PIDuino – An Ardiuno PID Controller

An Arduino based PID controller designed for use within my Gaggia Classic Coffee machine but also for a water bath for sous vide cooking.


  • RTD100 temperature probe input with built in amp.
  • 3 relay outputs.
  • support for a nokia 5110 LCD or an SPI display.
  • Rotary encoder and 3 button input.
  • 1 LED output.
  • RTC with battery backup.
  • ATmega368.

Board Preview

Top of the PIDuino Board v1.0.4

Bottom of the PIDuino Board v1.0.4

Current Status

Currently I have just sent off the order to and I am looking forward to the PCBs arriving. I have already ordered most of the parts from digikey.

Design details

The project has been designed using DipTrace. Having tried eagle many years ago and having a quick go with both Eagle and Diptrace recently, I decided to go with Diptrace. It seemed better designed and the cost free limits involved seemed a lot more reasonable.

Warning: This is the first PCB I have designed for production and being mainly a software guy there may well be problems with it or bad techniques used. But I have to start somewhere!


PIDuino Software


This is an Open Source Hardware project so you can freely download and use the files etc… I would really appreciate an attribution though.

PIDuino Schematic v1.0.4 (PDF)

PIDuino Gerbers v1.0.4 (ZIP)

PIDuino Diptrace Src v1.0.4 (ZIP)

Fork me on GitHub