Here, we will study **Binary Counter Sequential Circuit** with the help of a set of * questions* and answers. We hope that students who are interested to learn digital electronics and preparing for exams like GATE will find this post useful.

## Binary Counter Sequential Circuit

Here are the questions on the **Binary counter sequential circuit** with their answers.

### What is an asynchronous binary counter?

In a binary counter, if flip-flops do not change states in exact synchronism with the applied clock pulses then the counter is called** **an** asynchronous binary counter. **In this counter, each FF output drives the *CLK *input of the next FF.

### What is a mod-5 counter?

The **mod-5 counter **is a binary counter in which the **mod number **is equal to the number of states that the counter goes through in each complete cycle before it recycles back to its starting state.

### How many states will be there in a mod-5 counter?

There will be **five states** in a mod-5 counter. That means the counter goes through the counting sequence from 000 to 100 in each complete cycle before it recycles back to its starting state.

### What is a glitch in the asynchronous binary counter?

A glitch is an unwanted spike of the voltage appearing at the output waveform of the mod-N asynchronous counter where N<2 ^{n}, Here n=number of flip-flops required to design the counter.

### How do you make an asynchronous counter?

An asynchronous counter can be made by cascading the flip-flops in toggle mode. The clock pulses are applied only to the CLK input of the first flip-flop and then each FF output drives the *CLK *input of the next FF.

### Define the MOD number of any counter.

The **MOD number **of any counter is generally equal to the number of states that the counter goes through in each complete cycle before it recycles back to its starting state.

### How can the mod number of a counter be increased?

The MOD number of a counter can be increased simply by adding more FFs to the counter. To construct any MOD-N counter, we may use the equation** **below** **to find the number of flip-flops (n) required for counter design.

**2 ^{n-1} <= N <=2^{n}**

### An asynchronous counter is often referred to as a **ripple counter** – Why?

An asynchronous counter is often referred to as a **ripple counter** because of the way the FFs respond one after another in a kind of rippling effect.

### A MOD-8 counter is known as a *divide-by-8 counter* – Why?

In a MOD-8 counter, the signal output from the last FF (i.e., the MSB) will have a frequency of 1/8 the input clock frequency; so it is known as a *divide-by-8 counter.*

### A MOD-N counter is known as a *divide-by-N counter* – Why?

In any MOD-N counter, the signal at the output of the last FF (i.e., the MSB) will have a frequency equal to the input clock frequency divided by the MOD – number of the counter. For example, in a MOD-16 counter, the output from the last FF will have a frequency of 1/16 of the input clock frequency. Thus, it can also be called a *divide-by-16 counter.*

## Related posts (for further study) on Binary Counter

**Asynchronous Counter – study & revision notes**

**Synchronous Counter – Study & Revision Notes**

**How to design a Synchronous counter – step by step guide**

**2-bit Synchronous Binary Counter using J-K flip-flops**

**A 3-Bit Asynchronous Binary Counter – Up Counter**

**Asynchronous Up counter for Positive & Negative edge-triggered flip-flops**

**Binary Counter Sequential Circuit – FAQs**

**Frequently Asked Questions on Flip-Flops Sequential Circuit**

**Numerical problems on asynchronous counter & synchronous counter**

**J-K flip-flop – Frequently asked questions for semester & GATE exam**

**Modulus-M (MOD-M) asynchronous counter – Study and revision notes**

**Digital Electronics – Hub page**

**Author of this post**

This post is co-authored by *Professor Saraswati Saha*, who is an assistant professor at RCCIIT, a renowned degree engineering college in India. Professor Saha teaches subjects related to digital electronics & microprocessors.