MCQ IN COMPUTER SCIENCE & ENGINEERING

Detailed explanation-1: -4x1 Multiplexer has four data inputs I3, I2, I1 & I0, two selection lines s1 & s0 and one output Y. The block diagram of 4x1 Multiplexer is shown in the following figure. One of these 4 inputs will be connected to the output based on the combination of inputs present at these two selection lines.

Detailed explanation-2: -A 4-to-1 multiplexer takes 4 inputs and directs a single selected input to output. The selection of input is controlled by selection inputs. A 4-to-1 multiplexer consists of a 2-to-4 decoder and 4X2 AND-OR. This multiplexer however takes 4 8-bit bus as inputs and outputs a single 8-bit bus.

Detailed explanation-3: -Explanation: The two input multiplexer would have n select lines in 2n. Thus n =1. Therefore, it has 1 select line. Explanation: A combinational circuit that selects one from many inputs is known as Multiplexer.

Detailed explanation-4: -So for a 4-input multiplexer we would therefore require two data select lines as 4-inputs represents 22 data control lines give a circuit with four inputs, I0, I1, I2, I3 and two data select lines A and B as shown.

Detailed explanation-5: -These two control lines can form 4 different combinational logic signals and for each signal one particular input will be selected. So, for instance a 2:1 Multiplexer will have 1 control line because 21 = 2 and a 4:1 Multiplexer will have 2 control lines because 22 = 4.