logic circuit definition of logic circuit in the Free Online Encyclopedia.

logic circuit, electric circuit whose output depends upon the input in a way that can be expressed as a function in symbolic logic symbolic logic or mathematical logic, formalized system of deductive logic, employing abstract symbols for the various aspects of natural language.
..... Click the link for more information. ; it has one or more binary inputs (capable of assuming either of two states, e.g., "on" or "off") and a single binary output. Logic circuits that perform particular functions are called gates. Basic logic circuits include the AND gate, the OR gate, and the NOT gate, which perform the logical functions AND, OR, and NOT. Logic circuits can be built from any binary electric or electronic devices, including switches switch, electrical device having two states: on, or closed; and off, or open. Ideally a switch offers a zero impedance to a current when it is closed, and it offers infinite impedance when open.
..... Click the link for more information. , relays relay, electromechanical switch operated by a flow of electricity in one circuit and controlling the flow of electricity in another circuit. A relay consists basically of an electromagnet with a soft iron bar, called an armature, held close to it.
..... Click the link for more information. , electron tubes electron tube, device consisting of a sealed enclosure in which electrons flow between electrodes separated either by a vacuum (in a vacuum tube) or by an ionized gas at low pressure (in a gas tube).
..... Click the link for more information. , solid-state diodes diode (dī`ōd), two-terminal electronic device that permits current flow predominantly in only one direction.
..... Click the link for more information. , and transistors transistor, three-terminal, solid-state electronic device used for amplification and switching. It is the solid-state analog to the triode electron tube ; the transistor has replaced the electron tube for virtually all common applications.
..... Click the link for more information. ; the choice depends upon the application and design requirements. Modern technology has produced integrated logic circuits, modules that perform complex logical functions. A major use of logic circuits is in electronic digital computers. Fluid logic circuits have been developed whose function depends on the flow of a liquid or gas rather than on an electric current.

A circuit that performs some processing or controlling function. Contrast with memory.