SNOAA35C april   2019  – april 2023 LM2901 , LM2901B , LM2901B-Q1 , LM2903 , LM2903-Q1 , LM2903B , LM2903B-Q1 , LM339 , LM339-N , LM393 , LM393-N , LM393B , LM397 , TL331 , TL331-Q1 , TL331B

 

  1.   Application Design Guidelines for LM339, LM393, TL331 Family Comparators Including the New B-versions
  2.   Trademarks
  3. 1Devices Covered in Application Note
    1. 1.1 Base Part Numbers
    2. 1.2 Input Voltage Offset Grades
    3. 1.3 Maximum Supply Voltage
    4. 1.4 High Reliability Options
    5. 1.5 New TL331B, TL391B, LM339B, LM393B, LM2901B and LM2903B B Versions
  4. 2Input Considerations
    1. 2.1  Input Stage Schematic – The Classic LM339 Family
    2. 2.2  Input Stage Schematic - New TL331B, LM393B and LM2903B B devices
    3. 2.3  Differences Between the Classic and B Die Devices
    4. 2.4  PCN to Change Classic Die to a New Die Design
    5. 2.5  Input Voltage Range
    6. 2.6  Input Voltage Range vs. Common Mode Voltage Range
    7. 2.7  Reason for Input Range Headroom Limitation
    8. 2.8  Input Voltage Range Feature
    9. 2.9  Negative Input Voltages
    10. 2.10 Phase Reversal
    11. 2.11 Output to Input Cross-Talk
    12. 2.12 Protecting Inputs from Negative Voltages
      1. 2.12.1 Simple Resistor and Diode Clamp
      2. 2.12.2 Voltage Divider with Clamp
        1. 2.12.2.1 Split Voltage Divider with Clamp
  5. 3Output Stage Considerations
    1. 3.1 Output VOL and IOL
    2. 3.2 Pull-Up Resistor Selection
    3. 3.3 Short Circuit Sinking Current
    4. 3.4 Pulling Output Up Above VCC
    5. 3.5 Negative Voltages Applied to Output
    6. 3.6 Adding Large Filter Capacitors To Output
  6. 4Power Supply Considerations
    1. 4.1 Supply Bypassing
      1. 4.1.1 Low VCC Guidance
      2. 4.1.2 Split Supply use
  7. 5General Comparator Usage
    1. 5.1 Unused Comparator Connections
      1. 5.1.1 Do Not Connect Inputs Directly to Ground
      2. 5.1.2 Unused Comparator Input Connections
      3. 5.1.3 Leave Outputs Floating
      4. 5.1.4 Prototyping
  8. 6Conclusion
  9. 7Related Documentation
    1. 7.1 Related Links
  10. 8Revision History

1 Application Design Guidelines for LM339, LM393, TL331 Family Comparators Including the New B-versions

The TL331, LM339, LM393, and the next generation B-versions (TL331B, LM339B, LM2901B, LM393B and LM2903B) are a popular and long-lived family of standard comparators due to their flexibility, availability, and cost-effectiveness. It is important to understand how these comparators are different than most other comparators before using them in your design. The information in this application guide will help promote first time design successes. The front page of the B data sheets contains a table showing the differences in specifications between the various classic devices and the new B device.