L78L24ACD-TR

Overview

The L78L24ACD-TR is a three-terminal positive linear voltage regulator from the STMicroelectronics L78L series, housed in an 8-SOIC package. It provides a fixed output voltage of 24 V with a maximum output current of 100 mA. The device supports a maximum input voltage of 40 V and operates within a junction temperature range of 0°C to 125°C. Electrical characteristics include a typical quiescent current of 6.5 mA at 25°C and a dropout voltage of 1.7 V. Line regulation is specified at 350 mV (VI = 27 to 38 V) and load regulation at 200 mV (IO = 1 to 100 mA). Supply voltage rejection is typically 37 dB at 120 Hz.

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 to eliminate noise and distribution issues associated with single-point regulation.
• Functions as a direct replacement for Zener diode/resistor combinations while offering lower quiescent current and reduced noise.

Applications

• Local or on-card voltage regulation
• Replacement for Zener diode/resistor networks
• Fixed voltage regulation in electronic circuits

Procurement Notes

Verify that the ordering suffix 'CD' corresponds to the SO-8 package and 'A' indicates ±4% output voltage accuracy. Confirm the '-TR' suffix denotes tape-and-reel packaging. Ensure the component matches the specific pinout configuration for the 8-SOIC footprint before integration into the design.

Selection Notes

Select this component when a fixed 24 V output is required with up to 100 mA capability in a surface-mount format. Consider the SO-8 package for its modified internal frame which decreases thermal resistance compared to standard variants. Verify input voltage requirements do not exceed the 40 V absolute maximum rating for the 24 V output variant.

Part Context

This part belongs to the L78Lxx series of three-terminal positive regulators manufactured by STMicroelectronics. The series includes various fixed output voltages ranging from 3.3 V to 24 V. The L78L24ACD-TR specifically utilizes the SO-8 package, distinguishing it from TO-92 and SOT-89 versions within the same electrical family.

Replacement Considerations

Direct substitutes within the same manufacturer's portfolio include other L78L24 variants such as L78L24ACUTR (SOT-89) or L78L24CD-TR (SO-8 with ±8% accuracy), provided the package and tolerance specifications align with the design requirements.

FAQ

What is the maximum input voltage allowed for the L78L24ACD-TR?

The maximum DC input voltage for the L78L24 variant is 40 V.

Does the L78L24ACD-TR require external components for basic operation?

No external components are required for basic regulation, although capacitors are recommended for stability as per the datasheet test circuits.

What is the output voltage tolerance for the 'A' suffix version?

The 'A' suffix indicates an output voltage tolerance of ±4%.