Question 1 |
In a given sequential circuit, initial states are Q_{1}=1 and Q_{2}=0. For a clock frequency of 1 \mathrm{MHz}, the frequency of signal Q_{2} in \mathrm{kHz}, is ____
(rounded off to the nearest integer).

(rounded off to the nearest integer).

200 | |
500 | |
250 | |
750 |
Question 1 Explanation:
\begin{array}{|c|c|c|c|c|}
\hline
Clk & {D}_{\mathbf{1}}=\mathbf{Q}_{\mathbf{2}}[ & D_{\mathbf{2}}=\overline{\mathbf{Q}}_{\mathbf{1}} & {Q}_{\mathbf{1}} & {Q}_{\mathbf{2}} \\
\hline
Initial & & & 1 & 0 \\
\hline
1 & 0 & 0 & 0 & 0 \\
2 & 0 & 1 & 0 & 1 \\
3 & 1 & 1 & 1 & 1 \\
4 & 1 & 0 & 1 & 0 \\
\hline
\end{array}
Therefore, the given counter is having MOD-4
\therefore The frequency of signal Q_{2}=\frac{f_{i}}{4}=\frac{1000}{4} \mathrm{kHz}=250 \mathrm{kHz}
Therefore, the given counter is having MOD-4
\therefore The frequency of signal Q_{2}=\frac{f_{i}}{4}=\frac{1000}{4} \mathrm{kHz}=250 \mathrm{kHz}
Question 2 |
The synchronous sequential circuit shown below works at a clock frequency of 1 \mathrm{GHz}. The throughput, in \mathrm{M} bits/s, and the latency, in ns, respectively, are


1000,3 | |
333.33,1 | |
2000,3 | |
333.33,3 |
Question 2 Explanation:
The given circuit is a type of SISO.
\begin{aligned} \therefore \quad Latency &=n \times T_{\text {clk }} \ldots . .& n= \text{number of flip flops}\\ &=3 \times 1 \quad \ldots . &T_{\mathrm{clk}}=\frac{1}{f_{\mathrm{clk}}}=1 \mathrm{~ns}\\ &=3 \mathrm{~ns} & \end{aligned}
Now,
\begin{aligned} \text{Throughput}&= \text{Number of bits/sec}\\ \because \quad 1 \;bit &=1\; nsec\\ \therefore \quad \text{Throughput} &=10^{9} \mathrm{bits} / \mathrm{sec}\\ &=1000 \mathrm{Mbps} \end{aligned}
\begin{aligned} \therefore \quad Latency &=n \times T_{\text {clk }} \ldots . .& n= \text{number of flip flops}\\ &=3 \times 1 \quad \ldots . &T_{\mathrm{clk}}=\frac{1}{f_{\mathrm{clk}}}=1 \mathrm{~ns}\\ &=3 \mathrm{~ns} & \end{aligned}
Now,
\begin{aligned} \text{Throughput}&= \text{Number of bits/sec}\\ \because \quad 1 \;bit &=1\; nsec\\ \therefore \quad \text{Throughput} &=10^{9} \mathrm{bits} / \mathrm{sec}\\ &=1000 \mathrm{Mbps} \end{aligned}
Question 3 |
A state transition diagram with states A, B, and C, and transition probabilities p_1,p_2,...,p_7 is shown in the figure (e.g., p_1 denotes the probability of transition from
state A to B). For this state diagram, select the statement(s) which is/are universally
true


p_2+p_3=p_5+p_6 | |
p_1+p_3=p_4+p_6 | |
p_1+p_4+p_7=1 | |
p_2+p_5+p_7=1 |
Question 3 Explanation:
\left.\begin{matrix}
A &\rightarrow &A &P_7 \\
A&\rightarrow &B &P_1 \\
A&\rightarrow &C &P_4
\end{matrix}\right\} \Rightarrow P_1+P_4+P_7=1
\left.\begin{matrix} B &\rightarrow &A &P_2 \\ B&\rightarrow &B &P_3 \end{matrix}\right\} \Rightarrow P_2+P_3=1
\left.\begin{matrix} C &\rightarrow &A &P_6 \\ C&\rightarrow &C &P_5 \end{matrix}\right\} \Rightarrow P_5+P_6=1
P_2+P_3=P_5+P_6\Rightarrow Option (A) is correct.
P_1+P_4+P_7=1\Rightarrow Option (C) is correct.
\left.\begin{matrix} B &\rightarrow &A &P_2 \\ B&\rightarrow &B &P_3 \end{matrix}\right\} \Rightarrow P_2+P_3=1
\left.\begin{matrix} C &\rightarrow &A &P_6 \\ C&\rightarrow &C &P_5 \end{matrix}\right\} \Rightarrow P_5+P_6=1
P_2+P_3=P_5+P_6\Rightarrow Option (A) is correct.
P_1+P_4+P_7=1\Rightarrow Option (C) is correct.
Question 4 |
For the circuit shown, the clock frequency is f_o and the duty cycle is 25%. For the
signal at the Q output of the Flip-Flop, _______.


frequency is f_0/4 and duty cycle is 50% | |
frequency is f_0/4 and duty cycle is 25% | |
frequency is f_0/2 and duty cycle is 50% | |
frequency is f_0 and duty cycle is 25% |
Question 4 Explanation:
2-bit counter
\begin{aligned} MSB&&LSB(J,K)\\ 0&&0\\ 0&&1\\ 1&&0\\ 1&&1 \end{aligned}

Duty cycle =50%
Output frequency =f_0/4
\begin{aligned} MSB&&LSB(J,K)\\ 0&&0\\ 0&&1\\ 1&&0\\ 1&&1 \end{aligned}

Duty cycle =50%
Output frequency =f_0/4
Question 5 |
The propagation delay of the exclusive-\text{OR} (\text{XOR})
gate in the circuit in the figure is 3\:ns. The propagation delay of all the flip-flops is assumed to be zero. The clock (\text{Clk})
frequency provided to the circuit is 500\: \text{MHz}.

Starting from the initial value of the flip-flop outputs Q_{2}Q_{1}Q_{0} = 1\;1\;1 with D_{2}=1, the minimum number of triggering clock edges after which the flip-flop outputs Q_{2}Q_{1}Q_{0} becomes 1\; 0\; 0 (in integer) is

Starting from the initial value of the flip-flop outputs Q_{2}Q_{1}Q_{0} = 1\;1\;1 with D_{2}=1, the minimum number of triggering clock edges after which the flip-flop outputs Q_{2}Q_{1}Q_{0} becomes 1\; 0\; 0 (in integer) is
3 | |
4 | |
5 | |
6 |
Question 5 Explanation:

\therefore\quad Total 5 clocks required.
There are 5 questions to complete.