LM2575-3.3WT

Voltage Regulators - DC DC Switching Regulators Overview

The LM2575-3.3WT is a monolithic integrated circuit step-down switching regulator manufactured by Microchip Technology, belonging to the LM2575 series. It provides a fixed 3.3V output with a maximum load current of 1A. The device operates from an input voltage range of 4V to 40V and utilizes a fixed internal oscillator frequency of 52kHz for efficient buck conversion. Designed for surface-mount applications, it features built-in frequency compensation, thermal shutdown, and current limiting protection. The component is housed in a TO-263-5 (D2PAK) package, suitable for industrial and commercial power supply designs requiring high efficiency and minimal external components.

Voltage Regulators - DC DC Switching Regulators Feature Summary

• Integrated fixed-frequency oscillator at 52kHz simplifies design by eliminating external timing components
• Built-in thermal shutdown and current limit protection ensure robust operation under fault conditions
• Requires only four external components to implement a complete step-down switching regulator topology

Voltage Regulators - DC DC Switching Regulators Applications

• Efficient DC-DC step-down converters for general-purpose power supplies
• Pre-regulator stages for linear low-dropout regulators (LDOs)
• Positive-to-negative voltage inversion circuits
• Battery-powered systems requiring high-efficiency voltage regulation

Voltage Regulators - DC DC Switching Regulators Procurement Notes

Verify the manufacturer marking on the component body to confirm Microchip Technology origin, as legacy parts may carry National Semiconductor markings. Ensure the suffix 'WT' corresponds to the correct TO-263-5 tape-and-reel packaging variant rather than tube packaging. Cross-reference the date code against the latest Product Change Notification (PCN) documents to account for any assembly location or material composition updates specified by the manufacturer.

Voltage Regulators - DC DC Switching Regulators Selection Notes

Select this part when a fixed 3.3V output is required with up to 1A load capability from inputs between 4V and 40V. It is appropriate for designs prioritizing simplicity and cost-effectiveness over synchronous rectification efficiencies. Consider the thermal performance of the TO-263-5 package relative to the expected ambient temperature and PCB copper area, as the device lacks active synchronization capabilities found in newer generations.

Voltage Regulators - DC DC Switching Regulators Part Context

The LM2575 series represents a widely adopted family of non-synchronous buck converters known for their reliability and ease of use. The LM2575-3.3WT specifically addresses applications needing a stable 3.3V rail from higher voltage sources. As a legacy product now managed by Microchip Technology following acquisitions, it remains a standard solution for basic switching regulator implementations where high-frequency noise and complex control loops are not primary constraints.

Voltage Regulators - DC DC Switching Regulators Replacement Considerations

LM2575-3.3WU: Direct pin-compatible alternative available in tube packaging instead of tape-and-reel.