Microchip Technology MCP73831-2ATI/MC

Overview

MCP73831-2ATI/MC from Microchip Technology is a fully integrated linear lithium-ion/polymer battery charge management controller in an 8-lead 2 mm × 3 mm DFN package with exposed thermal pad. It delivers ±0.75% voltage regulation at 4.20 V, programmable charge current from 15 mA to 500 mA via single PROG resistor, and features reverse discharge protection, thermal regulation, and tri-state STAT output. It is designed for USB-powered portable devices requiring compact, cost-effective, single-cell charging.

For engineers reviewing the MCP73831-2ATI/MC datasheet, MCP73831-2ATI/MC pinout, MCP73831-2ATI/MC application, or MCP73831-2ATI/MC equivalent, key selection criteria include its fixed 4.20 V regulation accuracy, thermal foldback behavior above 150°C, preconditioning threshold at 66.5% of VREG, and compatibility with low-ESR ceramic output capacitors ≥4.7 µF.

Technical Context

The MCP73831-2ATI/MC implements a constant-current/constant-voltage (CC/CV) charge algorithm with factory-set 4.20 V regulation (±0.75%), selectable preconditioning (10%/20%/40% or disabled), and end-of-charge termination at 5% of programmed I_REG. Its internal P-channel MOSFET pass transistor has 350 mΩ typical R_DS(on) at 105°C, enabling efficient linear regulation while supporting automatic power-down when VDD falls below UVLO thresholds (3.3–3.6 V start, 3.2–3.5 V stop).

Thermal regulation begins before junction temperature reaches 150°C shutdown, dynamically reducing charge current to maintain reliability under high ambient or high-power conditions. The device operates across –40°C to +85°C ambient, with die temperature monitored internally and hysteresis of 10°C between thermal shutdown and recovery.

Key Specifications

Pinout & Package

Package: 8-Lead, 2 mm × 3 mm DFN with exposed thermal pad (EP), EP electrically connected to VSS and must be soldered to PCB ground plane for thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar linear Li-ion charge management applications.

Compared with BQ24075RGTR and TP4056, the MCP73831-2ATI/MC provides superior voltage accuracy (±0.75% vs. ±1% or ±1.5%), factory-configurable preconditioning, and active thermal regulation-making it optimal for space-constrained, thermally sensitive, and high-reliability Li-ion charging where precision and safety margins are critical.

Availability

MCP73831-2ATI/MC is available at Aetrix Electronics and suitable for USB-powered portable devices, wearable health monitors, industrial handheld terminals, smart home sensors, and Bluetooth audio accessories requiring stable component supply and long-term production continuity.

Supply support for MCP73831-2ATI/MC includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology Inc. is a leading provider of microcontrollers, analog components, and Flash-IP solutions, serving automotive, industrial, communications, and consumer markets with high-reliability silicon and development tools.

The MCP73831/2 product line was engineered for cost-sensitive, space-limited portable electronics requiring fully integrated, USB-compliant single-cell Li-ion/Li-polymer charging with minimal external components and robust thermal management.

FAQ

What is the exact voltage regulation accuracy of the MCP73831-2ATI/MC?

The MCP73831-2ATI/MC provides a fixed 4.20 V regulation voltage with a tolerance of ±0.75% over –40°C to +85°C ambient temperature. This specification is guaranteed in production testing and ensures consistent, safe termination for standard lithium-ion cells without requiring external calibration or trimming circuits. The MCP73831-2ATI/MC achieves this accuracy using an internal bandgap reference and precision feedback network.

How does the MCP73831-2ATI/MC handle thermal regulation during charging?

The MCP73831-2ATI/MC continuously monitors its die temperature and begins reducing charge current before reaching 150°C thermal shutdown. This dynamic foldback optimizes charge time while preventing thermal runaway or permanent damage. For example, with R_PROG = 2 kΩ (500 mA nominal), current decreases gradually above ~105°C, maintaining safe operation even under high ambient or poor PCB heatsinking. The MCP73831-2ATI/MC resumes full current only after cooling by ~10°C.

What is the function of the PROG pin on the MCP73831-2ATI/MC?

The PROG pin on the MCP73831-2ATI/MC serves dual functions: (1) setting fast charge current (I_REG) via resistor to VSS (2 kΩ–67 kΩ → 500 mA–15 mA), and (2) enabling/disabling the entire charger. Floating PROG disables the MCP73831-2ATI/MC, reducing supply current to 25 µA and limiting reverse discharge to <2 µA. This makes PROG a hardware shutdown control usable for battery disconnect or system-level power gating.

Does the MCP73831-2ATI/MC support automatic recharge, and how is the threshold set?

Yes, the MCP73831-2ATI/MC supports automatic recharge with a factory-set threshold of 94.0% of VREG (≈3.95 V for 4.20 V version). When battery voltage drops below this level in Charge Complete mode, the device restarts the full CC/CV cycle. This threshold is not user-adjustable but is optimized for typical Li-ion self-discharge rates and ensures timely top-up without premature cycling. The MCP73831-2ATI/MC maintains this behavior across its full operating temperature range.

What package type and thermal characteristics apply to the MCP73831-2ATI/MC?

The MCP73831-2ATI/MC uses an 8-lead 2 mm × 3 mm DFN package with an exposed thermal pad (EP) internally connected to VSS. On a 4-layer PCB with natural convection, its junction-to-ambient thermal resistance (θ_JA) is 76°C/W - significantly lower than SOT-23 alternatives. To achieve rated performance, EP must be soldered to a PCB ground plane with ≥4 thermal vias; failure to do so risks premature thermal regulation and reduced charge current.