Does Impedance track automatically enable the FETs?

The IT Enable (21) command is used to enable Impedance Track and allow the firmware to control the FETs. There is no reason to issue a Reset (41) command afterwards. The only instance where we have included the reset command in the process is at the beginning for an optimization cycle where you are discharging from battery that is not full. The reset will prevent Ra table updates from occurring during that discharge.

I'm seeing issues where the FETs are not turning on after Impedance track is enabled, but will turn on if the FET enable command is sent or if the reset command is sent. What would cause that?

The IT Enable command should enable the FETs on the bq20z device, unless a protection fault is present. There is a separate FET Enable (22) command on the bq30z and bq40z devices. It must be sent to enable the FETs and allow IT to control them. These devices also have separate enable commands for Lifetime data, Permanent faults, Blackbox recorder, Fuse, etc.

You may see the FETs turn on after issuing a reset , if a protection fault is present and the reset happens to clear the fault.

I've checked the fuel gauge while the FETs were off, and there is no fault. Could a fault flag clear without hitting the recovery threshold that would turn the FETs back on?

I have GGs. How do I attach?

Hello Deckerg,

Please see the link below:

Attaching a file: e2e.ti.com/.../148.4-5-attaching-a-file

Regards,

Sem Amesawu