## Expalin johnson counter, Computer Engineering

Assignment Help:

Write short note on the Johnson counter.

Ans:

Johnson Counter: It is a synchronous counter, where all flip-flops are clocked concurrently and the clock pulses drive the clock input of all the flip-flops together therefore there is no propagation delay. Fig.(a) demonstrates the circuit of Johnson counter. In case of the  D  input  of  FF0  is  driven  by  Q‾ output  of  FF3, that is, the complement of the output of the final flip flop is fed to the D of FF0. Feedback of this arrangement generates the sequence of states illustrated in Table no.1. The 4 bit sequence has a total of 8 states (there is n bit sequence will have 2n states). Therefore an n bit Johnson counter will have a modulus of 2n.

The Q output of all stage feeds the D input of next stage. Although the Q‾ output of the final stage feeds the D input of primary stage. The counter fills up along with 1's from left to right and after that fills up 0s again as demonstrated in Table no.2. Fig. (b) Demonstrates the wave shapes/timing diagram of 4 bit Johnson counter.

Fig.(a) Logic Diagram of Johnson counter

 Clock Pulse Q0 Q1 Q2 Q3 0 0 0 0 0 1 1 0 0 0 2 1 1 0 0 3 1 1 1 0 4 1 1 1 1 5 0 1 1 1 6 0 0 1 1 7 0 0 0 1

Table no.1 Sequence of states of 4 bit Johnson Counter

Fig.(b) Timing Diagram of 4-bit Johnson Counter

#### Higher order predicate logic, Higher Order Predicate Logic : In the v...

Higher Order Predicate Logic : In the very first order predicate logic, we are only allowed to quantify over objects. If we are considered to allow ourselves to quantify over

#### Logical user-centered interactive design methodology, Question: Logical...

Question: Logical User-Centered Interactive Design Methodology is a methodology that identifies six clear stages to help in software development while keeping the user in mind.

#### An 8086 interrupt, An 8086 interrupt can take placedue to the following rea...

An 8086 interrupt can take placedue to the following reasons: 1.  Hardware interrupts caused by some external hardware device. 2.  Software interrupts that can be invoked wit

#### #title.comparator., I want to know basic about it

I want to know basic about it

#### #title.calomel electrode, explain the construction and working of calomel e...

explain the construction and working of calomel electrode

#### Queue, A Queue is a FIFO ( rst in, rst out) data structure. Given the foll...

A Queue is a FIFO ( rst in, rst out) data structure. Given the following queue interface: public interface Queue { int size(); // current queue size boolean isEmpty(); //

#### Design a sample counter, Let's design a synchronous BCD counter. A BCD coun...

Let's design a synchronous BCD counter. A BCD counter follows a sequence of ten states and returns to 0 after count of 9. These counters are also known as decade counters. This typ

#### How to use activex control in .net, How to use ActiveX Control in .Net ? ...

How to use ActiveX Control in .Net ? ActiveX control is a special type of COM component that handles a User Interface. Using ActiveX Control in your .Net Project is even simple

#### Object-oriented program and cell controlled class architectu, Object-Orient...

Object-Oriented Program And Cell Controlled Class Architecture To the variety of scenarios, generic cell control architecture can be applied. An object oriented programming lan

#### Determine flip flop the msi chip is dual edge triggered, The MSI chip 7474 ...

The MSI chip 7474 is ? Ans. MSI chip 7474 is TTL, dual edge triggered D Flip-Flop.

### Write Your Message!

#### Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!