Datasheet Linear Technology LT3080

Datasheets

Prices

Packaging

Parametrics

Eco Plan

Application Notes

• Download
  2-Wire Virtual Remote Sensing for Voltage Regulators - Clairvoyance Marries Remote Sensing &mdash AN126
  PDF, 1.4 Mb, File published: Oct 1, 2010
  Wires and connectors have resistance. This simple, unavoidable truth dictates that a power source’s remote load voltage will be less than the source’s output voltage. Traditional methods for countering this include increasing the power source voltage and "4-wire" remote voltage sensing. Both have limitations. A new IC based approach achieves "virtual" remote sensing at the load without adding the usual two extra sense wires. Numerous circuit examples show the IC working with various voltage regulators and remote loads. Appendices detail IC internal operation and design guidelines for applying the part in any regulator circuit.
  Extract from the document

  Application Note 126
  October 2010
  2-Wire Virtual Remote Sensing for Voltage Regulators
  Clairvoyance Marries Remote Sensing
  Jim Williams, Jesus Rosales, Kurk Mathews, Tom Hack
  Introduction
  Wires and connectors have resistance. This simple, unavoidable truth dictates that a power source’s remote load
  voltage will be less than the source’s output voltage. Figure 1
  shows this, and implies that intended load voltage can
  be maintained by raising regulator output. Unfortunately,
  line resistance and load variations introduce uncertainties,
  limiting achievable performance.
  WIRING DROPS POWER
  SUPPLY LOAD
  AN125 F01 WIRING DROPS Figure 1. Unavoidable Wiring Drops Cause Low Load
  Voltage. Line and Load Resistance Variations Introduce
  Additional Load Voltage Uncertainty, Mitigating Against
  Compensation by Raising Supply Voltage LOAD
  VOLTAGE
  REGULATOR POWER
  SUPPLY LOAD
  AN125 F02 Figure 2. Local Regulation Stabilizes
  Load Voltage But is Inefп¬Ѓcient VOUT+ VOLTAGE DROP Figure 2 illustrates one compensatory approach. Locally …

• Download
  Basic Concepts of Linear Regulator and Switching Mode Power Supplies &mdash AN140
  PDF, 715 Kb, File published: Oct 1, 2013
  Extract from the document

  Application Note 140
  October 2013
  Basic Concepts of Linear Regulator and Switching
  Mode Power Supplies
  Henry J. Zhang
  ABSTRACT
  This article explains the basic concepts of linear regulators
  and switching mode power supplies (SMPS). It is aimed
  at system engineers who may not be very familiar with
  power supply designs and selection. The basic operating
  principles of linear regulators and SMPS are explained
  and the advantages and disadvantages of each solution
  are discussed. The buck step-down converter is used as
  an example to further explain the design considerations
  of a switching regulator.
  INTRODUCTION
  Today’s designs require an increasing number of power
  rails and supply solutions in electronics systems, with
  loads ranging from a few mA for standby supplies to over
  100A for ASIC voltage regulators. It is important to choose
  the appropriate solution for the targeted application and
  to meet specified performance requirements, such as
  high efficiency, tight printed circuit board (PCB) space, …

Design Notes

• Download
  1.5A Rail-to-Rail Output Synchronous Step-Down Regulator Adjusts with a Single Resistor &mdash DN506
  PDF, 520 Kb, File published: Mar 13, 2012
  Extract from the document

  1.5A Rail-to-Rail Output Synchronous Step-Down Regulator
  Adjusts with a Single Resistor
  Design Note 506
  Jeff Zhang
  Introduction
  A new regulator architecture the LTC3600 (first introduced with the LT3080 linear regulator) has wider output
  range and better regulation than traditional regulators.
  Using a precision 50ВµA current source and a voltage
  follower, the output is adjustable from “0V” to close
  to VIN. Normally, the lowest output voltage is limited
  to the reference voltage. However, this new regulator
  has a constant loop gain independent of the output
  voltage giving excellent regulation at any output and
  allowing multiple regulators to be paralleled for higher
  output currents.
  Operation
  The LTC3600 is a current mode monolithic step-down
  buck regulator with excellent line and load transient
  responses. The 200kHz to 4MHz operating frequency
  can be set by a resistor or synchronized to an external
  clock. The LTC3600 internally generates an accurate
  50ОјA current source, allowing the use of a single external LTC3600 VIN VIN
  12V resistor to program the reference voltage from 0V to …

• Download
  Control the Voltage of a Remote Load Over Any Length of Copper Wire &mdash DN529
  PDF, 190 Kb, File published: Jul 8, 2014
  Extract from the document

  Control the Voltage of a Remote Load Over Any Length
  of Copper Wire – Design Note 529
  Philip Karantzalis
  Introduction
  A common problem in power distribution systems is
  loss of regulation due to the cable/wire voltage drop
  between the regulator and the load. Any increase in
  wire resistance, cable length or load current increases
  the voltage drop over the distribution wire, increasing
  the difference between actual voltage at the load and
  the voltage perceived by the regulator. One way to
  improve regulation over long cable runs is to measure
  voltage directly at the load via a 4-wire Kelvin connection between the regulator and the load. Unfortunately,
  this solution requires routing additional wires to the
  load as well as a Kelvin resistor placed near the load,
  impractical when the load is inaccessible for modification. Another method minimizes the voltage drop by
  employing large diameter wire, lowering the resistance
  from the regulator to the load. This is electrically simple,
  but can be mechanically complicated. Increasing the
  size of cable conductors can significantly increase
  space requirements and cost. The LT6110 Cable/Wire Compensator
  Figure 1 shows a 1-wire compensation block diagram.
  If the remote load circuit does not share the regulator’s ground, two wires are required, one to the load …

Articles

• Download
  New Linear Regulators Solve Old Problems &mdash LT Journal
  PDF, 807 Kb, File published: Jan 6, 2014
  Extract from the document

  January 2014 I N T H I S I S S U E ВµModuleВ® regulator
  combines a switcher with
  five 1.1A LDOs 12 Volume 23 Number 4 New Linear Regulators
  Solve Old Problems
  Bob Dobkin fully differential op amp
  drives high res ADCs 14 Silent Switcherв„ў regulator
  meets CISPR Class 5 25 high speed ADC sampling
  transients 34 The architecture of linear regulators has remained virtually
  unchanged since the introduction of the 3-terminal floating
  voltage regulator in 1976. Architectures have settled on either the
  floating architecture (LT317) or an amplifier loop with feedback
  from the output to the amplifier. These architectures inherently
  limit regulator versatility, regulation and accuracy. In 2007, Linear
  Technology released the LTВ®3080, introducing a new linear regulator
  architecture that expanded versatility,
  significantly improved performance,
  and allowed easy parallel operation.
  The LT3081 is one of this new
  class of linear regulator, specifically
  featuring a wide safe operating
  area for industrial applications.
  THE OLD WAY In the old linear regulator architecture (Figure 1),
  feedback resistors set the output voltage and attenuate …

• Download
  Low Dropout Regulator Can Be Directly Paralleled to Spread The Heat &mdash LT Journal
  PDF, 1.6 Mb, File published: Oct 16, 2007
  Extract from the document

  LINEAR TECHNOLOGY OCTOBER 2007 IN THIS ISSUE…
  Cover Article
  Low Dropout Regulator Can Be Directly
  Paralleled to Spread The Heat.1
  Robert Dobkin Linear in the News….2
  Design Features
  16-Channel LED Driver Drives up to 160
  White LEDs with 5000:1 PWM Dimming
  .6
  Keith Szolusha 2-Phase Synchronous Buck Controller
  Delivers Maximum Features in
  Minimum Footprint.10
  Eric Gu and Theo Phillips Measure Microamps to Amps or Reduce
  Power Dissipation by 99%, You Decide!
  .13
  Brendan J. Whelan Pushbutton On/Off Controller Provides
  ВµProcessor Reset Monitor and Input
  Supply Monitoring.17
  Victor Fleury LED Driver Yields 3000:1 True Color
  PWM Dimming with Any Buck, Boost
  or Buck-Boost Topology from a Wide
  3V–40V Input Range.20
  Xin Qi White LED Driver and OLED Driver …

Model Line

Manufacturer's Classification

• Power Management > LDO Linear Regulators > Positive Linear Regulators (LDO)
• Power Management > Current Sources