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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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