L78L05ABUTR

Overview

The L78L05ABUTR is a three-terminal positive linear voltage regulator from the STMicroelectronics L78Lxx series, housed in a surface-mount SOT-89 package. It provides a fixed output voltage of 5 V with an accuracy of ±4%. The device supports a maximum output current of 100 mA and operates within an extended junction temperature range of -40 °C to +125 °C. It accepts input voltages up to 30 V for this specific output configuration.

Feature Summary

• Integrates internal current limiting and thermal shutdown mechanisms for robust protection against overload conditions.
• Designed as a fixed-voltage regulator that eliminates the need for external components during standard operation.
• Capable of replacing Zener diode and resistor combinations while offering lower quiescent current and reduced noise.

Applications

• Local or on-card regulation to eliminate noise associated with single-point power distribution.
• Replacement for Zener diode/resistor networks requiring improved stability and lower noise.
• Configuration with external power pass elements to achieve high-current voltage regulation.

Procurement Notes

Verify the component marking and datasheet revision (DS0424 Rev 30) to confirm the 'AB' suffix indicates the ±4% tolerance variant. Ensure the SOT-89 package orientation matches the schematic pinout before integration. Confirm that the application circuit includes appropriate input and output capacitors as specified in the official test circuits to maintain stability.

Selection Notes

Select this part when a fixed 5 V supply is required with ±4% precision and surface-mount assembly is preferred. The SOT-89 package offers a balance between thermal dissipation and board space efficiency compared to through-hole options. Consider the maximum input voltage limit of 30 V relative to the source supply to ensure safe operating margins under all load conditions.

Part Context

This component belongs to the L78Lxx family of three-terminal positive regulators manufactured by STMicroelectronics. The series is characterized by its simplicity, requiring no external feedback components for basic regulation. The L78Lxx line is designed for general-purpose applications where moderate current capability and reliable thermal protection are essential requirements.

Replacement Considerations

The L78L05ACUTR serves as a direct functional substitute within the same package, differing only in output voltage tolerance specifications.