2 To 1 Multiplexer. If s 2 is zero then the output of 2x1 multiplexer will be one of the 4 inputs i 3 to i 0 based on the values of selection lines s 1 s 0. In 2 1 multiplexer there are only two inputs i e a 0 and a 1 1 selection line i e s 0 and single outputs i e y.
Implementation of nand nor xor and xnor gates requires two 2 1 mux. The s 0 signal select signal will pass the a signal if it is low logic 0 or 0v and pass the b signal if it is high logic 1 or 5v or whatever voltage the system uses. Since there are two input signals only two ways are possible to connect the inputs to the outputs so one select is needed to do these operations.
The block diagram and the truth table of the 2 1 multiplexer are given below.
First multiplexer will act as not gate which will provide complemented input to the second multiplexer. D implementation of nand gate using 2. I 0 and i 1 are the two input bits a is the control bit or the select bit and output z. As the name suggests this style of modeling will include primitive gates that are predefined in.
