Microchip Technology MCP73833T-CNI/MF

Overview

MCP73833T-CNI/MF from Microchip Technology is a standalone linear Li-ion/Li-polymer battery charge management controller in a 10-lead DFN-10 (3 mm × 3 mm) package. It delivers constant-current/constant-voltage charging with thermal regulation, 4.20 V ±0.75% voltage regulation, up to 1 A programmable charge current via external resistor, and integrated reverse discharge protection - designed for USB-powered portable devices requiring compact, reliable single-cell charging.

For engineers reviewing the MCP73833T-CNI/MF datasheet, MCP73833T-CNI/MF pinout, MCP73833T-CNI/MF application, or MCP73833T-CNI/MF equivalent, key selection criteria include its factory-set 4.20 V regulation, thermal-foldback behavior at >105°C junction temperature, dual open-drain STAT outputs for LED/microcontroller status indication, and PG output for input power-good signaling - all validated across –40°C to +85°C ambient operation.

Technical Context

The MCP73833T-CNI/MF implements a fully integrated linear charging architecture with an internal P-channel MOSFET pass transistor (R_DS(on) = 300 mΩ), precision 1.21 V reference generator, and ratiometric current sensing. Its preconditioning, fast-charge, constant-voltage, and automatic recharge states are governed by factory-trimmed thresholds - including 66.5% V_REG precondition voltage, 5% I_REG termination current ratio, and 94.0% V_REG recharge threshold - all operating without external microcontroller intervention.

Thermal regulation dynamically reduces charge current above ~105°C die temperature to prevent overheating, while independent thermistor monitoring (50 µA bias, 1.23 V / 0.25 V thresholds) suspends charging on NTC/PTC fault detection. The device enters automatic power-down when V_DD falls within 50 mV of V_BAT, limiting reverse discharge leakage to ≤2 µA.

Key Specifications

Pinout & Package

Package: DFN-10 (3 mm × 3 mm), exposed thermal pad (EP) electrically connected to VSS - requires soldered thermal land for thermal regulation performance and reliability.

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 MCP73833T-CNI/MF provides tighter voltage accuracy (±0.75%), factory-trimmed preconditioning and recharge thresholds, integrated thermal regulation, and dedicated PG signaling - making it optimal for USB-compliant, thermally managed, and safety-aware portable designs.

Availability

MCP73833T-CNI/MF is available at Aetrix Electronics and suitable for USB-powered portable devices, medical wearables, Li-ion battery backup systems, and USB-C accessory chargers requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for MCP73833T-CNI/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, FPGA, and mixed-signal semiconductors, with core expertise in embedded control and power management solutions.

The MCP73833/4 product line was designed specifically for space-constrained, cost-sensitive Li-ion/Li-polymer charging applications - emphasizing minimal external components, USB compliance, and robust thermal and safety features without firmware dependency.

FAQ

What is the factory-set voltage regulation for MCP73833T-CNI/MF?

The MCP73833T-CNI/MF has a factory-set constant-voltage regulation of 4.20 V ±0.75%, optimized for standard single-cell Li-ion and Li-polymer batteries. This value is laser-trimmed during manufacturing and cannot be adjusted externally. The MCP73833T-CNI/MF datasheet confirms this specification applies across the full –40°C to +85°C ambient temperature range, with load regulation of ≤0.30% over 10–100 mA output current.

How does the MCP73833T-CNI/MF handle thermal regulation during charging?

The MCP73833T-CNI/MF implements continuous thermal regulation by reducing charge current as junction temperature rises above ~105°C, based on its internal thermal sensor. Unlike thermal shutdown, this foldback behavior maintains charging - albeit at lower current - to optimize cycle time while preserving reliability. The device fully suspends charging only if die temperature exceeds 150°C, with automatic resumption after cooling by ~10°C.

Can MCP73833T-CNI/MF be used without a thermistor?

Yes, the MCP73833T-CNI/MF can operate without a thermistor: connect a 10 kΩ resistor from THERM to VSS to disable temperature monitoring. In this configuration, the device retains all core charging functions - CC/CV regulation, preconditioning, EOC, and automatic recharge - but loses over-temperature protection. The MCP73833T-CNI/MF datasheet explicitly permits this for applications where thermal fault detection is not required.

What is the function of the PG pin on MCP73833T-CNI/MF?

The PG (Power Good) pin on MCP73833T-CNI/MF is a pseudo open-drain output that sinks current when V_DD exceeds the UVLO threshold (≥3.55 V) and remains greater than V_BAT. It signals valid input power presence to system logic. Due to an internal diode path to V_DD, PG must only be pulled up to V_DD - never to a separate rail - to avoid unintended current paths. The MCP73833T-CNI/MF PG output is active-low and remains low during all normal charge states.

How is charge current programmed on MCP73833T-CNI/MF?

Charge current on MCP73833T-CNI/MF is programmed using a single resistor (R_PROG) from the PROG pin to VSS, per the equation I_REG = 1000 V / R_PROG (with R_PROG in kΩ and I_REG in mA). For example, a 1.0 kΩ resistor sets 1000 mA; a 10 kΩ resistor sets 100 mA. The MCP73833T-CNI/MF datasheet specifies R_PROG range of 1–20 kΩ for active charging, and >70 kΩ places the device in standby with <100 µA quiescent current.