Efficient and Intelligent Dual-Cell Charging with the MCP73223T-C2SI/MF

The Microchip MCP73223T-C2SI/MF is a highly integrated charge management controller designed for 2-series Li-Ion or Li-Polymer battery cells. This device simplifies the design of charging systems by combining multiple critical functions into a compact 10-lead DFN package, making it an ideal solution for space-constrained portable applications.

At its core, the controller employs a constant-current/constant-voltage (CC/CV) charging algorithm with thermal regulation to optimize charge time and maintain safety. It can accept a wide input voltage range of 4.5V to 16V, providing significant flexibility for various power sources, including AC-DC adapters and USB ports. A key feature is its ability to accurately charge two series cells to a pre-set 8.4V (4.2V per cell) with ±0.75% voltage accuracy, ensuring maximum battery capacity and longevity.

The MCP73223T-C2SI/MF enhances system safety with multiple built-in protections. These include timer-based safety limits, thermal shutdown, and reverse discharge protection, which prevents battery drain when the input voltage is removed. Its integrated pass MOSFETs and current sense circuit eliminate the need for many external components, reducing both the bill of materials (BOM) and overall PCB footprint.

The charge status is communicated to the host system via two open-drain status outputs, indicating whether the controller is in charge, standby, or fault condition. This allows for simple LED indicators or microcontroller communication. The device's thermal regulation loop actively reduces the charge current if the die temperature exceeds ~145°C, protecting itself and the surrounding components during high-power operation or elevated ambient temperatures.

ICGOOODFIND: The MCP73223T-C2SI/MF stands out as a robust, fully-integrated, and space-efficient solution for dual-cell lithium battery charging, offering high accuracy, comprehensive protection, and design simplicity for a wide range of portable electronics.

Keywords: Dual-Cell Li-Ion Charger, Constant-Current/Constant-Voltage, Integrated Pass FET, Thermal Regulation, Charge Status Indicator