INA226: Output current reporting issue

Hello Oliver,

Thanks for considering to use Texas Instruments. This behavior seems odd unless your are resetting the device. There are two ways I know of that could reset the device. One way would be to setting bit 15 of the configuration register to 1. The other would be the supply slipping below the power-on threshold of 2V. In both instances, the calibration register clears and you can subsequently only make shunt voltage and bus voltage measurements as these do not require any sort of processing or scaling. I suspect that a transient might be affecting your supply and making it occasionally droop below 2V. Would it be possible for you to set up a oscilloscope probe on your supply to see if this happens? If this does occur, you may need to add a cap or zener to hold your voltage up. Or you might need to trigger your mcu to reprogram the calibration register. If the oscilloscope never triggers, then there might be something with what you are writing. I would check any code corresponding to a write to the configuration register. If you cannot find any issues with the code, I would recommend probing the data lines to see if they are clean, or if there is any signal coupling in and corrupting it.