BQ40Z50: bq40z50 - start charging

Daniel Lenz1

Part Number: BQ40Z50
Other Parts Discussed in Thread: EV2400, BQSTUDIO,

Hi community,

i use the bq40z50evm with the bq24171evm and the EV2400 for communication.
Furthermore i use the bqStudio. I also updated the firmware to bq40z50-R3.

At first i updated the cell chemistry from the database.

My Problem is that i can not charge my battery pack.
The battery mode is in discharge / relax mode (read only).

Can you help me please?

over 5 years ago

0 Steven Yao over 5 years ago

TI__Genius 12215 points

Hi, Daniel

First, you need to enable the fet by send fet enable command, send 0x0022 to 00. You also need to pay attention to the NR bit in DA configuration in data flash, if the syspres pin of bq40z50 is unconnected in your system in normal operation, they to enable fet, you need to set this NR bit to 1, otherwise, if this pin is connected to GND during normal operation in your system, then NR bit would not affect the status of the FETs

0 Daniel Lenz1 over 5 years ago in reply to Steven Yao

Prodigy 40 points

Hi Steven,

thanks for your answer.
The SYS_PRES Pin ist shorted to GND. So I don't need to set the NR bit in the DA Register.
Via Battery Management Studio I send the UNSEAL command and than I send FET_EN.
Charging don't starts.

The "Relative State of Charge" is set to 100% but my batteries are not full (3V instead of 3.7V).
How can I reset this function?