Monolithic Power Systems Inc. MP2631DQ-LF-P

Overview

MP2631DQ-LF-P from Monolithic Power Systems is a linear single-cell Li-ion/Li-polymer battery charger with integrated 5V/10mA high-voltage LDO, 28V input surge tolerance, programmable 200mA–1A charge current, and OVP-triggered automatic disconnect at >7V. It delivers ±0.75% battery voltage regulation and <1µA reverse leakage, used in compact portable electronics requiring dual power-path management.

For engineers reviewing the MP2631DQ-LF-P datasheet, MP2631DQ-LF-P pinout, MP2631DQ-LF-P application, or MP2631DQ-LF-P equivalent, key selection criteria include input surge rating (28V), LDO enable behavior across VIN range (ON at 3–7V, cutoff >7V), thermal shutdown threshold (105–135°C), and CC/CV termination accuracy (±0.75% VBATT).

Technical Context

The MP2631DQ-LF-P implements a linear charging architecture with separate constant-current (CC) and constant-voltage (CV) stages, where charge current is set by an external resistor on ISET (100–1000mA range) and CV termination occurs at 4.20V ±0.04V. Trickle mode activates below 2.6V with 5–15% ICHG current.

Its integrated LDO operates independently of SHDN state, remains active for VIN = 3–7V, enters dropout below 5.1V, and shuts off above 7.0V via OVP circuitry that simultaneously disconnects both charger and LDO paths. ACOK and CHG open-drain indicators provide real-time system-level status reporting.

Key Specifications

Pinout & Package

MP2631DQ-LF-P uses a 10-pin 3mm × 3mm QFN package with exposed thermal pad (pin 5). The package supports high thermal dissipation (θ_JA = 50°C/W) and requires soldering the exposed pad to a solid ground plane for safe operation at full 1A charge current.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ24075RGTR and TP4056, MP2631DQ-LF-P uniquely integrates 28V surge tolerance, 5V/10mA LDO, and dual open-drain status outputs in a 3×3mm QFN-reducing total component count by up to 5 parts while enabling robust system supervision in space-constrained designs.

Availability

MP2631DQ-LF-P is available at Aetrix Electronics and suitable for cell phones, digital cameras, smart phones, and MP3 players requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for MP2631DQ-LF-P 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

Monolithic Power Systems (MPS) is a fabless semiconductor company specializing in high-performance analog and power ICs, with core expertise in DC/DC converters, battery management, and motor drivers.

The MP2631 product line targets portable consumer electronics needing highly integrated, thermally robust linear chargers with auxiliary power capability-designed to replace multi-component solutions in space- and cost-sensitive applications.

FAQ

What is the maximum input voltage the MP2631DQ-LF-P can safely withstand?

The MP2631DQ-LF-P is rated for absolute maximum input voltage of 28V, with built-in surge protection that automatically disconnects both charger and LDO when VIN exceeds 7.0V. This allows direct use with unregulated adapters or automotive USB ports without external TVS diodes.

How does the LDO behave when the SHDN pin is asserted high?

When SHDN is high, the charger is disabled but the LDO remains active as long as VIN stays between 3V and 7V. If VIN rises above 7.0V, the OVP circuit cuts off the LDO output regardless of SHDN state-ensuring system safety even during shutdown.

Can the MP2631DQ-LF-P charge a deeply discharged battery below 2.6V?

Yes-it initiates trickle charge at 5–15% of the programmed ICHG (e.g., 50–150mA for 1A setting) until battery voltage reaches 2.6V, then transitions to constant-current mode. This prevents lithium plating and extends cycle life in low-V_BATT recovery scenarios.

What thermal protection mechanism does the MP2631DQ-LF-P use?

The device employs soft thermal shutdown with activation at 105–135°C (typ. 120°C) and 10°C hysteresis. Unlike hard shutdown, it gradually reduces charge current above 110°C to maintain partial functionality while preventing die damage in thermally constrained layouts.

Is the ACOK pin compatible with 1.8V logic microcontrollers?

Yes-ACOK is an open-drain output with 4mA sink capability and no internal pull-up. When pulled up to 1.8V externally, it reliably signals "power good" (low) for VIN between 2.1V and 7.0V, enabling direct interface with low-voltage MCUs without level-shifting.

How is charge current programmed, and what resistor yields 1A?

Charge current is set by connecting ISET (pin 8) to GND via a precision resistor. Per Table 1, a 1.55kΩ resistor programs 1000mA nominal current. Tolerance and temperature drift cause ±13% variation, so 1% metal-film resistors are recommended for production accuracy.

Does the MP2631DQ-LF-P support automatic recharge, and at what voltage?

Yes-it automatically restarts charging when battery voltage falls to 4.0V (±100mV hysteresis) after full-charge termination. This feature maintains battery readiness without host firmware intervention, ideal for devices with intermittent usage patterns.