Multiplexer with TTL IC 74251

Actually you can not bother to design a multiplexer using logic gates because it has many special IC which functioned for a multiplexer.

One of the TTL ICs from the family that you can use to fulfill the function of a multiplexer is IC 74 251. At the IC there are 8 input channels and 3-bit selector and the other lane as a control reset and inverting output. As a note if you are using TTL ICs for your electronic circuit, the voltage supply that is allowed a maximum of 5 volts. So you can be more familiar with the workings of this multiplexer ic, IC74251 consider the truth table below:

C	B	A	G	Y	W
X	X	X	1	Z	Z
0	0	0	0	D0	D0’
0	0	1	0	D1	D1’
0	1	0	0	D2	D2’
0	1	1	0	D3	D3’
1	0	0	0	D4	D4’
1	0	1	0	D5	D5’
1	1	0	0	D6	D6’
1	1	1	0	D7	D7’
Z = High impedance (off)
D0,D1…D7 = Representing the output of the input lines D

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