>>2921665
>LDO is going to be able to turn 3.3V into 3.3V filtered
yeah right, those caps were very retarded

>Presumably this is meant to be portable,
exactly
>make a list of all quiescent currents to figure out what's eating your power the most
is there an easy way to do this? Like software simulation or something?

>consider the noise and quiescent current implications of this compared to using a simpler single-supply design.
right. to be honest i kinda jumped on the first thing i found that was good enough, OPA1622 seems to have some pretty solid specs
regarding noise, thd etc: do you calculate these things with pen and paper?

>Why not use a button matrix instead of one I/O pin for each button?
that would be great, I need GPIOs
since the buttons are 9 < 2^4 ... is it feasible to encode them into 4 or 5 wires instead of 6?
may be a retarded solution idk

>why is your DAC all running on AGND even to pin 27?
true, that's bad.. now i have fixed it

>it might make edge cases like extremely low/high impedence headphones easier to handle without fault.
damn things seems harder than i thought