Monolithic Power Systems Inc. MPQ2451GG-5-AEC1-P

Overview

MPQ2451GG-5-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 5V output, optimized for automotive power rails including infotainment and ADAS domain controllers.

For engineers reviewing the MPQ2451GG-5-AEC1-P datasheet, MPQ2451GG-5-AEC1-P pinout, MPQ2451GG-5-AEC1-P application, or MPQ2451GG-5-AEC1-P equivalent, this device supports high-frequency layout-constrained designs requiring low quiescent current (130µA), internal compensation, ceramic-capacitor stability, and thermal shutdown in QFN-6L packaging.

Technical Context

The MPQ2451GG-5-AEC1-P implements current-mode control with a fixed 2.2MHz oscillator and internal soft-start, enabling fast transient response and controlled startup without external components. Its pulse-skipping mode reduces gate-driving and switching losses under light load, while frequency fold-back prevents inductor current runaway during start-up.

It integrates a bootstrap regulator that charges the BST capacitor from VIN–SW, with UVLO protection on the floating driver (rising threshold ~2.4V). The error amplifier uses an internal reference (VREF ≈ 0.8V) and COMP node feedback to regulate output via peak-current sensing-no external current-sense resistor required.

Key Specifications

Pinout & Package

MPQ2451GG-5-AEC1-P is housed in a thermally enhanced 2mm × 2mm QFN-6L package with exposed thermal pad (pin 1 = SW, pin 2 = EN, pin 3 = OUT, pin 4 = GND, pin 5 = VIN, pin 6 = BST), supporting reflow-compatible assembly and PCB-level thermal management via ≥6 thermal vias under the pad.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS62130A-Q1 and LM61480-Q1, MPQ2451GG-5-AEC1-P delivers precise 5V regulation in smallest footprint (4mm²), lowest quiescent current, and full AEC-Q100 Grade 1 validation - making it the most efficient fit for space- and power-constrained automotive subsystems below 0.7A.

Availability

MPQ2451GG-5-AEC1-P is available at Aetrix Electronics and suitable for automotive infotainment, ADAS camera modules, body control units, and telematics control units requiring stable component supply with guaranteed long-term automotive lifecycle support.

Supply support for MPQ2451GG-5-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 series belongs to MPS's automotive-qualified DC/DC converter product line, engineered specifically for harsh-environment vehicle subsystems requiring AEC-Q100 compliance, wide input range, and minimal external components.

FAQ

What is the maximum allowable input voltage for MPQ2451GG-5-AEC1-P, and what protection applies beyond that?

The absolute maximum input voltage is +40V. Exceeding this risks permanent damage to the internal high-side MOSFET and control circuitry. The device incorporates under-voltage lockout (UVLO) with rising threshold at ~2.9V and hysteresis of 0.4V, but no overvoltage protection circuitry - external TVS or clamp diodes are required for ISO 7637-2 pulse 5a (75V/100ms) compliance.

Can MPQ2451GG-5-AEC1-P operate with a 3.3V input, and what is the minimum duty cycle limitation?

Yes, it operates down to 3.3V input, but minimum on-time (80ns) limits achievable duty cycle. At 3.3V input and 5V output, theoretical duty cycle is 151%, which is physically impossible - thus the device cannot regulate 5V from 3.3V. Minimum functional input is ~6V for 5V output, per datasheet's "6V < VIN < 36V" condition for V_OUT specification.

Does MPQ2451GG-5-AEC1-P require an external bootstrap diode, and when is it recommended?

No external bootstrap diode is required for standard operation. It is recommended only when VIN ≤ 6V, duty cycle exceeds 65%, or a system 5V rail is available - in those cases, connecting a BAT54 or IN4148 from 5V to BST improves gate-drive margin and efficiency by supplementing bootstrap capacitor charging during high-duty cycles.

How does the internal current limit behave across temperature, and is it adjustable?

The current limit is internally set and temperature-compensated: 0.75A typical at 25°C, 0.65A minimum from −40°C to +125°C. It is not adjustable - no external resistor or pin-strapping modifies the threshold. This fixed, cycle-by-cycle limiting eliminates need for external sense resistors while ensuring consistent short-circuit protection across automotive temperature ranges.

What thermal performance can be expected in the QFN-6L package at 0.6A load, and how many thermal vias are recommended?

With proper PCB layout (2oz copper, 6×15-mil thermal vias under exposed pad), junction-to-ambient thermal resistance is 80°C/W. At 0.6A and 12V input, power dissipation is ~0.3W, resulting in ~24°C rise above ambient - well within 125°C max junction limit. Layout guidelines specify ≥6 vias on 40-mil pitch, filled during plating to avoid solder wicking.

Is the MPQ2451GG-5-AEC1-P pin-compatible with the SOT23-6L variant MPQ2451GT-5-AEC1?

No - pin assignments differ between QFN-6L and SOT23-6L packages. In QFN-6L: Pin 1=SW, Pin 2=EN, Pin 3=OUT, Pin 4=GND, Pin 5=VIN, Pin 6=BST. In SOT23-6L: Pin 1=BST, Pin 2=GND, Pin 3=OUT, Pin 4=EN, Pin 5=VIN, Pin 6=SW. Direct replacement requires PCB redesign; functional equivalence exists, but mechanical layout is not interchangeable.