LDL1117S15R

Product Overview

The STMicroelectronics LDL1117S15R is a positive fixed-output linear voltage regulator IC designed for single-rail 1.5 V power conversion. It provides up to 1.2 A output current from an input voltage up to 18 V, with a maximum dropout of 0.6 V at full load. The device uses a surface-mount SOT-223 package and includes over-current, over-temperature, and under-voltage lockout protection. Its 500 µA quiescent current and PSRR of 87 dB to 65 dB from 120 Hz to 100 kHz support regulated supply functions in compact embedded and board-level power management designs.

Key Features

• Fixed 1.5 V positive output from a single regulator channel
• 1.2 A maximum output current capability
• 0.6 V maximum dropout at 1.2 A
• Input voltage up to 18 V
• 500 µA quiescent current
• PSRR of 87 dB to 65 dB from 120 Hz to 100 kHz
• Over-current, over-temperature, and UVLO protection
• Surface-mount SOT-223 package; package/case TO-261-4 and TO-261AA
• Operating junction temperature range of -40°C to 125°C

Applications

• 1.5 V regulated supply for digital logic subsystems
• Single-rail power conversion for embedded control boards
• Post-regulation from higher voltage rails within the 18 V input limit

Design & Procurement Notes

When selecting this regulator, verify that the available input voltage exceeds the fixed 1.5 V output by enough margin to accommodate the 0.6 V maximum dropout at 1.2 A, while remaining below the 18 V maximum input. The fixed output cannot be adjusted, so the 1.5 V value must match the load requirement. Designers should account for the 500 µA quiescent current, PSRR behavior across 120 Hz to 100 kHz, and thermal limits implied by the -40°C to 125°C junction range. The SOT-223 surface-mount package requires footprint and heat dissipation planning, and the integrated over-current, over-temperature, and UVLO protections should be considered alongside the selected input and output conditions.