What is it?

ATM90E26 breakout for AC energy monitoring. It allows development of code and applications conveniently.

Why did you make it?

I wanted to test various energy monitor ASIC's. I have already made an ADE7763 Breakout, I wanted to try the ATM90E26 for comparison and ease of use (SPI/UART alternatives). However it is not cheap since ATMEL's version of the EVM is too expensive, aimed at the enterprise rather than electronics hobbyists.

So I took the low voltage parts of the reference design and made a breadboard friendly breakout.

What makes it special?

Accurate and well documented Energy Monitor chip in a breadboard friendly package which can be combined with any popular microcontroller platform with a SPI bus.

I have tested the SPI code with Teensy, ESP8266, Arduino M0 and Particle, but the Arduino code should be portable to any compatible platform that supports SPI Mode 3. This code was ported from a RaspberryPi version by Ryzee, the Pi is also supported.

UART code has also been tested with the ESP8266 and this is the recommended platform for building Wifi Energy Monitors with the ATM90E26. The ESP8266 does not support SPI Mode 3, but it is misrepresented as SPI Mode 2.

Note on Usage

Build a low voltage test circuit using signals smaller than 600mV RMS. Typically with a voltage divider hooked up to a 12V transformer. Do not connect high voltage AC to a breadboard.