logic circuit

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logic circuit An electric circuit concerned with logic systems. The term logic device is often used synonymously. A logic circuit is required to produce specified binary outputs as a result of specified binary inputs. This may be accomplished by using logic gates, producing what is called hardware circuitry. Alternatively the inputs may be associated with the address lines of a ROM and the outputs with the data lines of a ROM; this is called firmware circuitry.

Hardware circuitry constructed from integrated-circuit packages on circuit boards requires two types of wiring. The first type carries the logic information between gates. The second type provides the power for the individual chips. The process of locating the power paths so that they do not interfere with the logic paths is called power routing.

Logic circuitry may be mathematically analyzed using Boolean (or switching) algebra. In this representation the binary 1 is associated with the identity element and the logic 0 is associated with the null element, i.e. zero.

See also combinational circuit, sequential circuit, digital logic, multivalued logic.