BQ34Z100-R2: Alert signal

Saravanakumar Irulappan

Part Number: BQ34Z100-R2
Other Parts Discussed in Thread: BQSTUDIO

Tool/software:

Hi,

We would like to use an interruption from the fuel gauge to wake up the micro controller (when uC in sleep mode, we need that the fuel gauge wakes up the power supply)?

Can we use the pin 1 (P2) for Interrupt?. If yes, then please let us know about the compatible voltage level. So that we can pull-up the P2 pin accordingly and whenever alert occurs then this pin will go low and interrupt the microcontroller.

Please check and confirm.

Regards,

Saravana

4 months ago

0 Alan Frias 4 months ago

TI__Mastermind 27195 points

Hello Saravana,

Yes you should be able the pin to wake up the micro controller on the alert signal that can be configured within BQStudio, in terms of compatible voltage level it works with 2V logic level and you can see this within the EVM as it drives an LED driver with it.

Thank you,
Alan

0 Saravanakumar Irulappan 4 months ago in reply to Alan Frias

Prodigy 190 points

Hi Alan,

Is it a open drain output pin? Can we pull-it up to 3.3V? We are not using LED. So it is MODE 0 as per table 3-10.

Please confirm.

Regards,

Saravana

0 Alan Frias 4 months ago in reply to Saravanakumar Irulappan

TI__Mastermind 27195 points

Hello Saravana,

If you are using MODE 0 than no signal would be sent out meaning that it wouldn't alert the MCU if a event occurred, thus MODE 1 might be the better mode for the reason given.

Saravanakumar Irulappan said:
Can we pull-it up to 3.3

I would need to reach out and see what is the acceptable voltage range for this device.

Thank you,
Alan

0 Saravanakumar Irulappan 4 months ago in reply to Alan Frias

Prodigy 190 points

Hi Alan,

Sure. I am waiting for your input on voltage level for pull-up.

Regards,

Saravana

0 Alan Frias 4 months ago in reply to Saravanakumar Irulappan

TI__Mastermind 27195 points

Hello Saravanakumar,

It seems like 3.3V volts would pass the maximum input range for this pin with it being at most 3.05V.

Thank you,
Alan

Section 6 of the datasheet:

0 Saravanakumar Irulappan 4 months ago in reply to Alan Frias

Prodigy 190 points

Thanks Alan,

So, if I pull the pin P2 to 2.5V, then it should be fine right?

If I leave it open, then what will be voltage level at P2?

Regards,

Saravana

0 Saravanakumar Irulappan 4 months ago in reply to Saravanakumar Irulappan

Prodigy 190 points

Can I use REG25 supply for the pull-up at P2 pin using 10K resistor?

+1 Alan Frias 4 months ago in reply to Saravanakumar Irulappan

TI__Mastermind 27195 points

Hello Saravanakumar,

Saravanakumar Irulappan said:
Can I use REG25 supply for the pull-up at P2 pin using 10K resistor?

-It is not recommend to have REG25 to power multiple paths, but it should be workable but it would need testing on the user end to validate this

Saravanakumar Irulappan said:
So, if I pull the pin P2 to 2.5V, then it should be fine right?

Yes it does not pass the voltage threshold for the pin.

Thank you,
Alan

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BQ34Z100-R2: Alert signal