Is it Possible to Solve This Problem - Equations and Building Circuits

  • Context: Engineering 
  • Thread starter Thread starter GreenPrint
  • Start date Start date
  • Tags Tags
    Building Circuits
Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
Sign up Log in
2 replies · 2K views
GreenPrint
Messages
1,186
Reaction score
0
# -> means XOR
' => means NOT
AB => means A and B
A+B => means A or B

Is it possible to build the following 3 functions
F=(D#B)+(C#A)
G=DCA'+DB'+CB'A'
H=DC'B+D'C'A+D'BA+C'BA

Using only 4 chips (Build all three functions using only 4 chips not 4 for each function)

I have 8 switches for the inputs and was going to use
Switch 1 for A
Switch 2 for B
Switch 3 for C
Switch 4 for D
Switch 5 for A'
Switch 6 for B'
Switch 7 for C'
Switch 8 for D'

I don't have any other switches. I'm just using a switch and flipping switch 8 to the opposite of switch 4 to get the NOT of D.

I can only use the following chips. At the end of the day there can only be 4 chips on my protoboard so if I use the same chip say twice than this counts as two chips.

7400, 7402, 7404, 7408, 7410, 7411, 7420, 7421, 7425, 7427,
7432, and 7486.

I'm getting that it's not possible and have spent several hours trying to do it. Thanks for any help that you can provide me!
 

Discussion

Physics news on Phys.org
GreenPrint said:
# -> means XOR
' => means NOT
AB => means A and B
A+B => means A or B

Is it possible to build the following 3 functions
F=(D#B)+(C#A)
G=DCA'+DB'+CB'A'
H=DC'B+D'C'A+D'BA+C'BA

Using only 4 chips (Build all three functions using only 4 chips not 4 for each function)

I have 8 switches for the inputs and was going to use
Switch 1 for A
Switch 2 for B
Switch 3 for C
Switch 4 for D
Switch 5 for A'
Switch 6 for B'
Switch 7 for C'
Switch 8 for D'

I don't have any other switches. I'm just using a switch and flipping switch 8 to the opposite of switch 4 to get the NOT of D.

I can only use the following chips. At the end of the day there can only be 4 chips on my protoboard so if I use the same chip say twice than this counts as two chips.

7400, 7402, 7404, 7408, 7410, 7411, 7420, 7421, 7425, 7427,
7432, and 7486.

I'm getting that it's not possible and have spent several hours trying to do it. Thanks for any help that you can provide me!

What is the closest that you've gotten? Can you post what you have tried?
 
GreenPrint said:
I have 8 switches for the inputs and was going to use
Switch 1 for A
Switch 2 for B
Switch 3 for C
Switch 4 for D
Switch 5 for A'
Switch 6 for B'
Switch 7 for C'
Switch 8 for D'
Normally you would use a switch to provide D, and use a gate to generate D'.