L78L08ACD

Overview

The L78L08ACD is a three-terminal positive linear voltage regulator from the STMicroelectronics L78L series, designed for fixed voltage regulation. It provides an output voltage of 8 V with a maximum output current of 100 mA. The device features internal current limiting and thermal shutdown protection, ensuring robust operation under overload conditions. It operates within a junction temperature range of 0 to 125 °C and requires no external components for basic functionality. The part is available in SO-8 surface-mount packaging.

Feature Summary

• Integrated thermal overload protection prevents damage during excessive heat generation.
• Built-in short-circuit protection safeguards the device against output faults.
• Internal current limiting ensures safe operation without external sensing components.

Applications

• Local or on-card voltage regulation
• Elimination of noise associated with single-point regulation
• Replacement for Zener diode and resistor combinations

Procurement Notes

Verify the specific package variant (SO-8) and tolerance code (A for ±4%) when sourcing. Confirm that the ordering suffix matches the required tape-and-reel or cut-tape configuration. Ensure compatibility with the intended PCB footprint and thermal management strategy, as power dissipation depends on input-output differential and load current.

Selection Notes

Select this component for applications requiring a stable 8 V supply with currents up to 100 mA. The AC designation indicates a tighter voltage tolerance compared to the C series. Consider the SO-8 package for surface-mount assembly needs. Evaluate thermal resistance requirements based on the expected voltage drop and ambient operating conditions to ensure reliable performance within the specified temperature range.

Part Context

This component belongs to the L78L family of low-current positive voltage regulators. Unlike the higher-power L7800 series, the L78L series is optimized for lower current applications, typically delivering up to 100 mA. The family offers various fixed output voltages and packaging options, including through-hole and surface-mount configurations, catering to diverse space-constrained electronic designs.

Replacement Considerations

Direct pin-compatible substitutes may include other manufacturers' L78L08 variants. Verify electrical characteristics such as line/load regulation and quiescent current to ensure functional equivalence. Check package dimensions and thermal properties if replacing with a different brand's SO-8 version.

FAQ

What is the voltage tolerance for the L78L08ACD?

The 'AC' suffix indicates a ±4% output voltage tolerance at 25 °C, resulting in an output range of 7.68 V to 8.32 V.

Does the L78L08ACD require external capacitors?

No external components are strictly required for basic operation, but datasheet test circuits typically recommend input and output capacitors for stability.