Digital Electronics - Combinational Logic Analysis - Discussion
Discussion Forum : Combinational Logic Analysis - General Questions (Q.No. 9)
9.
A 4-variable AND-OR-Invert circuit produces a 0 at its Y output. Which combination of inputs is correct?
none of the above
Discussion:
12 comments Page 1 of 2.
Naveen said:
6 years ago
1st AND gate input 00 and second AND gate input is 11 and the outputs are 0, 1 this is given to or gate, the output is 1 and is given to invert and output is 0. so answer C is correct.
(1)
Kishor said:
6 years ago
No input combination is specified so each expression gives output 0 for one or other input combination.
AAA said:
8 years ago
Answer C is definitely correct.
A'B'+CD
=00+11
=0+1
=1.
After putting an inverter for 1, it will give us 0 (AND-OR-invert circuit).
A'B'+CD
=00+11
=0+1
=1.
After putting an inverter for 1, it will give us 0 (AND-OR-invert circuit).
Gaurav Chavda said:
9 years ago
All the equation can give 0 output, if we take in input in such a way. Because here no input values are specified/fixed.
Mahendar said:
1 decade ago
Answer C;
From the problem AND and OR inverts is given, so nand and nor.
A'B'=1, CD=0 for nand, then 01 is zero for nor input.
From the problem AND and OR inverts is given, so nand and nor.
A'B'=1, CD=0 for nand, then 01 is zero for nor input.
Jeya said:
1 decade ago
Answer C is correct. Because,
A'B'+CD=Y'=Y.
Take A=1,B=1,C=1 and D=1.
A'=0,B'=0 is connected to AND gate-1, C=1, D=1 is connected to AND gate-2. i.e A'B'=0, CD=1. Outputs of and gate are given to OR gate. i.e 0+1=1. Output is connected to inverter. Hence the output Y=0.
A'B'+CD=Y'=Y.
Take A=1,B=1,C=1 and D=1.
A'=0,B'=0 is connected to AND gate-1, C=1, D=1 is connected to AND gate-2. i.e A'B'=0, CD=1. Outputs of and gate are given to OR gate. i.e 0+1=1. Output is connected to inverter. Hence the output Y=0.
Satish said:
1 decade ago
Take, A=1, B=0, C=1, D=0.
Then we are getting output as 1.
So, answer C is wrong.
Then we are getting output as 1.
So, answer C is wrong.
Dakshesh patel said:
1 decade ago
Take, A=1, B=1, C=1, D=1.
A, B is connected to AND1 GATE. Output is 1. This output is connected to inverter. So output will be 0.
C, D is connected to AND2 GATE. Output is 1. This output is connected to inverter. So output will be 0.
Now this two output is connected to OR GATE. So output is 0.
Therefore answer C is correct.
A, B is connected to AND1 GATE. Output is 1. This output is connected to inverter. So output will be 0.
C, D is connected to AND2 GATE. Output is 1. This output is connected to inverter. So output will be 0.
Now this two output is connected to OR GATE. So output is 0.
Therefore answer C is correct.
Mukund said:
1 decade ago
Without proper values of the variables how can we get the expression.
Himalesh said:
1 decade ago
Take out de swarna`s method.. If input is 1100 output will be 1 after inverted the result.. So we can't determine the answer..
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