SNOAA35F April   2019  – December 2024 LM2901 , LM2901B , LM2901B-Q1 , LM2903 , LM2903-Q1 , LM2903B , LM2903B-Q1 , LM339 , LM339-N , LM393 , LM393-N , LM393B , LM397 , TL331 , TL331-Q1 , TL331B

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1 Devices 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. 2 The New TL331B, TL391B, LM339B, LM393B, LM2901B and LM2903B B Versions
  6. 3 PCN's to Change Classic Die to a New Die Design
    1. 3.1 PCN #1 for Single and Dual (TL331 and LMx93/LM2903)
    2. 3.2 PCN #2 for Single and Dual (TL331 and LMx93/LM2903)
    3. 3.3 PCN For Quad (LMx39, LM2901)
    4. 3.4 PCN for B Devices (including -Q1's)
    5. 3.5 Device PCN Summary
    6. 3.6 Determining Die Version Used
      1. 3.6.1 Determine Die Used for Single TL331 and Dual LM293, LM393, and LM2903 - PCN #1 (Ji3)
      2. 3.6.2 Determine Die Used for Single TL331 and Dual LM293, LM393, and LM2903 - PCN #2 (TiB)
      3. 3.6.3 Determine Die Used for Quad LM139, LM239, LM339, and LM2901
      4. 3.6.4 Determine Die Used for Post-PCN B Devices
  7. 4 Changes to Package Top Markings
  8. 5 Roughened Leadframe Finish
  9. 6 Input Considerations
    1. 6.1  Input Stage Schematic – The Classic LM339 Family
    2. 6.2  Input Stage Schematic - New "B" and TiB Devices
    3. 6.3  Differences Between the Classic, "B" and Tib Die Devices
    4. 6.4  Input Voltage Range
    5. 6.5  Input Voltage Range vs. Common Mode Voltage Range
    6. 6.6  Reason for Input Range Headroom Limitation
    7. 6.7  Input Voltage Range Feature
    8. 6.8  Both Inputs Above Input Range Behavior
    9. 6.9  Negative Input Voltages
      1. 6.9.1 Maximum Input Current
      2. 6.9.2 Phase Reversal or Inversion
      3. 6.9.3 Protecting Inputs from Negative Voltages
        1. 6.9.3.1 Simple Resistor and Diode Clamp
        2. 6.9.3.2 Voltage Divider with Clamp
          1. 6.9.3.2.1 Split Voltage Divider with Clamp
    10. 6.10 Power-Up Behavior
    11. 6.11 Capacitors and Hysteresis
    12. 6.12 Output to Input Cross-Talk
  10. 7 Output Stage Considerations
    1. 7.1 Output VOL and IOL
    2. 7.2 Pull-Up Resistor Selection
    3. 7.3 Short Circuit Sinking Current
    4. 7.4 Pulling Output Up Above Vcc
    5. 7.5 Negative Voltages Applied to Output
    6. 7.6 Adding Large Filter Capacitors To Output
  11. 8 Power Supply Considerations
    1. 8.1 Supply Bypassing
      1. 8.1.1 Low VCC Guidance
      2. 8.1.2 Split Supply use
  12. 9 General Comparator Usage
    1. 9.1 Unused Comparator Connections
      1. 9.1.1 Do Not Connect Inputs Directly to Ground
      2. 9.1.2 Unused Comparator Input Connections
      3. 9.1.3 Leave Outputs Floating
      4. 9.1.4 Prototyping
  13. 10PSpice and TINA TI Models
  14. 11Conclusion
  15. 12Related Documentation
    1. 12.1 Related Links
  16. 13Revision History

6.9.1 Maximum Input Current

A commonly misinterpreted specification is the Maximum Input Current or Input Current specification as listed in the Absolute Maximum Table. For this family, the specification can be as high as 50mA (typically listed as -50mA).

This current is actually the maximum current that can be passed through the reverse biased substrate diode without damage, though the specification does not imply proper operation at that time. This current is seen when a negative voltage is applied to the input attempting to pull the input below the GND pin (-0.5V to -1V). This specification sets a limit on the current as mentioned in the previous section on Negative Input Voltages. At 50mA, improper operation and malfunctions are possible. TI still recommends keeping the current to below 10mA or less.

This specification does NOT relate to a maximum input bias current. When the input voltage is within proper specified operating range (0V to Vcc-2V), the input current can be within the Electrical Specification Tables for maximum bias current (<500nA) and must never approach the milliamp range under normal operation.