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Combinational circuit

Date: 22 Apr 2015

Combinational circuit is a combination of digital logic chips. Combinational logic is used to build this kind of circuits. The circuits contain boolean operators, inputs and outputs. In a
combinational circuit, output is always based on the given inputs. So the output is a function of inputs and the output is uniquely determined by the values of the inputs at any given time.

combinational circuit block diagram

Block diagram for combinational circuit

A combinational circuit can have several outputs. In that case each output represents a different Boolean function. The circuit may also have many logic gates and inverters but does not have any feedback loop. It is represented by logic diagram. It is described using logic expressions and truth tables.

Examples: Half-adder, full-adder and magnitude comparator.


Combinational circuits are widely used in electronic systems. They are used to carry out arithmetic operations in digital systems such as computers and calculators. They are also used in navigation systems and robots.