Digital Logic - Combinational Circuits
1. In which of the following gates, the output is 1, if and only if at least one input is 1?
- Option : C
- Explanation : In OR gate we need atleast one bit to be equal to 1 to generate the output as 1 because OR means any of the condition out of two is equal to 1 which means if atleast one input is 1 then it shows output as 1 . Number of 1's in input may be more than one but the output will always be 1 in OR gate. So the answer is 'C'.
You must be logged in to post a comment.
2. The time required for a gate or inverter to change its state is called
- Option : C
- Explanation :
You must be logged in to post a comment.
You must be logged in to post a comment.
3. The time required for a pulse to change from 10 to 90 percent of its maximum value is called
- Option : A
- Explanation :
You must be logged in to post a comment.
You must be logged in to post a comment.
4. The maximum frequency at which digital data can be applied to gate is called
- Option : A
- Explanation :
You must be logged in to post a comment.
You must be logged in to post a comment.
- Option : C
- Explanation : Y=A+B. This is the equation of OR gate. We require 3 NAND gates to create OR gate. We can also write After 1st NAND operation Y = (A AND B)' Y= A' + B' (Demorgan's Law) After 2nd NAND operation Y= ( A' + B')' Y= A . B (Demorgan's Law) After 3rd NAND operation Y= ( A . B )' Y= A' + B ' (Demorgan's Law) So we need 3 NAND gates.
You must be logged in to post a comment.
You must be logged in to post a comment.
You must be logged in to post a comment.