SBOSAA7 September   2025 OPA598

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
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Current Limit
      2. 6.3.2 Overcurrent Flag
      3. 6.3.3 Overtemperature Flag
      4. 6.3.4 Enable and Disable
      5. 6.3.5 Mux-Friendly Inputs
    4. 6.4 Device Functional Modes
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 High Voltage 2:1 Multiplexer With Unity Gain
        1. 7.2.1.1 Design Requirements
        2. 7.2.1.2 Detailed Design Procedure
      2. 7.2.2 Output Driver
        1. 7.2.2.1 Design Requirements
        2. 7.2.2.2 Detailed Design Procedure
        3. 7.2.2.3 Application Curve
      3. 7.2.3 Parallel Op Amps
      4. 7.2.4 Composite Amplifier
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
        1. 7.4.1.1 Thermal Considerations
      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. 8.1.1.2 TINA-TI™ Simulation Software (Free Download)
        3. 8.1.1.3 TI Precision Designs
    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

7.2.1.2 Detailed Design Procedure

In this design example, two OPA598 precision op amps are configured as a unity gain buffers powered with a ±42.5V dual supply. The input signal to either amplifier can range from –40V to +39V to remain in linear operation. The output of the amplifiers are connected together and a 3V or 5V logic signal, serving as the output select, is used to toggle between the enable and disable modes of operation. The logic control signal is directly applied to one OPA598 E/D pin, and an inverter gate is used to drive the other OPA598 E/D pin. Figure 7-1 shows a simplified representation of this circuit.

A clear benefit of this design is the high-voltage capability, along with the thermal protection, overcurrent protection, and current-limit features. The mux-friendly input of the OPA598 provides a full input differential range, avoiding the pitfalls of other amplifiers with traditional back-to-back diodes in this configuration. This design can also be reconfigured to include signal gain, but careful selection of the input and feedback resistors is required to minimize current leakage paths.