BQ27742-G1: BQ27742 - Avg I Last Run

Hello Peter,

Can you send me a log file of this happening? I am suspecting the voltage drops below the Flash Update Ok Voltage parameter in data memory (2800mV) which could be why Avg I last Run is not updating.

Regards,

Nick Richards

Hi Nick

Hey Peter,

Load mode and load select should be the default values. These settings are most likely not related to the Avg I last Run parameter updating.

Regards,

Nick Richards

Hi Nick,

Can you tell me what condition the " Avg I last Run " would update ?

Thanks!

Regards,

Peter

Hello Peter,

That should update after a discharge, when the battery is in rest.

Regards,

Nick Richards

Hi Nick,

Could you tell me if continuous discharge needs to be > 500 seconds?

I found this information in the TRM. I used a 1A discharge, but no changes occurred.

Attached are the schematic and gg file.

Please help me confirm.

Thanks!

Load Select 2 (0613).log 

Regards,

Peter

Hey Peter,

Try changing load select to 0 and see if that makes the register update. If not, then I believe that this register updates after a complete discharge of the battery. So the battery will need to be discharge close to terminate voltage.

Regards,

Nick Richards

Hi Nick,

The information has been update. Thnak you for your reply.

However, i would like to know the conditions for complete discharge. 

I used 1A discharge, but not near terminate voltage.

Then used 0.6A, < terminate voltage.

Please check with the attachment.

Load Select 6_SOC 50 (0620).logLoad Select 6_SOC 100 (0624).log

Is this normal ?

I need to explain this to my client.

Thanks!

Regards,

Peter

Hi Nick,

Hi Nick,

If the discharge current is not constant until the discharge ends.

Do you think it will update ?

You can refer to the conditons in the picture.

Regards,

Peter

Hi Peter,

As long as there is a discharge current (doesn't matter whether it is constant or not) then it should update. Now, Dsg Current Threshold should be set so it can detect the lowest current. Therefore, Dsg Current Threshold should be set for less than 5mA, and Quit Current Threshold needs to be set for less than Dsg Current Threshold.

Regards,

Nick Richards

Hi Nick,

I will check and confirm. Thank you for your response.

If "Avg I Last Run" is not updating, will it affect anything? For example, SOC calculations or other functions?

Regards,

Peter

Hi Nick,

Hello Peter,

Discharge rate has to be greater than 0.1C for RA table to update. This could also be the reason Avg I last run is not updating.

Regards,

Nick