BQ20Z655-r1: pack current calibration issue

Hello Sean,

Calibration must be performed with power supplies. Was a charge current applied or a discharge current? Seems like overcharge mode indicates a charge current

I applied a 2A discharge current with the electronic load and entered -2000 into the bqevsw calibration screen, thats when it started measuring large positive values

That would mean that the current is reversed. Please compare the board to EVM schematics and see if SRN/SRP are connected on the correct side.

This is only seems to occur during the pack current calibration process. During charge and discharge, the current measures in the correct polarity.

Hello Sean,

We have never seen that happen. Is there no issue if you don't open calibration screen?

Yes, this issue only seems to occur when I go to calibrate the pack current. As soon as I hit 'calibrate part as indicated below', thats when the current measurements go out of whack.

Hello Sean,

During calibration bqEVSW may report incorrect values on the display, but once calibration is complete it should show the correct value. If you are applying a current across the sense resistor, is it possible that the polarity is reversed? That would be consistent with seeing overcharge condition.