Descriptions: _x000D_ 1. Nominal 12V (10.8V 11.1V) full charge voltage 12.6V lithium battery .3 string lithium battery charge management board.3A high current intelligent trickle, constant current, constant voltage charging management board._x000D_ _x000D_ 2. Solar cell maximum power point tracking (MPPT) is to ensure that the light intensity changes, the photovoltaic cells have been the maximum output power to take full advantage of solar energy. In general, it is necessary to use the switch mode DC-DC converter to achieve MPPT function, to maintain the output voltage and charge current product (output power) to maximize. _x000D_ 3. CN3722 is the use of switching buck mode DC-DC conversion way to achieve the maximum power point tracking function of photovoltaic cells, the input voltage up to 25V, very suitable for input voltage and battery voltage difference between the relatively large applications. _x000D_ _x000D_ _x000D_ Features: _x000D_ High-end technology MPPT solar maximum power tracking charge management chip, with trickle, constant current, constant voltage charging management. _x000D_ The use of imported high-frequency low-conduction resistance double MOS tube, high current diode, high efficiency flat high-power inductors, alloy current detection resistor. _x000D_ The large aluminum cooling fin at the bottom, ensure it keep stability working at the high current._x000D_ _x000D_ High-speed and efficient way of charging, heat small, fast. _x000D_ Dual status indicator light, no battery when the red light flashes green light is always on, charging red light, full of self-stop while the green light. _x000D_ _x000D_ _x000D_ Specifications: _x000D_ Input voltage: 18V nominal solar panels (no load about 21V solar panels) _x000D_ Output voltage: nominal 12V (10.8V 11.1V) filled with voltage 12.6V lithium battery, 3 string lithium battery charge management _x000D_ Output current: maximum constant current 3A (Charge current > 2A, please add heat dissipation) _x000D_ Wiring method: Welding plate _x000D_ IN + : input positive, IN - : input negative (SOLAR) _x000D_ BAT+: battery positive, BA-: battery negative _x000D_ Size:45* 31mm/1.77*1.22inch _x000D_ _x000D_ _x000D_ Package Included: _x000D_ 1 x MPPT Solar Panel Controller _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_