BQ40Z80: Cannot turn on CHG

Iris Weng

Part Number: BQ40Z80

Hi,

I am testing my circuit about bq40z80.

I tried to turn on the CHG mos by CHG_FET_toogle， and Vgs of CHG fet doesn't change, but samely, when using EVM of BQ40z80,I can see Vgs of CHG becomes 10V.

Could I know why?'

Thank you !!

over 6 years ago

0 Batt over 6 years ago

TI__Mastermind 42535 points

Hi Iris,

Please send the FET_EN command from the command panel. That should turn on the FETs.

0 Batt over 6 years ago in reply to Batt

TI__Mastermind 42535 points

Also, please GND the fuse pin.

0 Iris Weng over 6 years ago in reply to Batt

TI__Prodigy 100 points

Hi Batt,

Thany u.

I have tried to use FET_EN, it also didn't work.

The phenomenon is When I send FET_EN, the bit XCHG of OperationStatusA will change from high to low, but the bit CHG keep being low.

Same thing with DSG.

But the cell voltages are all normal.

And I have left the lab, tomorrow I will try to connect fuse to gnd.

Could I know, besides Fuse, are there some other possibilities， and what else directions can I try？

(I want to test whether the problem is about hardware

I'm trying to hope it's not a hardware problem, because pcb cann't be changed.

Thank you very much.

Regards,

Iris

0 Batt over 6 years ago in reply to Iris Weng

TI__Mastermind 42535 points

Fuse is the only thing that can toggle FETs off, if your protections and PFs are all clear.

0 Iris Weng over 6 years ago in reply to Batt

TI__Prodigy 100 points

It works after connected fuse to GND.

Thanks!

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BQ40Z80: Cannot turn on CHG