2's complementer using mux

[research_vlsi]

2 input xor using mux

Hi friends,

To design 4-bit 2's complementer using minimum number of 2:1 Mux.

I tryed and got a result, First I found the boolean equation's using K'Map. The equations are
If A,B,C,D are inputs and W,X,Y,Z are outputs

W=A xor (B+C+D)
X=B xor (C+D)
Y=C xor D
Z= D

After that I implemented these equation using 2:1 mux, I got 5 mux's.

If any body have solution to reduce the no: of mux.ie, below 5 mux.

Regards...

 

[addn]

mux xor 2:1

hi research_vlsi

can you tell me how to implemented xor use 2:1 mux?

thanks

 

[haneet]

function xor using only 2 to 1 mux

u can design xor by giving the select line of mux as B input of xor and input at '0' pin of mux as A and input at '1' as Abar. Then the complete design is xor using 2:1 mux

 

[addn]

two 2:1 mux = one xor

hi haneet
whether we need two 2:1 mux to implement xor
one for Abar ?

THANKS

 

[haneet]

xor with 2 2:1 mux

hi addn,
yes u would need two 2:1 mux to implement xor and u hav rightly said one is to implement Abar and other one to implement the function.

 

[research_vlsi]

2 to 1 mux xor

Hi addn & haneet

We can implement XOR using one 2:1 mux. I attached a file...

My question is whether we can reduce the no of mux for 4 bit 2's complementer, I got 5 (2:1) Mux....

Thanks and regards..

 

[vinod_g]

implement xor function using three 2:1 muxes

A XOR B = A/B +/AB
SEL LINE==A
FOR 0 INPUT GIVE B;(Abar B when a=0 means Abar we should have B so /A.B)
FOR 1 INPUT GIVE /B (ABbar when a=1 means A we should have /B so A/B)

Added after 12 minutes:



Hi, research_vlsi
I too getting the same 5 mux
1 for generating c+d
2 for generating b+c+d
3 for w
4 for x
5 for y
If u get in another way please inform me

Thanks
Regards...[/quote]

 

[haneet]

xor using 2 to 1 mux

research_vlsi
wht u hav drawn is 1 mux and 1 not gate. but when u implement not gate in mux then it is 1 mux. thus, total no. of mux = "2".
i hope u got it. im attaching the diagram.

 

[research_vlsi]

a xor b with two 2-1 muxes

Hi Mr.Vinod

Ya only 5 mux will be used for that function... It is correct I think so..

Also haneet ur logic also fine...

Thanks & Regards