LM2577T-15/LB03

Voltage Regulators - DC DC Switching Regulators Overview

The LM2577T-15/LB03 is a SIMPLE SWITCHER step-up voltage regulator IC from Texas Instruments, housed in a TO-220-5 Formed Lead package. It provides a fixed 15V output with a maximum switch current of 3A. The device operates within an input voltage range of 3.5V to 40V and supports boost, flyback, and forward converter topologies. It features a standard switching frequency of 52kHz and functions as a positive output regulator. The component is rated for a junction temperature range of -40°C to 125°C.

Voltage Regulators - DC DC Switching Regulators Feature Summary

• Integrated monolithic power switch eliminates the need for external driver components
• Fixed internal oscillator ensures stable switching frequency without external timing adjustments
• Built-in thermal shutdown circuitry protects against overheating during fault conditions
• Standardized pinout allows for direct replacement in existing boost converter designs

Voltage Regulators - DC DC Switching Regulators Applications

• Industrial power supply systems requiring isolated or non-isolated step-up conversion
• Battery-powered equipment needing voltage elevation from lower cell voltages
• Embedded systems utilizing flyback or forward converter architectures
• General-purpose DC-DC boosting applications in automotive environments

Voltage Regulators - DC DC Switching Regulators Procurement Notes

Verify that the specific suffix LB03 matches the required tape-and-reel packaging configuration, as other suffixes may indicate tube packaging. Confirm that the fixed 15V output aligns precisely with the target system requirements, as adjustable variants exist within the same family. Ensure the TO-220-5 through-hole form factor fits the mechanical constraints of the final assembly. Check for any recent lifecycle notices regarding end-of-life status or recommended new replacements from the manufacturer.

Voltage Regulators - DC DC Switching Regulators Selection Notes

Select this component when a fixed 15V output is strictly required rather than an adjustable voltage rail. The 3A switch current capability suits moderate power loads where efficiency and simplicity are prioritized over ultra-low quiescent current. Consider the 52kHz switching frequency for balancing component size and electromagnetic interference. This part is suitable for designs tolerant of through-hole mounting and does not require synchronous rectification complexity.

Voltage Regulators - DC DC Switching Regulators Part Context

This regulator belongs to the SIMPLE SWITCHER family, designed for ease of use with minimal external components. It shares architectural similarities with the LM2576 buck regulator but is configured specifically for step-up operations. The TO-220-5 package provides robust thermal dissipation capabilities compared to smaller surface-mount options, making it suitable for higher power density applications within the 3A limit.

Voltage Regulators - DC DC Switching Regulators Replacement Considerations

LM2577T-ADJ/LF03 is listed as a parameter-equivalent substitute, though it offers an adjustable output rather than a fixed 15V rail. Verify compatibility if the application requires voltage flexibility. No other direct fixed-voltage equivalents are confirmed in the provided documentation.