BQ40Z50-R1: Gas Gauging State Update Condition

These values should be updated during a discharge cycle.   How long did your discharge cycle last? 

Andy

Hi Andy,

I was thinking the same. Discharge from SOC 100% down to TermVoltage 6000mV

roundabout 14h (2828mAh).

Hans

Hi Hans,

Could you provide a bqStudio log file and also the gg files before and after the discharge cycle?  

Andy

Hi Andy,

cycle was started. In the end you will get the files as PM.

Thank you.

Hans

Okay. Let me know once the files are ready.

Hi Andy,

the requested files are ready, pls accept my friendship request.

Best Regards

Hans

Hi Andy,

some news about the files?

I took a new measurement with another sample and noticed no update after CC discharge 750mA.

Seconde cycle CC discharge 2000mA, I get an update...  Any depending at current level?

(Values read after REST flag high)

Best Regards

Hans

Hello Hans,

You have to be in discharge mode, above discharge current threshold for more than 500 seconds.

Hi Kang,

Dsg Current Threshold is 100mA, Design Capacity 2765mAh.

Discharge from full to empty about 14h at CC 200mA load current.

Would you like to check the srec?

Regards

Hans

Hi Hans,

Yes. Can I also have your srec file?  I plan to run some simulations to see if I can find the root cause. Thanks.

Andy

Hi Andy,

are there any news about the simulation?

Regards

Hans

Hi Hans,

I was quite busy last week and didn't have a chance to run the simulation.  I will check the srec file you sent to me and start to run the simulation if your srec and log files are both good.

Andy

Hi Hans,

What' are the unseal key and full access key?

Andy

Hi Andy,

you will receive the keys as PM.

Hans

Hi Hans,

I have started a simulation job on our server, which should take a few hours.  I will provide some updates once I get some good results. 

Andy

Hi Andy,

this project becomes uguent. Couldn't you recorded new findings?

Hans

Hi Hans,

I was out of office for a few days last week and therefore didn't have a chance to look into this issue.

Let me check the simulation results and then provide my feedback shortly. 

Andy

Hi Andy

time goes by .... what are the next steps?

Hans

Hi Hans,

Here are the Avg I Last Run and Max Avg I Last Run settins I see in the srec file you shared with me.  They are the initial settings for my simulations. 

"Gas Gauging","State","Avg I Last Run","-1502","mA"

"Gas Gauging","State","Max Avg I Last Run","-2968","mA"

I ran the simulations using the log file you provided. The plot below shows the current and voltage curves. The discharge current is -200mA.  

After the simulations are over,  I see can the two values above are the still same.

It seems like that I am able to duplicate the same issue as you mentioned, though I don't know the root cause yet.

I would need to check with our firmware team to figure out the root cause.  I will give you some updates next week.

Andy

Hi Andy,

thank you for your feedback.

Hans

Hi Andy,

any news from your firmware team?

I have a customer meeting on thursday and therefore it would be an advantage to say something about the issue.

If we have the choice to switch to BQ40z50-R2, do you think that's a better idea? I've worked in serveral projects with

revision 2 and never seen this issue.

Hans

Hi Andy,

If there any news from FW-team?

I'm working on the Version with -R3 in parallel.

Hans