Monolithic Power Systems Inc. EVQ4323M-G-00A

Overview

EVQ4323M-G-00A from Monolithic Power Systems is a fully assembled and tested evaluation board for the MPQ4323M - a 36V-input, 3A-output, AEC-Q100 Grade 1 synchronous buck converter with 1μA shutdown quiescent current, 350kHz–2.5MHz configurable switching frequency, and integrated high-side/low-side MOSFETs in a QFN-12L (3.5mm×3.5mm) package. It demonstrates automotive-grade power conversion for 5V/3A rail generation under cold-crank and load-dump conditions.

For engineers reviewing the EVQ4323M-G-00A datasheet, EVQ4323M-G-00A pinout, EVQ4323M-G-00A application, or EVQ4323M-G-00A equivalent, this board enables rapid validation of MPQ4323M's efficiency (95.6% peak), thermal performance (≤59.5°C at 3A, no airflow), CISPR25 Class 5 EMI compliance, low-dropout operation down to 3.3V input, and power-good signaling across automotive voltage transients.

Technical Context

The EVQ4323M-G-00A implements the MPQ4323M IC in a fixed 5V output configuration using a 100kΩ/19.1kΩ feedback divider, with 2.2µH output inductor (XEL4030-222MEB) and 44µF total output capacitance (2×22µF/25V ceramic). Input filtering includes 4.7µF ×2 + 0.1µF ceramic + 22µF polymer capacitors and a 3A magnetic bead (742792063) for EMI suppression.

It supports full functional validation of key MPQ4323M features: frequency foldback during start-up, thermal shutdown, open-drain power-good (PG) monitoring with ±5.5% window, enable control (EN threshold: 0.85V/1.02V), and high-duty-cycle LDO mode for automotive cold-crank (VIN as low as 3.3V).

Key Specifications

Availability

EVQ4323M-G-00A is available at Aetrix Electronics and suitable for automotive ADAS domain controllers, infotainment head units, and body electronics requiring stable component supply, pre-validated power architecture, and AEC-Q100-compliant reference designs.

Supply support for EVQ4323M-G-00A 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 expertise in DC/DC converters, LED drivers, and motor drivers for automotive, industrial, and consumer applications.

The MPQ4323M product line delivers AEC-Q100-qualified synchronous buck regulators optimized for automotive front-end power conversion - emphasizing ultra-low IQ, wide VIN range, robust transient response, and integrated EMI mitigation.

FAQ

What input voltage range is supported on the EVQ4323M-G-00A board?

The board supports 3.3V to 36V input, validated for automotive cold-crank (3.3V) and 42V load dump events. Input filtering includes 22µF polymer + 4.7µF ×2 + 0.1µF ceramics and a 3A magnetic bead to maintain stability and meet CISPR25 Class 5 requirements.

How is output voltage adjusted on this evaluation board?

VOUT is set by an external resistor divider (R5 = 100kΩ, R6 = 19.1kΩ) connected to the FB pin, yielding a fixed 5V output. To change VOUT, replace R6 per Equation (1): R6 = R5 × (VOUT − 0.8V) / 0.8V. The board includes test points for FB, VOUT, and PG signals.

Does the board include EMI filtering components?

Yes - it integrates a 3A magnetic bead (Wurth 742792063) at the input, plus 4.7µF ×2 + 0.1µF + 22µF polymer capacitors. This passive filter stack achieves CISPR25 Class 5 peak/average conducted and radiated emissions compliance without additional shielding or ferrites.

What thermal performance can be expected at full 3A load?

At 12V_IN/5V_OUT, 3A, and no forced airflow, the board's case temperature rises 59.5°C above ambient (measured per EVB test report). This validates the QFN-12L thermal pad layout and copper pour design for automotive under-hood environments.

Can the MPQ4323M's switching frequency be modified on this board?

Yes - the FREQ pin accepts an external resistor to GND. Default is 2.2MHz (R_FREQ ≈ 13.3kΩ); values from 10kΩ to 100kΩ adjust f_SW from 2.5MHz down to 350kHz, enabling optimization for efficiency, size, or EMI.

Is power-good (PG) functionality accessible for system monitoring?

Yes - the open-drain PG signal is routed to a test point and labeled "PG" on the silkscreen. It asserts high when VOUT is within 94.5%–105.5% of nominal, supporting microcontroller reset sequencing and fault detection in automotive systems.