BQ27426: Inquiry about setting and overall function

Michael Jeong1

Expert 2630 points

Part Number: BQ27426
Other Parts Discussed in Thread: GPCCHEM, BQSTUDIO,

Hi,

I have some questions.

I want to get your kind reply about my inquiry.

* Our customer's configuration for fuel gauge.

We use default except below items.

ChemID: 0x1202

Design capacity: 80mAh

Design energy: 296mWh

Terminate voltage: 3400mV

Taper rate: 384

Sleep current: 1mAh

Q invalid MaxV: 3800mV

Q invalid MinV: 3700mV

V at chg term: 4200mV

Taper voltage: 4100mV

* Symptoms.

1. When reach a point between the 2-8% it suddenly jumps to 99% SoC and stays there.

2. some times, SoC is jumping.

3. When charging, SoC changed from 92% to 2%.

* Below is my questions.

1. How do I have to set which items of Data Memory to clear above symptoms?

2. When I testing Learning Cycle, error has occurred.

error message is inserting charger. at that time, during charging.

3. Could you send example file for setting Data Memory?

4. Could you explain and setting guide for Ra Tables?

5. How do I calibration?

Best regards,

Michael

over 5 years ago

0 Andy Liu (BMS) over 5 years ago

TI__Guru 52115 points

Have you ever used the GPCCHEM tool to check if the chemistry id is proper? If so, share the GPC report with us.

Also, please dump a gg file with bqStudio and share it with us.

Regarding the SOC jump issue, can you provide a bqStudio log file?

Andy

0 Michael Jeong1 over 5 years ago in reply to Andy Liu (BMS)

Expert 2630 points

Hi Andy,

First of all, I want to get your kind explain about my questions each.

Because I need to understand setting of this device.

I'm looking forward to receiving good reply and review from you.

* I have another question.

-. What's the setting value of "Qmax Cell 0" ?

Is it equal to Design Capacity?

Here is what you requested.

I don't have a gg file.

bq27426 - Charging.txt

bq27426 - Discharging.txt

Best regards,

Michael

0 Andy Liu (BMS) over 5 years ago in reply to Michael Jeong1

TI__Guru 52115 points

To solve your issues, I need you to provide bqStudio log files. I cannot use the log files you uploaded to find the root cause.

Also, please provide your gg file. I will review it to check whether your configurations are okay.

Set the Qmax Cell 0 to be the same as the Design Capacity. You don't need to change Ra table by yourself because it is updated by the gauge itself.

Regarding calibration, use the Calibration tab in the bqStudio. See the steps below.

Voltage Calibration

1. Measure the voltage across Pack+ and Pack–.

2. Type the voltage value in mV into Enter measured value.

3. Press the Calibrate button.

Board Offset Calibration

It is expected that no current is flowing through the sense resistor while performing this calibration step.

1. Remove load and short PACK– to LOAD–.

2. Press the Calibrate button.

Andy

0 Michael Jeong1 over 5 years ago in reply to Andy Liu (BMS)

Expert 2630 points

Hi Andy,

Thanks for your kind explain and reply.

Our customer has a summer vacation now.

So, I didn't have a gg file and logo file.

I have some question about configuration.

If you give me some guide, I'd like to test again.

At initial configuration, I used default setting except as I mentioned above.

I will set Qmax Cell 0 = 80mA, please give me what do I need to set at another configuration.

Best regards,

Michael

0 Michael Jeong1 over 5 years ago in reply to Michael Jeong1

Expert 2630 points

Hi Andy,

Our customer's battery capacity was changed from 80mA to 90mA.

Here is data sheet & test report.

Could you please review this battery whether it is applicable to bq27426 or not?

I have another question.

How do I set below items.

-. Q invalid MaxV: ??mV

-. Q invalid MinV: ??mV

이어버드 LE807-471224-90mAh+PCM+Wire（防水+双面胶）Battery specification A1 2018-04-13.pdf

Test report of 471224_Highpower_180605.pdf

Best regards,

Michael

0 Andy Liu (BMS) over 5 years ago in reply to Michael Jeong1

TI__Guru 52115 points

Please use the GPCCHEM (https://www.ti.com/tool/GPCCHEM) to check whether the battery can be used with bq27426. Also, this tool can tell you which chemistry id is the best one.

These two paramters you are looking for are updated when a different chemistry id is selected. Don't change them by youself.

Andy

0 Michael Jeong1 over 5 years ago in reply to Andy Liu (BMS)

Expert 2630 points

Hi Andy,

I have a question about GPCCHEM.

I can see like below comment on slva725a document.

An easy recording method utilizes TI's bqStudio software utility called GPC Packager that reads data directly from a TI fuel-gauge.

I can't see GPC Packager in bqStudio tool.

Could I send you .log file in bqStudio tool?

Pls, give me guide.

Best regards,

Michael

0 Andy Liu (BMS) over 5 years ago in reply to Michael Jeong1

TI__Guru 52115 points

The GPC package is NOT available for BQ27426.

Please follow the instruction manual to prepare the log file and submit it to the GPCCHEM tool.

Andy

Power management

Power management forum

BQ27426: Inquiry about setting and overall function