[MisterTea]

Yup. You could use a quad opamp to build a PWM controller with closed loop control but then you need all the passives to setup the oscillator and so on.

I went through this years ago making a fan driver for my vehicles HVAC blower. The analog setup was fun to make but you use more board space, higher BOM count, and really, higher BOM cost vs a micro-controller.

[fragmede]

It's crazy how far technology has advanced. A μc with RAM and a bunch of input and output ports and some code is cheaper today than a pile of analog components.