BQ78350-R1 DSG and CHG lines closed (XDSG, XCHG are on) all the time

Ran Aloni

Other Parts Discussed in Thread: BQ76940EVM, BQ78350-R1, BQ76940

Hi all,

I have connected the BQ76940EVM to a battery pack.

my XDSG and XCHG flags a permanently on.

I programmed the default firmware of BQ78350-R1, and defined all "Data Memory" parameters.
I send FET_EN command (while in unseal) and I can see the flag is set.

I cannot see any fault or protection flag, "toggle DSG/CHG/PCHG" is not responding in unseal full access mode.

I connected only the BQ76940 to I2C and cleared all faults from GUI.

I re- programmed to default, and imported GG.CSV file and it did not help.

I cleared PF events, did not help.

CHG FET GATE is 17V, DSG FET GATE is ~0V regardless ov Keyin.

any help will be appreciated,
thanks, Ran

over 9 years ago

0 Ran Aloni over 9 years ago

Expert 2386 points

0 ThomasCosby over 9 years ago in reply to Ran Aloni

TI__Guru 73830 points

Ran

The [PRES] flag is not set, so the CHG and DSG FETs will be disabled. Is the shunt installed on the PRES jumper on the EVM? If so, verify that the PRES pin is low on the bq78350-R1 device.

Tom

0 Ran Aloni over 9 years ago in reply to ThomasCosby

Expert 2386 points

Hi Tom,
easier than I thought :-)
where would be the place to set PRES in the "data memory"?
I can only see a reference to the "Enable removal recovery A/B".

thanks,

0 ThomasCosby over 9 years ago in reply to Ran Aloni

TI__Guru 73830 points

This device does not have a bit in DF to ignore the PRES pin. You will have to connect the PRES pin to VSS to enable the FETs.

Power management

Power management forum

BQ78350-R1 DSG and CHG lines closed (XDSG, XCHG are on) all the time