LDL1117S50R

Overview

The LDL1117S50R is a fixed-output linear voltage regulator from the LDL1117 series, manufactured by STMicroelectronics. It provides a guaranteed output current of 1.2 A with a fixed output voltage of 5.0 V. The device operates within an input voltage range of 2.5 V to 18 V and features a typical dropout voltage of 350 mV at full load. It incorporates high power supply rejection ratio (PSRR) performance, reaching 87 dB at 120 Hz. Integrated protections include internal thermal shutdown, current limiting, and safe operating area (SOA) protection. The component is housed in a surface-mount SOT-223 package with four pins.

Feature Summary

• Provides stable 5.0 V regulation with up to 1.2 A continuous output current capability
• Features high power supply rejection ratio for effective noise filtering in sensitive circuits
• Includes comprehensive internal protection mechanisms against thermal overload, excessive current, and unsafe operating conditions

Applications

• Direct regulation in switch-mode power supply (SMPS) architectures
• Secondary linear regulation stages in DC-DC converter designs
• Power management for low-dropout requirements in embedded systems

Procurement Notes

Verify the specific suffix 'R' against the official STMicroelectronics datasheet to confirm tape-and-reel packaging configuration. Ensure the part number matches the exact fixed 5.0 V output variant. Cross-reference the SOT-223 package dimensions and pinout with the manufacturer's mechanical drawing to prevent assembly errors during PCB design and manufacturing.

Selection Notes

Select this component when a fixed 5.0 V rail is required with moderate current demands up to 1.2 A. It is suitable for applications needing high PSRR to suppress ripple from upstream switching regulators. Consider the thermal dissipation capabilities inherent to the SOT-223 package relative to the expected ambient temperature and input-output voltage differential to ensure operation within the specified junction temperature limits.

Part Context

This regulator belongs to the LDL1117 family of high-performance, low-dropout linear voltage regulators designed for general-purpose power management. The series offers various fixed output voltages and supports up to 1.2 A output current. These devices are engineered for efficiency and reliability in compact surface-mount applications, providing robust protection features essential for modern electronic systems.

Replacement Considerations

Consult the official STMicroelectronics replacement guide or equivalent manufacturer documentation for verified cross-reference part numbers. Do not assume functional compatibility based solely on pinout similarity; verify electrical parameters and package specifications.