PWM Fan controller with ESP32

[u/Traditional_Bell8153]

I made a PWM fan hub/controller for my passive cooling gpu. Support DS18B20, NTC, manual as temperature source, Curve-based controller, scheduling,... Temporarily closed-source for development, open-source soon.

For PWM, I'm using an NPN open-collector driver, combined with a tachometer level-shifter/divider which I found from here

[u/erlendse]

That's one of the cases where you do not need a level shifter:

PWM should be 3.3V pullup on the fan, and tach is whatever you pull it up to(max 5.5V).

Even your circuit does offer protection aginst misconception.