Synchronous Counter in Digital Logic Device

You may benefited by this slideshow as knowing about the short overview about Synchronous Counters and it's applications. I trying to describe about the topic my simple and easy way. Feel free to ask me any question about this topic. I'll try to help you by my best.

1. Presented By Name- Sonya Akter Rupa ID- 315161009 Batch- 8 th Semester- 5 th Department of CSE Email- [email protected] Hamdard University Bangladesh Thursday, August 3, 2017 Prepered By Sonya Akter Rupa Presentation on Synchronous Counter

2. Outline What is counter ? Types of Counters Why we need counter ? Synchronous Counter & Circuit How to Design a Synchronous Counter 4-bit Synchronous Binary Counter Binary Up-Down Counter Application of Synchronous Counter Thursday, August 3, 2017 Prepered By Sonya Akter Rupa 2

3. What is counter? A counter is a device which stores and sometimes displays the number of times a particular event or process has occurred, often in relationship to a clock signal . A counter is a functional unit with a finite number of states each of which represents a number that can be, upon receipt of an appropriate signal, increased by unity or by a given constant. This device is usually capable of bringing the represented number to a specified value such as zero. Thursday, August 3, 2017 Prepered By Sonya Akter Rupa 3

4. Types of Counters Counters are categorized as: Asynchronous (Ripple) Counters- the flip-flop output serves as a source for triggering other flip-flops. Synchronous Counters- the input pulses are applied to all clock pulse inputs of all flip-flops. The change of a particular flip-flop is dependent CP on the present state of other flip-flops. Thursday, August 3, 2017 Prepered By Sonya Akter Rupa 4

5. Why we need counter? In a digital circuit, counters are used to do three main functions: Timing Sequencing Counting A timing problem might require that a high frequency pulse train, such as the output of a 10MHz crystal oscillator, be divided to produce a pulse train of a much lower frequency, say 1Hz. This application is required to build a precision digital clock. Thursday, August 3, 2017 Prepered By Sonya Akter Rupa 5

6. Why we need counter ? (cont.) A sequencing problem would arise if for instance, it become necessary to apply power to various components of a large machine in a specific order. The starting of a rocket motor is an example of sequencing work or field. Measuring the flow of auto traffic on roadway is an application in which an event must increment a tally. This can be done automatically with an electronic counter triggered by a photocell or road sensor. In this way, the total number of vehicles passing a certain point can be counted. Thursday, August 3, 2017 Prepered By Sonya Akter Rupa 6

7. Synchronous Counter & Circuit In synchronous counter, the external event used to produce a pulse that is synchronized with the internal clock. In synchronous logic circuit, an electronic oscillator generates a repetitive series of equally spaced pulses called the clock signal. The clock signal is applied to all the memory elements in the circuit, called flip-flops. Thursday, August 3, 2017 Prepered By Sonya Akter Rupa 7

8. How to Design a Synchronous Counter Determine desired number of bits and desired counting sequence. Draw the state transition diagram showing all possible states. Use the diagram to create a table listing all PRESENT states and their NEXT states. Add a column for each JK input. Indicate the level required at each J and K in order to produce transition to the NEXT state. Design the logic circuits to generate levels required at each JK input. Implement the final expressions. Thursday, August 3, 2017 Prepered By Sonya Akter Rupa 8

9. 4-bit Synchronous Binary Counter The CP terminals of all flip-flops are connected to a common clock-pulse source. The first stage A0 has its J and K equal to 1 if the counter is enabled . Thursday, August 3, 2017 Prepered By Sonya Akter Rupa 9

10. Binary Up-Down Counter When the up input control is 1, the circuit counts up, since the T inputs are determined from the previous values of the normal outputs in Q. When the down input control is 1, the circuit counts down, since the complement outputs Q’ determine the states of the T inputs. When both the up and down signal are 0’s, the register does not change state but remains in the same count. Thursday, August 3, 2017 Prepered By Sonya Akter Rupa 10

11. Application of Synchronous Counter Synchronous counters are used in lots of designs like Real Time Clock, Processors and so on. The simple application of time counting can be listing as follows: Alarm clock Set an AC timer Set a timer for taking picture in camera Flashing indicator lights of our vehicle Some serious applications can be as follows: Counting the time allotted for a “Process” by the scheduler Counters can be used as clock dividers too We can find their use in common kitchen application as like Microwave Oven and Washing Machines also. Thursday, August 3, 2017 Prepered By Sonya Akter Rupa 11

12. Counter Applications Car Parking Control The counter controls the gate activation for lowering and rising the gate depending on the number of parked cars Each car enters the parking will ascend the counter by one “up” Each car exists the parking will descend the counter by one “down” Thursday, August 3, 2017 Prepered By Sonya Akter Rupa 12

13. Car Parking Control Entrance Sensor Exit Sensor UP Down Interface Gate Activation Display Lower/Rise Available / Full Thursday, August 3, 2017 Prepered By Sonya Akter Rupa 13

14. Reference Books & Websites Digital Logic Design by Morris Mano Digital Logic Design by Brain Holdsworth en.wikipedia.org/wiki/counter_(digital) en.wikipedia.org/wiki/Synchronous-circuit www.quora.com/the-application-of-synchronous-counter Thursday, August 3, 2017 Prepered By Sonya Akter Rupa 14

15. Thursday, August 3, 2017 Prepered By Sonya Akter Rupa