CN3791 MPPT Solar Panel 3.7V 4.2V DC-DC Regulator Controller Module 6V 9V 12V 2A

# CN3791 MPPT Solar Charger (Single-Cell Lithium Battery Charging Management) 

## 1. Product Parameters 

- Input Voltage: Select the corresponding module (6V/9V/12V) based on the nominal voltage of the solar panel. 

- Output Voltage: Designed for single-cell lithium batteries (nominal 3.7V, full-charge cut-off 4.2V). 

- Interface: 2pin PH2.0/JST connector. 

- Operating Temperature Range: －40℃ to ＋85℃. 

- Dimensions (Length×Width×Height): 45×20×9.5mm.

## 2. Product Features 

- Equipped with solar panel **Maximum Power Point Tracking (MPPT)** function, effectively improving solar energy utilization. 

- Provides complete charging management for single-cell lithium batteries (nominal voltage 3.7V, full-charge cut-off voltage 4.2V). 

- Maximum charging current up to 2A. 

- PWM switching frequency: 300KHz. 

- Constant voltage charging voltage: 4.2V±1%. 

- Constant current charging current is set by an external resistor. 

- Supports trickle charging for deeply discharged batteries, ensuring safe and sufficient charging. 

- Has automatic recharging function: Reactivates charging when the battery voltage drops after full charge. 

- Equipped with charging status and charge completion status indicators for intuitive monitoring. 

- Features soft-start function to avoid inrush current damage to components during startup. 

- Includes overvoltage protection at the battery terminal to prevent battery damage from excessive voltage. 

## Important Note 

If the CN3791 MPPT solar charger is the **9V version**, a solar panel with an **operating voltage of 9V** must be used (matching the module version to the solar panel voltage is mandatory).