L7918CV

Overview

The L7918CV is a three-terminal negative linear voltage regulator from the L7900 series, manufactured by STMicroelectronics. It provides a fixed output voltage of -18 V with a maximum continuous output current of 1.5 A. The device accepts an input voltage range up to -35 V and features internal current limiting, thermal overload protection, and safe area protection. It is housed in a TO-220-3 through-hole package, suitable for applications requiring local on-card regulation or split power supplies.

Feature Summary

• Provides fixed negative voltage regulation for stable power supply rails
• Includes internal circuitry for overcurrent, thermal overload, and safe area protection
• Capable of delivering high output current exceeding 1.5 A when adequate heat sinking is provided

Applications

• Local on-card regulation to eliminate distribution problems associated with single-point regulation
• Split power supply systems utilizing standard positive voltage options
• General-purpose negative voltage regulation in electronic circuits

Procurement Notes

Verify the specific manufacturer part number against official STMicroelectronics documentation to confirm the -18 V fixed output specification. Ensure the procurement channel sources genuine components to guarantee compliance with the stated electrical parameters and RoHS standards. Cross-reference the TO-220-3 package marking for authenticity.

Selection Notes

Select this component when a reliable -18 V negative rail is required for analog or digital logic circuits. It serves as a direct complement to the L78xx positive series for dual-polarity designs. Consider thermal management requirements carefully, as the device can deliver significant current only with proper heat dissipation infrastructure.

Part Context

This component belongs to the L7900 series of three-terminal negative regulators. The series is designed to offer a wide range of fixed output voltages, matching the popular L7800 positive series. This compatibility makes it a standard choice for creating symmetric power supplies in industrial and consumer electronics applications.

Replacement Considerations

Compatible substitutes include other L7918 variants from different manufacturers that meet the same -18 V, 1.5 A specifications and TO-220-3 footprint. Verify pinout compatibility and thermal characteristics before substitution.