Overview: CN3801 is a PWM buck single-cell lithium iron phosphate battery charge management integrated circuit that can be powered by solar panels. It independently manages the charging of a single-cell lithium iron phosphate battery and features a small package size, few external components, and ease of use. CN3801 has trickle, constant current, and constant voltage charging modes, making it ideal for lithium iron phosphate battery charge management. In constant voltage charging mode, CN3801 regulates the battery voltage to 3.625V; in constant current charging mode, the charging current is set by an external resistor. When the input power's current output capability decreases, the internal circuit can automatically track the maximum power point of the solar panel. Users do not need to consider the worst-case scenario and can maximize the use of the solar panel's output power, making it ideal for solar-powered applications. For deeply discharged batteries, when the battery voltage is below 66.5% (typical value) of the constant voltage charging voltage, CN3801 performs trickle charging with 17.5% of the set constant current charging current. In the constant voltage charging stage, the charging current gradually decreases, and when the charging current decreases to 16% of the constant current charging current, the charging ends. In the charging completion state, if the battery voltage drops to 91.66% of the constant voltage charging voltage, a new charging cycle automatically begins. When the input power is cut off or the input voltage is lower than the battery voltage, CN3801 automatically enters sleep mode. Other functions include input undervoltage lockout, battery overvoltage protection, and charging status indication. CN3801 is available in a 10-pin SSOP package.

Product Parameters

Main Functions: 4A single-cell lithium iron phosphate battery charge management integrated circuit with maximum power point tracking function for solar cells

Operating Mode: Switching

Battery Type: Lithium iron phosphate battery

Number of Batteries: 1

Output Voltage Range: 0V-3.6V

Input Voltage Range: 4.5V-30V

Maximum Charging Current: 4A

Operating Current: 1mA

Solar Power Supply: Yes

Thermal Modulation: No

Packaging Form: SSOP10

Switching Frequency: 300kHz

Built-in Power Tube: No

Applications ：

l Handheld devices

l Emergency lighting

l Backup battery applications

l Portable industrial and medical instruments

l Power tools

l Independent battery chargers

Features ：

l Maximum power point tracking function for solar panels

l Wide input voltage range: 4.5V to 28V

l Complete charge management for single-cell lithium iron phosphate batteries

l Charging current up to 4A

l PWM switching frequency: 300KHz

l Constant voltage charging voltage: 3.625V ± 40mV

l Constant current charging current set by external resistor

l Trickle charging for deeply discharged batteries

l Automatic recharging function

l Charging status and charging completion status indication

l Soft start function

l Overvoltage protection at the battery terminal

l Operating ambient temperature: -40°C to +85°C

l 10-pin SSOP package

l Lead-free product, RoHS compliant, halogen-free