Sequential Circuits - Flip Flops - 15

+2 votes

image

Which of the following pattern is detected by the above circuit?

(A) It detects if a string has three or more consecutive ones

(B) It detects  if a string has four or more consecutive ones

(C) It detects  if a string has two or more consecutive ones

(D) It detects if a  string has a pattern 1010

asked May 19 in Digital by gbmentor (14,290 points)
reshown May 20 by gbmentor

4 Answers

+2 votes
 
Best answer

Please go through the explanation...

answered May 21 by getgatebook (25,670 points)
When BA is 00 and y is 0 o/p is 1. So ans should be C.Why A?
why o/p is 1 ?  can you elaborate it .
Sorry BA is 11 and y is 0 then o/p is 1.. so it also detects two ones,right?
0 votes
A is correct one
answered May 20 by tsnikhilsharmagate2018 (17,270 points)
+1 vote
@getgatebook

Please provide explanation for this question.
answered May 20 by tskushagra-guptacse (10,800 points)
Sure. We will do it by tomorrow.
Sir there are many questions which need your explanation.
please try to explain necessarily those questions which are not yet marked as best answer.
–2 votes
just concentrate on first ff y=1 and let all others be 0 so first flip flop will propogate 0

now if A=0 then A'=1 and second gate for second flip flop will be on so it will now propogate 1

this was first y=1

from now on first ff will easily propogate 1 and same is for second because of upper and gate of both will always be high now see the inputs of last and gate it will get on after second pass

 

so it can detect 2 or more sequence of 1

answer is "c"
answered Jun 2 by tarunpro20 (170 points)
Answer:
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