SNVS038H July 1999  – January 2015 LM1085

PRODUCTION DATA. 

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  6. Specifications
    1. 6.1Absolute Maximum Ratings
    2. 6.2ESD Ratings
    3. 6.3Recommended Operating Conditions
    4. 6.4Thermal Information
    5. 6.5Electrical Characteristics
    6. 6.6Typical Characteristics
  7. Detailed Description
    1. 7.1Overview
    2. 7.2Functional Block Diagram
    3. 7.3Feature Description
      1. 7.3.1Ripple Rejection
      2. 7.3.2Load Regulation
      3. 7.3.3Overload Recovery
    4. 7.4Device Functional Modes
      1. 7.4.1Output Voltage
      2. 7.4.2Stability Consideration
      3. 7.4.3Protection Diodes
  8. Application and Implementation
    1. 8.1Application Information
    2. 8.2Typical Applications
      1. 8.2.1 1.2-V to 15-V Adjustable Regulator
        1. 8.2.1.1Design Requirements
        2. 8.2.1.2Detailed Design Procedure
        3. 8.2.1.3Application Curve
      2. 8.2.2 Adjustable at 5 V
      3. 8.2.3 5-V Regulator with Shutdown
      4. 8.2.4 Battery Charger
      5. 8.2.5 Adjustable Fixed Regulator
      6. 8.2.6 Regulator with Reference
      7. 8.2.7 High Current Lamp Driver Protection
      8. 8.2.8 Battery Backup Regulated Supply
      9. 8.2.9 Ripple Rejection Enhancement
      10. 8.2.10Automatic Light Control
      11. 8.2.11Generating Negative Supply Voltage
      12. 8.2.12Remote Sensing
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1Layout Guidelines
    2. 10.2Layout Example
    3. 10.3Thermal Considerations
  11. 11Device and Documentation Support
    1. 11.1Documentation Support
      1. 11.1.1Related Documentation
    2. 11.2Trademarks
    3. 11.3Electrostatic Discharge Caution
    4. 11.4Glossary
  12. 12Mechanical, Packaging, and Orderable Information

1 Features

  • Available in 3.3-V, 5.0-V, 12-V and Adjustable Versions
  • Current Limiting and Thermal Protection
  • Output Current 3 A
  • Line Regulation 0.015% (typical)
  • Load Regulation 0.1% (typical)

2 Applications

  • High Efficiency Linear Regulators
  • Battery Charger
  • Post Regulation for Switching Supplies
  • Constant Current Regulator
  • Microprocessor Supply

3 Description

The LM1085 is a regulator with a maximum dropout of 1.5 V at 3 A of load current. It has the same pin-out as TI's industry standard LM317.

Two resistors are required to set the output voltage of the adjustable output voltage version of the LM1085. Fixed output voltage versions integrate the adjust resistors.

The LM1085 circuit includes a zener trimmed bandgap reference, current limiting and thermal shutdown.

Refer to the LM1084 for the 5A version, and the LM1086 for the 1.5A version.

Device Information(1)

PART NUMBERPACKAGEBODY SIZE (NOM)
LM1085DDPAK/TO-263 (3) 10.18 mm × 8.41 mm
TO-220 (3) 14.986 mm × 10.16 mm
  1. For all available packages, see the orderable addendum at the end of the datasheet.

Typical Application

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