Monolithic Power Systems Inc. EV4423A-Q-00A

Overview

EV4423A-Q-00A from Monolithic Power Systems is an evaluation board for the MPQ4423AGQ-AEC1 synchronous step-down converter, supporting 4–36V input and delivering regulated 3.3V/3A output in automotive-grade QFN-8 (3mm×3mm) package. It integrates low-R_DS(ON) MOSFETs (85mΩ/55mΩ), operates at 410kHz default switching frequency, and features Power Good signaling, thermal shutdown, and hiccup-mode over-current protection.

For engineers reviewing the EV4423A-Q-00A datasheet, EV4423A-Q-00A pinout, EV4423A-Q-00A application, or EV4423A-Q-00A equivalent, this board enables rapid validation of MPQ4423AGQ-AEC1 performance in cold-crank automotive systems, industrial power rails, and distributed DC-DC conversion where forced CCM, external clock synchronization (200kHz–2.2MHz), and 0.792V feedback reference are critical design requirements.

Technical Context

The EV4423A-Q-00A implements a current-mode controlled buck topology using the MPQ4423AGQ-AEC1 IC, which integrates high- and low-side MOSFETs with 85mΩ and 55mΩ R_DS(ON), respectively. Its 410kHz fixed-frequency operation supports forced continuous conduction mode (CCM) and external clock synchronization via the EN/SYNC pin.

Feedback is set to 3.3V using a precision 0.792V internal reference with resistor divider (R7=41.2kΩ, R8=13kΩ). The board includes full protection: over-current protection with hiccup recovery, thermal shutdown, and Power Good (PG) assertion at ±5% V_OUT tolerance.

Key Specifications

Availability

EV4423A-Q-00A is available at Aetrix Electronics and suitable for automotive infotainment power supplies, industrial PLC I/O modules, and distributed telecom power rails requiring stable component supply, pre-validated layout, and AEC-Q100-compliant reference design support.

Supply support for EV4423A-Q-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 analog semiconductor company specializing in high-performance power management ICs, with core expertise in DC-DC conversion, motor drivers, and LED lighting controllers.

The MPQ4423A product line delivers AEC-Q100-qualified synchronous buck converters for automotive and harsh-environment applications, emphasizing cold-crank robustness, high efficiency across load range, and integrated protection.

FAQ

What input voltage range does the EV4423A-Q-00A support?

The board supports 4V to 36V DC input, enabling operation during automotive cold-crank events (down to 4V) and compatibility with 12V/24V vehicle electrical systems. Input filtering uses a 22μF electrolytic capacitor (CIN5) and multiple ceramic bypass caps (CIN1, CIN2, CIN4) per the MPQ4423AGQ-AEC1 recommended layout.

How is output voltage set on this evaluation board?

V_OUT is fixed at 3.3V using resistor divider R7 (41.2kΩ) and R8 (13kΩ) connected to the FB pin, referencing the IC's internal 0.792V feedback threshold. The calculation follows V_OUT = 0.792V × (1 + R7/R8); no solder jumpers or trim pots are required for this configuration.

Can the EV4423A-Q-00A be synchronized to an external clock?

Yes - the EN/SYNC pin accepts a 200kHz–2.2MHz external clock signal. When driven, the internal oscillator locks to the rising edge of the external clock, enabling phase-aligned multi-rail operation. Pulse width must remain below 1.7μs to ensure reliable synchronization.

What protection functions are implemented on this board?

The board inherits all protections from the MPQ4423AGQ-AEC1: over-current protection with automatic hiccup recovery, thermal shutdown with hysteresis, and Power Good (PG) monitoring. No additional discrete protection circuitry is added - functionality is fully integrated into the IC and validated per Rev.1.0 test report.

Is the EV4423A-Q-00A fully assembled and tested?

Yes - the board ships fully assembled with all components populated, including dual 10μH shielded inductors (XAL5050-103ME), 22μF output ceramics (GRM32ER71C226KE79), and AEC-Q200-rated input capacitors. Each unit undergoes functional testing at room temperature per the test conditions documented in the Rev.1.0 user guide.

What is the physical size and connector interface of the board?

The board measures 2.5" × 2.5" × 0.2" (6.35cm × 6.35cm × 0.5cm) with five 2.0mm-pitch golden-pin headers (VIN, VEMI, GND, VOUT, GND) and five 1.0mm-pitch golden-pin headers (EN/SYNC, GND, PG, GND, CLK_OUT), enabling direct connection to lab power supplies and logic analyzers without adapters.