Multiplexer :-
It is known as MUX..
Multiplexing is the process of connecting many inputs to one output it is "many into one " process with appropriate logic control signals.
Multiplexer is a basic block or basic logic combinational circuit with
i) 'n' input lines
ii) 'm' control lines / selector lines
iii) one output line 'Y'
It requires OR gate in the O/P.
It cannot be used as a decoder.
Example :- IC 74153,74157
To calculate Select line - Formula :- 2m = n
where, n is the input lines
m is the control lines
4:1 Multiplexer :
Truth table :-
It has 4 input lines (D0 ,D1,D2,D3) two control lines (S1 S0) called select lines and one output line by 'Y'
Working:-
1) When the control word is S1 and S0 is 0 0 then Y = D0
2) When the control word is S1 and S0 is 0 1 then Y = D1
3) When the control word is S1 and S0 is 1 0 then Y = D2
4) When the control word is S1 and S0 is 1 1 then Y = D3
Note that at any instant only one AND is enabled allowing only one data line transmission to the common output line.
It is known as MUX..
Multiplexing is the process of connecting many inputs to one output it is "many into one " process with appropriate logic control signals.
Multiplexer is a basic block or basic logic combinational circuit with
i) 'n' input lines
ii) 'm' control lines / selector lines
iii) one output line 'Y'
It requires OR gate in the O/P.
It cannot be used as a decoder.
Example :- IC 74153,74157
To calculate Select line - Formula :- 2m = n
where, n is the input lines
m is the control lines
4:1 Multiplexer :
Truth table :-
| S1 | S0 | Y = |
| 0 | 0 | D0 |
| 0 | 1 | D1 |
| 1 | 0 | D2 |
| 1 | 1 | D3 |
Working:-
1) When the control word is S1 and S0 is 0 0 then Y = D0
2) When the control word is S1 and S0 is 0 1 then Y = D1
3) When the control word is S1 and S0 is 1 0 then Y = D2
4) When the control word is S1 and S0 is 1 1 then Y = D3
Note that at any instant only one AND is enabled allowing only one data line transmission to the common output line.
