SBOS737C January   2016  – March 2018 OPA197 , OPA2197 , OPA4197

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      OPA197 in a High-Voltage, Multiplexed, Data-Acquisition System
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions: OPA197
    2.     Pin Functions: OPA2197 and OPA4197
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information: OPA197
    5. 6.5 Thermal Information: OPA2197
    6. 6.6 Thermal Information: OPA4197
    7. 6.7 Electrical Characteristics: VS = ±4 V to ±18 V (VS = 8 V to 36 V)
    8. 6.8 Electrical Characteristics: VS = ±2.25 V to ±4 V (VS = 4.5 V to 8 V)
    9. 6.9 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Input Protection Circuitry
      2. 7.3.2 EMI Rejection
      3. 7.3.3 Phase Reversal Protection
      4. 7.3.4 Thermal Protection
      5. 7.3.5 Capacitive Load and Stability
      6. 7.3.6 Common-Mode Voltage Range
      7. 7.3.7 Electrical Overstress
      8. 7.3.8 Overload Recovery
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 16-Bit Precision Multiplexed Data-Acquisition System
        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 Slew Rate Limit for Input Protection
      3. 8.2.3 Precision Reference Buffer
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 TINA-TI (Free Software Download)
        2. 11.1.1.2 TI Precision Designs
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Related Links
    4. 11.4 Receiving Notification of Documentation Updates
    5. 11.5 Community Resources
    6. 11.6 Trademarks
    7. 11.7 Electrostatic Discharge Caution
    8. 11.8 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.1 Input Protection Circuitry

The OPAx197 uses a unique input architecture to eliminate the need for input protection diodes, but still provides robust input protection under transient conditions. Conventional input diode protection schemes shown in Figure 41 can be activated by fast transient step responses and can introduce signal distortion and settling time delays because of alternate current paths, as shown in Figure 42. For low-gain circuits, these fast-ramping input signals forward-bias back-to-back diodes, causing an increase in input current, and resulting in extended settling time, as shown in Figure 43.

OPA197 OPA2197 OPA4197 input_protection_sbos737.gifFigure 41. OPA197 Input Protection Does Not Limit Differential Input Capability
OPA197 OPA2197 OPA4197 ai_back_to_back_bos620.gifFigure 42. Back-to-Back Diodes Create Settling Issues
OPA197 OPA2197 OPA4197 D038_SBOS737.gifFigure 43. OPA197 Protection Circuit Maintains Fast-Settling Transient Response

The OPAx197 family of operational amplifiers provides a true high-impedance differential input capability for high-voltage applications. This patented input protection architecture does not introduce additional signal distortion or delayed settling time, making the device an optimal op amp for multichannel, high-switched, input applications. The OPA197 can tolerate a maximum differential swing (voltage between inverting and noninverting pins of the op amp) of up to 36 V, making the device suitable for use as a comparator or in applications with fast-ramping input signals such as multiplexed data-acquisition systems, as shown in Figure 53.