Monolithic Power Systems Inc. MPQ4321CGDE-AEC1-P

Overview

MPQ4321CGDE-AEC1-P from Monolithic Power Systems is an AEC-Q100 Grade 1 qualified synchronous step-down converter with integrated 70mΩ/50mΩ HS/LS MOSFETs, 3.3V–36V input range, 42V load dump tolerance, and 1A continuous output current. It operates from –40°C to +150°C junction temperature and supports automotive cold-crank (3.1V min VIN) in infotainment and ADAS power rails.

For engineers reviewing the MPQ4321CGDE-AEC1-P datasheet, MPQ4321CGDE-AEC1-P pinout, MPQ4321CGDE-AEC1-P application, or MPQ4321CGDE-AEC1-P equivalent, key selection criteria include 42V load dump immunity, 1μA shutdown current for battery-sensitive systems, configurable 350kHz–2.5MHz switching frequency, CISPR25 Class 5 EMI compliance, and wettable flank QFN-12 (2mm×3mm) package for automated optical inspection.

Technical Context

The MPQ4321CGDE-AEC1-P uses peak current mode control with frequency foldback during start-up to prevent inductor current runaway. Its integrated MeshConnect™ flip-chip QFN-12 package enables symmetric VIN pinout and low-impedance thermal path, critical for automotive thermal reliability under sustained 1A load.

It implements forced continuous conduction mode (FCCM), low-dropout (LDO) mode for cold-crank, and open-drain power good (PG) with ±1.5% hysteresis referenced to 0.8V FB voltage. Protection includes over-current hiccup mode, thermal shutdown at 175°C, and 42V absolute max VIN per ISO16750.

Key Specifications

Pinout & Package

MPQ4321CGDE-AEC1-P is housed in a wettable flank QFN-12 package (2mm × 3mm, 0.5mm pitch), optimized for solder joint inspection and thermal performance. The package features dual VIN pins and symmetric layout to minimize high-frequency loop area.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck converter applications.

Compared with MPQ4321CGDE-AEC1-P, the fixed-output MPQ4321CGDE-5-AEC1-P reduces design complexity while maintaining identical automotive qualification and EMI performance, whereas TPS54332QPWPRQ1 trades load dump immunity and compactness for higher current capability in less demanding environments.

Availability

MPQ4321CGDE-AEC1-P is available at Aetrix Electronics and suitable for automotive infotainment, ADAS domain controllers, instrument clusters, and industrial 24V power conversion requiring stable component supply across extended temperature and high-reliability production cycles.

Supply support for MPQ4321CGDE-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 power management ICs, with core expertise in DC/DC converters, motor drivers, and LED drivers for automotive, industrial, and consumer markets.

The MPQ4321C product line delivers ultra-compact, AEC-Q100-qualified buck converters targeting space-constrained automotive subsystems requiring high efficiency, low EMI, and robust transient immunity - especially infotainment, clusters, and ADAS power rails.

FAQ

What is the minimum input voltage required to start up the MPQ4321CGDE-AEC1-P?

The device requires a minimum VIN of 3.9V to initiate startup due to its UVLO rising threshold of 3.65V typical. Once running, it sustains regulation down to 3.1V (cold-crank mode), enabled by LDO operation and low dropout characteristics verified across –40°C to +150°C.

Does MPQ4321CGDE-AEC1-P support forced continuous conduction mode (FCCM)?

Yes - FCCM is enabled by default and ensures constant switching frequency under light loads, eliminating audible noise and improving output voltage regulation for sensitive analog circuits like camera ISPs and radar ADCs in ADAS applications.

How is the switching frequency configured on this device?

Frequency is set using an external resistor between the FREQ pin and AGND. For example, 86.6kΩ yields 415kHz, 34.8kΩ yields 1MHz, and 15kΩ yields 2.2MHz. The relationship is monotonic and specified across temperature; no calibration is required.

What thermal performance can be expected in a standard 4-layer PCB layout?

On a JESD51-7 4-layer board (2oz copper), the QFN-12 (2mm×3mm) variant achieves θJA = 60°C/W. At 1A load and 12V input, case temperature rise is ≤12°C above ambient - enabling operation without heatsink in most automotive enclosures up to 85°C ambient.

Is the PG (power good) signal compatible with 3.3V logic systems?

Yes - the open-drain PG output is fully compatible with 3.3V systems when pulled up to 3.3V. Its VOL is ≤0.3V at 1mA sink current, ensuring solid logic-low recognition, and its assertion window (94.5–105.5% of VREF) provides precise regulation monitoring for safety-critical firmware checks.

Can MPQ4321CGDE-AEC1-P be used in non-automotive industrial applications?

Yes - its 42V absolute maximum VIN, –40°C to +150°C operation, and AEC-Q100 qualification make it suitable for industrial 24V systems subject to load dump (e.g., factory automation, railway, or energy infrastructure), where reliability and surge immunity outweigh cost sensitivity.

What is the purpose of the NC pins in the QFN-12 package?

The MPQ4321CGDE-AEC1-P QFN-12 has no NC pins - all 12 pins are functional. Confusion may arise from the QFN-14 variant, which includes two NC pins (pins 2 and 12). This part uses only the 12-pin configuration with no unused terminals.