BQ27546-G1: time to enter hibernate

Ben Genereaux

Intellectual 1040 points

Part Number: BQ27546-G1
Other Parts Discussed in Thread: BQSTUDIO, EV2400

Hi team,

How long should we expect it to take to for the relaxed cell measurement to put the gauge into Hibernate mode?

Following this process using BQStudio with an eval board:

Setting the HIBERNATE bit to 1 and disconnecting the EV2400 from the BQ27546 eval board
- Hibernate current threshold is set to 8 mA
- Let the battery cell sit connected to the BQ27546 eval board with no load for > 4 hours and the measured current remained at 65 uA
- DMM reads 65 uA with a ~ 300 uA draw every 20 seconds

At some point after 4 hours the device goes in to Hibernate mode.

Ben

over 2 years ago

0 Dominik Hartl11 over 2 years ago

TI__Guru 64266 points

This depends on the battery. The gauge requires an OCV measurement and that will only happen when the cell voltage is stable enough. This can take several hours.

0 Ben Genereaux over 2 years ago in reply to Dominik Hartl11

TI__Intellectual 1040 points

Hi Dominik,

What about a scenario where the device exits hibernate mode, then immediately tries to re-enter? Would you expect the cell to be relaxed or could this also take several hours to get the OCV measurement?

Thanks,

Ben

0 Dominik Hartl11 over 2 years ago in reply to Ben Genereaux

TI__Guru 64266 points

The gauge won't enter hibernate mode unless it took an OCV measurement and that won't happen unless the voltage is stable (relaxed).

Power management

Power management forum

BQ27546-G1: time to enter hibernate