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YM-178 5V 2.1A Power bank digital LCD PCB 2 USB HQ Fast Charger Circuit Board

This PCB YM-178 comes with protection function: Charging overcharge protection,
over-discharge protection, over-current protection.
Intelligent output device after charging full, automatically stop charging,
to prevent mobile phones overcharge.Output voltage and current stable, will cause no harm to user devices.
This PCB contains both step up booster 3.7V to 5V and step down buck 5V to 4.2V converter. it  charges 3.7V battery cell to 4.2V.
The circuit board is connected to the battery negative B-, B + is the positive, do not
connecting reversed, connecting reversed will burn the board, the battery is connected
in parallel welding, assembling battery. Note that the insulation between the battery and the
circuit board, battery lead not to touch the circuit board, so as not to cause a short circuit.


Power bank PCB YM-178
Size: 55x20x5mm Length width height
Micro USB input: 5V 1A or 2A
USB Output: 5V 2.1A / 5V 1A(Dual USB interface)
Charging display: intelligent digital display
Digital LCD display Capacity display range:1% to 100% 
USB output voltage: 5V
USB output current 2.1A
Batteries Type: liquid lithium-ion batteries (18650)