BQ76952: Cannot reprogram OTP memory with Settings:Manufacturing:Mfg Status Init[FET_EN] set

Thuc Bui

Part Number: BQ76952
Other Parts Discussed in Thread: BQSTUDIO, , BQ78350

Dear TI team,

I have a problem with reprogram bit Settings:Manufacturing:Mfg Status Init[FET_EN] by BQStudio.

When I change value of Settings:Manufacturing:Mfg Status Init[FET_EN] and check if OTP program possible by click button "Check OTP Programming Possible", I always get an error

like "Device returned Failed: Could not program OTP data. No XOR bits left. This first address of failure was 0x0800."

I found that this error only occur when I change this bit, other bits or other registers are both check and reprogram OK.

Additional, I have reprogramed this bit, Settings:Manufacturing:Mfg Status Init[FET_EN], successfully several times before I get this error.

Please check atteched image

Thank you.

over 4 years ago

0 Matt Sunna over 4 years ago

TI__Guru* 81034 points

Hi Thuc,

The OTP has limits on how many times it can be programmed. The FET_EN bit can be programmed to '1'. Later it can be programmed back to '0'. After that, it cannot be programmed to '1' again. I think this is what the error you see is indicating.

Regards,

Matt

0 Thuc Bui over 4 years ago in reply to Matt Sunna

Prodigy 20 points

Hi Matt,

Thank you very much for your respond.

In this case, I find there is a big problem in both development and MP.

Is there any bit config of BQ76952 has the same behavior with FET_EN bit in OTP programming?

Thanks

0 Thuc Bui over 4 years ago in reply to Thuc Bui

Prodigy 20 points

I checked in bq76952's manual, I found that

As my understanding, one bit cannot reprogram from bit 1 to 0, and maximum reprogramming times for OTP is 8 times. Is that correct?

This is a big issue for for standalone operation. Why have such a restriction like that.

Is there any change for that in next time?

Thanks,

0 Tien Truong DUc over 4 years ago in reply to Thuc Bui

Intellectual 615 points

Andy Liu (BMS), Gautam Iyer

Do you have any experiences for this issue? Please help!

Thank you!

+1 Matt Sunna over 4 years ago in reply to Thuc Bui

TI__Guru* 81034 points

Hi Thuc,

Some gauging devices like the BQ78350 have data flash and can be programmed many times. The BQ76952 does not have data flash, but only RAM and OTP. There is no plan to add data flash to this device in the future - it would require a different semiconductor process.

Best regards,

Matt

0 Thuc Bui over 4 years ago in reply to Matt Sunna

Prodigy 20 points

Hi Matt,

I understood this situation.

Thank you.

Power management

Power management forum

BQ76952: Cannot reprogram OTP memory with Settings:Manufacturing:Mfg Status Init[FET_EN] set