SNVS769J March   2000  – December 2014 LM2940-N , LM2940C

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and 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 Electrical Characteristics (5 V and 8 V)
    6. 6.6 Electrical Characteristics (9 V and 10 V)
    7. 6.7 Electrical Characteristics (12 V and 15 V)
    8. 6.8 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 Short-Circuit Current Limit
      2. 7.3.2 Overvoltage Shutdown (OVSD)
      3. 7.3.3 Thermal Shutdown (TSD)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Operation with Enable Control
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 External Capacitors
          1. 8.2.2.1.1 Minimum Capacitance
          2. 8.2.2.1.2 ESR Limits
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Examples
    3. 10.3 Heatsinking
      1. 10.3.1 Heatsinking TO-220 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 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • NDE|3
  • NGN|8
  • DCY|4
  • KTT|3
  • NEB|3
Thermal pad, mechanical data (Package|Pins)
Orderable Information

1 Features

  • Input Voltage Range = 6 V to 26 V
  • Dropout Voltage Typically 0.5 V at IOUT = 1 A
  • Output Current in Excess of 1 A
  • Output Voltage Trimmed Before Assembly
  • Reverse Battery Protection
  • Internal Short Circuit Current Limit
  • Mirror Image Insertion Protection
  • P+ Product Enhancement Tested

2 Applications

  • Post Regulator for Switching Supplies
  • Logic Power Supplies
  • Industrial Instrumentation

3 Description

The LM2940-N and LM2940C positive voltage regulators feature the ability to source 1 A of output current with a dropout voltage of typically 0.5 V and a maximum of 1 V over the entire temperature range. Furthermore, a quiescent current reduction circuit has been included which reduces the ground current when the differential between the input voltage and the output voltage exceeds approximately 3 V. The quiescent current with 1 A of output current and an input-output differential of 5 V is therefore only 30 mA. Higher quiescent currents only exist when the regulator is in the dropout mode (VIN − VOUT ≤ 3 V).

Designed also for vehicular applications, the LM2940-N and LM2940C and all regulated circuitry are protected from reverse battery installations or 2-battery jumps. During line transients, such as load dump when the input voltage can momentarily exceed the specified maximum operating voltage, the regulator will automatically shut down to protect both the internal circuits and the load. The LM2940-N and LM2940C cannot be harmed by temporary mirror-image insertion. Familiar regulator features such as short circuit and thermal overload protection are also provided.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
LM2940-N SOT-223 (4) 6.50 mm x 3.50 mm
WSON (8) 4.00 mm x 4.00 mm
TO-263 (3) 10.18 mm x 8.41 mm
TO-220 (3) 14.986 mm x 10.16 mm
LM2940C TO-263 (3) 10.18 mm x 8.41 mm
TO-220 (3) 14.986 mm x 10.16 mm
  1. For all available packages, see the orderable addendum at the end of the datasheet.