I have an RC/drone ESC that takes a PWM input signal at 3.3 V/5 V for throttle control, but has no onboard buck/BEC. I have the illustration below for my current setup.
This motor works excellent with a VESC ESC/controller that has an onboard BEC/5 V but I want to try it without a software-enabled controller. Currently, with the setup below, the ESC triggers an intermittent beep sound every second, which according to the manufacturer is the troubleshooting sound for lack of receiver signal detection. Even following the instruction to set up the throttle, it does not detect. I have checked the voltage at the signal and the POT is properly outputting a range of 0-4.9 V.
Now, my hunch is the fact that the ESC requires a PWM input that is in the range of 50-500 Hz, where the DC buck I have is at 300 kHz for its PWM. Although the POT is working properly, I assume the frequency is far too high for it to detect. I do need to use this setup, as I am using a trigger/spring actuated potentiometer which is hard to come by on existing controllers. Ideally I want to be able to control the throttle with my spring POT and DC buck.
Questions:
- Do I need a special servo motor controller to behave as the PWM signal for the ESC?
- Can I use a DC buck that outputs the proper frequency?
- Is there a simple PWM generator I can use with my setup? Or a way to reduce the frequency?
- Is my assumption incorrect here and should the buck be able to output a proper signal?
Please let me know if I am missing something here. This is going to be for a production product so we need to use a specific setup, cost, sourcing, etc.