Programmable Logic Device MCQs

Question 1

A counter with a modulus of 16 acts as a ________.

Accepted Answer

divide-by-16 counter

Answer

divide-by-8 counter

Answer

divide-by-32 counter

Answer

divide-by-64 counter

Question 2

What is the difference between a 7490 and a 7493?

Accepted Answer

7490 is a MOD-10, 7493 is a MOD-16

Answer

7490 is a MOD-16, 7493 is a MOD-10

Answer

7490 is a MOD-12, 7493 is a MOD-16

Answer

7490 is a MOD-10, 7493 is a MOD-12

Question 3

A 4-bit counter has a maximum modulus of ________.

Accepted Answer

16

Answer

3

Answer

6

Answer

8

Question 4

Which of the following statements best describes the operation of a synchronous up-/down-counter?

Accepted Answer

In general, the counter can be reversed at any point in its counting sequence.

Answer

The counter can count in either direction, but must continue in that direction once started.

Answer

The counter can be reversed, but must be reset before counting in the other direction.

Answer

The count sequence cannot be reversed, once it has begun, without first resetting the counter to zero.

Question 5

The parallel outputs of a counter circuit represent the:

Accepted Answer

clock count

Answer

parallel data word

Answer

clock frequency

Answer

counter modulus

Question 6

Any divide-by-N counter can be formed by using external gating to ________ at a predetermined number.

Accepted Answer

reset

Answer

HIGH

Answer

LOW

Answer

preset

Question 7

How many natural states will there be in a 4-bit ripple counter?

Accepted Answer

16

Answer

4

Answer

8

Answer

32

Question 8

List which pins need to be connected together on a 7492 to make a MOD-12 counter.

Accepted Answer

1 to 12

Answer

1 to 12, 11 to 6, 9 to 7

Answer

1 to 12, 12 to 6, 11 to 7

Answer

1 to 12, 9 to 6, 8 to 7

Question 9

A principle regarding most display decoders is that when the correct input is present, the related output will switch:

Accepted Answer

LOW

Answer

HIGH

Answer

to high impedance

Answer

to an open