SNOSBT0L February   2000  – September 2016 LM340

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
    1.     Available Packages
  3. 3 Description
    1.     Fixed Output Voltage Regulator
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 LM340A Electrical Characteristics, VO = 5 V, VI = 10 V
    6. 6.6 LM340 / LM7805 Electrical Characteristics, VO = 5 V, VI = 10 V
    7. 6.7 LM340 / LM7812 Electrical Characteristics, VO = 12 V, VI = 19 V
    8. 6.8 LM340 / LM7815 Electrical Characteristics, VO = 15 V, VI = 23 V
    9. 6.9 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Output Current
      2. 7.3.2 Current Limiting Feature
      3. 7.3.3 Thermal Shutdown
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Shorting the Regulator Input
      2. 8.1.2 Raising the Output Voltage Above the Input Voltage
      3. 8.1.3 Regulator Floating Ground
      4. 8.1.4 Transient Voltages
    2. 8.2 Typical Applications
      1. 8.2.1 Fixed Output Voltage Regulator
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curve
    3. 8.3 System Examples
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Heat Sinking DDPAK/TO-263 and SOT-223 Package Parts
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Related Links
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Community Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

3 Description

The LM340 and LM7805 Family monolithic 3-terminal positive voltage regulators employ internal current-limiting, thermal shutdown and safe-area compensation, making them essentially indestructible. If adequate heat sinking is provided, they can deliver over 1.5-A output current. They are intended as fixed voltage regulators in a wide range of applications including local (on-card) regulation for elimination of noise and distribution problems associated with single-point regulation. In addition to use as fixed voltage regulators, these devices can be used with external components to obtain adjustable output voltages and currents.

Considerable effort was expended to make the entire series of regulators easy to use and minimize the number of external components. It is not necessary to bypass the output, although this does improve transient response. Input bypassing is needed only if the regulator is located far from the filter capacitor of the power supply.

LM7805 is also available in a higher accuracy and better performance version (LM340A). Refer to LM340A specifications in the LM340A Electrical Characterisitcs table.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
LM340x
LM7805 Family		 DDPAK/TO-263 (3) 10.18 mm × 8.41 mm
SOT-223 (4) 6.50 mm × 3.50 mm
TO-220 (3) 14.986 mm × 10.16 mm
TO-3 (2) 38.94 mm x 25.40 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Fixed Output Voltage Regulator

LM340 LM340A LM7805 LM7812 LM7815 00778101.png
*Required if the regulator is located far from the power supply filter.
**Although no output capacitor is needed for stability, it does help transient response. (If needed, use 0.1-μF, ceramic disc).