Monolithic Power Systems Inc. MPQ4320GDE-AEC1-Z

Overview

MPQ4320GDE-AEC1-Z from Monolithic Power Systems is an AEC-Q100 Grade 1 qualified synchronous step-down converter with integrated 70mΩ high-side and 50mΩ low-side MOSFETs, delivering up to 0.5A output current across a 3.3V–36V input range and surviving 42V automotive load dump transients. It features 1μA shutdown current, configurable 350kHz–1.8MHz switching frequency, and operates from –40°C to +150°C junction temperature - deployed in automotive infotainment power rails.

For engineers reviewing the MPQ4320GDE-AEC1-Z datasheet, MPQ4320GDE-AEC1-Z pinout, MPQ4320GDE-AEC1-Z application, or MPQ4320GDE-AEC1-Z equivalent, key selection criteria include load-dump tolerance, cold-crank support (3.1V min VIN), low-I_Q performance (20μA sleep mode), CISPR25 Class 5 EMI compliance, and QFN-12 (2mm×3mm) wettable flank package compatibility with automotive PCB assembly requirements.

Technical Context

The MPQ4320GDE-AEC1-Z implements peak current mode control with frequency foldback during start-up to prevent inductor current runaway, and supports low-dropout (LOD) mode for automotive cold-crank conditions. Its integrated HS/LS FETs enable high efficiency across light-to-full load via asynchronous modulation (AAM) and dynamic frequency scaling.

It integrates a 0.8V reference error amplifier, open-drain power-good (PG) output with ±5.5% window (94.5–105.5% V_OUT), and hiccup-mode over-current protection. Thermal shutdown triggers at 160–185°C with 20°C hysteresis, and the device uses MeshConnect™ flip-chip packaging for enhanced thermal and EMI performance.

Key Specifications

Pinout & Package

MPQ4320GDE-AEC1-Z is housed in a QFN-12 (2mm × 3mm) package with wettable flanks, optimized for automated optical inspection (AOI) and solder joint reliability in automotive production.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM61480-Q1 and TPS62933-Q1, MPQ4320GDE-AEC1-Z uniquely balances 42V survivability, 0.5A capability, ultra-low I_Q, and wettable-flank manufacturability - making it optimal for cost- and space-constrained automotive subsystems requiring full AEC-Q100 Grade 1 compliance.

Availability

MPQ4320GDE-AEC1-Z is available at Aetrix Electronics and suitable for automotive infotainment, ADAS camera modules, digital instrument clusters, and industrial vehicle telematics requiring stable component supply across extended temperature and qualification lifecycles.

Supply support for MPQ4320GDE-AEC1-Z 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 design centers in the US, China, and Taiwan, and global manufacturing partnerships.

The MPQ4320 product line targets automotive power conversion with AEC-Q100 qualification, emphasizing load-dump resilience, cold-crank operation, and EMI robustness for safety-critical subsystems.

FAQ

What is the minimum input voltage required for startup and sustained operation?

The MPQ4320GDE-AEC1-Z has a VIN UVLO rising threshold of 3.4–3.9V and falling threshold of 2.6–3.1V. Startup requires ≥3.9V, but once running, it sustains regulation down to 3.1V under cold-crank conditions using low-dropout mode - verified across –40°C to +150°C.

Does this part support adjustable output voltage, and what is the feedback reference voltage?

Yes - the MPQ4320GDE-AEC1-Z supports adjustable output via external resistor divider on the FB pin. The internal reference is 0.794–0.806V at 25°C (0.79–0.81V over full temperature range), enabling precise V_OUT setting from 0.8V up to 0.95×VIN.

How is the switching frequency configured, and what resistor values correspond to common frequencies?

Frequency is set by connecting a resistor between FREQ and AGND. Typical values: 86.6kΩ → 415kHz, 34.8kΩ → 1MHz, and 15kΩ → 2.2MHz. The relationship is linear and documented in the Electrical Characteristics table; resistor tolerance directly impacts f_SW accuracy.

Is the PG pin actively driven or open-drain, and what are its voltage thresholds?

The PG pin is open-drain with no internal pull-up. It asserts high when V_OUT is within 94.5–105.5% of nominal, and pulls low when outside 93–107%. A minimum 10kΩ external pull-up to V_OUT or bias rail is required for proper logic-level signaling.

What thermal metrics are specified for the QFN-12 (2mm×3mm) package?

For the MPQ4320GDE-AEC1-Z's QFN-12 (2mm×3mm) package: θ_JA = 60°C/W (JESD51-7, 4-layer board), θ_JC = 7.3°C/W, and Ψ_JT = 1.1°C/W. On MPS's standard evaluation board (EVQ4320-D-00A), measured θ_JA is 35.5°C/W - used for real-world thermal design.

Are there layout recommendations to meet CISPR25 Class 5 emissions?

Yes - the datasheet specifies use of the recommended EMI filter (Figure 16), symmetric VIN pin placement, minimized SW loop area, dedicated PGND plane under the IC, and ferrite beads on input lines. These, combined with built-in FSS, achieve Class 5 compliance without additional shielding.

Does the part support forced PWM mode, or is it limited to AAM operation?

The MPQ4320GDE-AEC1-Z operates exclusively in AAM (asynchronous modulation) mode - it does not support forced PWM. Light-load efficiency is maintained by dynamically reducing switching frequency rather than skipping pulses, minimizing audible noise and output ripple.