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L78L05ABUTR

L78L05ABUTR

STMicroelectronics
Linear Voltage Regulator IC Positive Fixed 1 Output 100mA SOT-89-3
Active3,057 in stock
Datasheet Digi-Key Mouser Compare Prices

Overview

The L78L05ABUTR is a three-terminal positive fixed voltage regulator capable of delivering up to 100mA of output current. It is designed to provide local on-card regulation, effectively eliminating the noise and distribution problems associated with single-point regulation by providing a stable 5V rail.

Why Choose This Part

This regulator features internal thermal overload protection and short-circuit current limiting, making it nearly indestructible in most applications. Its SOT-89 package offers a small footprint for space-constrained designs while requiring no external components for basic operation.

Applications

Local Logic Card Regulation
Provides a clean 5V supply for digital ICs and microcontrollers directly on the PCB, reducing susceptibility to noise from long power traces.
Post-Regulation for Switching Supplies
Used after a switching regulator to provide a low-noise 5V output for sensitive analog circuitry.
Current Limiter Circuits
Utilized in simple circuit configurations to limit current for protection or biasing applications.
Battery Powered Equipment
Acts as a compact regulation stage for 5V systems powered by batteries with input voltages up to 30V.

Key Specifications

PSRR 49dB (120Hz)
Output Type Fixed
Mounting Type Surface Mount
Package / Case TO-243AA
Current - Output 100mA
Protection Features Over Current, Over Temperature, Short Circuit
Number of Regulators 1
Output Configuration Positive
Operating Temperature -40degC ~ 125degC
Voltage - Input (Max) 30V
Current - Supply (Max) 6 mA
Supplier Device Package SOT-89-3
Current - Quiescent (Iq) 5.5 mA
Voltage - Output (Min/Fixed) 5V

Getting Started

To implement the L78L05ABUTR, connect the input pin to a DC source between 7V and 30V and the ground pin to your system common. Although it can function without external components, it is best practice to place a 0.33uF ceramic capacitor on the input and a 0.1uF capacitor on the output to improve stability and transient response.

L78L05 Family

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

Part Number Temp Range Stock
L78L05ABUTR (this part) Tape & Reel -40degC ~ 125degC 3,057
L78L05ACUTR Tape & Reel 0degC ~ 125degC 892

Also Consider

UA78L05ACPK TITexas Instruments - Offers similar 100mA 5V regulation in a SOT-89 package with a slightly different operating temperature range.
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