L78M18ABDT

Overview

The L78M18ABDT is a three-terminal positive linear voltage regulator from the STMicroelectronics L78M series. It provides a fixed output voltage of 18 V with a maximum output current capability of 0.5 A. The device is housed in a DPAK surface-mount package and operates within an input voltage range extending up to 35 V. It functions reliably across a temperature range from -40 °C to +125 °C.

Feature Summary

• Integrated internal current limiting and thermal shutdown protection mechanisms ensure robust operation under fault conditions.
• Designed for local or on-card regulation applications, eliminating noise and distribution issues associated with single-point regulation systems.

Applications

• Local or on-card voltage regulation
• General-purpose positive power supplies
• Battery chargers

Procurement Notes

Verify that the specific part number suffix matches the required package type and tape-and-reel configuration. Confirm compliance with RoHS directives and check for any specific automotive or industrial qualification requirements relevant to the target application environment before finalizing procurement.

Selection Notes

Select this component when a fixed 18 V output at 500 mA is required in a compact surface-mount form factor. Ensure the available input voltage headroom accommodates the dropout voltage while staying within the 35 V maximum limit. Consider thermal dissipation requirements based on the load current and ambient operating temperature.

Part Context

This component belongs to the L78M series of three-terminal positive regulators, which are designed as successors to the original L78 series with improved performance characteristics. The series offers various fixed output voltages and is widely used in general electronic equipment requiring stable DC power sources.

Replacement Considerations

Compatible substitutes include other manufacturers' equivalents such as MC78M18CDT or LM340-18MM, provided they match the DPAK package and electrical specifications.