LD1117AS12TR

Overview

The LD1117AS12TR is a fixed-output low-dropout linear voltage regulator manufactured by STMicroelectronics. It provides a stable 1.2 V output with a maximum continuous current of 1 A. The device operates within an input voltage range of 2.75 V to 8 V and maintains regulation with a typical dropout voltage of 1 V at full load. It features a quiescent current of 5 mA and offers line regulation of 6 mV/V and load regulation of 10 mV. The unit is housed in a surface-mount SOT-223-3 package, supports operation from 0°C to +125°C, and includes internal thermal and current limiting protections.

Feature Summary

• Fixed 1.2 V output voltage with high accuracy
• Capable of delivering up to 1 A output current
• Low dropout performance for efficient power management
• Integrated thermal overload and short-circuit protection

Applications

• Portable battery-powered equipment requiring stable low-voltage rails
• Embedded systems needing precise logic supply voltages
• Power management circuits in consumer electronics

Procurement Notes

Verify the specific suffix 'S' indicates the SOT-223 package variant when sourcing. Confirm RoHS compliance status through official manufacturer documentation prior to integration. Ensure the ordering code matches the exact 1.2 V fixed output requirement. Cross-reference datasheet revisions to confirm pinout consistency for PCB layout finalization.

Selection Notes

Select this component when a fixed 1.2 V rail is required with high current capability in a compact surface-mount form factor. The SOT-223 package offers superior thermal dissipation compared to smaller alternatives. Consider the 8 V maximum input limit when designing against higher bus voltages. Verify that the 1 A current rating meets the peak load demands of the target application circuit.

Part Context

This part belongs to the LD1117A series of low-dropout regulators designed for efficiency and space optimization. The series utilizes an NPN pass transistor architecture to minimize quiescent current loss. Other variants in the family provide different fixed output voltages such as 1.8 V, 2.5 V, 3.3 V, and 5.0 V, all sharing similar regulatory characteristics and protection features.

Replacement Considerations

LD1117DT12CTR: Alternative LDO providing 1.2 V output in a DPAK package with 800 mA current rating.