Monolithic Power Systems Inc. EVBL4571-QB-00A

Overview

EVBL4571-QB-00A from Monolithic Power Systems is a fully assembled and tested evaluation board for the MP4571 synchronous step-down converter IC, demonstrating 5V/1A output across a 5V–60V input range with integrated 250mΩ HS-FET and 45mΩ LS-FET, 40μA quiescent current, and selectable AAM/FCCM light-load operation in automotive and industrial power systems.

For engineers reviewing the EVBL4571-QB-00A datasheet, EVBL4571-QB-00A pinout, EVBL4571-QB-00A application, or EVBL4571-QB-00A equivalent, this board enables rapid validation of MP4571-based 60V-input DC-DC designs, including cold-crank transient response, load-dump immunity, and configurable switching frequency (450kHz–2.2MHz) with external resistor tuning.

Technical Context

The EVBL4571-QB-00A implements the MP4571's peak-current-mode control architecture with internal compensation, enabling stable regulation under wide VIN transients (e.g., 24V→4V cold crank) and fast load-step recovery (0A→1A). It integrates the MPL-AL6060-150 power inductor and supports dual operating modes: Advanced Asynchronous Mode (AAM) for <40μA IQ at light load and Forced Continuous Conduction Mode (FCCM) for low-noise fixed-frequency operation.

Board-level features include EN-controlled startup/shutdown, PG-indicated output status, SYNCOUT clock output for multi-phase synchronization, and LDO-mode operation during dropout. Input EMI filtering (CIN5 + R8) and damping resistors are optimized for >24V VIN compliance per automotive EMC requirements.

Key Specifications

Availability

EVBL4571-QB-00A is available at Aetrix Electronics and suitable for automotive infotainment power supplies, industrial sensor node regulators, and 60V-input embedded controller auxiliary rails requiring stable component supply, full pre-production validation, and design-in support.

Supply support for EVBL4571-QB-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 expertise in integrated power stages, DC-DC conversion, and automotive-grade reliability.

The EVBL4571-QB-00A belongs to MPS's evaluation board product line, designed specifically to accelerate adoption of their MP4571 60V synchronous buck regulator in harsh-environment applications demanding high input voltage tolerance and transient robustness.

FAQ

What input voltage range does the EVBL4571-QB-00A support?

The board operates from 5V to 60V DC input, validated across automotive cold-crank (down to 4V) and load-dump (up to 60V) conditions. Input filtering components (CIN5, R8) are sized for stability above 24V, and the MP4571 IC maintains regulation throughout this full range with no external adjustments required.

How do I configure the switching frequency on this evaluation board?

Frequency is set by installing an external resistor (RFREQ) between the FREQ pin and GND. The relationship is fSW(kHz) ≈ 30 / RFREQ(MΩ); common values include 66.5kΩ for 1MHz and 76.8kΩ for 400kHz. The board includes test points and footprint for RFREQ placement, with default configuration set to 450kHz.

Can I change the output voltage from 5V to another value?

Yes - VOUT is set by the R4/R5 feedback divider. To adjust, replace R4 (41.2kΩ) and R5 (7.68kΩ) with values calculated using VOUT = 0.8 × (1 + R4/R5). Table 1 in the reference design provides recommended values for 3.3V, 5V, and 12V outputs, all using the same 0.8V internal reference.

What is the purpose of the CCM/SYNCO pin?

The CCM/SYNCO pin serves dual functions: as a mode select input (low = FCCM, high = AAM) and as a 180° out-of-phase clock output when configured as SYNCO. This enables synchronized multi-phase operation or noise reduction in sensitive analog subsystems by phase-shifting switching events.

Does the board include overcurrent or thermal protection?

Yes - the MP4571 IC implements cycle-by-cycle overcurrent protection (OCP) and thermal shutdown (TSD) at 150°C junction temperature. During OCP, the board enters hiccup mode (repeated restart attempts), and TSD disables switching until die temperature falls below 135°C hysteresis - both verified in test reports with 1A sustained load.

Is the EVBL4571-QB-00A RoHS-compliant and lead-free?

Yes - all components on the board, including the MP4571GQB IC (QFN-12), MPL-AL6060-150 inductor, and passive parts, are lead-free, halogen-free, and compliant with the EU RoHS directive. MPS confirms green status on its Quality Assurance portal, and the board carries no exemptions.