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BQ27411-G1: SoC always returns 0

Part Number: BQ27411-G1

Originally we were using the BQ27441DRZR-G1A with only I2C commands. We followed the Quickstart guide and ended up with a fairly simple procedure:

1. Unseal

2. Enter config update mode

3. Write the design capacity, design energy, terminate voltage, and taper rate

4. Handle the checksum

5. Exit config update mode

6. Seal

Then we would read the SoC on a regular interval. It worked great without any issues!

However, we now switched to the BQ27411DRZR-G1A and the same procedure doesn't seem to work. When we try and read the SoC it always returns 0. It can read the temperature and voltage without any issues, but not the SoC. As far as I can tell, the main differences between these parts is that the GPOUT pin changed to the PROG pin (so we ensured that the PROG pin is pulled down per the datasheet recommendation) and the BIN pin changed to the TEST pin (again, we ensured that this was pulled down per the datasheet recommendation).

Do you need to send some sort of extra commands to get the BQ27411DRZR-G1A to give a valid SoC? I don't see any Quickstart guide for what I2C commands need to get sent to set up and use the BQ27411DRZR-G1A.

Thanks,

David