DS1307N IC DIP8 MAXIM RTC DS1307N

Product Overview

The CN3791 is a high-efficiency, PWM switch-mode lithium-ion battery charge controller explicitly engineered for photovoltaic power sources. It features an intelligent Maximum Power Point Tracking (MPPT) function that uses a simple external resistor divider to continuously regulate the solar panel's voltage, ensuring it operates at its peak power output under varying sunlight conditions. The device handles a complete autonomous charge cycle—including trickle charging for deeply discharged cells, programmable constant-current charging, and high-accuracy constant-voltage regulation—while automatically dropping into a low-power sleep mode when sunlight is unavailable.

Core Specifications

• Manufacturer: Consonance (Shanghai Consonance Electronics)

• Base Part Number: CN3791

• Package Type: Space-saving 10-pin SSOP (SSOP-10)

• Function: Standalone Switch-Mode Solar Charger for Single-Cell Li-ion Batteries with MPPT

• Input Voltage Range: Wide 4.5V to 28V operational range (optimized for standard solar panel configurations)

• Maximum Charge Current: Up to 4A (externally programmable via a single current-sense resistor)

• PWM Switching Frequency: High 300 kHz frequency to allow for small external inductors

• Constant Voltage Regulation: Fixed 4.2V with an accuracy tolerance of ±1%

• Control Interface: Constant-voltage MPPT tracking set via an external resistor divider connected to the dedicated MPPT pin (internally regulated to 1.205V)

• Protection Features: Integrated battery overvoltage protection, automatic recharge, soft-start circuitry, under-voltage lockout (UVLO), and LED status/end-of-charge indications