In this project, I show you my approach to making a rotary encoder module.

One can buy different rotary encoder modules on Aliexpress for a very cheap price, and I have been doing that for years, too. However, I wanted to come up with my own version of such a module. Typical modules either only contain some pull-up resistors, or they even have RC low-pass filters, but I haven’t encountered any that have a built-in Schmitt trigger circuit that allows to produce perfect square waves.

Probably many people would say that one could debounce a rotary encoder with software, but I wanted to avoid it as much as possible and provide the microcontroller with an as clean as possible signal. Maybe it is an overkill, but I had fun designing and assembling the circuit and I also learned more about the components used in the circuit.