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LD1117AS12TR

LD1117AS12TR

STMicroelectronics
Linear Voltage Regulator IC Positive Fixed 1 Output 1A SOT-223
Active57,161 in stock
Datasheet Digi-Key Mouser Compare Prices

Overview

The LD1117AS12TR is a low-dropout linear regulator capable of providing up to 1A of output current at a fixed 1.2V. It features a maximum input voltage of 15V and incorporates internal protection mechanisms including current limiting and thermal shutdown. The SOT-223 package offers a balance of compact size and thermal performance suitable for modern surface-mount designs.

Why Choose This Part

This regulator offers a very high PSRR of 80dB for clean power delivery and can handle up to 1A with a maximum dropout voltage of 1.3V. It is robustly protected by internal current and thermal limits, ensuring reliability under fault conditions.

Applications

Microcontroller Power Supply
Providing a stable 1.2V core voltage for low-power digital ICs and high-speed microprocessors.
Post-Regulation for Switching Supplies
Utilizing its high PSRR of 80dB at 120Hz to filter ripple from DC-DC converters for sensitive analog circuitry.
Battery Powered Systems
Regulating power in portable devices where a fixed 1.2V rail is required from various battery chemistries.

Key Specifications

PSRR 80dB (120Hz)
Output Type Fixed
Mounting Type Surface Mount
Package / Case TO-261-4, TO-261AA
Current - Output 1A
Protection Features Over Current, Over Temperature
Number of Regulators 1
Output Configuration Positive
Operating Temperature 0degC ~ 125degC
Voltage - Input (Max) 15V
Voltage Dropout (Max) 1.3V @ 1A
Supplier Device Package SOT-223
Current - Quiescent (Iq) 10 mA
Voltage - Output (Min/Fixed) 1.2V

Getting Started

To ensure stability, use a 10uF tantalum capacitor at the output as recommended by the datasheet. Ensure the input voltage remains below the 10V operational limit for optimal performance while accounting for the thermal dissipation of the SOT-223 package when drawing the full 1A current.

Part of 1117 Regulators family » LD1117

LD1117 Family

Comparing specs that differ across variants. The current part is highlighted.

Part Number Package Output V Output I PSRR Output Type Temp Range Stock
LD1117AS12TR (this part) Tape & Reel 4-261 1.2V 1A 120Hz Fixed 0degC ~ 125degC 57,161
LD1117-ADJ 4-261 1.25V — 120Hz Adjustable -40degC ~ 125degC .. 1,570
LD1117DT18TR Tape & Reel 3-252 1.8V 800mA 120Hz Fixed 0degC ~ 125degC 6,765