Multiplexer n n Selects binary information from one

Multiplexer n n “Selects” binary information from one of many input lines and directs it to a single output line. Also know as the “selector” circuit, Selection is controlled by a particular set of inputs lines whose # depends on the # of the data input lines. For a 2 n-to-1 multiplexer, there are 2 n data input lines and n selection lines whose bit combination determines which input is selected. 28 -Feb-21 PJF - 1 Combinational Logic

n A multiplexer is a combinational circuit that receives binary information from one of 2" input data lines and directs it to a single output line. The selection of a particular input data line for the output is determined by a set of selection inputs. A 2"-to-1 multiplexer has 2" input data lines and n input selection lines whose bit combinations determine which input data are selected for the 28 -Feb-21 Chapter 2 -i: Combinational Logic Circuits (2. 1 -- 2. 5) PJF - 2

Multiplexer (cont. ) 28 -Feb-21 PJF - 3 Combinational Logic

2 -to-1 -Line Multiplexer n n Since 2 = 21, n = 1 The single selection variable S has two values: n n S = 0 selects input I 0 S = 1 selects input I 1 The equation: Y = S’ I 0 + SI 1 The circuit: 28 -Feb-21 PJF - 4 Combinational Logic

Example: 4 -to-1 MUX using Cell Library Based Design 28 -Feb-21 PJF - 5 Combinational Logic

END 28 -Feb-21 PJF - 6