SBOS830I September   2017  – October 2021 OPA189 , OPA2189 , OPA4189

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information: OPA189
    5. 7.5 Thermal Information: OPA2189
    6. 7.6 Thermal Information: OPA4189
    7. 7.7 Electrical Characteristics
    8. 7.8 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Operating Characteristics
      2. 8.3.2 Phase-Reversal Protection
      3. 8.3.3 Input Bias Current Clock Feedthrough
      4. 8.3.4 EMI Rejection
      5. 8.3.5 EMIRR +IN Test Configuration
      6. 8.3.6 Electrical Overstress
      7. 8.3.7 MUX-Friendly Inputs
      8. 8.3.8 Noise Performance
      9. 8.3.9 Basic Noise Calculations
    4. 8.4 Device Functional Modes
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 25-kHz Low-Pass Filter
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curve
      2. 9.2.2 Discrete INA + Attenuation for ADC With 3.3-V Supply
      3. 9.2.3 Bridge Amplifier
      4. 9.2.4 Low-Side Current Monitor
      5. 9.2.5 Programmable Power Supply
      6. 9.2.6 RTD Amplifier With Linearization
    3. 9.3 System Examples
      1. 9.3.1 24-Bit, Delta-Sigma, Differential Load Cell or Strain Gauge Sensor Signal Conditioning
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Development Support
        1. 12.1.1.1 TINA-TI™ Simulation Software (Free Download)
        2. 12.1.1.2 TI Precision Designs
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Support Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

8.3.7 MUX-Friendly Inputs

The OPAx189 features a proprietary input stage design that allows an input differential voltage to be applied while maintaining high input impedance. Typically, high-voltage CMOS or bipolar-junction input amplifiers feature anti-parallel diodes that protect input transistors from large VGS voltages that may exceed the semiconductor process maximum and permanently damage the device. Large VGS voltages can be forced when applying a large input step, switching between channels, or attempting to use the amplifier as a comparator.

OPAx189 solves these problems with a switched-input technique that prevents large input bias currents when large differential voltages are applied. This solves many issues seen in switched or multiplexed applications, where large disruptions to RC filtering networks are caused by fast switching between large potentials. OPAx189 offers outstanding settling performance due to these design innovations and built-in slew rate boost and wide bandwidth. The OPAx189 can also be used as a comparator. Differential and common-mode Absolute Maximum Ratings still apply relative to the power supplies.