BQ27425-G2A: BIN pin connection on when Battery Detection is not necessary

Gonzalo Sanchez1

Part Number: BQ27425-G2A

We are planning to use the BQ27425-G2A in a design that has a non-removable battery pack without a pull-down resistor and we are not sure how we should connect the BIN pin.

I've found two posts about this, in one of them, it is recommended to tie the BIN pin to Vss whereas in the other it is recommended to tie the BIN pin to Vcc with a weak pull-up resistor.

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/285670/bq27425-g2a-using-with-pulled-down-bin-pin-to-gnd-always

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/586263/bq27425-g2a-recommended-bin-pin-connection-in-case-of-battery-detection-is-not-necessary

Which would be the right way to connect BIN?

Best regards

Gonzalo.

over 3 years ago

0 Wyatt Keller over 3 years ago

TI__Guru** 105590 points

Hello Gonzalo,

I've assigned someone to take a look at your question within the next 24 hours.

Sincerely,

Wyatt Keller

0 Gonzalo Sanchez1 over 3 years ago in reply to Wyatt Keller

Prodigy 70 points

Hello Wyatt, may I know if there is any news about this?

Best regards,

Gonzalo.

+1 Dominik Hartl11 over 3 years ago in reply to Gonzalo Sanchez1

TI__Guru 60846 points

Both methods from the previous E2E posts work.

If you connect it to GND, then you must make sure that the internal pull-up is disabled (otherwise there will be additional pointless current through the internal pull-up).

If you connect it to VCC with a 1.8MOhm resistor, then there is no need to take care of the internal pull-up configuration.

If you leave it floating (not recommended), then you must enable the internal pull-up.

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BQ27425-G2A: BIN pin connection on when Battery Detection is not necessary