LT3085 - Adjustable 500mA Single Resistor Low Dropout Regulator

Features

  • Outputs May be Paralleled for Higher Current and Heat Spreading
  • Output Current: 500mA
  • Single Resistor Programs Output Voltage
  • 1% Initial Accuracy of SET Pin Current
  • Output Adjustable to 0V
  • Current Limit Constant with Temperature
  • Low Output Noise: 40μVRMS (10Hz to 100kHz)
  • Wide Input Voltage Range: 1.2V to 36V
  • Low Dropout Voltage: 275mV
  • < 1mV Load Regulation
  • < 0.001%/ V Line Regulation
  • Minimum Load Current: 0.5mA
  • Stable with Minimum 2.2μF Ceramic Capacitor
  • Current Limit with Foldback and Overtemperature Protected
  • 8-Lead MSOP, and 6-Lead 2mm × 3mm DFN Packages

Typical Application

LT3085 Typical Application
LT3085 Typical Application

Description

The LT3085 is a 500mA low dropout linear regulator that can be paralleled to increase output current or spread heat on surface mounted boards. Designed as a precision current source and voltage follower, this new regulator finds use in many applications requiring high current, adjustability to zero, and no heat sink. The device also brings out the collector of the pass transistor to allow low dropout operation—down to 275mV—when used with a second supply.

A key feature of the LT3085 is the capability to supply a wide output voltage range. By using a reference current through a single resistor, the output voltage is programmed to any level between zero and 36V. The LT3085 is stable with 2.2μF of capacitance on the output, and the IC uses small ceramic capacitors that do not require additional ESR as is common with other regulators.

Internal protection circuitry includes current limiting and thermal limiting. The LT3085 is offered in the 8-lead MSOP and a low profile (0.75mm) 6-lead 2mm × 3mmDFN package (both with an Exposed Pad for better thermal characteristics).

Packaging

For complete and up to date package information and drawings, please refer to our packaging page

DFN-6, MS-8

LT3085 Package Drawing
LT3085 Package Drawing

Order Info

Package Variations and Pricing

Part Number Package Pins Temp Price (1-99) Price (1k)* RoHS Data
LT3085EDCB#PBF DFN 6 E $2.47 View
LT3085EDCB#TRMPBF DFN 6 E $2.47 $1.78 View
LT3085EDCB#TRPBF DFN 6 E $2.47 $1.73 View
LT3085EMS8E#PBF MSOP 8 E $2.62 $1.83 View
LT3085EMS8E#TRPBF MSOP 8 E $1.89 View
LT3085IDCB#PBF DFN 6 I $2.71 View
LT3085IDCB#TRMPBF DFN 6 I $2.71 $1.95 View
LT3085IDCB#TRPBF DFN 6 I $2.71 $1.90 View
LT3085IMS8E#PBF MSOP 8 I $2.86 $2.00 View
LT3085IMS8E#TRPBF MSOP 8 I $2.06 View
LT3085MPMS8E MSOP 8 MP $7.06 $4.94 View
LT3085MPMS8E#PBF MSOP 8 MP $7.06 $4.94 View
LT3085MPMS8E#TR MSOP 8 MP $5.00 View
LT3085MPMS8E#TRPBF MSOP 8 MP $5.00 View
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* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Part Number Description Price Documentation
DC1401A LT3085EDCB Demo Board | Single Resistor, Low Dropout Regulator, 1.7V ≤ VIN ≤ 25V, Vout = 1.2V/1.8V/2.5V/3.3V/5V/Adj @ 500mA $75.00
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Click here to view our complete list of demo boards

Applications

  • High Current All Surface Mount Supply
  • High Efficiency Linear Regulator
  • Post Regulator for Switching Supplies
  • Low Parts Count Variable Voltage Supply
  • Low Output Voltage Power Supplies

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Design Tools

LTspiceIV

LTspice IV is a powerful, fast and free simulation tool, schematic capture and waveform viewer with enhancements and models for improving the simulation of switching regulators. Click here to download LTspice IV

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LT3085

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