BQ3050: Entering Options Shutdown Mode

Sabrina Boeser

Part Number: BQ3050

Hi,

in one of our already released products we observed the battery pack entering Shutdown Mode without meeting all conditions defined.

We have set [SHUTV] = 1.

Regarding bq3050 Tech Ref it means Shutdown Mode is entered when Min (CellVoltage4..1) <= Cell Shutdown Voltage AND Current <=0 for a period of Shutdown Time
AND Pack Voltage < AFE Shutdown Voltage threshold.

Could it be that the last AND should be OR ? That the pack enters shutdown mode with one cell voltage <= cell shutdown Voltage even though Pack Voltage is still higher than AFE Shutdown Voltage?

Or is there any other path entering Shutdown Mode?

We observed packs entering shutdown mode even though pack voltage was far above AFE Shutdown Voltage.

Thanks,

Sabrina

over 5 years ago

0 Sabrina Boeser over 5 years ago

Prodigy 150 points

Also , it is correct that there is a Max Error jump to 100% when entering Shutdown Mode?

Thanks, Sabrina

0 Wyatt Keller over 5 years ago

TI__Guru** 105590 points

Hello Sabrina,

I will check with the firmware team and let you know what they say.

Sincerely,

Wyatt Keller

0 Wyatt Keller over 5 years ago

TI__Guru** 105590 points

Hello Sabrina,

The firmware team verified that the TRM is probably correct. The pack voltage is not the battery stack voltage, when the FETs are off the pack voltage will drop. The pack voltage < AFE shutdown threshold parameter is basically to check if there's a charger present while the cells are below the threshold so it can recharge them without going into shutdown.

Sincerely,

Wyatt Keller

Power management

Power management forum

BQ3050: Entering Options Shutdown Mode