LT1681

PRODUCTION

Dual Transistor Synchronous Forward Controller

Viewing:

Overview

  • High Voltage: Operation Up to 72V
  • Synchronizable Operating Frequency and Output Switch Phase for Multiple Controller Systems
  • Fixed Frequency Operation to 350kHz
  • Adaptive and Adjustable Blanking
  • Synchronous Rectifier Driver
  • Local 1% Voltage Reference
  • Undervoltage Lockout Protection with Hysteresis
  • Input Overvoltage Protection
  • Programmable Start Inhibit
  • Transformer Primary Saturation Protection
  • Optocoupler Feedback Support
  • Soft-Start Control

The LT1681 controller simplifies the design of high power synchronous dual transistor forward DC/DC converters. The part employs fixed frequency current mode control and supports both isolated and nonisolated topologies. The IC drives external N-channel power MOSFETs and operates with input voltages up to 72V.

The LT1681’s operating frequency is programmable and can be synchronized up to 350kHz. Switch phase is also controlled during synchronized operation to accommodate multiple converter systems. Internal logic guarantees 50% maximum duty cycle operation to prevent transformer saturation.

The LT1681 incorporates a soft-start feature that provides a controlled increase in supplied current during start-up and after an undervoltage lockout or overvoltage/overcurrent event.

The part is available in a 20-lead wide SO package to support high voltage pin-to-pin clearance.

Applications

  • Isolated Telecommunication Systems
  • Personal Computers and Peripherals
  • Lead Acid Battery Backup Systems
  • Automotive and Heavy Equipment

LT1681
Dual Transistor Synchronous Forward Controller
36V-72V DC to 5V/7A Synchronous Forward Converter (Half-Brick Footprint) Product Package 1
Add to myAnalog

Add product to the Products section of myAnalog (to receive notifications), to an existing project or to a new project.

Create New Project
Ask a Question

Documentation

Data Sheet

This is the most up-to-date revision of the Data Sheet.

Learn More
Add to myAnalog

Add media to the Resources section of myAnalog, to an existing project or to a new project.

Create New Project

Software Resources

Can't find the software or driver you need?

Request a Driver/Software

Tools & Simulations

LTspice


Models for the following parts are available in LTspice:

  • LT1681
LTspice

LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.

Latest Discussions

No discussions on LT1681 yet. Have something to say?

Start a Discussion on EngineerZone®

Recently Viewed