Injecting a communication signal over DC power supply lines
I have a pretty simple circuit, but I need to send an output PWM signal through the same place I'm getting my voltage. The voltage is DC, so I figure since my PWM is an AC current, I can use a low pass filter to send the signal through, while getting DC current from the supply. I'd prefer to use a capacitor/resistor filter rather than an inductor, but I'm unsure how I would go about creating one for this particular circuit. My problem right now is that the AC signal goes back to VCC rather than to my AC Input (that also supplies my power).
For an inductor, I'm guessing I'd put it on the path to VCC of my microcontroller? Where would I do it with a capacitor?