I'm attempting to calibrate and use the internal temperature sensor on the bq20z45-R1 gas gauge. I'm going through the calibration process in bqEasy and I reach the point when I'm prompted to switch over to the "Calibrate" tab to do Temperature Calibration.
The temperature reading varies between 232.9 C and 233.4 C without any calibration. This temperature reading seems very incorrect to me. The chip itself is not noticeably warm and the board is in room temperature.
Two issues:
1. I cannot input an actual temperature greater than 12 deg C difference from the measured temperature without getting an error.
2. If I make up an "actual temperature", the Measured temperature jumps to 19.8 C and then back to an absurdly high value. That measure temperature of 19.8 C is probably much closer to the actual chip temperature than 233 C.
What's going on here and how can I get the internal temperature sensor to work?
I'm observing this same problem on two different custom boards. There are currently no external temperature sensors and the TOUT, TS1, and TS2 pins have been left floating.
Thanks!