This charger has LiIon charging functions via the input power source, either USB connector or separate input power at IN- and IN+. The LiIon battery should be connected to one of the BAT- pads and the BAT+ pad.
The charger also has built in protection of both current (max 3A) and under voltage (min 2.5V) when the battery is supplying power. The battery will be disconnected from the load at the under voltage point. The item to be powered should be connected between the P- and P+ pads.
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