This is a 2-in-1 boost charger model with very small dimension (25 x 16 x 5 mm).
After connecting to a 3.7V Li-Po battery (not included), it can work like a power bank.
It has a button on board to turn on/off the output voltage (DC 5V). Single-clicking the button will turn on the output, while double-clicking the button will turn off the output.
There are 4 red LEDs on the board to indicate the charging progress and discharging status.
If the load current is less than 50 mA, it will automatically turn off the output after 30 seconds. If this board needs to continue working with small load, you can connect the “KEY” pad on the board to a micro controller, and give it a low pulse for every 25 seconds, that way it will continue the output.
Battery Voltage: 3~4.2V
Battery Quiescent Current: ~0.3 mA
Input (Charging) Voltage: 4.5~5.5V (5V recommended)
Input (Charging) Current: 0~2A (automatically adjust)
Output (Discharging) Voltage: 5V
Output (Discharging) Current: up to 2A
Boost Efficiency: >90%