Microchip Technology MCP73828-4.1VUATR

Overview

MCP73828-4.1VUATR from Microchip Technology is a linear single-cell Li-ion battery charge management controller in an 8-pin MSOP package, featuring ±1% voltage regulation at 4.1 V, programmable fast-charge current via external sense resistor, automatic preconditioning for deeply depleted cells, and integrated temperature monitoring via THERM pin. It is used in space-constrained portable electronics requiring safe, autonomous charging.

For engineers reviewing the MCP73828-4.1VUATR datasheet, MCP73828-4.1VUATR pinout, MCP73828-4.1VUATR application, or MCP73828-4.1VUATR equivalent, key selection criteria include its fixed 4.1 V regulation (optimized for coke-anode Li-ion), open-drain CD10 charge-complete indicator, VDRV-driven external P-channel MOSFET control, and thermal shutdown behavior tied to 113 mV / 839 mV THERM thresholds.

Technical Context

The MCP73828-4.1VUATR implements a three-phase charge algorithm-preconditioning (foldback current at ~43% of peak), controlled-current fast charge, and constant-voltage regulation-with internal voltage reference accuracy better than ±1% over –20°C to +85°C. Its analog control loop uses VSNS for current sensing and VBAT for cell voltage feedback, while digital logic manages SHDN enable/disable and CD10 state transitions.

Thermal safety is enforced via continuous THERM pin monitoring with factory-trimmed 113 mV (low) and 839 mV (high) thresholds, corresponding to typical NTC thermistor-based ranges like –0.5°C to 44.2°C. The device enters automatic power-down when VIN falls below VBAT, limiting battery drain to ≤0.7 µA in shutdown mode.

Key Specifications

Pinout & Package

Package: 8-pin MSOP (3 mm × 3 mm, 0.65 mm pitch), exposed pad optional for thermal relief.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP73828-4.1VUATR, the MCP73828-4.2VUATR offers identical functionality but targets different battery chemistries, while the BQ24040DRVR trades external MOSFET flexibility and precise dual-threshold thermal control for integration and reduced BOM count - making it less suitable for 4.1 V coke-anode systems requiring strict voltage compliance.

Availability

MCP73828-4.1VUATR is available at Aetrix Electronics and suitable for personal data assistants, cellular telephones, and hand-held instruments requiring stable component supply, long-term lifecycle support, and guaranteed authenticity for production builds.

Supply support for MCP73828-4.1VUATR 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 is a U.S.-based semiconductor manufacturer specializing in microcontrollers, analog devices, and interface ICs, with a focus on reliability, longevity, and design-in support for industrial and consumer applications.

The MCP73828 product line delivers compact, standalone linear Li-ion charge management for cost-sensitive, space-constrained portable electronics - designed specifically to simplify battery safety compliance without host processor dependency.

FAQ

What is the exact voltage regulation setpoint for MCP73828-4.1VUATR, and how accurate is it?

The MCP73828-4.1VUATR is factory-trimmed to regulate at 4.1 V with a maximum deviation of ±1% over the full –20°C to +85°C operating temperature range and 4.5 V to 5.5 V input supply. This corresponds to a guaranteed range of 4.059 V to 4.141 V at 25°C, ensuring compatibility with coke-anode lithium-ion cells that require strict 4.1 V termination.

How does the MCP73828-4.1VUATR handle deeply discharged batteries?

The MCP73828-4.1VUATR initiates automatic preconditioning when VBAT falls below ~2.4 V, applying a foldback current scaled to approximately 43% of the programmed peak charge current. This low-current phase safely restores voltage in deeply depleted cells while minimizing heat generation in the external P-MOSFET, preventing damage and extending battery life.

What are the THERM pin voltage thresholds, and how do they affect operation?

The MCP73828-4.1VUATR monitors the THERM pin with two factory-set thresholds: 113 mV (lower) and 839 mV (upper). If the voltage at THERM falls outside this window - indicating out-of-range battery temperature - charging is immediately suspended. A 10 kΩ resistor from THERM to GND disables this function entirely.

Can MCP73828-4.1VUATR be used without a microcontroller?

Yes, the MCP73828-4.1VUATR is designed for stand-alone operation: SHDN can be tied to VIN for automatic enable, CD10 drives an LED directly for status indication, and all charge phases (preconditioning, CC, CV) execute autonomously. No firmware or host control is required for basic charging functionality.

What external components are mandatory for basic operation of MCP73828-4.1VUATR?

Four components are mandatory: (1) an external P-channel MOSFET (e.g., NDS8434) driven by VDRV; (2) a sense resistor (RSENSE) between VIN and MOSFET source to set charge current; (3) ≥10 µF capacitor from VBAT to GND for loop stability; and (4) ≥10 µF capacitor from VIN to GND. THERM and CD10 may be left unconnected only if temperature monitoring and charge-complete indication are omitted.