BQ76952: OTP fail

Allen Hui

Prodigy 160 points

Part Number: BQ76952
Other Parts Discussed in Thread: BQSTUDIO,

hi sir，

I have imported the values from a .gg file, and then finishing the programe process to OTP memory.

after re-reading the RAM value, i found some of the values are not correct and some are right.

so I perform the programing process again, and the values in OTP are totally right.

there are two question：

1）after the first programe process, why there are some values are not correct?

2) for this chip can only program in one time, so, in the second programe process, all these values are effected?

thank you very much.

over 2 years ago

0 Andria McIntyre over 2 years ago

TI__Expert 8526 points

Hello Allen,

In response to your questions:

1) Which values did you observe to be incorrect? If you are seeing errors in the calibration section, this is probably because BQStudio does not automatically import these parameters.

Special instructions for changing these values can be found here: (+) BQ76952: Importing from file does not read all values - Power management forum - Power management - TI E2E support forums

2) Although OTP does mean One Time Programmable, the BQ76952 allows 2 writes to a bit for OTP. This means that even if you had failed to program a bit in OTP, you are able to amend that through another write.

Please note, though, that OTP memory is initially all zeros. Each bit can be left as a "0" or written to a "1," but it cannot be written from a "1" back to a "0." More information can be found in section 3.2 of the Technical Reference Manual: BQ76952 Technical Reference Manual (Rev. B) (ti.com) and the Calibration and OTP Programming application note: BQ769x2 Calibration and OTP Programming Guide (Rev. A).

Additionally, you may find this previous thread helpful: (+) BQ76952: OTP Programming - Power management forum - Power management - TI E2E support forums.

Best,

Andria