Monolithic Power Systems Inc. EVBL4473-L-00A

Overview

EVBL4473-L-00A from Monolithic Power Systems is a fully assembled and tested evaluation board for the MPQ4473GL synchronous step-down converter, delivering 3.3V at up to 3.5A across a 4.5V–36V input range. It integrates an MPS MPL-AL6050-5R6 power inductor and features 500kHz fixed switching frequency, internal 40mΩ/20mΩ MOSFETs, and comprehensive protection including SCP, OCP, OVP, UVP, and thermal shutdown.

For engineers reviewing the EVBL4473-L-00A datasheet, EVBL4473-L-00A pinout, EVBL4473-L-00A application, or EVBL4473-L-00A equivalent, this board enables rapid validation of high-efficiency POL designs in automotive, industrial, and optical communications systems - with direct access to EN, PGOOD, FB, SS, and FREQ signals for configuration and monitoring.

Technical Context

The EVBL4473-L-00A implements the MPQ4473GL IC in a QFN-20 (3mm×4mm) package, configured for fixed 3.3V output using R1=31.6kΩ and R2=10kΩ to set VFB=0.815V. Input filtering uses four ceramic capacitors (C1A–C1D), while output employs dual 22μF X7R 1210 MLCCs plus 0.1μF bypassing for low-noise regulation.

Board-level functionality includes enable control via EN (1.25V turn-on, 0.86V turn-off threshold), power-good signaling on PGOOD, soft-start adjustment via SS pin, and UVLO configuration using R5/R8. The layout follows MPS-recommended thermal and EMI practices with dedicated PGND and AGND planes and optimized SW node routing.

Key Specifications

Availability

EVBL4473-L-00A is available at Aetrix Electronics and suitable for notebook I/O power validation, automotive infotainment subsystem testing, and distributed point-of-load (POL) design requiring stable component supply and fast transient response verification.

Supply support for EVBL4473-L-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 core expertise in DC-DC conversion, motor drivers, and LED drivers.

The EVBL4473-L-00A belongs to MPS's evaluation board product line, designed specifically to accelerate development of high-efficiency, high-voltage buck converters for demanding industrial and automotive applications.

FAQ

What input voltage range does the EVBL4473-L-00A support?

The board operates from 4.5V to 36V DC input, validated across this full range with stable 3.3V output and ≤1% load/line regulation. Testing confirms reliable startup at 4.5V and thermal stability up to 36V with 3.5A load, making it suitable for 12V and 24V automotive and industrial bus applications.

How is output voltage adjusted on this evaluation board?

VOUT is set to 3.3V by default using R1=31.6kΩ and R2=10kΩ, referencing the MPQ4473GL's 0.815V feedback threshold. To change output voltage, replace R1 per Equation (2): R1 = (VOUT − 0.815V) × 12.27kΩ. Compensation components must be recalculated per the MPQ4473 datasheet when modifying VOUT.

Does the board provide power-good signaling?

Yes - the PGOOD pin outputs an open-drain signal active-high when VOUT is within ±8% of regulation (2.9V–3.7V). It drives a 10kΩ pull-up to VOUT and has <10μs response time, enabling safe sequencing in multi-rail systems and fault detection during startup or load transients.

Can the switching frequency be modified?

No - the MPQ4473GL on this board uses internal oscillator set to 500kHz; no external frequency programming pin or resistor option is provided. Frequency remains stable across temperature and load, with measured variation <±3% from 4.5V to 36V input.

What thermal performance can be expected at full load?

At 24V_IN/3.3V_OUT/3.5A, case temperature rise is ≤25°C above ambient (25°C) with no airflow. The board uses 2oz copper layers, thermal vias under U1 and L1, and a low-DCR (14mΩ) MPS inductor to sustain continuous operation without derating in typical lab environments.

Is under-voltage lockout configurable?

Yes - UVLO is implemented using R5 and R8 to scale the internal 0.86V EN threshold. With R5=499kΩ and R8 unpopulated (open), VIN UVLO falls at ~0.86V; adding R8 sets hysteresis and rising/falling thresholds per Equation (1): V_UVLO = 0.86V × (1 + R5/R8).

What is included in the bill of materials for critical power components?

The BOM specifies Murata GRM32ER71H106KA12L (10μF/50V X7R 1210) for input bulk capacitance, Murata GRM32ER71C226KE79 (22μF/16V X7R 1210) for output, and MPS MPL-AL6050-5R6 (5.6μH, 14mΩ DCR, 9.5A ISAT) as the integrated power inductor - all qualified for industrial temperature range and low ESR performance.