How to use a PWM input
I had intended to use the dimmer wire from my Dynon HDX to control when the the Blink Marine keypad dims, but it turns out to not be the 0-5v or 0-12v variable voltage that I expected. But instead,
"The DIM OUTPUT signal is an approx. 120 Hz Pulse Width Modulation (PWM) signal directly proportional to the screen brightness - 100% to 0.02%. This output is designed to directly control the dim level of devices such as LEDs; a common use is for the back-lighting of switches in a panel so that they dim at night in conjunction with SkyView’s automatic dim levels.
The DIM OUTPUT (Pin 26) signal is an open collector to ground - it acts as a switch to ground, and does not source any power itself. Pin 26 can sink a maximum current of 120mA and a maximum voltage of 40V. The DIM OUTPUT signal is not analog and cannot be used to control the dim level of devices that expect 0-5V, 0-12V, or a resistance as their dimming input."
Is this something I can run into the PDM? Am I making it more complex than it is?
Whipped up the circuit, which gives me a ~1v to ~12 volt output as the display sweeps though its brightness range. I think this will work perfectly. Thanks so much for taking the time.