SNOS633N December   1991  – August 2025 LM4040-N , LM4040-N-Q1

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Pin Configuration and Functions
  6. Specifications
    1. 5.1  Absolute Maximum Ratings
    2. 5.2  ESD Ratings
    3. 5.3  Recommended Operating Conditions
    4. 5.4  Thermal Information
    5. 5.5  Electrical Characteristics: 2V LM4040-N VR Tolerance Grades 'A' And 'B'; Temperature Grade 'I'
    6. 5.6  Electrical Characteristics: 2V LM4040-N VR Tolerance Grades 'C', 'D', And 'E'; Temperature Grade 'I'
    7. 5.7  Electrical Characteristics: 2V LM4040-N VR Tolerance Grades 'C', 'D', And 'E'; Temperature Grade 'E'
    8. 5.8  Electrical Characteristics: 2.5V LM4040-N VR Tolerance Grades 'A' And 'B'; Temperature Grade 'I' (AEC Grade 3)
    9. 5.9  Electrical Characteristics: 2.5V LM4040-N VR Tolerance Grades 'C', 'D', and 'E'; Temperature Grade 'I' (AEC Grade 3)
    10. 5.10 Electrical Characteristics: 2.5V LM4040-N VR Tolerance Grades 'C', 'D', And 'E'; Temperature Grade 'E' (AEC Grade 1)
    11. 5.11 Electrical Characteristics: 3V LM4040-N VR Tolerance Grades 'A' And 'B'; Temperature Grade 'I'
    12. 5.12 Electrical Characteristics: 3V LM4040-N VR Tolerance Grades 'C', 'D', And 'E'; Temperature Grade 'I'
    13. 5.13 Electrical Characteristics: 3V LM4040-N VR Tolerance Grades 'C', 'D', And 'E'; Temperature Grade 'E'
    14. 5.14 Electrical Characteristics: 4.1V LM4040-N VR Tolerance Grades 'A' And 'B'; Temperature Grade 'I'
    15. 5.15 Electrical Characteristics: 4.1V LM4040-N VR Tolerance Grades 'C' and 'D'; Temperature Grade 'I'
    16. 5.16 Electrical Characteristics: 5V LM4040-N VR Tolerance Grades 'A' And 'B'; Temperature Grade 'I'
    17. 5.17 Electrical Characteristics: 5V LM4040-N VR Tolerance Grades 'C' And 'D'; Temperature Grade 'I'
    18. 5.18 Electrical Characteristics: 5V LM4040-N VR Tolerance Grades 'C' And 'D'; Temperature Grade 'E'
    19. 5.19 Electrical Characteristics: 8.2V LM4040-N VR Tolerance Grades 'A' And 'B'; Temperature Grade 'I'
    20. 5.20 Electrical Characteristics: 8.2V Lm4040-N VR Tolerance Grades 'C' And 'D'; Temperature Grade 'I'
    21. 5.21 Electrical Characteristics: 10V LM4040-N VR Tolerance Grades 'A' And 'B'; Temperature Grade 'I'
    22. 5.22 Electrical Characteristics: 10V LM4040-N VR Tolerance Grades 'C' And 'D'; Temperature Grade 'I'
    23. 5.23 Typical Characteristics
      1. 5.23.1 Start-Up Characteristics
  7. Parameter Measurement Information
  8. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
    4. 7.4 Device Functional Modes
  9. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Shunt Regulator
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curve
      2. 8.2.2 4.1V ADC Application
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
      3. 8.2.3 Bounded Amplifier
        1. 8.2.3.1 Design Requirements
        2. 8.2.3.2 Detailed Design Procedure
      4. 8.2.4 Protecting Op-Amp Input
        1. 8.2.4.1 Design Requirements
        2. 8.2.4.2 Detailed Design Procedure
      5. 8.2.5 Precision ±4.096V Reference
        1. 8.2.5.1 Design Requirements
        2. 8.2.5.2 Detailed Design Procedure
      6. 8.2.6 Precision Current Sink/Source
        1. 8.2.6.1 Design Requirements
        2. 8.2.6.2 Detailed Design Procedure
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Related Links
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, And Orderable Information
    1. 11.1 SOT-23 and SC70 Package Marking Information

Package Options

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

Detailed Design Procedure

With amplifier rails of ±15V, the output can be bound to ±11.5V with the LM4040-10 and two nominal diode voltage drops of 0.7V.

Equation 5. VOUTBound = 2 × VFWD + VZ
Equation 6. VOUTBound = 1.4V + 10V

Select RS = 15kΩ to keep IR low. Calculate IR to confirm RS selection.

Equation 7. IR = (VIN – VOUT) / R, however in this case, the negative supply must be taken into account.
Equation 8. IR = (VIN+ – VIN- – VOUT)/R = (30V – 10V) / (RS1+RS2) = 20V / 30kΩ = 0.667mA

This is an acceptable value for IR that does not draw excessive current, but prevents the part from being starved for current.