Question

In order to check the CLR function of a counter ____________

(a) Apply the active level to the CLR input and check all of the Q outputs to see if they are all in their reset state

(b) Ground the CLR input and check to be sure that all of the Q outputs are LOW

(c) Connect the CLR input to Vcc and check to see if all of the Q outputs are HIGH

(d) Connect the CLR to its correct active level while clocking the counter; check to make sure that all of the Q outputs are toggling

The question was asked at a job interview.

Query is from Asynchronous Down Counter topic in section Counters of Digital Circuits

Answer 1

The correct choice is (a) Apply the active level to the CLR input and check all of the Q outputs to see if they are all in their reset state

To explain: CLR stands for clearing or resetting all states of flip-flop. In order to check the CLR function of a counter, apply the active level to the CLR input and check all of the Q outputs to see if they are all in their reset state.