Question

What are the invalid inputs in the following flip flop? 

• A. P = 0, Q = 0
• B. P = 0, Q = 1
• C. P = 1, Q = 0
• D. P = 1, Q = 1

Hint:

Always avoid the state where both inputs are 1, as it may lead to an undefined or indeterminate output in flip-flops.

Answer 1

The Correct Option is D

- For most flip-flops, when the inputs P and Q are both set to 1, it creates an invalid state, as it violates the logic of the flip-flop circuit. The outputs are undefined or indeterminate in this state.
- Valid inputs typically follow specific rules to avoid this invalid state. Options (a), (b), and (c) represent valid input combinations.

Conclusion: The invalid input combination for the flip-flop is (d) P = 1, Q = 1.