SLOS066AD September   1975  – October 2024 LM124 , LM124A , LM124M , LM224 , LM224A , LM224K , LM224KA , LM2902 , LM2902B , LM2902BA , LM2902K , LM2902KAV , LM2902KV , LM324 , LM324A , LM324B , LM324BA , LM324K , LM324KA

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 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 - LM324B and LM324BA
    6. 5.6  Electrical Characteristics - LM2902B and LM2902BA
    7. 5.7  Electrical Characteristics for LM324, LM324K, LM224, LM224K, and LM124
    8. 5.8  Electrical Characteristics for LM2902, LM2902K, LM2902KV and LM2902KAV
    9. 5.9  Electrical Characteristics for LM324A, LM324KA, LM224A, LM224KA, and LM124A
    10. 5.10 Operating Conditions
    11. 5.11 Typical Characteristics
    12. 5.12 Typical Characteristics: All Devices Except B and BA Versions
  7. 6 Parameter Measurement Information
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Unity-Gain Bandwidth
      2. 7.3.2 Slew Rate
      3. 7.3.3 Input Common Mode Range
    4. 7.4 Device Functional Modes
  9. 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
      3. 8.2.3 Application Curve
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Examples
  10. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Electrostatic Discharge Caution
    5. 9.5 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information
    1. 11.1 Package Option Addendum
    2. 11.2 Tape and Reel Information

8.2.2 Detailed Design Procedure

Determine the gain required by the inverting amplifier using Equation 1 and Equation 2:

Equation 1. A V =   V O U T V I N
Equation 2. A V =   1.8 - 0.5   =   - 3.6

Once the desired gain is determined, choose a value for RI or RF. Choosing a value in the kΩ range is desirable because the amplifier circuit uses currents in the mA range. This choice makes sure that the part does not draw too much current. This example chooses 10 kΩ for RI, which means 36 kΩ is used for RF. This was determined by Equation 3.

Equation 3. A V =   R F R I