SBOA602 November   2024 OPA593

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Current Booster, Push-Pull Topology Output Characteristics
    1. 2.1 Open-Loop Output Impedance
    2. 2.2 Minimizing Zero Crossover Distortion
  6. 3Various Current Booster Configurations
    1. 3.1 Complementary MOSFET versus BJT Current Booster Comparisons
  7. 4Stabilizing a Design for Power Amplifier Driving 1μF Capacitive Load (CL)
    1. 4.1 Op-Amp Driving Resistive Load
    2. 4.2 Op-Amp Driving Capacitive Load and Challenges
    3. 4.3 Open-Loop AC Stability Analysis - Compensating CL Effects Using DFC
    4. 4.4 Closed-Loop Stability Response - Small Signal Step Transient Analysis
    5. 4.5 Effects of Riso on Frequency Response in Dual Feedback Compensation
    6. 4.6 Summary of the DFC Technique
  8. 5Stabilizing the OPA593 and Darlington Current Booster for 1μF Capacitive Load
    1. 5.1 Open-Loop AC Stability Analysis - Composite Op-Amp Driving 1μF CL
    2. 5.2 Closed-Loop Stability Response - Composite Op-Amp's Step Transient Analysis
  9. 6Composite Amplifier's Effective BW and Step Time Response
  10. 7Test Bench Validation
  11. 8Summary
  12. 9References

Abstract

Since the introduction of the OPA593, the power operational amplifier (PA) has gained traction in the test and measurement sector. Specifically designed for Automated Test Equipment (ATE) applications, the OPA593 can drive output voltages up to 80V and output currents up to ±250mA, all within a compact 4mm × 4mm WSON package. The OPA593 operates across the full industrial temperature range of -40°C to 125°C, providing exceptional DC precision and robust output current limiting features that cater to diverse design requirements in ATE applications.

This application note demonstrates how to compensate for the OPA593 PA and current booster configuration, enabling output driving currents up to ±1A. Additionally, the document explains the implementation of the op amp’s dual feedback compensation techniques when driving capacitive loads of up to 1μF, making sure of adequate phase margin, stabilizing loop gains through AC analysis, and achieving fast step time responses in ATE applications.