'm looking for a way to digitally modify the gain of an amplifier/DAC/codec in very precise intervals (0.1-0.2dB). My current process involves generating a sine wave with a DAC and then running it through an audio amplifier before playing it on a speaker. I wish to digitally adjust the gain of either the DAC, the amplifier, or some other portion of the circuit.
Practically all of the class A/AB/D audio amplifiers I've looked into have step sizes of 0.5-1dB. After inquiring at Texas Instruments, an employee recommended a codec with miniDSP/Class D amp (TLV320AIC3263), which does meet my requirements (0.1dB/step). While this is probably my best option so far, it's a bit outside of my scope and I feel there may be a simpler solution.
Can you think of any alternative ICs that meet these specs or this type of codec the best approach?