The BQ27Z758 device can use the active low digital input ENAB pin to exit the device's SHELF and SHUTDOWN power modes. The digital input is connected to a weak internal pullup to VDD. A push-button can be connected to the ENAB pin to drive the pin to a low state for the device to exit SHELF or SHUTDOWN mode.

If the ENAB pin is connected directly to the device's GND reference (VSS), the BQ27Z758 device will not be able to enter SHELF or SHUTDOWN mode.

The ENAB pin can be left floating if using a push-button to exit SHELF or SHUTDOWN mode is not needed. The ENAB pin can also be left floating if the device needs the capability to enter SHELF or SHUTDOWN mode.