**Operational Amplifier Applications:**

The countless simple circuits using one or more operational amplifiers, some external resistors and the capacitors can be constructed. Such Operational Amplifier Applications are classified as

- Linear applications of op amp
- Non linear applications of op amp

**Linear Applications of Op Amp:**

In the Linear type of Applications, output voltage varies linearly with respect to the input voltage. The negative feedback is the base of linear applications. Some of the linear applications are **voltage follower**, **differential amplifier**, **instrumentation amplifier**, **inverting amplifier**, **Non inverting amplifier** etc.

**Non Linear Applications of Op Amp:**

In the nonlinear type of applications, a feedback is provided from the output to the input terminal. The feedback may be provided to the inverting input terminal using nonlinear elements like diodes, transistors etc. The nonlinear input to output characteristics is the feature of nonlinear applications. The typical nonlinear applications are **precision rectifiers**, **comparators**, **clampers**, **limiters**, **schmitt trigger circuit** etc.

While deriving the expressions and analyzing such circuits, the **realistic assumptions** can be conveniently used. The op-amp input current is zero while the potential difference between inverting and non inverting terminals is zero. Thus if one terminal is grounded, then potential of other terminal can be assumed zero i.e. it is also at ground potential. This is the concept of virtual ground, which plays an important role in analyzing the Operational Amplifier Applications circuits.