bq34z100 VEN pin connection

Keith Keller

Other Parts Discussed in Thread: BQ34Z100, BQ34Z100-G1

Hello,

If designing with the bq34z100 for only a 1s application, what should be done with the VEN pin?
Should it be tied high / low / floating?

Can you share how large this impedance is? Can I leave this pin unconnected if I’m not using an external voltage divider and not worry about it floating to 2.5V (for example during an EMI event), or should I tie it to VSS, and if so, how strong does my pull-down need to be?

Thank you, Keith

over 11 years ago

0 ThomasCosby over 11 years ago

TI__Guru 73830 points

Keith,

The pin has a current sink to detect the LED push button. You could leave the pin open, if unused.

Tom

0 Nathaniel Wilson over 11 years ago in reply to ThomasCosby

TI__Intellectual 1990 points

Hi,

I had read elsewhere on the forum that the VEN pin can be configured as either an input or an output (which is reinforced by the fact that in the pin table it is labeled as an output but elsewhere in the datasheet it says that it can sense the presence of 2.5V). How is this pin configured as an input or an output?

Also, when configured as an output, what is the voltage of the VEN pin? Would it just be the IC supply voltage?

Thanks for your help!

0 ThomasCosby over 11 years ago in reply to Nathaniel Wilson

TI__Guru 73830 points

Nathaniel,

The VEN pin is configured as as output and input all of the time. It will pulse to 2.5V every 1 second when the voltage measurements are taken. It also sinks current when pulled to 2.5V externally. The current will command the device to temporarily turn the LEDs on.

Regards

Tom

0 giuliano barbieri1 over 10 years ago in reply to ThomasCosby

Prodigy 130 points

Hi,
Does the function of VEN pin (led) work during sleep and full sleep status ?

thanks
Giuliano

0 ThomasCosby over 10 years ago in reply to giuliano barbieri1

TI__Guru 73830 points

Yes, the LED function is supported in all of the sleep modes.

0 Orville Earl over 8 years ago in reply to ThomasCosby

Prodigy 10 points

Hi,

I would like to use the Ven pin to turn on and off my voltage divider. I don't plan to use the LED feature. The (bq34z100-G1) datasheet table 6 has a comment implying that Ven needs to be connected to an "External pull-up resistor connected to VCC" but none of the example circuit connect Ven to an external pull up. Is an external pull-up necessary?

Thanks,
Orville

0 TEC over 8 years ago in reply to Orville Earl

Expert 2475 points

The VEN pin does not require a pull-up resistor. The name should not have been included in the list in the table.

Power management

Power management forum

bq34z100 VEN pin connection