ME4057ASPG-N

ME4057-N is a single-cell lithium battery charge management IC featuring constant voltage and constant current charging. The maximum charging current can reach 1A, with no external diode or current sense resistor required. Two open-drain status indicator outputs are included: a charging status indicator and a battery fault status indicator. An internal thermal feedback circuit automatically reduces the charging current when the temperature exceeds 145°C, allowing users to maximize the IC's power handling capability while ensuring reliability. Charging begins when the input voltage exceeds the undervoltage lockout threshold and the enable pin is pulled high. If the battery voltage is below 2.9V, pre-charging is performed at a low current; above 2.9V, the IC switches to constant current mode, with the charging current determined by the resistor between the PROG pin and GND. As the battery voltage approaches 4.2V, the charging current gradually decreases; when the current drops to 1/10 of the constant current value, the charging cycle ends. When the battery voltage falls below the recharge threshold, a new charging cycle begins automatically. The internal high-precision voltage reference, error amplifier, and resistor divider network ensure the battery terminal regulation voltage accuracy is within 1%, meeting the requirements of Li-ion and Li-polymer batteries. When the input voltage is removed or falls below the battery voltage, the charger enters sleep mode, with battery terminal leakage current as low as 2µA, extending standby time. Pulling the enable pin low disables charging.

Applications

• Mobile phones
• Digital cameras
• MP3, MP4 players
• Bluetooth-enabled portable devices
• USB power supplies, adapters

Key features

• Operating voltage up to 9V
• Reverse battery protection
• Programmable charge current up to 1A
• No MOSFET, sense resistor, or isolation diode required
• Single-cell complete linear charger in ESOP8 package
• CC/CV switching with internal thermal feedback protection
• Fixed charge termination voltage of 4.2V / 4.13050V (500mAh fixed battery) with ±1% accuracy
• Automatic recharge function
• Dual charge status output with no-battery and fault status indication
• C/10 charge termination
• Standby current 55μA
• 2.9V trickle charge threshold
• Soft-start inrush current limiting
• Battery temperature monitoring