BENEFITS and FEATURES

• Wide VIN Range: 3.9V to 29V (No Dead Zone)

• Supports 2 to 5 Cell Lithium-ion Batteries

• Supports OTG Function (5V ~ 22.5V Input) with wide range of output voltages

• OTG output supports QC3.0 / USB PD + PPS output levels and transition times

• Programmable Frequency: 125KHz, 250KHz, 500kHz, and 1MHz

• 2V ~ 5.1V/100mA Programmable Output LDO

• Precision 0.5% Voltage Reference

• +/-4% Output Constant Current Regulation

• < 5 μA Leakage Current from Battery in Shipping Mode

• Programmable Charge Voltage via I2C

• Programmable Charge Current via Pin and I2C

• Programmable Soft-Start

• Programmable Safety Timer

• Battery Path Impedance Compensation

• JEITA Compliant

• Cycle-by-Cycle Current Limit

• Built in ADC for Temperature, Input and Output Volt-age and Current monitoring

• Thermal Regulation and Protection

• 25mΩ FET from VIN to SW1

• 25mΩ FET from SW2 to VOUT

• 35mΩ FET from SW1 to PGND

• 35mΩ FET from SW2 to PGND

• Low Output Ripple

• Thermally Enhanced 32-Lead 4mx4mm QFN

APPLICATIONS

• Multi Cell Battery Charger

• Portable Battery-Powered Devices

• Car Charger

• Power Bank

• 24V Industrial Applications

• Automotive Power Systems

• Multiple Power Source Supplies

• DC UPS

• Solar Powered Devices

• Solid-State Lighting

GENERAL DESCRIPTION

The ACT2861 is a buck-boost charger with 4 integrated MOSFETs. It offers a high efficiency, low component count, compact solution for 2 to 5 cell battery charging applications. It operates from a 3.9 V to 29 V input voltage range.

The 4 internal low resistance NMOS switches minimize the size of the application circuit and reduce power losses to maximize efficiency. Internal high side gate drivers, which only require two small external capacitors, simplify the design process. An advanced switch control algorithm allows the buck-boost converter to maintain output voltage regulation with input voltages that are above, below, or equal to the output voltage. Transitions between these operating modes are seamless and free of transients and subharmonic switching.

The ACT2861 is optimized to reduce input current in shipping, shutdown, and standby for applications that are sensitive to quiescent current draw, such as battery-powered devices.

Both the input and output voltages and currents can be configured by resistors and the I2C serial interface. The system can also be monitored and configured using I2C. The built-in ADC can read input/output voltages and currents and the die temperature. With an MCU, it can easy charge a multi-cell battery pack from a variety of input power sources.

The IC provides the standard battery charger and power supply safety features for system operation.

The ACT2861 is available in 32-pin, 4x4 mm QFN package.