operational amplifier

Processor that amplifies the difference between two incoming electrical signals. It is a current gain device. Operational amplifiers have two inputs, an inverting input (−) and a noninverting input (+). The input signal from a sensor or switch, often as part of a potential divider, is compared with a similar signal at the other input. This then decides the type of output. If a positive signal is applied to the noninverting input, the output will be positive. If the input is negative, the output will be negative. If a positive signal is given to the inverting input, the output will be negative. A negative input will give a positive output. If the signals at the two inputs are the same, the output will be zero. Feedback loops are attached from the output to the input in order to control the amplification of the output.

Operational amplifiers usually come in an IC (integrated circuit) package. The output from the amplifier is attached to a transducer driver which in turn activates an output device.

An operational amplifier is an electronic circuit that is used as a basic building block in electronic design. They are used in a wide range of electronic measuring instruments. The name arose because they were originally designed to carry out mathematical operations and solve equations. The voltage gain of an inverting operational amplifier is equal to the ratio of the resistance of the feedback resistor to the resistance of the input resistor.