MAXREFDES1045: Using MAX17574, wide input range, 5V/3A output synchronous rectification step-down DC-DC converter, two-layer circuit board can reduce costs

MAXREFDES1045 is based on the high-voltage, synchronous rectification buck converter MAX17574, which implements efficient DC-DC step-down conversion and outputs 5V@3A. To reduce costs, this reference design provides a 2-layer PCB layout and complete test data. MAX17574 has a built-in MOSFET and operates in the input voltage range of 4.5V to 60V. The output voltage can be set from 0.9V to 90%VIN. This reference design uses a fixed output of 5V. The device operates over the -40°C to +125°C temperature range, and the feedback voltage regulation accuracy is within ±0.9%. The MAX17574 uses a peak current control architecture. The device can operate in pulse width modulation (PWM), pulse frequency modulation (PFM) or discontinuous conduction (DCM) modes. The programmable soft-start function allows users to reduce input inrush current, and provides an output enable/undervoltage lockout control pin (EN/UVLO), allowing users to turn on the power supply when the input voltage reaches the corresponding requirements. When the output voltage reaches the regulated range, the RESET output is triggered after a certain delay to provide a power-ready indication for the system.

Key Features

• 2-layer board layout reduces power consumption
• Reduces external component count and overall cost
• Reduce DC-DC regulator inventory quantity
• Reduce power consumption
• Ensure reliable operation in harsh industrial environments

This circuit board is not for sale.

Design, build and test

This document introduces the hardware shown in Figure 1 and provides detailed system technical guidance for designing a high-efficiency buck power supply using the MAX17574 step-down DC-DC converter. The power supply has been built and tested, please refer to the documentation for details.

design resources