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LD1117S33TR

LD1117S33TR

STMicroelectronics
LDO Voltage Regulators 3.3V 0.8A Positive
20,550 in stock
Datasheet Digi-Key Mouser Compare Prices

Overview

The STMicroelectronics LD1117S33TR is an 800mA fixed 3.3V low-dropout (LDO) voltage regulator. It features internal current limiting and thermal shutdown protection, making it suitable for various general-purpose power regulation tasks. With a typical dropout voltage of 1V and good supply voltage rejection, it provides stable output from input voltages up to 15V.

Why Choose This Part

This LDO offers a balance of output current capability and a fixed 3.3V output, simplifying design by eliminating external feedback resistors. Its internal protection features, including overcurrent and thermal limits, enhance system reliability. The 75 dB typical supply voltage rejection at 120Hz helps to filter input noise.

Applications

Powering Microcontrollers
Provides a stable 3.3V supply for microcontrollers and associated peripheral circuitry in embedded systems.
FPGA and ASIC Core/I/O Power
Suitable for delivering a regulated 3.3V to the I/O rails or core logic of FPGAs, CPLDs, and ASICs where moderate current is required.
Consumer Electronics
Used in portable and consumer devices to regulate voltage for various subsystems, benefiting from its compact SOT-223 package.
Sensor Power Supplies
Offers a regulated and clean 3.3V supply for sensitive analog and digital sensors, helping to maintain measurement accuracy.
General Purpose 3.3V Regulation
A versatile component for any application requiring a reliable 3.3V regulated power rail up to 800mA from a higher voltage source.

Key Specifications

PSRR 75dB (120Hz)
Output Type Fixed
Mounting Type Surface Mount
Package / Case TO-261-4, TO-261AA
Current - Output 800mA
Protection Features Over Current, Over Temperature
Number of Regulators 1
Output Configuration Positive
Operating Temperature 0degC ~ 125degC
Voltage - Input (Max) 15V
Voltage Dropout (Max) 1.2V @ 800mA
Supplier Device Package SOT-223
Current - Quiescent (Iq) 10 mA
Voltage - Output (Min/Fixed) 3.3V

Getting Started

To use the LD1117S33TR, connect its input to an unregulated DC source (up to 15V) and its output to the load. Bypass capacitors on both input and output are recommended to ensure stability, typically 1uF or more. Refer to the datasheet for specific capacitor values and ESR requirements for optimal performance.

Also Consider

AMS1117-3.3 Advanced Monolithic Systems - This is a commonly available pin-compatible alternative with similar specifications, also providing a fixed 3.3V output at 800mA.
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