Microchip Technology MCP73838T-FCI/MF

Overview

MCP73838T-FCI/MF from Microchip Technology is a fully integrated linear Li-Ion/Li-Polymer battery charge management controller with autonomous AC adapter or USB port source selection, ±0.5% voltage regulation accuracy, 4.20V fixed charge voltage, 1000 mA max AC charge current, and Timer Enable (TE) pin for safety timer control. It operates in portable devices requiring dual-source charging with thermal regulation and battery temperature monitoring.

For engineers reviewing the MCP73838T-FCI/MF datasheet, MCP73838T-FCI/MF pinout, MCP73838T-FCI/MF application, or MCP73838T-FCI/MF equivalent, this page delivers verified technical context, real-world use cases, pin-level design meaning, and validated alternative options for Li-ion charging system design and BOM optimization.

Technical Context

The MCP73838T-FCI/MF implements a CC/CV charge algorithm with factory-set 4.20V regulation, selectable preconditioning and termination thresholds, and thermal regulation via internal die temperature sensing. Its autonomous power source selection logic prioritizes VAC over VUSB, with UVLO thresholds of 4.15V (start) and 4.1V (stop) for AC input.

It features dual PROG inputs: PROG1 sets AC adapter current (15–1000 mA via resistor), while PROG2 selects USB current (100 mA or 500 mA via logic level). The TE pin enables/disables the safety timer (4/6/8 hr options), distinguishing it from the MCP73837 variant which uses PG instead.

Key Specifications

Pinout & Package

Package: 10-Lead 3 mm × 3 mm DFN with exposed thermal pad (EP), internally connected to VSS. Requires soldering EP to PCB ground plane for thermal and electrical integrity.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP73837T-FCI/MF, the MCP73838T-FCI/MF trades PG functionality for TE-based timer control - essential for safety-critical charging. Versus BQ24075RGTR, it offers tighter voltage tolerance (±0.5% vs ±1.0%) and lower thermal resistance (41°C/W vs ~65°C/W), but lacks system power path capability.

Availability

MCP73838T-FCI/MF is available at Aetrix Electronics and suitable for smartphone charging circuits, portable medical monitors, Bluetooth headset docks, and digital camera battery chargers requiring stable component supply, long-term lifecycle support, and AEC-Q200–compatible manufacturing traceability.

Supply support for MCP73838T-FCI/MF 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 leading provider of microcontrollers, analog components, and battery management ICs, with design centers worldwide and ISO 9001-certified manufacturing.

The MCP7383x family was designed specifically for space-constrained portable Li-ion/Li-polymer charging applications requiring autonomous dual-source selection, high voltage accuracy, and integrated safety features - targeting consumer, medical, and industrial handheld devices.

FAQ

What is the exact charge voltage setting for the MCP73838T-FCI/MF?

The MCP73838T-FCI/MF is factory-configured for 4.20V constant-voltage regulation with ±0.5% tolerance across -5°C to +55°C. This value is fixed and not user-adjustable; other variants (e.g., MCP73838T-FCT/MF) offer 4.35V or 4.40V. The 4.20V setting matches standard single-cell Li-ion chemistry requirements.

How does the TE pin function on the MCP73838T-FCI/MF?

The TE (Timer Enable) pin on the MCP73838T-FCI/MF is an active-low input that enables or disables the internal safety timer. When pulled to VSS (logic low), the timer runs (4/6/8 hr options per device variant); when pulled to VDD (logic high), the timer is disabled. This pin replaces the PG output found on the MCP73837, making TE a key differentiator for the MCP73838T-FCI/MF.

Can the MCP73838T-FCI/MF charge batteries at temperatures below 0°C?

The MCP73838T-FCI/MF monitors battery temperature via the THERM pin using a 50 µA bias current for NTC thermistors. While the IC operates from -40°C to +85°C ambient, charging is suspended if thermistor voltage indicates cell temperature outside the safe range - typically below 0°C or above 45°C - as defined by the external NTC network. No charging occurs outside those bounds.

What is the maximum AC adapter input voltage supported by the MCP73838T-FCI/MF?

The MCP73838T-FCI/MF supports AC adapter input voltages from (V_REG + 0.3V) up to 6.0V. For its 4.20V regulation, this means VAC can range from 4.5V to 6.0V. Absolute maximum rating is 7.0V, but operation above 6.0V violates specification limits and may cause premature wear or failure. Input ripple must be limited per PSRR specs (≥52 dB at 10 kHz).

Does the MCP73838T-FCI/MF require external MOSFETs for charging control?

No, the MCP73838T-FCI/MF integrates all necessary pass transistors, current sensing, and reverse discharge protection. Its internal FET has 350 mΩ typical R_DS(on) at 105°C, enabling up to 1000 mA charging without external switches. This eliminates the need for discrete MOSFETs, sense resistors, or blocking diodes - reducing total solution size and component count versus discrete charger designs.