【GUI Protection setting Problem】BQ 78350

Kevin Li

Intellectual 300 points

Other Parts Discussed in Thread: BQ78350-R1, BQSTUDIO, BQ78350, BQ76940

I want to set COV threshold at 4.25V and delay 4s.

But It didn't work.

I did try two version 1E9B_1_03-bq78350_R1.bqz & 3644.1E9B_1_03-bq78350_R1.bqz .

I want yo control COV delay time of threshold voltage.

How should I do.?

Thank you ~~~

over 9 years ago

0 Kevin Li over 9 years ago

Intellectual 300 points

I want to setting OCV Delay time for 1s.

0 ThomasCosby over 9 years ago in reply to Kevin Li

TI__Guru 73830 points

You should be able set the Delay to 1s. It may be a bqz problem. If you are using bqStudio v1.3.45, then try using this bqz for the bq78350-R1. .

https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/7041.1E9B_5F00_1_5F00_03_2D00_bq78350_5F00_R1.bqz

0 Kevin Li over 9 years ago in reply to ThomasCosby

Intellectual 300 points

I try 7041.1E9B_1_03-bq78350_R1.bqz

but delay times still for 2s

And I have try to set the delay time for 10s

But same results

0 Kevin Li over 9 years ago in reply to Kevin Li

Intellectual 300 points

Did I miss something?

0 ThomasCosby over 9 years ago in reply to Kevin Li

TI__Guru 73830 points

I tested this on the bench and it looks like the delay time for the bq78350 to disable the CHG FET on the bq769xx will be too long to allow the FET to turn off within 1s. I set the Delay to 0s and the FET turned off in 1.2s, so maybe that will be close enough.

0 Kevin Li over 9 years ago in reply to ThomasCosby

Intellectual 300 points

I use 78350+76940

May I know which IC did COV protect ?

I set the Delay to 0s and change the cell voltage three times.

Delay time is not stable.
red=Charge mosfet ; blue=cell voltage

0 ThomasCosby over 9 years ago in reply to Kevin Li

TI__Guru 73830 points

Both devices have a part in the protection control. The bq78350 contains the settings and declares the fault. It tells the bq76940 to turn off the FET. The bq76940 also monitors voltages and currents and reports these values to the bq78350. The response variations are mostly due to measurement timing and communication between the devices.

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【GUI Protection setting Problem】BQ 78350