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 |
For the circuit shown below, the propagation delay of each NAND gate is 1 \mathrm{~ns}. The critical path delay, in ns, is ____ (rounded off to the nearest integer).


1 | |
2 | |
3 | |
4 |
Question 2 Explanation:
The given circuit can be drawn as;

\therefore \quad The critical path delay =1 \mathrm{~ns}+1 \mathrm{~ns}=2 \mathrm{~ns}

\therefore \quad The critical path delay =1 \mathrm{~ns}+1 \mathrm{~ns}=2 \mathrm{~ns}
Question 3 |
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 3 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 4 |
In the circuit shown below, P and Q are the inputs. The logical function realized by the circuit shown below is


Y=P Q | |
Y=P+Q | |
Y=\overline{P Q} | |
Y=\overline{P+Q} |
Question 4 Explanation:
\begin{aligned}
\text { Output } & =\bar{Q} \cdot I_{0}+Q \cdot I_{1} \\
& =\bar{Q} \cdot 0+Q \cdot P \\
& =P Q
\end{aligned}
Question 5 |
Consider the circuit shown with an ideal OPAMP. The output voltage V_o is
__________V (rounded off to two decimal places).


0.5 | |
0.75 | |
-0.5 | |
-0.75 |
Question 5 Explanation:

V_A=\frac{V_R}{2} \; and R_{th}=R
V_B=\frac{V_B}{2}

V_C=\frac{(V_R+V_R/4)}{2}=\frac{5}{8}V_R
R_{th}=2R||2R=R
Similarly,
V_D=\frac{V_C}{2}=\frac{5}{16}V_R
So, \frac{S}{16}V_R=\frac{5}{16} \times 1.6V
V_o=\frac{-3R}{(2R+R)} \times \frac{5}{16} \times 1.6=-\frac{3}{2} \times \frac{5}{16} \times 1.6
V_o=-0.5V
There are 5 questions to complete.