Q1.Which of the following is an invalid state in an 8-4-2-1. Binary Coded Decimal counter
Answer : Option DExplaination / Solution:
In binary coded decimal (BCD) counter the valid states are from 0 to 9 only in binary system 0000 to 1001 only. So, 1100 in decimal it is 12 which is invalid state in BCD counter.
Q2.A 10 kHz even-symmetric square wave is passed through a bandpass filter with centre frequency at 30 kHz and 3 dB passband of 6 kHz. The filter output is
Answer : Option CExplaination / Solution:
10 KHz even symmetric square wave have frequency component present 10KHz, 30KHz, 50KHz, 70KHz
[only odd harmonics due to half wave symmetry]
Since bandpass filter is contered at 30KHz, 30KHz component will pass through
filter output is nearly perfect cosine wave at 10 KHz
Cosine in due to reason that signal in even signal.
Q3.The SOP (sum of products) form of a Boolean function is Σ(0,1,3,7,11), where inputs are A,B,C,D (A is MSB, and D is LSB). The equivalent minimized expression of the function is
Q7.In the following sequential circuit, the initial state (before the first clock pulse) of the circuit is Q1Q0 = 00. The state (Q1Q0), immediately after the 333rd clock pulse is
Q8.A Boolean function f(A,B,C,D) = ∏(1,5,12,15) is to be implemented using an 8×1
multiplexer (A is MSB). The inputs ABC are connected to the select inputs S2S1S0 of the
multiplexer respectively.
Which one of the following options gives the correct inputs to pins 0,1,2,3,4,5,6,7 in order?
Consider the following circuit which uses a 2-to-1 multiplexer as shown in the figure below. The Boolean expression for output F in terms of A and B is
Q10.The current state QAQB of a two JK flip-flop system is 00. Assume that the clock rise-time is much
smaller than the delay of the JK flip-flop. The next state of the system is
Answer : Option CExplaination / Solution:
Total Question/Mark :
Scored Mark :
Mark for Correct Answer : 1
Mark for Wrong Answer : -0.5
Mark for Left Answer : 0