How do we use the 4-1 Multiplexer in MultiSim?

[David346]

I have found the 4-1 mux in multisim. However I am unable to use it. I have connected the two inputs, A and B. But what do I connect for the inputs D0, D1, D2, D3?

[Tien_P]

Hi David, 

The pin A and B is used to determine which channel to select and the pin D0 to D3 are your input signals, here is the truth table:

A B Channel out (y)

0 0  D0

1 0  D1

0 1  D2

1 1  D3

[Shank747]

But what do the connections ~G, Y, and ~W represent on the 4:1 MUX?

[Tom__Sedlack]

Y is the output of the selected channel. ~W is the inverted output of the selected channel. ~G is the device enable pin (when low, the part does its thing, when high, the part appears "dead").

If you are not sure if what a component does, Google the datasheet.  It will show what the function of the component and what each pin does.

[Shank747]

Hi Tom

Thank you for the specifications. I'm supposed to use four 2:1 multiplexers to light up a seven-segment display with two 4-bit words are being fed into the multiplexers. I believe i've done all the wiring correctly, but nothing is showing up on the display. What is the A on the multiplexer? Is that the data select input? I have the datasheet for the 2:1 MUX but the labels don't match what is shown for the component in Multisim.

[Tom__Sedlack]

If the pin labels don't match, you can always use the pin numbers to correlate pin functions between the datasheets.  

For your display issue, check the datasheet for the 7448.  When an input has a circle, it usually means that to activate that function, you would need to apply a logic low to the pin.  You have ~LT, ~RBI, and ~BI/RBO all active. 

[Nifaina]

Construct a 4:2 multiplexers from 3 different 2:1 multiplexers.

Now connect the three 2:1 multiplexers in such a way that their output gives the same behaviour as a 4:2 multiplexer. You also should connect both the output from this new multiplexer and the 4:2 multiplexer to the XOR gate .

EXPLAIN how you test the correctness of the component using the output signal.

Can someone help me out with this Question...?