The Lipo charging module from Adafruit impresses with its compact design and ease of use. Plug the module into a USB port and connect a 3.7 V or 4.2 V Li-Ion or Li-Po battery to the board via the JST socket. Two LEDs indicate the current charging process. The red LED lights up while charging. When the battery is fully charged, the green LED lights up. The charging process takes place in three stages: First, the preconditioning takes place, then the constant current fast charging and finally it is fully charged with a constant voltage. The charging current is limited to 100 mA as standard in order to guarantee functionality with Allen batteries and USB ports. If larger capacities of 500 mAh and higher are to be charged, you can close the soldered connection on the back of the board in order.
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