LM2576-5.0BU

Voltage Regulators - DC DC Switching Regulators Overview

The LM2576-5.0BU is a monolithic integrated circuit designed as a step-down switching regulator (buck converter) capable of driving a 3A load. It operates with an input voltage range up to 40V and provides a fixed 5.0V output. The device incorporates a fixed-frequency internal oscillator operating at 52kHz, eliminating the need for external frequency compensation. It features TTL shutdown capability for low-power standby modes and includes comprehensive protection mechanisms such as current limiting and thermal shutdown.

Voltage Regulators - DC DC Switching Regulators Feature Summary

• Fixed 5.0V output voltage configuration
• Integrated 52kHz fixed-frequency oscillator
• TTL shutdown pin for power management
• Built-in thermal shutdown and current limit protection

Voltage Regulators - DC DC Switching Regulators Applications

• Simple efficient step-down DC-DC converters
• Pre-regulators for three-terminal linear regulators
• On-card regulation for embedded systems
• Positive-to-negative converter topologies

Voltage Regulators - DC DC Switching Regulators Procurement Notes

Verify the manufacturer origin carefully, as the LM2576 family was originally developed by National Semiconductor and is now distributed by multiple vendors including Microchip Technology and onsemi. Confirm that the specific suffix 'BU' corresponds to the required package type and temperature rating in the official datasheet. Ensure compatibility with existing bill of materials regarding pinout and thermal characteristics before finalizing procurement.

Voltage Regulators - DC DC Switching Regulators Selection Notes

Select this component when a fixed 5V output is required from an input voltage between 4V and 40V. It is suitable for designs prioritizing simplicity and cost-effectiveness over high-frequency efficiency. Consider the 52kHz switching frequency implications for external inductor size compared to modern higher-frequency alternatives. Verify that the TO-220 or similar through-hole package meets the thermal and spatial constraints of the target application.

Voltage Regulators - DC DC Switching Regulators Part Context

This part belongs to the LM2576 series of 3A step-down switching regulators. The series offers various fixed output voltages and adjustable versions. It serves as a direct replacement for older linear regulators like the 78xx series in applications requiring higher efficiency and lower heat dissipation. The technology is mature and widely supported by standard off-the-shelf inductors.

Voltage Regulators - DC DC Switching Regulators Replacement Considerations

Direct substitutes include LM2576-5.0/NOPB from Texas Instruments and LM2576D2TR4-5G from onsemi. These parts share identical electrical specifications and pinouts. When replacing, ensure the alternative source guarantees the same 52kHz oscillation frequency and 3A current handling capability.