LT1965EDD-3.3#PBF

Updated: 2026-09-15

Overview

The LT1965EDD-3.3#PBF is a high-performance LDO regulator from Analog Devices, offering a fixed 3.3V output with ultra-low noise (20µVRMS) and high power supply rejection ratio (PSRR). Designed for precision applications, it delivers up to 1.5A of output current with a dropout voltage of 340mV. Its DFN-8 package ensures compact PCB footprint and efficient thermal dissipation. Targeting industrial and automotive systems, this regulator excels in noise-sensitive environments like RF circuits, data converters, and medical devices. Its robust design includes protection features such as current limit and thermal shutdown, enhancing reliability in harsh conditions.

Structure and Working Principle

The LT1965EDD-3.3#PBF integrates a PNP pass transistor, error amplifier, and reference voltage circuit to maintain stable output. The feedback loop adjusts the pass element to compensate for input voltage or load variations, ensuring consistent 3.3V output. Its architecture minimizes ground current, improving efficiency. The DFN-8 package incorporates an exposed pad for thermal management, critical for high-current applications. Internal compensation simplifies external component requirements, typically needing only input/output capacitors for stability.

Key Features

Key advantages include a low dropout voltage (340mV at 1.5A), enabling operation near the output voltage. High PSRR (75dB at 1kHz) filters input noise, while 20µVRMS output noise suits precision analog circuits. Wide input range (2.7V to 20V) accommodates diverse power sources. Protection features like reverse-battery tolerance and thermal shutdown enhance durability. The regulator’s fast transient response (50µs) ensures stability during load steps, critical for digital systems.

Application Areas

Primary applications include powering FPGAs, DSPs, and RF modules in telecom infrastructure. Automotive systems benefit from its AEC-Q100 compliance for infotainment and ADAS. Industrial uses cover PLCs, sensors, and test equipment. Medical devices leverage its low noise for imaging and diagnostic tools. Consumer electronics like high-end audio systems also utilize its clean power delivery.

Maintenance and Precautions

Ensure proper PCB layout with a low-ESR output capacitor (10µF ceramic recommended) near the regulator. The exposed pad must be soldered to a copper plane for heat dissipation. Avoid exceeding junction temperature (125°C) by derating current in high-ambient environments. Input voltage must stay within 2.7V–20V to prevent damage. For reverse-polarity scenarios, external protection diodes are advised.

B2B Procurement Guide

Verify authenticity by purchasing through authorized distributors like Digi-Key or Mouser. Volume discounts apply for orders above 1,000 units. Lead times vary; check Analog Devices’ official stock reports. Evaluate alternatives like LT1764 for lower current needs or adjustable-output variants. Request samples for prototyping, ensuring compatibility with thermal and space constraints.