# D Flip Flop

Discussion in 'Homework Help' started by biran, Oct 1, 2008.

1. ### biran Thread Starter New Member

Oct 1, 2008
4
0
Dear sir,
I am having big problem with proving D flip flop equation.
Suppose :
DA=m'n+mA
DB=m'B+mA
Z=B
Sir, How to prove this, with State Table.
I do, about D Flip-Flop single input but here is two input and z output. So, I am really confusing.

2. ### veritas Active Member

Feb 7, 2008
167
0
I'm not quite following your notation for signals. A D flip-flop generally has two inputs: Clock and D, and two outputs: Q and Q'. Can you clarify what your signals mean? A diagram may be useful in helping you out.

3. ### biran Thread Starter New Member

Oct 1, 2008
4
0
Dear sir,
actually im student, i learn allot about D Flip-Flop but collage gave me little bit different type of question. question is:

------------------------------------------------------
A sequential circuit has two D flip flops A and B, two inputs x and y and one output z. flip flops input equations and the circuit output are as follows:
DA=x'y+xA
DB=x'B+xA
Z=B

i) Draw the logic diagram of table.
ii) Tabulate the status table.
-----------------------------------------

4. ### veritas Active Member

Feb 7, 2008
167
0
From that description, I would guess that DA is the D input of flip-flop A and that DB is the D input of flip-flip B.
A and B might then be the respective outputs of the two flip-flops.

Does that jive with what you've been given?

5. ### biran Thread Starter New Member

Oct 1, 2008
4
0

Hello sir,
could you write that truth table.
there is another Z=B

im really confuse !!!

6. ### veritas Active Member

Feb 7, 2008
167
0
You can view the truth table for a D flip-flop here.

You said in your previous post that Z is the output. It is still unclear to me what all of your signals mean, as you have not really clarified that for me. "B" may or may not be the output of one of your flip-flops.

*edit* As I stated before: a block diagram would really help with trying to help you understand your problem.

7. ### biran Thread Starter New Member

Oct 1, 2008
4
0
hello sir,
actually this is a question from university assignment. i am also puzzle so im begging help.

8. ### beenthere Retired Moderator

Apr 20, 2004
15,815
282
You have not provided enough material for us to help with. We don't know enough about the problem. I suspect if you can get the logic diagram made up, you will also be able to see the answer.

9. ### malu New Member

Oct 14, 2008
1
0
Dear sir,
actually im student, i learn allot about D Flip-Flop but collage gave me little bit different type of question. question is:

------------------------------------------------------
A sequential circuit has two D flip flops A and B, two inputs x and y and one output z. flip flops input equations and the circuit output are as follows:
DA=x'y+xA
DB=x'B+xA
Z=B

i) Draw the logic diagram of table.
ii) Tabulate the status table.
-----------------------------------------

10. ### beenthere Retired Moderator

Apr 20, 2004
15,815
282
Could either of you explain the similarity of these questions? Brian? Malu?

11. ### kasturi New Member

Apr 16, 2009
1
0
Could either of you explain the similarity of these questions? Kasturi?