What is it?

MCP39F511 Breakout based around the Microchip MCP39F511 Energy Monitor ASIC suitable for breadboard use.

Why did you make it?

A friend of mine : Mike mentioned that he was using the MCP39F511 for work since it has very good energy measurement accuracy compated the mt ATM series I am most familiar with. So I decided to have a go at putting together an easy to use breakout at a 1/10 pricepoint compared the manufacturer devkit to drive greater adoption and experimentation with this ASIC. The shortcoming of this module compared to the full devkit is that it does not come calibrated and needs 12V transformer to use instead of AC mains.

What makes it special?

This module has been specially designed like all other energy monitor breakout in my collection to be breadboard friendly. The inputs are 12V AC adequately stepped down using voltage divider ladder, I recommend a 100K resistor in series with the 1k resistor on-board to act as the voltage divider and a 100A/50mA CT. With these as input sampling mechanisms the ASIC can be calibrated to produce energy readings over UART using the Arduino codebase here or Micropython codebase here. Additionally a 3.3v USB-Serial adapter can be used with this ASIC to use it directly from a computer or an ML platform like a Jetson.