Monolithic Power Systems Inc. MP2635GR-P

Overview

MP2635GR-P from Monolithic Power Systems is a 2.0A switch-mode single-cell Li-ion/Li-polymer battery charger with integrated power path management (PPM), supporting simultaneous system power delivery and battery charging. It operates in charge mode (4.5–6V input), boost mode (up to 1.5A SYS output at 5V), and sleep mode, with programmable 4.2V/3.6V full-charge voltage, ±0.5% CV accuracy, and thermal regulation at 120°C - deployed in portable power banks and sub-battery systems.

For engineers reviewing the MP2635GR-P datasheet, MP2635GR-P pinout, MP2635GR-P application, or MP2635GR-P equivalent, key selection criteria include input current limit programming via ILIM, boost output current setting via OLIM, NTC-based battery temperature monitoring on pin 10, and dual-mode status indication via ACOK/CHG/BOOST pins for real-time system-level power arbitration.

Technical Context

The MP2635GR-P implements a synchronous buck-boost architecture with bidirectional power path control: in charge mode, it regulates input current (programmable up to 3A) and input voltage (via REG pin feedback) while executing trickle → constant-current → constant-voltage charge phases; in boost mode, it converts battery voltage (2.5–4.35V) to regulated 4.2–5.6V SYS output using MODE-pin-activated reverse operation.

Its dual-loop protection includes input over-current detection (3A threshold, 120µs blanking), SYS over-current limiting (programmable up to 1.5A), battery over-voltage shutdown at 103.3% of full-charge voltage, and thermal foldback activation at 120°C - all coordinated through an integrated analog control block without external microcontroller dependency.

Key Specifications

Pinout & Package

MP2635GR-P uses a QFN-24 (4mm × 4mm, 0.5mm pitch) package with exposed thermal pad (PGND, Pin 19). Pin functions are validated per Monolithic Power Systems Rev. 1.08 datasheet.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar single-cell switch-mode battery charger with power path management applications.

Compared with BQ25618RTWR and IP2326, MP2635GR-P uniquely combines 2.0A charge + 1.5A boost + input voltage regulation + NTC interface in one QFN-24 package - enabling fully autonomous, USB-agnostic power management without host firmware dependencies.

Availability

MP2635GR-P is available at Aetrix Electronics and suitable for power bank systems, USB-C portable monitors, and wireless earbud charging cases requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MP2635GR-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 mixed-signal ICs for power management, motion control, and automotive applications.

The MP2635GR-P belongs to MPS's battery management product line, designed specifically for space-constrained portable electronics requiring integrated charge + boost functionality with autonomous mode transitions and robust safety features.

FAQ

What is the function of the VB pin on MP2635GR-P?

The VB pin selects the battery full-charge voltage: connecting VB to GND configures 3.6V termination for LiFePO₄ cells, while leaving it floating or pulling it high sets 4.2V for standard Li-ion. This hardware-selectable option eliminates firmware configuration and supports dual-chemistry designs without component change.

How does MP2635GR-P handle input current limiting during simultaneous charge and system load?

MP2635GR-P uses its input current limit loop (programmed via ILIM resistor) to dynamically reduce charge current when system load increases - maintaining total input current within the programmed limit. This prevents USB port overcurrent faults while ensuring uninterrupted SYS power delivery.

Can MP2635GR-P operate without an external NTC thermistor?

Yes - the NTC pin (Pin 10) is optional. If left unconnected, battery temperature monitoring is disabled, but all other functions (charge, boost, protection) remain fully operational. For safety-critical applications, MPS recommends using NCP18XH103 or equivalent 10kΩ NTC with specified R-T curve.

What is the minimum battery voltage required to initiate boost mode?

Boost mode requires VBATT ≥ 2.9V to start - verified by internal weak-battery comparator. If battery voltage drops below 2.5V during boost operation, the device shuts down SYS output to prevent deep discharge and cell damage.

Does MP2635GR-P support automatic transition between charge and boost modes?

Yes - transition is fully autonomous. When ACOK goes low (input removed), and MODE is pulled high, MP2635GR-P immediately enters boost mode without external timing or control. When ACOK returns high, it transitions back to charge mode within 150µs, as confirmed in Figure 7 of the datasheet.

What is the purpose of the REG pin and how is it configured?

The REG pin provides feedback for input voltage regulation. A resistor divider from VIN to GND sets the regulation threshold (e.g., 4.7V); when input voltage sags, MP2635GR-P reduces charge current to maintain that voltage - protecting weak USB hosts from brownout during high-power system operation.

How is charge termination determined on MP2635GR-P?

Termination occurs when charge current falls to 5–17.5% of the programmed CC value (depending on ISET resistor), verified by the current-sense amplifier and internal comparator. A backup timer (programmed via TMR capacitor) enforces hard cutoff after 360 minutes to prevent overcharge of defective cells.