Monolithic Power Systems Inc. MPQ2451DG-AEC1-LF-P

Overview

MPQ2451DG-AEC1-LF-P from Monolithic Power Systems is an AEC-Q100 Grade 1 qualified, non-synchronous step-down DC/DC converter with integrated 500mΩ high-side MOSFET, delivering up to 0.6A at adjustable output (0.8V–0.9·VIN) or fixed 3.3V/5V, operating from 3.3V–36V input and featuring 2MHz fixed switching frequency, 130µA quiescent current, and internal soft-start - used in automotive body control modules for stable 5V rail generation from battery.

For engineers reviewing the MPQ2451DG-AEC1-LF-P datasheet, MPQ2451DG-AEC1-LF-P pinout, MPQ2451DG-AEC1-LF-P application, or MPQ2451DG-AEC1-LF-P equivalent, key selection criteria include AEC-Q100 Grade 1 qualification, 36V max input tolerance, QFN-6L thermal performance (θJA = 80°C/W), precision current limit without external sense resistor, and compatibility with ceramic output capacitors.

Technical Context

The MPQ2451DG-AEC1-LF-P implements current-mode PWM control with internal compensation and a dedicated 2MHz oscillator, enabling fast transient response and stable regulation across wide load and input ranges. Its pulse-skipping mode reduces gate-driving and switching losses under light loads, while frequency fold-back prevents inductor current runaway during startup.

It integrates a bootstrap regulator for high-side driver biasing, features UVLO with 2.9V rising threshold and 0.4V hysteresis, and includes thermal shutdown at 150°C with automatic recovery. The error amplifier uses an internal 0.794V reference and supports external feedback divider configuration for output voltage setting.

Key Specifications

Pinout & Package

MPQ2451DG-AEC1-LF-P is housed in a thermally enhanced, RoHS-compliant QFN-6L package (2mm × 2mm × 0.75mm, 0.5mm pitch) with exposed thermal pad for PCB heat sinking - optimized for automotive PCB layouts requiring high power density and thermal reliability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS54331DR and LMR36506RNXR, MPQ2451DG-AEC1-LF-P offers the optimal balance of AEC-Q100 Grade 1 compliance, 36V input tolerance, QFN-6L compactness, and 130µA quiescent current - making it uniquely suited for space-constrained, battery-sensitive automotive modules where full 65V rating is unnecessary.

Availability

MPQ2451DG-AEC1-LF-P is available at Aetrix Electronics and suitable for automotive body electronics, ADAS camera modules, and telematics control units requiring stable component supply with guaranteed long-term automotive lifecycle support.

Supply support for MPQ2451DG-AEC1-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 design centers in the US, China, and Taiwan, and global manufacturing partnerships.

The MPQ2451 belongs to MPS's automotive-qualified DC/DC converter product line, engineered specifically for harsh-environment automotive power conversion - emphasizing AEC-Q100 reliability, wide input range, low quiescent current, and minimal external component count.

FAQ

What is the maximum allowable input voltage for MPQ2451DG-AEC1-LF-P?

The absolute maximum input voltage is +40V, but the recommended operating range is 3.3V to 36V per datasheet specifications. Operation above 36V risks exceeding safe junction temperature limits even with proper heatsinking, and sustained exposure beyond 40V may cause permanent damage to the internal MOSFET or control circuitry.

Can MPQ2451DG-AEC1-LF-P be used with a 3.3V fixed output configuration?

Yes - the MPQ2451DG-AEC1-LF-P variant supports fixed 3.3V output (part number MPQ2451GG-33-AEC1). For the MPQ2451DG-AEC1-LF-P, which is the QFN-6L package without pre-programmed output, use an external feedback divider (e.g., R1 = 124kΩ, R2 = 40.2kΩ) to set VOUT = 3.3V with ±2% accuracy over temperature.

Does MPQ2451DG-AEC1-LF-P require an external bootstrap diode?

No - the device integrates a bootstrap regulator that charges the BST capacitor from VIN during low-side conduction. An external diode is optional and only recommended for high-duty-cycle applications (VOUT/VIN > 65%) or when VIN ≤ 5V and a stable 5V rail is available; typical use cases do not require it.

How does the pulse-skipping mode improve light-load efficiency?

Pulse-skipping reduces switching and gate-driving losses by disabling PWM cycles when the COMP voltage falls below the internal sleep threshold. This lowers quiescent current to ~130µA and maintains >80% efficiency down to 1mA load - critical for automotive modules in sleep mode where battery drain must be minimized.

What thermal derating applies to the QFN-6L package at 85°C ambient?

With θJA = 80°C/W, the maximum allowable power dissipation at 85°C ambient is PD(MAX) = (125°C − 85°C)/80°C/W = 0.5W. At 0.6A output and 12V input, typical power loss is ~0.25W, leaving 0.25W margin - sufficient for most automotive applications without forced airflow or additional copper pour.

Is the FB pin compatible with remote sensing configurations?

No - the FB pin is designed for local feedback only. It lacks dedicated remote-sense inputs (e.g., separate VOS+ and VOS− pins), and its internal error amplifier has fixed gain and compensation. For remote sensing, external op-amp-based compensation or a different regulator (e.g., MPQ4470) is required.

What is the minimum output capacitance required for stability?

The device is stable with ≥10µF ceramic output capacitance (X5R/X7R, 6.3V rating). Lower values (e.g., 4.7µF) may cause phase-margin reduction and audible switching noise under transient load; 10µF ensures ≥45° phase margin and robust performance across –40°C to +125°C.