EEHDSGN Real Operational Amplifier Circuits

From 21st Century Products Wiki

Introduction

Basic operational amplifier (op amp) circuits are covered to death elsewhere. What is commonly not discussed, however, is that real-world (industrial, rugged) op amp circuits are NOT the basic ones commonly shown everywhere.

Real-World Op Amp Circuit Considerations

Real-world considerations (for an op amp in an industrial / commercial product) include the following:

  1. Provisions to prevent op amp from oscillation.
  2. Provisions to include filtering on op am input.
  3. Provisions to balance op amp input impedances, especially when filtering is employed.
  4. Picking an appropriate op amp IC type for the project at hand.
  5. And many others.

Basic Op Amp Circuits

It would be useful to start from basic circuits, and immediately observe issues with them:

TODO inverting

TODO its parameters

TODO non-inverting

TODO its parameters

TODO differential

TODO its parameters

Non-ideal op amp behaviors

Operation close to rails

Nonlinearities

Bandwidth

Instability

Preventing op amp oscillation

Adding filtering to op amp circuit

Impedance Balancing

Op amp features

Rail-to-rail input and/or output

Representative modern op amps for common applications

Rugged industrial op amp circuits