I have a ramps 1.4 board which among other things, drives a 12V cartridge heater for the extruder hot end. The controlling arduino mega regulates the desired temperature via PWM through a simple mosfet driver.
I have connected a short (8 leds) LED strip to the board’s onboard 12V aux connector. The mosfet and the aux connector share the same 12V line which has basic filtration via a parallel 100uF/100nF arrangement.
The problem I have is that when the PWM algorithm is active the LED strip starts to flicker (I know this as the board has an LED to indicate power status to the heater output and it flashes when PWM is active). The LED strip flickering happens exactly and only when the onboard LED flashes.
I’m guessing the power supply capacitors aren’t quite up to the task? If so should I simply be increasing them, and what value would be appropriate? I’m also beginning to suspect this PWM ripple is also causing a couple of minor issues with the quality of my prints.