BQ40Z50-R1: Current calibration

john xiao

Intellectual 470 points

Part Number: BQ40Z50-R1
Other Parts Discussed in Thread: BQ40Z50, BQ27542-G1

Dear all:

I use BQ40z50-R1 design 4S Lithium battery protection board.the SCH and GerberfileSCH&Gerberfile.zip

the BQ40z50 dataflash configuration is2.gg.zip

After -2000A current calibration,I found there is always 3ma~5mA current in idle state.the log data is7571.1.zip

What causes small current generate in idle state?why the BQ40z50-R1 not CC Offset calibrate and Board offset calibrate as BQ27542-G1?

over 7 years ago

0 Miguel Angel Rios over 7 years ago

TI__Expert 4640 points

Thanks for your question i have assigned someone to look into this.

0 Swaminathan Ramanathan75031 over 7 years ago in reply to Miguel Angel Rios

TI__Expert 6575 points

Hi John,
The app note at www.ti.com/.../slua734a.pdf has instructions on calibration. There is an error in step 9 of section 2.4.2 in that document to be aware of. The formula should be:
Board offset = (ADCCC × Coulomb Counter Offset Samples) – CC Offset
You can also look at some of the comments in the following post:
e2e.ti.com/.../1766965
Please let me know if you still have calibration issues.
Regards,
Swami

Power management

Power management forum

BQ40Z50-R1: Current calibration