 Good morning. I am Mr. S. S. Shakapure, Assistant Professor, Department of Computer Science and Engineering, Valchan Institute of Technology, Sholabur. Today's my topic for discussion is a digital multiplexer in digital techniques subject. My learning outcome at the end of this session is implementing a Boolean function of any variable with a multiplexer. Now, what is multiplexer? Multiplexer can also called as a max MPX. It's a combinational logic circuit and it switches one of the input from several or we can say the multiple inputs to a single output line using control logic. So, control logics are the select line signals by which we use to switch one of the input from several inputs and the select lines also determines the input is connected to the output. And the multiplexer can also called as a data selector. If you are looking a functional diagram of a multiplexer, of a multiplexer here you can able to see the number of input lines towards your left side of your block diagram and which all these input lines are later connected internally to a single output channel. Here the output channel is also described as a Z and in the bottom side of this block diagram you are able to see the select input channels that channels are like control signals which helps to control or to select the input line or we can say the switching input line to the output line. So, here we have one more line that is a modern stereo system. Modern stereo system which may have switches the music from one of any number of sources. So, the number of sources you can think like that is a cassette tape, CD, radio or you can say the VCR, DVD. So, what is modern stereo system? It is like a multiplexer which switches one of the electronic signal out of this cassette, CD, radio and that switches one of the electronic signal from out of all four resources to sending to the power amplifier or we can say speaker. So, in the next slide we just check it out the application part of this example. So, this is a four multiple resources. So, we have a stereo system or a music system. So, these music systems are multiple resources through the multiplexer we connected all these resources and our control signals AB. If through that select control signals if we are trying to select 00 my MP3 player will send the music to the output channel that is sound system. If you are selecting the control signal 01 then my laptop will be selected and sends the music through laptop to the power that is amplifier. So, in such a way my control signals helps me to switch one of the input to the output line. So, here I have a question that is how many AND gate or gate or XOR gates required for the configuration of full ladder. So, I have the four options out of these four options which one is the correct answer. Just think and ready for the answer my answer is B. So, in the answer B I have the choices to 1 and 2 that is 2 AND gate 1 OR gate and 2 XOR gates. So, even we can able to see the implementation of this full ladder where we can able to see the implementation part. Here I requires 2 OR gates 2 XOR gates and 1 OR gate and 2 AND gate and 2 XOR gate is used for some and 1 OR and 2 AND gates used for writing the carry part. Now, I will continue the multiplexer part multiplexer we can design or we can classify into four different categories or different types. One is two has one multiplexer, four has one multiplexer, eight has one multiplexer, 16 has one multiplexer and for every individual different type the required select lines or control logic signals are different. So, that this decides with the formula 2 to the power N equals to M. If the number of signals R4 the select lines are 2. So, here I have an example 2 as one multiplexer, one select line is control signal and I have a block diagram of this 2 as one multiplexer here, 2 is nothing but 2 input channels D0 and D1 and output we have written as a Y and for each combinational multiplexer circuit we requires a enabled line that is also called as strobe line and the select line is 1 because the number combination of number of select inputs are either 0 or 1 that is that decides with the help of 2 to the power N. So, here the select input is 1. So, 2 to the power 1 is nothing but 2. So, possible combinational inputs are 2. So, the two combinational inputs are either 0 or 1. So, if you are giving the input for control signal as 0 your D0 the input channel will switch from input section to the output section. If you are giving the input signal for control signal as 1 then your D1 channel will be switching from input section to the output section and at the same time your enabled line should be always gates enabled. So, if you are looking my truth table in my previous slide 2 to 1 multiplexer. So, depending on the selector switching the inputs are produced as output that is D0 and D1 and are switched to the output for s equals to 0 and s equals to 1 respectively. The Boolean expression for the output becomes D0 when s equals to 0 and output is D1 when s equals to 1. Now, I have one more example 8 as 1 multiplexer which consisting 3 select lines that is nothing but if as per the formula 2 to the power 3 is nothing but 8. So, you can controls 8 input channels with the help of 3 select control logic. And as usual we have a enabled line and one output section one output line. So, if you are looking the truth table for 8 to 1 multiplexer. So, now in the multiplexer part we have different kind of implementation processes. We can implement different applications with the help of multiplexer. So, now here I have an example to implement a logic circuit using 7 4 1 5 1 IC. This 7 4 1 5 1 IC is nothing but 8 input multiplexer and currently in this example I have to implement some mean terms with the help of our multiplexer problem. So, I have a function a 0 a 1 and a 2 that is I have three different input lines and I have some mean terms in this particular function 1 3 5 6 to implement this problem with the help of 8 input data selector multiplexer. So, first of all I need to write the truth table. So, as usual the given input that is a 0 a 1 a 2. So, for the a 0 a 1 a 2 I can able to write 8 possible inputs they are 0 0 0 0 0 0 1 2 1 1 1 and my outputs for mean term 1 3 5 and 6 is 1 that is mean terms we use to represent with the symbol 1 and for remaining all we use to write 0 is what my truth table. Now, how we can write the solution of my above problem. So, here you can see it has one multiplexer which is very similar like as we seen in the block diagram. So, in the out of 8 input channel we are trying to connect my given all mean terms to the logic 1 line they are 1 3 5 and the remaining one that is 7 and if you are looking logic 0. So, logic 0 we are connected to the remaining all terms which are not available in my given problem. So, as per the logic symbol you will connect all the input channels in the given problem and through the control signal a 0 a 1 a 2 you can select any logic line and that will be switches from your input section to the output section. My summary multiplexers are used in various fields where multiple data needs to be transmitted using a single line like communication system, telephone network, transmission from the computer system of a satellite and these are what my references used to discuss my multiplexer concept. Thank you.