SBOA583 December   2023 OPA205 , OPA206 , OPA210 , OPA2206 , OPA2210 , OPA2392 , OPA2828 , OPA320 , OPA328 , OPA365 , OPA392 , OPA397 , OPA828

 

  1.   1
  2.   Abstract
  3. 1 Introduction
  4. 2 Circuit Configuration Impact on Common-Mode Range
  5. 3 Practical Input Limitations
  6. 4 Input Phase Reversal (Inversion)
  7. 5 Common-Mode Limitations Inside Bipolar Amplifiers
  8. 6 Common-Mode Limitations Inside CMOS Amplifiers
  9. 7 Rail-to-Rail CMOS Amplifiers
  10. 8 Output Swing Limitations Inside a Bipolar Op Amp
  11. 9 Linearity of Output Swing Specifications
  12. 10Output Voltage Swing vs Output Current
  13. 11Classic Bipolar vs Rail-to-Rail Output Stage for CMOS and Bipolar
  14. 12Rail-to-Rail Output and Open-Loop Gain Dependence
  15. 13Output Short-Circuit Protection
  16. 14Overload Recovery
  17. 15Supply Current During Input and Output Swing Limitations
  18. 16Summary
  19. 17References

Abstract

Exceeding the input or output swing limitations on amplifiers causes distortion on the output signal. This document initially covers the basic methods for calculating these limitations. Next, a simplified explanation of how the limitation occurs on internal transistor topology is covered. The internal operation is described to provide insight to the board-and-system level designer on how different categories of amplifiers behave. For example, the operation of two different types of rail-to-rail common-mode range are compared and contrasted. Each of these topologies has specific advantages and disadvantages related to noise and distortion. Finally, the impact of output current on swing limitations, short-circuit protection, and other topics related to the op amp input and output stage are covered.