Description
The MCP73871 device is a fully integrated linear solution for system load sharing and Li-Ion / Li-Polymer battery charge management with ac-dc wall adapter and USB port power sources selection. It’s also capable of autonomous power source selection between input or battery. Along with its small physical size, the low number of required external components makes the device ideally suited for portable applications.
The MCP73871 device automatically obtains power for the system load from a single-cell Li-Ion battery or an input power source (ac-dc wall adapter or USB port). The MCP73871 device specifically adheres to the current drawn limits governed by the USB specification. With an ac-dc wall adapter providing power to the system, an external resistor sets the magnitude of 1A maximum charge current while supports up to 1.8A total current for system load and battery charge current.

Features
• Integrated System Load Sharing and Battery Charge Management
   - Simultaneously Power the System and Charge the Li-Ion Battery
   - Voltage Proportional Current Control (VPCC) ensures system load has priority over Li-Ion battery charge current
   - Low-Loss Power-Path Management with Ideal Diode Operation
• Complete Linear Charge Management Controller
   - Integrated Pass Transistors
   - Integrated Current Sense
   - Integrated Reverse Discharge Protection
   - Selectable Input Power Sources: USB Port or AC-DC Wall Adapter
• Preset High Accuracy Charge Voltage Options:
   - 4.10V, 4.20V, 4.35V or 4.40V
   - ±0.5% Regulation Tolerance
• Constant Current / Constant Voltage (CC/CV) Operation with Thermal Regulation
• Maximum 1.8A Total Input Current Control
• Resistor Programmable Fast Charge Current Control: 50 mA to 1A
• Resistor Programmable Termination Set Point
• Selectable USB Input Current Control
   - Absolute Maximum: 100 mA (L) / 500 mA (H)
• Automatic Recharge
• Automatic End-of-Charge Control
• Safety Timer With Timer Enable/Disable Control
• 0.1C Preconditioning for Deeply Depleted Cells
• Battery Cell Temperature Monitor
• Undervoltage Lockout (UVLO)
• Low Battery Status Indicator (LBO)
• Power-Good Status Indicator (PG)
• Charge Status and Fault Condition Indicators
• Numerous Selectable Options Available for a Variety of Applications:
   - Refer to Section 1.0 “Electrical Characteristics” for Selectable Options”
   - Refer to the “Product Identification System” for Standard Options
• Temperature Range: -40°C to +85°C
• Packaging: 20-Lead QFN (4 mm x 4 mm)

Applications
• GPSs / Navigators
• PDAs and Smart Phones
• Portable Media Players and MP3 Players
• Digital Cameras
• Bluetooth Headsets
• Portable Medical Devices
• Charge Cradles / Docking Stations
• Toys