Datasheet

this pin which will let you know when there's power output

Control Pins

There's two 'control' pins.

EN - this is the 'enable' pin. By default it is pulled 'high' to VBAT. To turn off the

booster, connect this pin to ground. The switch can be as small as you like, it is just a

signal. Contrast this to an inline power switch which would have to be able to handle up

to 2A of current! When the chip is disabled the output is completely disconnected

from the input.

LBO - not a leveraged buy out! this is the Low Battery Output. By default it is

pulled high to BAT but when the charger detects a low voltage (under 3.2V) the pin will

drop down to 0V. You can use this to signal when its time to shut down or alert the

user that the battery is low. There is also a red LED connected to this pin.

LEDs

There are two onboard LEDs. The Green LED sits next to the USB connector socket, and

indicates the 5V output power state. The Red LED is next to the battery JST port and

indicates when the battery voltage is below 3.2VDC