doubt

Question

Answer 1

Find the equation of Next State, Q_n = D (from D F-F) = Q.X' + Q'.Y (here Q is previous state)

If we draw the characteristics table of Y X Q to find Qn using the above equation:

Y X Q  Qn

0 0 0  0

0 0 1  1

0 1 0  0

0 1 1  0

1 0 0  1

1 0 1  1

1 1 0  1

1 1 1  0 

(YX->Qn) : (00-latch mode, 01-reset mode, 10-set mode, 11-toggle mode)

So, It is J K Flip-flop with J=Y and K=X.

Answer is D.

Answer 2

State Equation of given Diagram is Q(t+1) =Q.X' + Q'.Y 

and  State Equation of J-K FlipFlop is Q(t+1) =Q.K' + Q'.J 

Comparing both equation we get X=K and Y=J

hence d)