LM2577T-ADJ/LB03

Voltage Regulators - DC DC Switching Regulators Overview

The LM2577T-ADJ/LB03 is a switching voltage regulator IC designed for boost, flyback, and forward converter topologies. It provides a positive adjustable output voltage ranging from 1.23V to 37V with a maximum switch current of 3A. The device operates with an input voltage range of 3.5V to 40V. It utilizes a fixed 52kHz switching frequency to minimize external component count. The unit is housed in a TO-220-5 package with formed leads, suitable for through-hole mounting.

Voltage Regulators - DC DC Switching Regulators Feature Summary

• Integrates a 3.0A NPN power switch with built-in current limiting and thermal protection circuitry.
• Features a fixed 52kHz internal oscillator to reduce the requirement for external passive components.
• Includes undervoltage lockout functionality to ensure stable operation during low input conditions.

Voltage Regulators - DC DC Switching Regulators Applications

• Step-up DC-DC conversion circuits
• Flyback converter designs
• Forward converter architectures

Voltage Regulators - DC DC Switching Regulators Procurement Notes

Verify the manufacturer origin as National Semiconductor or Texas Instruments due to acquisition history. Confirm the specific suffix LB03 corresponds to the required lead form and packaging configuration. Check lifecycle status as obsolete models may require alternative sourcing strategies or last-time buy decisions.

Voltage Regulators - DC DC Switching Regulators Selection Notes

Select this component when a simple step-up solution with high current capability is required. Ensure the input voltage remains within the 3.5V minimum threshold. Verify that the thermal management strategy supports the TO-220-5 package dissipation requirements for the intended load current.

Voltage Regulators - DC DC Switching Regulators Part Context

This part belongs to the LM2577 SIMPLE SWITCHER family, which includes fixed and adjustable output variants. The LM2577 series is known for reducing design complexity in switching power supplies. The 'ADJ' designation indicates an adjustable output voltage controlled by external resistors.

Voltage Regulators - DC DC Switching Regulators Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Consider checking for direct pin-compatible alternatives from Texas Instruments or other manufacturers if availability is critical.