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LF33CDT-TR

LF33CDT-TR

STMicroelectronics
Linear Voltage Regulator IC Positive Fixed 1 Output 500mA DPAK
Active15,421 in stock
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Overview

The LF33CDT-TR is a very low drop voltage regulator designed to provide a fixed 3.3V output at up to 500mA. It features a low quiescent current that remains under control even in dropout mode, making it suitable for battery-powered applications where efficiency is critical. The device includes internal current limiting and thermal shutdown protections to ensure robustness in various operating conditions.

Why Choose This Part

The LF33CDT-TR offers a superior balance of 500mA output capability and low dropout voltage in a compact DPAK package. Its low quiescent current across the full load range and integrated thermal protection make it more efficient and reliable than standard 1117-series regulators.

Applications

Battery-Powered Systems
Utilizes the low 0.7V maximum dropout and 50 uA typical quiescent current to extend battery life in portable electronics.
Post-Regulation
Ideal for cleaning up noise from switching regulators in sensitive analog or digital circuits with a high PSRR of up to 82dB.
Microcontroller Power Supply
Provides a stable 3.3V rail for MCUs and digital logic from input sources up to 16V.
Logic-Controlled Power Management
Employs the TTL-compatible inhibit pin to enable electronic shutdown, reducing supply current to 50uA.

Key Specifications

PSRR 82dB ~ 65dB (120Hz ~ 10kHz)
Output Type Fixed
Mounting Type Surface Mount
Package / Case TO-252-3, DPAK (2 Leads + Tab), SC-63
Current - Output 500mA
Protection Features Over Current, Over Temperature
Number of Regulators 1
Output Configuration Positive
Operating Temperature -40degC ~ 125degC
Voltage - Input (Max) 16V
Voltage Dropout (Max) 0.7V @ 500mA
Current - Supply (Max) 12 mA
Supplier Device Package DPAK
Current - Quiescent (Iq) 1 mA
Voltage - Output (Min/Fixed) 3.3V

Getting Started

When integrating this LDO, ensure a minimum of 2.2 uF capacitance is placed on the output for stability, though 10 uF is often recommended for improved transient response. Connect the inhibit pin to a high logic level to enable the device, or pull it low to enter a low-power shutdown state. The DPAK footprint requires adequate PCB copper pour for thermal dissipation if operating near the 16V maximum input or 500mA maximum load.

LF33 Family

Part NumberDifferenceStock
LF33ABDT-TR Tape & Reel ABDT-TR 21,478

Also Consider

MCP1702 MCHPMicrochip Technology - Better suited for ultra-low power applications where output current requirements are below 250mA.
MIC5219-3.3 MCHPMicrochip Technology - Offers a smaller SOT-23-5 footprint for space-constrained designs needing up to 500mA peak current.