LM2574-33BWM

Voltage Regulators - DC DC Switching Regulators Overview

The LM2574-3.3BWM is a fixed-output step-down switching voltage regulator manufactured by Micrel, part of the LM2574 family. It provides a fixed 3.3V output with a guaranteed maximum output current of 0.5A. The device operates from an input voltage range up to 40V and utilizes a 52kHz internal oscillator for efficient power conversion. Designed for high efficiency, it incorporates thermal shutdown and current limit protection. The component is housed in an 8-SOIC (0.154", 3.90mm Width) surface-mount package.

Voltage Regulators - DC DC Switching Regulators Feature Summary

• Integrated 52kHz fixed-frequency internal oscillator simplifies external component requirements
• Built-in thermal shutdown and current limit protection ensures operational reliability
• Low power standby mode capability supports energy-efficient system designs

Voltage Regulators - DC DC Switching Regulators Applications

• Simple high-efficiency step-down (buck) regulators
• Efficient pre-regulators for linear regulators
• On-card switching regulators

Voltage Regulators - DC DC Switching Regulators Procurement Notes

Verify the manufacturer origin carefully, as the LM2574 family has been produced by multiple vendors including National Semiconductor, Texas Instruments, and ON Semiconductor. Confirm that the specific suffix corresponds to the SOIC package and 3.3V fixed output. Check RoHS compliance status and lead times, as availability varies significantly across different original equipment manufacturers and distributors.

Voltage Regulators - DC DC Switching Regulators Selection Notes

Select this component when a fixed 3.3V output is required from an input voltage up to 40V with moderate load currents around 500mA. Ensure the application benefits from the 52kHz switching frequency to minimize passive component size. Verify that the SOIC package fits the PCB layout constraints and that the thermal performance meets the operating temperature requirements without excessive heatsinking.

Voltage Regulators - DC DC Switching Regulators Part Context

This part belongs to the LM2574 series of simple switchers, designed to reduce design time for buck converters. The '3.3' indicates the fixed output voltage, while 'BWM' typically denotes the SOIC-8 package variant. The series is known for requiring minimal external components, making it suitable for cost-sensitive and space-constrained power supply designs.

Voltage Regulators - DC DC Switching Regulators Replacement Considerations

Direct substitutes include LM2574-3.3ADJ or LM2574-3.3N depending on package preference. Cross-vendor equivalents such as MIC5205 or similar buck regulators may require schematic adjustments. Verify pin compatibility and thermal characteristics before substitution.