Migration from INA226 to INA3221

A project log for Luke - Open Framework Multimeter/Logger

DMM dedicated to PC/smartphone with cross platform SDK provides user-friendly measurement and automation system

MaxMax 05/23/2016 at 15:180 Comments

I decided to change a power monitor IC from INA226 to INA3221, that is a 3ch current monitor, based on the discussions with a talented engineer on this page. Although ADC native resolution is downgraded from 16bit to 13bit, measurement range of voltage is expanded and auto-range select is supported for both voltage and current measurement. Auto-range function will be realized by alert pins of INA3221 which can notify system when the measured value exceeds the programmed threshold. These alert signals directly control FETs to select the optimum measuring range. Now I uploaded the latest schematics and modified the specifications of Luke. New artwork has been almost completed. I managed to put all components on the board which is the same size as 1st prototype.

Artwork of LukePlus_Rev0_3