BQ4050: Configuration - 2 Series Cells

Aaron Liebold

Part Number: BQ4050

Hello,

I am trying to get all of the settings in the BQ4050 hammered out for proper operation. Is there a guide that explains what settings are imperative for operation?

My current issue is a persistent cell under-voltage alarm (CUV). I have 2 cells (configured in DA Config), both are above the CUV Recovery voltage, and CUV_RECOV_CHG is not set, but the CUV alarm will not disable. I have also tried switching the CUV_RECOV_CHG bit and applying the charger to no avail.

Do you have any suggestions and is there a document with a setup procedure that I have missed?

Thank you,
Aaron

over 6 years ago

0 Aaron Liebold over 6 years ago

Intellectual 380 points

Here is my schematic:

0 Batt over 6 years ago in reply to Aaron Liebold

TI__Mastermind 42535 points

The only ref docs are the DS and TRM. For clearing CUV, try sending a reset. I can't read the schematic as uploaded.

0 Aaron Liebold over 6 years ago in reply to Aaron Liebold

Intellectual 380 points

Currently, I am attempting to use the DSG_TEST and CHG_TEST options with FET_EN=0 to manipulate the fets. I am seeing no change in the DSG and CHG FET driver outputs and the DSG and CHG bits in OpertationStatus are remaining unset (0). What could be causing this? FET Options = 0x01

0 Aaron Liebold over 6 years ago in reply to Aaron Liebold

Intellectual 380 points

Schematic PDFbatteryPack.pdf

0 Batt over 6 years ago in reply to Aaron Liebold

TI__Mastermind 42535 points

I will respond here within 2 weeks.

0 Batt over 6 years ago in reply to Batt

TI__Mastermind 42535 points

I suspect that your calibration is off. If your voltage gain has been accidentally overwritten, it may read a bad value and therefore set off your CUV. You can check that in your gg file in the calibration section.

0 Aaron Liebold over 6 years ago in reply to Batt

Intellectual 380 points

Thank you for looking into this. It turned out that the BQ4050 believed that the FUSE had been tripped because the FUSE pin was high. I checked all of the settings that I could find to disable permanent faults, the fuse function, and the bit that sets the monitoring of the fuse pin. None of this corrected this issue. The issue was resolved when I connected the FUSE pin to GND (it was floating). Maybe I missed a setting somewhere or this is a firmware issue.

0 Batt over 6 years ago in reply to Aaron Liebold

TI__Mastermind 42535 points

No, fuse pin needs to be pulled low by the protector. It only toggles high if the protector trips. Maybe it is the protector that has failed in this case.

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BQ4050: Configuration - 2 Series Cells