BQ27220: I2C FW update issue with BQ27220

Feng bin Su

Part Number: BQ27220
Other Parts Discussed in Thread: BQSTUDIO, EV2400

Hi team,

My customer has used the EVM to flash the I2C and they faced some flash issue with bqstudio. Please refer the below figure for the failure.

Is there any reason to induce it?

Customer also mention that they has boot code issue in the factory which is similar issue as the below link.

I am asking the waveform of I2C and also the trace of I2C of pass and fail log from customer. Would you also need anything else to analyze it?

over 4 years ago

0 Wyatt Keller over 4 years ago

TI__Guru** 105770 points

Hello Feng,

Are they using bqStudio or the bqUpdater?

If they are running into similar issues to the linked post I would follow all the suggestions there for unsealing/timing requirements.

Is this a gm.fs writing issue or unseal issue?

Sincerely,

Wyatt Keller

0 Feng bin Su over 4 years ago in reply to Wyatt Keller

TI__Expert 8790 points

Hi Keller,

It is at customer board.

Please refer the below figure for I2C timing waveform. The operation frequency is 100khz.

The setup time and hold is in the spec. Would you think the rising or the failing time will induce this update FW issue?

Setup time 180ns > 0

Hold time 5.62us > 250ns

0 Wyatt Keller over 4 years ago in reply to Feng bin Su

TI__Guru** 105770 points

Hello Feng,

Is this using bqStudio or bqUpdater?

I don't think it's a rise/fall time issue, the time constant doesn't look very long for the waveforms. Are they able to update the default firmware?

Sincerely,

Wyatt Keller

0 Feng bin Su over 4 years ago in reply to Wyatt Keller

TI__Expert 8790 points

Hi Keller,

We are setting the register by I2C host directly. Please refer the below I2C log of pass and fail log which is captured by Saleae.

It seems that I2C slave has latch the data to induce the failure. May I have your help about it? Thanks.

I2C.zip

0 Wyatt Keller over 4 years ago in reply to Feng bin Su

TI__Guru** 105770 points

Hello Feng,

The -NG file is the failure file and the other is successful?

The address of the gauge for a read is being sent too close in repetition, I think the bus is being overloaded or the timing is being violated especially for recovery.

Sincerely,

Wyatt Keller

0 Feng bin Su over 4 years ago in reply to Wyatt Keller

TI__Expert 8790 points

Hi Keller,

We have adjust timing with 1s for each comment but it still happens. Please refer the attached. Let me know your comments about it .Thanks.

0 Wyatt Keller over 4 years ago in reply to Feng bin Su

TI__Guru** 105770 points

Hello Feng,

Can you compare these with our toolchain captures? You should be able to see any discrepancies with the waveforms to resolve the issue.

Sincerely,

Wyatt Keller

0 Feng bin Su over 4 years ago in reply to Wyatt Keller

TI__Expert 8790 points

Hi Keller,

Customer's project has massed production already. The fail rate is not very high. If the failure is happened at the board it only can be fixed when the battery discharge into no power and POR.

The fail rate is about 0.0038%
Customer's SW help to release the FW with the I2C De-Initial when happen I2C error on Fuel gauge communication, but using bqStudio by TI’s EV2400 is still NAK,

From the I2C log, it seems SDA has been locked at stop stage and it induce the NAK at failure case.

May I know whether the another similar case has been fixed or not? It seems the two behavior is very similar.

Thank for your kindly help.

https://e2e.ti.com/support/power-management/f/power-management-forum/904563/bq27220-no-unseal-response

0 Wyatt Keller over 4 years ago in reply to Feng bin Su

TI__Guru** 105770 points

Hello Feng,

I don't believe a solution was found to this issue yet. I would follow the same recommendation as the other post and perform a POR to reset the gauge to leave the error state.

Sincerely,

Wyatt Keller

Power management

Power management forum

BQ27220: I2C FW update issue with BQ27220