SBOS062D September   2000  – December 2025 INA126 , INA2126

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: INA126
    5. 5.5 Thermal Information: INA2126
    6. 5.6 Electrical Characteristics
    7. 5.7 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
    4. 6.4 Device Functional Modes
      1. 6.4.1 Single-Supply Operation
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Setting the Gain
        2. 7.2.2.2 Offset Trimming
        3. 7.2.2.3 Input Bias Current Return
        4. 7.2.2.4 Input Common-Mode Range
        5. 7.2.2.5 Input Protection
        6. 7.2.2.6 Channel Crosstalk—Dual Version
      3. 7.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
      1. 7.3.1 Low-Voltage Operation
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Development Support
        1. 8.1.1.1 PSpice® for TI
      2. 8.1.2 Device Nomenclature
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

7.2 Typical Application

Figure 7-1 shows the basic connections required for operation of the INA126. Applications with noisy or high impedance power supplies can require decoupling capacitors close to the device pins as shown.

The output is referred to the output reference (Ref) pin, which is normally grounded. This connection must be low-impedance to maintain good common-mode rejection. A resistance of 8Ω in series with the Ref pin causes a typical device to degrade to approximately 80dB CMR.

Figure 7-4 depicts a desired differential signal from a sensor at 1kHz and 5mVPP superimposed on top of a 1VPP, 60Hz common-mode signal (the 1kHz signal can not be resolved in this scope trace). The FFT trace in Figure 7-5 shows the two signals. Figure 7-6 shows the clearly recovered differential signal at the output of the INA126 operating at a gain of 250. The FFT of Figure 7-7 shows the 60Hz common-mode is no longer visible.

The dual version INA2126 has feedback-sense connections, SenseA and SenseB, that must be connected to the respective output pins for proper operation. The sense connection can sense the output voltage directly at the load for best accuracy.

INA126 INA2126 Basic ConnectionsFigure 7-1 Basic Connections