In the circuit shown below, a positive edge-triggered D Flip-Flop is used for sampling input
data Din using clock CK. The XOR gate outputs 3.3 volts for logic HIGH and 0 volts for
logic LOW levels. The data bit and clock periods are equal and the value of $${{\Delta T} \over {{T_{CK}}}}$$ = 0.15,
where the parameters $$\Delta T$$ and TCK are shown in the figure. Assume that the Flip-Flop and the
XOR gate are ideal.
If the probability of input data bit (Din) transition in each clock period is 0.3, the average
value (in volts, accurate to two decimal places) of the voltage at node X, is _______.
Your input ____
2
GATE ECE 2018
MCQ (Single Correct Answer)
+2
-0.67
A 2 $$ \times $$ 2 ROM array is built with the help of diodes as shown in the circuit below. Here W0
and W1 are signals that select the word lines and B0 and B1 are signals that are output of the
sense amps based on the stored data corresponding to the bit lines during the read operation.
During the read operation, the selected word line goes high and the other word line is in a
high impedance state. As per the implementation shown in the circuit diagram above, what
are the bits corresponding to Dij (where i = 0 or 1 and j = 0 or 1) stored in the ROM?
A four-variable Boolean function is realized using
4 $$ \times $$ 1
multiplexers as shown in the
figure.
The minimized expression for F(U, V, W, X)
is
A
$$\left( {UV + \overline U \overline V } \right)\overline W $$
B
$$\left( {UV + \overline U \overline V } \right)\left( {\overline W \overline X + \overline W X} \right)$$
C
$$\left( {U\overline V + \overline U V} \right)\overline W $$
D
$$\left( {U\overline V + \overline U V} \right)\left( {\overline W \overline X + \overline W X} \right)$$
4
GATE ECE 2018
MCQ (Single Correct Answer)
+1
-0.33
A function F(A, B, C) defined by three Boolean variables A, B and C when expressed as sum
of products is given by
F = $$\overline A .\overline B .\overline C + \overline A .B.\overline C + A.\overline B .\overline C $$
where, $$\overline A $$, $$\overline B $$, and $$\overline C $$ are the complements of the respective variables. The product of sums
(POS) form of the function F is
A
F = (A + B + C)(A + $$\overline B $$ + C)($$\overline A $$ + B + C)
B
F = ($$\overline A $$ + $$\overline B $$ + $$\overline C $$)($$\overline A $$ + B + $$\overline C $$)(A + $$\overline B $$ + $$\overline C $$)
C
F = (A + B + $$\overline C $$)(A + $$\overline B $$ + $$\overline C $$)($$\overline A $$ + B + $$\overline C $$)($$\overline A $$ + $$\overline B $$ + C)($$\overline A $$ + $$\overline B $$ + $$\overline C $$)
D
F = ($$\overline A $$ + $$\overline B $$ + C)($$\overline A $$ + B + C)(A + $$\overline B $$ + C)(A + B + $$\overline C $$)(A + B + C)