I have heard the arduinos analog outputs are PWM signals simulating variable voltages by changing the duty cycles, rather than an actual varied voltage. I haven't seen this specifically addressed in the sources I've read and I don't have an oscilloscope to verify.
I find myself in need of more PWM outputs to control my 4 RGB LEDs. My Nano has 6 digital PWMs and 8 analogs, leaving room for two control potentiometers. If I can use those analog pins as PWMs, that would work out perfectly!
I have considered using an IC for expanding my outputs, I have some TLC5940s, but I'm using several LEDs in parallel and it wouldn't be able to handle the current without transistors. I have limited space on my board, so it's ether transistors or IC, not both. I don't have time to order the right ICs and transistors, I'm stuck working with what I have because of my tight project deadline.
Will I be able to use the analogs as PWMs? If not, I plan on using what I think is called bit banging to make up for the lack of PWMs.