Monolithic Power Systems Inc. MPQ4321CGDE-5-AEC1-P

Overview

MPQ4321CGDE-5-AEC1-P from Monolithic Power Systems is an AEC-Q100 Grade 1 qualified synchronous step-down converter with integrated 70mΩ/50mΩ MOSFETs, 3.3V–36V input range, 42V load dump tolerance, and fixed 5V output. It delivers up to 1A continuous current with 94.5%–105.5% power-good monitoring and operates from –40°C to +150°C junction temperature-designed for automotive infotainment and ADAS power rails.

For engineers reviewing the MPQ4321CGDE-5-AEC1-P datasheet, MPQ4321CGDE-5-AEC1-P pinout, MPQ4321CGDE-5-AEC1-P application, or MPQ4321CGDE-5-AEC1-P equivalent, key selection criteria include cold-crank support (3.1V min VIN), 1μA shutdown current, CISPR25 Class 5 EMI compliance, configurable switching frequency (350kHz–2.5MHz), and wettable flank QFN-12 (2mm×3mm) package for automated optical inspection.

Technical Context

The MPQ4321CGDE-5-AEC1-P uses peak current-mode control with frequency foldback during start-up to prevent inductor current runaway. Its internal high-side and low-side MOSFETs enable high-efficiency regulation without external switches, while the integrated VCC regulator powers internal circuitry and gate drivers.

It supports forced continuous conduction mode (FCCM), low-dropout (LDO) mode for cold-crank, and open-drain power-good signaling with ±1.5% hysteresis. The FREQ pin allows resistor-based switching frequency setting, and symmetric VIN pinout plus Spread Spectrum modulation reduce EMI emissions per CISPR25 Class 5 requirements.

Key Specifications

Pinout & Package

MPQ4321CGDE-5-AEC1-P is housed in a wettable flank QFN-12 package (2mm × 3mm, 0.5mm pitch), optimized for solder joint inspection and thermal performance (θJA = 60°C/W on 4-layer board).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPQ4321CGDE-5-AEC1-P, the adjustable MPQ4321CGDE-AEC1 offers design flexibility at the cost of component count, while the TPS62130AQRGZTQ1 provides higher current but lacks integrated 42V transient protection and certified EMI performance-making the MPQ4321CGDE-5-AEC1-P optimal for compact, EMI-sensitive automotive 5V rails.

Availability

MPQ4321CGDE-5-AEC1-P is available at Aetrix Electronics and suitable for automotive infotainment systems, ADAS modules, instrument clusters, and industrial HMIs requiring stable component supply with full AEC-Q100 traceability and wettable flank inspection capability.

Supply support for MPQ4321CGDE-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 power management ICs, with core expertise in DC-DC conversion, motor drivers, and LED lighting solutions.

The MPQ4321C product line is designed specifically for automotive power conversion, emphasizing load dump resilience, cold-crank operation, and EMI robustness in compact packages for space-constrained ECUs.

FAQ

What is the purpose of the FREQ pin on MPQ4321CGDE-5-AEC1-P?

The FREQ pin sets the switching frequency via an external resistor to AGND. With RFREQ = 86.6kΩ, fSW = 415kHz; with 15kΩ, fSW = 2.2MHz. This allows designers to optimize for efficiency (lower fSW), size (higher fSW), or EMI (spread-spectrum enabled).

Does MPQ4321CGDE-5-AEC1-P require an external bootstrap capacitor?

Yes. A ceramic capacitor (typically 0.1µF) must be placed between BOOT and SW pins to provide gate drive voltage for the high-side MOSFET. Improper placement or value causes bootstrapping failure and converter shutdown.

How does the power-good (PG) signal behave during startup and fault conditions?

PG goes high after soft-start completes and VOUT reaches 94.5%–105.5% of 5V. It falls low if VOUT exceeds 107% or drops below 93%, with 70µs rising and 60µs falling deglitch timing to reject noise-induced transitions.

Can MPQ4321CGDE-5-AEC1-P operate with input voltage below 3.3V?

No. The absolute minimum operating VIN is 3.3V, and the UVLO falling threshold is 3.1V. Below 3.1V, the device shuts down. For cold-crank scenarios, it maintains regulation down to VIN = 3.1V using LDO mode-but cannot start below 3.3V.

What is the thermal shutdown threshold and hysteresis?

Thermal shutdown activates at TJ = 175°C (typical), with 20°C hysteresis. The device resumes operation only after junction temperature falls below 155°C, ensuring safe cooldown before restart.

Is the MPQ4321CGDE-5-AEC1-P RoHS and halogen-free compliant?

Yes. All MPS parts, including MPQ4321CGDE-5-AEC1-P, are lead-free, halogen-free, and fully compliant with the EU RoHS directive. Green status documentation is available on the MPS Quality Assurance webpage.

How does the wettable flank feature benefit manufacturing yield?

The wettable flank design exposes vertical copper sidewalls on all perimeter pins, enabling automated optical inspection (AOI) of solder fillets-critical for zero-defect requirements in automotive electronics assembly lines.