Technology

An operation amplifier, also known as an op-amp is a DC-coupled high-gain electronic voltage amplifier consisting of differential inputs with a single output. The output of an operation amplifier is managed by negative and positive feedback. The main purpose of negative feedback is to control the magnitude of its output voltage gain while the positive feedback is used in oscillation and regenerative gain. Op-amp is applied in electrical devices which are developed for consumer, scientific, and industrial devices. The op-amp is one example of a differential amplifier which multiplies the difference between two inputs by a single constant factor.

The operation amplifier is applied in analog instrumentation and computation, special transfer functions, special system designs, and signal conditioning in the electrical industry. Op-amps that utilize amps consist of analog assets which are simple and precise. Other types of electronic amplifier are the fully differential amplifier which is the same as the op-amp, but made up of two outputs, the instrumentation amplifier made up of three op-amps, the isolation amplifier and the negative feedback amplifier (Karki, 1998). The amplifier differentials is made up of an input and an output whereby the op-amp amplifies the voltage difference between the two, referred to as the differential input voltage.

The op-amps output voltage is shown by an equation where the non-inverting terminal voltage is equal to the inverting terminal voltage as well as the open-loop gain of the amplifier. It has a very large magnitude which is rarely lower than a million, implying that a small difference, even of a few microvolts, leads to amplifier saturation. This means that the voltage output goes to the extreme end of the maximum or minimum range that is given by the voltage of power supply.  Finley law argues that a situation where the inverting and non-inverting inputs of an operation amplifier are not similar, the end result is in saturation.

In addition, the specific magnitude is not well regulated during the manufacturing process, which means that its impossible to use the op-amp as a stand-alone differential amplifier. When a linear operation is required, the negative feedback must be utilized by applying some of the output into the inverting input. The feedback helps the output of the op-amp to regulate the inputs at an almost equal voltage in order to avoid saturation. Another advantage is that high utilization of negative feedback, the entire circuit is enhanced and other parameters are influenced by the feedback network rather than the operation amplifier itself. When negative feedback is not utilized the op-amp operates as a comparator or a switch. Positive feedback may be used to initialize oscillation or hysteresis (Carter, Brown, 2001).

During ancient times, operation amplifier was basically used in the field of computation to refer to amplifiers that executed different mathematical operations. Nowadays, op-amps are applied in DC and AC amplifiers, Servo Valve Drivers, Deflection Yoke Drivers, Multivibrators, Low Distortion Oscillators, and many others. Modern op-amp is made up of a solid form, high gain, DC voltage amplifier. AC op-amp circuits usually increase the low frequency signals which have not reached the level of conventional amplifiers (0.1 Hz to 20 kHz), when the blocking capacitors of the DC are still operational. In conclusion, at high frequency, both AC and DC op-amp circuits are similar (Carter, Brown, 2001).