I'm making a fan controller for my PC based on the Atmega328p microcontroller (basically an Arduino Nano). MY problem is that I want to control 6-8 fans independently but the chip only has 6 PWM outputs and I can only adjust the fr4equency f 4 of them.
I've tried to use some PWM expander over I2C but I cannot find one that can go up to 25kHz. (the standard PWM frequency of 4 pin PC fans)
Do you have any suggestions to solve my problem?