# Counters

mcqspedia.com has 56 Question/Answers about Topic Counters

## Why can a synchronous counter operate at a higher frequency than a ripple counter?

- A. The flip-flops change one after the other.
- B. The flip-flops change at the same time.
- C. A synchronous counter cannot operate at higher frequencies.
- D. A ripple counter is faster.
- Correct Answer: Option B

## Synchronous construction reduces the delay time of a counter to the delay of:

- A. all flip-flops and gates
- B. all flip-flops and gates after a 3 count
- C. a single gate
- D. a single flip-flop and a gate
- Correct Answer: Option D

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

- A. The counter can count in either direction, but must continue in that direction once started.
- B. The counter can be reversed, but must be reset before counting in the other direction.
- C. In general, the counter can be reversed at any point in its counting sequence.
- D. The count sequence cannot be reversed, once it has begun, without first resetting the counter to zero.
- Correct Answer: Option C

## The process of designing a synchronous counter that will count in a nonbinary manner is primarily based on:

- A. external logic circuits that decode the various states of the counter to apply the correct logic levels to the J-K inputs
- B. modifying BCD counters to change states on every second input clock pulse
- C. modifying asynchronous counters to change states on every second input clock pulse
- D. elimination of the counter stages and the addition of combinational logic circuits to produce the desired counts
- Correct Answer: Option A

## List the state of each output pin of a 7447 if RBI = 0, LT = 1, A0 = 1, A1 = 0, A2 = 0, and A3 = 1.

- A. RBO = 0, a = 0, b = 0, c = 0, d = 1, e = 1, f = 0, g = 0
- B. RBO = 1, a = 0, b = 0, c = 0, d = 1, e = 1, f = 0, g = 0
- C. RBO = 0, a = 0, b = 0, c = 0, d = 0, e = 1, f = 0, g = 0
- D. RBO = 1, a = 0, b = 0, c = 0, d = 0, e = 1, f = 0, g = 0
- Correct Answer: Option A

## Which segments (by letter) of a seven-segment display need to be active in order to display a digit 6?

- A. b, c, d, e, f, and g
- B. a, c, d, e, f, and g
- C. a, b, c, d, and f
- D. b, c, d, e, and f
- Correct Answer: Option B

## Which segments of a seven-segment display would be required to be active to display the decimal digit 2?

- A. a, b, d, e, and g
- B. a, b, c, d, and g
- C. a, c, d, f, and g
- D. a, b, c, d, e, and f
- Correct Answer: Option A

## A multiplexed display being driven by a logic circuit:

- A. accepts data inputs from one line and passes this data to multiple output lines
- B. accepts data inputs from several lines and allows one of them at a time to pass to the output
- C. accepts data inputs from multiple lines and passes this data to multiple output lines
- D. accepts data inputs from several lines and multiplexes this input data to four BCD lines
- Correct Answer: Option B

## A seven-segment, common-anode LED display is designed for:

- A. all cathodes to be wired together
- B. one common LED
- C. a HIGH to turn off each segment
- D. disorientation of segment modules
- Correct Answer: Option C

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

- A. HIGH
- B. to high impedance
- C. to an open
- D. LOW
- Correct Answer: Option D

## Integrated-circuit counter chips are used in numerous applications including:

- A. timing operations, counting operations, sequencing, and frequency multiplication
- B. timing operations, counting operations, sequencing, and frequency division
- C. timing operations, decoding operations, sequencing, and frequency multiplication
- D. data generation, counting operations, sequencing, and frequency multiplication
- Correct Answer: Option B

## Select the response that best describes the use of the Master Reset on typical 4-bit binary counters.

- A. When MR1 and MR2 are both HIGH, all Qs will be reset to zero.
- B. When MR1 and MR2 are both HIGH, all Qs will be reset to one.
- C. MR1 and MR2 are provided to synchronously reset all four flip-flops.
- D. To enable the count mode, MR1 and MR2 must be held LOW.
- Correct Answer: Option A

## A MOD-16 ripple counter is holding the count 10012. What will the count be after 31 clock pulses?

- A. 10002
- B. 10102
- C. 10112
- D. 11012
- Correct Answer: Option A

## MOD-6 and MOD-12 counters and multiples are most commonly used as:

- A. frequency counters
- B. multiplexed displays
- C. digital clocks
- D. power consumption meters
- Correct Answer: Option C

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

- A. 1 to 12, 11 to 6, 9 to 7
- B. 1 to 12, 12 to 6, 11 to 7
- C. 1 to 12, 9 to 6, 8 to 7
- D. 1 to 12
- Correct Answer: Option D

## What is the difference between a 7490 and a 7493?

- A. 7490 is a MOD-10, 7493 is a MOD-16
- B. 7490 is a MOD-16, 7493 is a MOD-10
- C. 7490 is a MOD-12, 7493 is a MOD-16
- D. 7490 is a MOD-10, 7493 is a MOD-12
- Correct Answer: Option A

## What is the difference between a 7490 and a 7492?

- A. 7490 is a MOD-12, 7492 is a MOD-10
- B. 7490 is a MOD-12, 7492 is a MOD-16
- C. 7490 is a MOD-16, 7492 is a MOD-10
- D. 7490 is a MOD-10, 7492 is a MOD-12
- Correct Answer: Option D

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

- A. HIGH
- B. reset
- C. LOW
- D. preset
- Correct Answer: Option B

## List which pins need to be connected together on a 7493 to make a MOD-12 counter.

- A. 12 to 1, 11 to 3, 9 to 2
- B. 12 to 1, 11 to 3, 12 to 2
- C. 12 to 1, 11 to 3, 8 to 2
- D. 12 to 1, 11 to 3, 1 to 2
- Correct Answer: Option C

## A 22-MHz clock signal is put into a MOD-16 counter. What is the frequency of the Q output of each stage of the counter?

- A. Q1 = 22 MHz, Q2 = 11 MHz, Q3 = 5.5 MHz, Q4 = 2.75 MHz
- B. Q1 = 11 MHz, Q2 = 5.5 MHz, Q3 = 2.75 MHz, Q4 = 1.375 MHz
- C. Q1 = 11 MHz, Q2 = 11 MHz, Q3 = 11 MHz, Q4 = 11 MHz
- D. Q1 = 22 MHz, Q2 = 22 MHz, Q3 = 22 MHz, Q4 = 22 MHz
- Correct Answer: Option B