LM1117LDX-1.8

Overview

The LM1117LDX-1.8 is a fixed-output low-dropout linear regulator manufactured by Texas Instruments, providing a stable 1.8 V output with an 800 mA load current capability. It operates within a junction temperature range of 0°C to +125°C and features a maximum dropout voltage of 1.3 V at full load. The device incorporates internal current limiting and thermal shutdown protection, ensuring reliability under overload conditions. It utilizes a Zener-trimmed bandgap reference for high accuracy and requires a minimum 10 µF tantalum capacitor at the output for stability.

Feature Summary

• Space-saving WSON package configuration
• Integrated current limiting and thermal shutdown protection
• Zener-trimmed bandgap reference for precise regulation

Applications

• AC drive power stage modules
• Merchant network and server PSU
• Industrial AC/DC systems
• Ultrasound scanners
• Servo drive control modules

Procurement Notes

Verify that the specific ordering suffix corresponds to the WSON-8 package type, as the LM1117 family spans multiple form factors including SOT-223 and TO-252. Confirm the component grade matches the required operating temperature range of 0°C to +125°C. Ensure the datasheet revision aligns with the manufacturing date code to guarantee compliance with current electrical specifications and pin configurations.

Selection Notes

Select this component when a compact footprint is required alongside standard 800 mA regulation capabilities. The fixed 1.8 V output eliminates the need for external resistors compared to adjustable variants. Consider the thermal resistance characteristics of the WSON package for heat dissipation requirements in dense PCB layouts. Verify input voltage headroom meets the specified dropout requirements across the entire operating temperature range.

Part Context

This device belongs to the LM1117 series of low-dropout linear regulators designed for applications requiring efficient voltage conversion with minimal component count. The series offers both adjustable and fixed output options in various packages. The LM1117LDX-1.8 specifically targets space-constrained designs needing a regulated 1.8 V rail, serving as a legacy alternative to newer TI offerings like the TLV1117 or TLV761.

Replacement Considerations

The TLV1117 is documented as a drop-in alternative. For improved functionality in fixed output SOT-223 configurations, the TLV761 is suggested.