What is demux (demultiplexer)? ( 2:4 ,3:8 & 4:16 demux )... Q) :- What is demultiplexer ? Ans:- It is a combinational logic circuit which is consist of single input and switches through many many output with the help of select line.. If ' n ' is the no of select line and ' N 'is the no of output line. 1:4 demux :- This demux consist of single data input line band switches through a four data output line with the help of select line. Let us consider ' I ' is input line. S o & S 1 are select line and Y 0, Y 1, Y 2, & Y 3 are output line. Truth table of 1:4 demux. Expression of 1:4 demux. Realisation of 1:4 demux. 1:8 demux This demux consist of single data input line and switches through a eight data output line with the help of select line. Let us consider I is the data input line and S 0, S 1 & S 2, are select line and Y 0, Y 1, Y 2, Y 3, Y 4, Y 5, Y 6 & Y 7 are data outp