SBOSA16 October   2020 OPA455

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  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
    5. 6.5 Electrical Characteristics
    6. 6.6 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 Status Flag Pin
      2. 7.3.2 Thermal Protection
      3. 7.3.3 Current Limit
      4. 7.3.4 Enable and Disable
    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 High DAC Gain Stage for Semiconductor Test Equipment
        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 Improved Howland Current Pump for Bioimpedance Measurements in Multiparameter Patient Monitors
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Thermally-Enhanced PowerPAD™ Package
      2. 10.1.2 PowerPAD™ Integrated Circuit Package Layout Guidelines
      3. 10.1.3 Pin Leakage
      4. 10.1.4 Thermal Protection
      5. 10.1.5 Power Dissipation
      6. 10.1.6 Heat Dissipation
    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™ Simulation Software (Free Download)
        2. 11.1.1.2 TI Precision Designs
        3. 11.1.1.3 WEBENCH® Filter Designer
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

10.1.5 Power Dissipation

Power dissipation depends on power supply, signal, and load conditions. For dc signals, power dissipation is equal to the product of the output current times the voltage across the conducting output transistor, PD = IL (VS – VO). Power dissipation can be minimized by using the lowest possible power-supply voltage necessary to provide the required output voltage swing.

For resistive loads, the maximum power dissipation occurs at a dc output voltage of one-half the power-supply voltage. Dissipation with ac signals is lower because the root-mean square (RMS) value determines heating. The Instruments, Power Amplifier Stress and Power Handling Limitations application bulletin explains how to calculate or measure dissipation with unusual loads or signals.

The OPA455 can supply output currents of up to 45 mA. Supplying this level of current is common for op amps operating from ±15-V supplies. However, with high supply voltages, internal power dissipation of the op amp can be quite high. Relative to the package size, operation from a single power supply (or unbalanced power supplies) can produce even greater power dissipation because a large voltage is impressed across the conducting output transistor. Applications with high power dissipation may require a heat sink or a heat spreader.