Datasheet Linear Technology LT1425

Datasheets

Packaging

Parametrics

Eco Plan

Application Notes

• Download
  Linear Technology Magazine Circuit Collection, Volume IV &mdash AN84
  PDF, 2.4 Mb, File published: Apr 1, 2000
  Application Note 84 is a collection of "power circuits" from the years 1996 through 1998 as seen in the pages of Linear Technology magazine. This Application Note collects circuits that can output tens of amps to circuits that can operate a handheld device for several years. In addition to a wide variety of traditional power supply circuits (Buck, Boost, Inverting, Flyback, Linear Regulators, etc.) we include circuits for charging batteries, several Power Management circuits as well as circuits that highlight a very low noise switching regulator.
  Extract from the document

  Application Note 84
  April 2000 Linear Technology Magazine Circuit Collection, Volume IV
  Power Products
  Richard Markell, Editor
  INTRODUCTION
  Application Note 84 is the fourth in a series that excerpts
  useful circuits from Linear Technology magazine to preserve them for posterity. This application note highlights
  “power” circuits from issue VI:1 (February 1996) through
  issue VIII:4 (November 1998). Another application note
  will feature data conversion, interface and signal processing circuits from the same era. Like its predecessor, AN 66,
  this Application Note includes circuits that can power
  most any system you can imagine, from “server” power
  supplies that generate in excess of 50 amps to micropower systems for portable and handheld equipment.
  Also included are power converters that can be voltage programmed using Intel’s VID code. Charge pump converters, linear regulators and battery charger circuits are
  included here, with Li-Ion batteries receiving extra attention. There are, of course, circuits that cannot be so simply
  categorized. Come browse. I’ll get out of the way and let
  the authors describe their creations.
  Note: Article Titles appear in this application note exactly
  as they originally appeared in Linear Technology magazine. This may result in some inconsistency in the usage
  of terminology. TABLE OF CONTENTS
  Introduction . 1
  REGULATORS—SWITCHING (BUCK)
  New LTCВ®1435–LTC1439 DC/DC Controllers Feature Value and Performance . 4 …

Design Notes

• Download
  Isolated DC/DC Conversion with the LT1425 &mdash DN158
  PDF, 81 Kb, File published: Jul 1, 1997
  Extract from the document

  Isolated DC/DC Conversion with the LT1425 – Design Note 158
  Kurk Mathews
  The LT В®1425 is designed for applications requiring well
  regulated, isolated voltages, such as isolation amplifiers,
  remote sensors and telecommunication interfaces. A
  unique feedback amplifier eliminates the need to cross
  the isolation barrier twice, resulting in a simpler, lower
  parts count supply. The LT1425, available in 16-pin SO,
  is a 275kHz current mode controller with an integral 1.5A
  switch, designed primarily to provide well regulated,
  isolated voltages from 3V to 20V sources.
  Figure 1 shows a typical flyback LAN supply, including
  an alternate transformer for a complete PCMCIA type II
  height solution. Load regulation is В±1% for output currents of 0mA to 250mA. Feedback is accomplished
  by averaging the flyback voltage on the primary side
  of T1. The internal switch is located between the VSW
  and PGND pins. The RFB pin is internally biased to VIN.
  During the switch off-time, a feedback current proportional to VOUT/n (n is the transformer’s turn ratio)
  is developed into the RFB pin (via R4). Flyback voltage
  on T1 is not present during the switch on-time or when
  the secondary current decays to zero (discontinuous flyback mode). Collapse-detect and blanking circuitry
  ensure that the feedback amplifier ignores information
  during these times. …

Model Line

Manufacturer's Classification

• Power Management > Switching Regulator > Flyback, Forward and Isolated Controllers