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LD1117V33

LD1117V33

STMicroelectronics
Linear Voltage Regulator IC Positive Fixed 1 Output 800mA TO-220
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Overview

The STMicroelectronics LD1117V33 is a fixed 3.3V positive linear voltage regulator capable of supplying up to 800mA of output current. It features a low dropout voltage and includes internal current and thermal limiting for protection. Packaged in a TO-220, it is designed for through-hole mounting.

Why Choose This Part

This regulator offers robust protection features including over-current and over-temperature shutdown, enhancing system reliability. Its through-hole TO-220 package allows for easy integration into designs requiring moderate power dissipation with standard heatsinking. The low dropout voltage ensures efficient operation even with small input-to-output voltage differentials.

Applications

General Purpose Power Supplies
Ideal for converting a higher DC voltage (up to 15V) down to a stable 3.3V for various circuits and modules.
Microcontroller Power Rails
Suitable for providing a regulated 3.3V supply to microcontrollers and their associated peripherals.
FPGA/CPLD Power
Can be used to generate the 3.3V core or I/O power supply for FPGAs and CPLDs in embedded designs.
Distributed Power Systems
Useful in systems requiring localized 3.3V regulation from a common higher voltage bus.
Prototyping and Development Boards
A common choice for providing reliable 3.3V power on breadboards and custom prototype PCBs due to its ease of use and common package.

Key Specifications

PSRR 75dB (120Hz)
Output Type Fixed
Mounting Type Through Hole
Package / Case TO-220-3
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 TO-220
Current - Quiescent (Iq) 10 mA
Voltage - Output (Min/Fixed) 3.3V

Getting Started

For getting started, simply connect the input voltage (up to 15V) to the VIN pin, ground to the GND pin, and the regulated 3.3V will be available on the VOUT pin. A small output capacitor (typically 10uF) is recommended for stability. No external compensation networks are required. Datasheet examples provide typical application circuits.

Also Consider

AMS1117-3.3 Advanced Monolithic Systems - Another widely available and pin-compatible 3.3V 800mA linear regulator, often used as a direct replacement.
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