BQ34Z100-R2: LED button suddenly stopped working

Hi,

Can you share a schematic of the pcb and the .gg file?

Regards,

Evan

Hi again. We have talked before regarding this matter and I DM'd you the schematics because I didn't want to put them public.

However, we have decided to buy an evaluation board to eliminate all variables and compare the behavior with our own design. I got the evaluation board, I set the jumpers accordingly (single cell battery, extenal leds), and I configure the LED register with my EV2400. Everything works well. The LEDs light up when I long press the button. I even updated the firmware to the latest one at the time of writing (2.02.31) and it continues to work like a charm.

But I unplugged the battery and plugged it once again, and this time, I have the same weird behavior. When I set the LED_ON bit, 3 LEDs light up as configured, but when this bit is clear, the button just won't work.

I have even created a golden image when I got it working properly, but restoring this image didn't solve the bug. I've tried reflashing the firmware given by texas instruments, but once again, it didn't solve the problem.

I'm stressing the fact that this happens on the evaluation board.

Maybe it's relevant, but I haven't done anything besides updating the firmware and configuring the LEDs. I haven't even chosen a chemistry because we are still trying to figure out which one matches the closest with our battery.

Do you think this could be a problem with the firmware?

Hi,

Can you share your .srec used on the EVM, I am going to try to recreate the issue on my end.

Thanks,

Evan

Sure.

This is the official .srec that I flashed and then set the LED register to 0x23:

https://drive.google.com/file/d/1uR2F1it5J4D_3axTa4eAlXFZJY1gqIp0/view?usp=sharing

And this one is the golden image that I've taken after I modified the register:

https://drive.google.com/file/d/1TgjGKDU8OnOaDKn4nje3sFegsP-s2eiT/view?usp=sharing

Hi Alex,

When I uploaded the .srec you sent, the gauge did not work correctly at first. I then restored a default .srec and the gauge functioned as expected, I then reuploaded your .srec and the LEDS did not turn on. 

I am unsure what is wrong with the file you sent but I recommend taking the .gg file off the .srec you configured and try to upload it to a default .srec or reconfigure a default .srec and see if this fixes your issue.

Thanks,

Evan

Hi,

Thanks for testing it for me. When you said "I uploaded the .srec you sent, the gauge did not work correctly at first", I'm guessing you uploaded the golden image that I sent you in the second link, right?

And then when you restored a default .srec, what file did you use? My first link contains the .srec that I got from texas instrument's website, so it's the most up to date firmware for this battery gauge. Did you use this file or another? Because I tried restoring the gauge with this file and reconfigured the LED register, but it didn't seem to restore the functionality with the button. If you used another default .srec than the one I gave you, can you please share it with me?

And just to check that my procedure is correct, when you restore a new .srec you just give it the file path in the Programming tab in BqStudio and click on program, right? And configuring the LEDs is just a matter of changing the value of the LED register an clicking on write.

Thanks for your patience once again.

Hi,

Please allow me sometime to look into this.

Thanks,

Evan

Ok, now I know how to consistently reproduce the issue.

If I flash bq34z100_G1_v0_16_build_17.srec, everything works correctly, even after I unplug and replug the battery.

If I flash bq34z100_v2_02_build_31.srec, the LEDs work until I unplug the battery. After I replug the battery, the LEDs don't turn on anymore when I press the button. The only way I found that solves the issue is to flash bq34z100_G1_v0_16_build_17.srec. Reflashing bq34z100_v2_02_build_31.srec won't solve the issue.

I'm using bqStudio 1.3.124, and I'm loading the bqz file that corresponds to the version that I flashed, either 0100_0_16-bq34z100G1.bqz or 0100_2_02-bq34z100.bqz. I just copied these files to C:\ti\BatteryManagementStudio\config so bqStudio will automatically use the right bqz file.

For now, I'm going to use the old firmware as this one seems to work for me. I don't know the root cause of this issue, but I will retry the experiment using another computer and see if I have the same problem.

Thank you for your support. I will keep you informed with any updates on this matter.

Hello,

Today's a holiday and no one is in the office. We will get back to you tomorrow.

Regards,

Nick Richards

Hi Alex,

Thanks for the update, please let me know of any new updates. Glad to hear old FW seems to be working, I will investigate more into that.

Regards,

Evan