L78L09ACD13TR

Overview

The L78L09ACD13TR is a three-terminal positive linear voltage regulator from the STMicroelectronics L78L series, housed in an 8-SOIC surface-mount package. It provides a fixed output voltage of 9 V with a maximum output current of 100 mA and operates within a junction temperature range of 0 °C to 125 °C. The device features internal thermal overload protection and short-circuit protection, eliminating the need for external components. It accepts a maximum DC input voltage of 30 V and maintains line regulation of 225 mV and load regulation of 80 mV under specified conditions.

Feature Summary

• Integrated thermal overload and short-circuit protection mechanisms ensure robust operation without external protective circuitry.
• Designed as a fixed-voltage regulator suitable for local or on-card regulation to eliminate noise associated with single-point distribution.
• Capable of replacing Zener diode and resistor combinations while offering lower quiescent current and reduced output noise.

Applications

• Local or on-card voltage regulation
• Replacement for Zener diode/resistor networks
• Building blocks for high-current regulators using power pass elements

Procurement Notes

Verify that the component matches the specific L78L09ACD13TR designation, including the 'A' accuracy grade and SO-8 package type. Confirm compliance with RoHS directives and check for any recent Product Change Notifications (PCN) regarding packaging or manufacturing site updates before finalizing procurement orders.

Selection Notes

Select this component when a fixed 9 V output is required with up to 100 mA load capability in a compact surface-mount form factor. Ensure the input voltage remains below the 30 V absolute maximum rating and verify that the PCB copper area supports adequate heat dissipation given the SO-8 package thermal characteristics.

Part Context

This part belongs to the L78Lxx family of low-power three-terminal positive regulators manufactured by STMicroelectronics. The series includes various fixed output voltages and packages such as TO-92, SOT-89, and SO-8. The 'AC' suffix indicates a ±4% output voltage tolerance, distinguishing it from the standard 'C' variant which offers ±8% tolerance.

Replacement Considerations

Direct substitutes include the L78L09ABD13TR, which shares identical electrical specifications but extends the operating temperature range down to -40 °C. Other compatible options within the same family include the L78L09CD13TR, though it possesses a wider ±8% voltage tolerance compared to the ±4% accuracy of the AC variant.