This blog is for educators, academicians, students and those who are interasted to integrate technology in class room.

Multiplexers

A multiplexer is a circuit which has many inputs but only one output. Multiplexer  or MUX means many into one. By applying proper control signal we can steer any input to the output. Therefor it is also known as data selector and control inputs are called select inputs.

Watch this ppt on Multiplexer

MUXBlockDia gives the general idea of MUX. m control signal can select maximum 2 rest to m input signals and therefore n should be less than or equal to 2 rest to m.

Go through 4-to-1 Multiplexer

Click on this Image for Multiplexer Animation

As shown in the circuit diagram ‘a‘ (or A) and ‘b ‘(or B) are control inputs, A (or D0),B(or D1),C(or D2).D(or D3) are data inputs and Q (or Y) is output.

First end gate will give output of a’b’A(0r A’B’D0), second a’bB(or A’BD1), third ab’C(or AB’D2) and fourth abD(or ABD3) and these output will be given to ‘OR’ which will give output as

Q=a’b’A+a’bB+abC+abD

or

Y=A’B’D0+A’BD1+AB’D2+ABD3

From above equation, suppose control inputs a (or A) =0 and b (or B)=0 then

Q=0’0’A+0’0B+00’C+00D

or

Y=0’0’D0+0’0D1+00’D2+00D3

Therefore Q or Y =1.1D0+1.0D1+0.1D2+0.0D3

Q or Y =D0

Similarly, for control inputs ab or AB =00 the first AND gate to which D0 or A is connected will activate and its output is D0 and all other AND gates are inactive with zero output. Thus Q or Y output with ab or AB=00 will be D0. If D0=0 then output will be zero and if Do=1 output will be 1.

Same way, for ab or AB =01, the Q or Y output will be D1. In a similar manner we get the following truth table


Control Inputa or A                  b  or  B OutputQ or Y
0                               0 Do or A
0                               1 D1 or B
1                               0 D2 or C
1                               1 D3 or D

More clearly go through this ppt

  • Watch video on Multiplexer Based Design.

Combinational Logic-Multiplexer

Summary: Must go through this page of MUX

Assignment:

Q.1    How many control inputs are required for 5-to-1 MUX?

Q.2. Give the type of commercial ICs of multiplexer.

Q.3   Send link of 16-to-1 multiplexer with its output Y equation

and explain its operation in brief.

Q.4   Draw the pinout diagram of 74150 of multiplexer IC and

describe its function with truth table?

Q.5 Can we design multiplexer using OR gates in place of AND and AND gate in place of OR?

Q.5  Go to this link of Multiplexer Applet(on right  top and click on multiplexer) and explain the operation of MUX circuit  with its truth table in excel sheet?

Q.6 Go to this Learning Object of Multiplexer and answer the four questions given in it.

Q.7 Search the link of MUX  tutorial(at least 5 other than used already) and its ICs relevant to our syllabus.

Q.8 Search the ppts and pdf of MUX other than used here.

Q.9 Give links of MUX video and audio relevant to our syllabus.

 

 

Advertisements

Comments on: "Multiplexers" (12)

  1. A.1
    3 control inputs are required for 5-to-1 MUX?

  2. a.2
    7 type of commercial ICs of multiplexer.
    Tyeps of ics
    74157,74158,74153,74352,74151,74151A,74150

  3. a.1
    3 control inputs are required for 5-to-1 MUX?

  4. kamlesh said:

  5. kamlesh said:

  6. kamlesh said:

  7. kuvad hasmukh p. said:

    ans.1 :- 2 control input.

  8. kuvad hasmukh p. said:

    ans.2:

    S.No. IC No. Function Output State
    1 74157 Quad 2:1 mux. Output same as input given
    2 74158 Quad 2:1 mux. Output is inverted input
    3 74153 Dual 4:1 mux. Output same as input
    4 74352 Dual 4:1 mux. Output is inverted input
    5 74151A 8:1 mux. Both outputs available (i.e., complementary outputs)
    6 74151 8:1 mux. Output is inverted input
    7 74150 16:1 mux. Output is inverted input

  9. Ans : 2 control input

  10. A: 7 type of ics : 74157,74158,74153,74352,74151 , 74151A,74150

  11. A multiplexer or mux is a device that select one of several digital input signals and forwards the selected input into a straight line . A mux of 2n input has n select lines, which are used to select which input line send to the output.forwards the selected input into a straight line . A mux of 2n input has n select lines, which are used to select which input line send to the output.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: