Monolithic Power Systems Inc. MPQ2451GT-33-AEC1-P

Overview

MPQ2451GT-33-AEC1-P from Monolithic Power Systems is an AEC-Q100 Grade 1 qualified, 36V-input, 2.2MHz synchronous step-down DC/DC converter with integrated 500mΩ high-side MOSFET, delivering up to 0.6A at fixed 3.3V output. It features 130µA quiescent current, internal soft-start, and current-mode control for automotive body electronics, infotainment power rails, and ADAS sensor modules.

For engineers reviewing the MPQ2451GT-33-AEC1-P datasheet, MPQ2451GT-33-AEC1-P pinout, MPQ2451GT-33-AEC1-P application, or MPQ2451GT-33-AEC1-P equivalent, this device supports high-frequency layout-constrained designs requiring low-noise 3.3V regulation from wide-input automotive batteries, with validated thermal shutdown, UVLO, and pulse-skipping efficiency optimization.

Technical Context

The MPQ2451GT-33-AEC1-P implements fixed-frequency (2.2MHz ±20%) peak-current-mode control with internal compensation, enabling stable operation with ceramic output capacitors without external loop components. Its bootstrap-driven high-side gate driver requires a 100nF BST–SW capacitor and supports duty cycles up to ~92% when VIN ≥ VOUT + 3V.

It integrates a precision current-limit comparator (750mA typ., 650mA min over −40°C to +125°C), under-voltage lockout (2.7V rising threshold), and thermal shutdown (150°C trip). The EN pin provides logic-level enable control with 1.35V–1.8V high-threshold and 400mV hysteresis, supporting system-level power sequencing.

Key Specifications

Pinout & Package

SOT23-6L package (2.9mm × 2.8mm × 1.3mm) with exposed pad for thermal enhancement; pin-compatible with QFN-6L variant but distinct land pattern and soldering profile.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar step-down converter applications.

Compared with MPQ2451GT-5-AEC1, the MPQ2451GT-33-AEC1-P offers identical reliability and layout compatibility but targets 3.3V-sensitive loads like sensors and low-voltage FPGAs; versus TPS62130A-Q1, it trades higher current for lower BOM count, smaller footprint, and simpler design-in - ideal for cost- and space-constrained automotive modules.

Availability

MPQ2451GT-33-AEC1-P is available at Aetrix Electronics and suitable for automotive body electronics, ADAS camera modules, infotainment USB hubs, and telematics control units requiring stable component supply with full AEC-Q100 traceability.

Supply support for MPQ2451GT-33-AEC1-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 design centers in the US, China, and Taiwan, and global manufacturing partnerships.

The MPQ2451 product line delivers compact, AEC-Q100-qualified DC/DC converters for automotive subsystems demanding high efficiency, small size, and robust transient response - targeting body electronics, infotainment, and ADAS power domains.

FAQ

What is the minimum input voltage required for reliable startup?

The MPQ2451GT-33-AEC1-P has a VIN UVLO rising threshold of 2.7V, but stable regulation requires ≥3.3V input per datasheet specifications. Below 3.3V, output voltage drops linearly and current limit degrades; cold-crank operation must maintain ≥3.3V at VIN for functional 3.3V output.

Can this IC drive a synchronous rectifier instead of a Schottky diode?

No - the MPQ2451GT-33-AEC1-P is an asynchronous buck converter with only a high-side MOSFET. It lacks a dedicated low-side gate driver output; external synchronous rectification requires a separate controller or a different MPS part such as MPQ4420A.

Is the 3.3V output adjustable using external resistors?

No - the OUT pin is internally connected to a fixed 3.3V resistor divider. There is no FB pin or external feedback option; output voltage cannot be adjusted. For adjustable output, consider MPQ2451DG-33-AEC1 with external resistor network.

What thermal derating applies in SOT23-6L package at 85°C ambient?

With θJA = 220°C/W, maximum power dissipation at TA = 85°C is (150°C − 85°C)/220°C/W = 295mW. At 12V input and 3.3V/0.6A output, losses ≈ 320mW - thus continuous 0.6A requires forced airflow or PCB copper pour to avoid thermal shutdown.

Does the device support forced PWM mode to eliminate audible noise?

No - the MPQ2451GT-33-AEC1-P automatically enters pulse-skipping mode below ~20% load; there is no pin or register to force continuous PWM. For noise-sensitive applications, select MPQ2451GG-33-AEC1 (QFN-6L) with lower thermal resistance and reduced vibration coupling.

How is the bootstrap capacitor charged during startup?

At power-on, the internal bootstrap regulator charges the BST–SW capacitor from VIN through a PMOS pass transistor when VIN − VSW > ~2.5V. Charging occurs during the off-time of the high-side switch; sufficient voltage headroom (VIN − VOUT > 3V) is required for reliable startup in high-duty-cycle conditions.

What is the recommended inductor value for 12V-to-3.3V conversion at 0.6A?

Using the datasheet formula with 30% ripple current (ΔIL = 180mA), fSW = 2.2MHz, and VOUT/VIN = 0.275, the optimal inductance is 3.3µH. Würth 744043003 (3.3µH, 2.15A saturation) or TDK LTF5022T-3R3N2R5 (3.3µH, 2.5A) are validated choices per MPQ2451 application notes.