As you all know, now a days all the Digital Display’s uses Seven Segment Display. So first of all let’s have a little introduction about Seven Segment Display. How they are fabricated and how their LED’s glow in such a beautiful manner? Seven Segment Display (SSD) is the form of electronic device, used to display decimal numbers. Seven Segment Displays are commonly designed in Hexagonal shape but according to our project’s requirement we can also design them in some other shapes like rectangle, triangle, trapezoid etc. Seven Segment Displays may uses LIQUID CRYSTAL DISPLAY (LCD) or LIGHT EMITTING DIODE (LED) for each display segment. In Seven Segment Display all the positive terminals (Anode) or all the negative terminals (Cathode) are brought together to a common pin and such arrangements are known as “Common Anode” or “Common Cathode” arrangement. In this project we will be using Common Cathode arrangement and Hexagonal shape of Seven Segment Display. A simplest form of Seven Segment Display is shown in the image below:
From the above shown image, we can see that we have total 7 LEDs and we will make them glow in such a scheme that the final image will look like a Numerical number. Now if you recall one of our previous project tutorial which was Sequential LED Blinking using 555 Timer, In that project, we are using a 555 Timer in collaboration with a Shift Register. 555 timer continuously provides clock to the Shift Register and Shift Register gives data to its output pins in parallel manner. In today's project, we are also going to use the same concept. We will use a 555 Timer which will continuously provide clock to Shift Register it will enable it's pin accordingly. We can gather this whole information into a single table and also the sequence in which LED's will blink. Such table is called TRUTH TABLE and it is shown in the image given below:
In the above image, '1' means ON state and '0' means OFF state of a particular LED of Seven Segment Display. Above was a little introduction of Seven Segment Display and now, lets move towards Hardware and see How this beautiful display is actually formed.
You can download the complete simulation of above project by simply clicking on the image given below:
Download Seven Segment Display Project Using 555 Timer
Seven Segment Display Using 555 Timer
- First of all place all the components in your proteus workspace, as shown in the image given below:
- First of all 555 Timer is installed, after that a Shift Register is added. 555 Timer will give clock to the Shift Register. Since we are using common cathode arrangement. So, the 7 input pin of SSD are connected to the output pins of Shift Register and the common cathode pin is connected to circuit's main cathode. If you have placed all the components in their exact positions and all the connections are OK. then, the resultant simulation will look like as shown in the image below:
- Now if you look closely at the upper portion of the image then, you will notice that i have added 2 buttons in the circuit. Left Button in Button # 1 and Right Button is Button # 2.
- If both the Buttons are kept open and when you will run the simulation then, numerical values will start to come on seven segment display. you can also see it in the below image:
- Now the switching of button # 1 includes a very interesting feature. First of all play the simulation and Digits will start to run on Seven Segment Display and at any stage when you will press Button # 1 then Seven segment display will vanish but counting will keep on going in the back. And when you will open the Button#1 again then it will show that digit, up-to which counting have reached. Below is a very interesting feature included:
- During State#1 when Seven Segment Display was showing digit no.2 , we pressed button#1 then, display vanished which can be seen in the state#2. After that when we re-opened the switch#1 then, Seven segment display didn't show the digit no.3 but it shows digit # 8. and this thing can be seen at state#3.
- Now moving forward, the function of switch # 2 is very simple and easy. During simulation running, when we will press the Button # 2 at any instant then, display will immediately stop at that point. So, we can say that this project can also be used as stop watch and button # 2 controls the stop watch. It can also be seen in the image below:
Seven Segments Displays have a large no of applications. Some of them are listed below:
- Digital Clocks.
- Electronic Meters.
- Basic Calculators.
- Electronic Devices to Display Numerical Values. (Generally 14-segments or 16-segments display is used to display full alphanumeric values).
Alright friends, that’s all for today, I hope I have conveyed some knowledge and helped you people in some way. If you have some queries, then ask in comments. Subscribe us via email to get these tutorials straight in your inbox. Till next tutorial, take care and be safe !!! :)
