BQ2012: BQ2012

liqiang zeng

Part Number: BQ2012
Other Parts Discussed in Thread: BQ40Z50, BQ27541

Dear friends

I need help. I am using bq2012 in my project (6 NIMH cells in serial). The defect rate is up to 5% in mass production. All the defect are related to BQ2012. BQ2012 damaged so easily.

Some symptom :

1) High quiescent current. Normally, the quiescent current is around 0.12mA. but some show 1.6mA.

2) Incorrect initial LCM data. It doesn’t resume to correct initial LCM after reset. Even cut off the power and connect again. No correct initial LCM value appear.

3) BQ2012 have no function. I measured the quiescent lower than normal , it is only 0.018mA ( normally, it 0.12mA).

4) Normally, the charge pin should be low when the battery is not fully charged. But low state never appear even fully discharged.

Schematic for reference. The bq2012 is powered by 3.3V regulator.

Thanks

zeng

70-0424 Sheet2.pdf

over 5 years ago

0 Onyx Ahiakwo over 5 years ago

TI__Guru* 76230 points

hi Zeng

Your symptoms seems to be related to ESD damage. Is your production environment esd free? Can you submit the device for a FA via your local TI contact? The device is really old, NRND and support for it is limited. You should be using a more recent device.

thanks
Onyx

0 liqiang zeng over 5 years ago in reply to Onyx Ahiakwo

Prodigy 180 points

Hi Onyx

Thanks for your reply, I also guess ESD damaged. But our environment is ESD free. Never this issue on our other product with BQ40Z50 , bq27541 and other Ti devices. As per the schematic, No ESD protection diode for the DQ PIN. Do you think any ESD protection is necessary for other pin, such as charge control pin and other unused pin.

Thanks

zeng

2402.70-0424 Sheet2.pdfer PIN , such as charge control pin and other unused pin.

0 Onyx Ahiakwo over 5 years ago in reply to liqiang zeng

TI__Guru* 76230 points

Hi Zeng
If those pins are routed to a conector then there needs to be esd protection

thanks
Onyx

0 liqiang zeng over 5 years ago in reply to Onyx Ahiakwo

Prodigy 180 points

Hi Onyx

Thanks for your help.

I have one more question need help.

When I try to soft reset BQ2012 by EV2300, I input 39 and 00. But can not successfully reset the register. I would like to know what may result in reset fail.

Best regards

ZENG

0 Onyx Ahiakwo over 5 years ago in reply to liqiang zeng

TI__Guru* 76230 points

Hi Zeng,
The DS says "By writing the RST register contents from 00h to 80h, a bq2012 reset is performed"

thanks
Onyx

Power management

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BQ2012: BQ2012