Smoothie question… been up for too long that my brain hurts… if I have common ground for smoothies 5v connection to the laser psu do I need to use the ground pin associated with pin 2.5 for my pwm?
I would think yes. I just have a single ground to the psu through those blue wires you cut (this powers my board) and then I just run pwm to the IN on the psu. That’s it. All grounds should be connected, because that’s better than electricity needing to go somewhere and having to take a different route.
I power my smoothie from the laser psu’s main power connector: the 4 blue wires with the big white connector. My board creates 5v by itself so it doesn’t need that 5v from the potentiometer connector (3 pins: Gnd, IN, 5v). Level shifted pwm output from the board goes to the IN pin. Nothing else. (Just the LO to a MOSFET to fire the laser).
So you hijacked the IN from the pot but it’s still usable?
I want the Pot functional still for on the fly adjustments and current limiting
Then you can’t run the Input as PWM… unless you put in an SPDT switch to select between PWM control or analog control.if you run them both together you’ll have conflicts when it comes to current control.
The POT outputs a voltage between 0-5v.
"PWM or “Pulse Width Modulation”, sometimes called “Pulse Duration Modulation”. Magnitude being the TTL voltage level (5v). Recommended frequency for my power supply is 20khz. The percentage of “on time” controls the power supply output. 0% resulting in zero milliamp output and 99% resulting in maximum milliamp output. "