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7 Segment Display- A brief introduction

What is a Seven Segment Display (SSD)?

Seven Segment Display

  • It is an electronic display device for displaying decimal numerals.
  • It is widely used in digital clocks, electronic meters, basic calculators, etc.
  • It is also known as “seven-segment indicator

 

What does it consist of?

  • It consists of 8 LEDs connected in parallel that can be lit in different combinations to display the numbers (0, 1, 2, 3, 4, 5, 7, 8, 9, A, b, C, d, E, F, etc.).
  • Each segment (LED) is denoted by letters A to G.
  • The eighth segment called “Decimal Point” is denoted by DP and is used for the display of non-integer numbers.

 

Segments of a SSD

 

Types of Seven Segment Display and its Internal Connections:

Depending on how the terminals are connected, the SSDs can be classified as:

  • Common Anode Type
  • Common Cathode Type

 

Common Anode                                Common Cathode

 

  • If Anodes of all the 8 LEDs are connected together and all the Cathode are left alone, then we refer to the SSD as “Common Anode Type”.
  • If Cathodes of all the 8 LEDs are connected together and all the Anodes are left alone, then we refer to the SSD as “Common Cathode Type”.

 

 

Output Pins

Output pins of a seven segment display

 

  • It consists of 10 pins, of which 8 pins are connected to LEDs (A, B, C, D, E, F, G, and DP).
  • Depending on the type of the SSD, the two middle pins denoted by COM are either common anodes or common cathodes of all the LEDs.

 

Output Display reference table

A Reference Table for displaying Didigts in seven segment display

Digit

A

B

C

D

E

F

G

0

ON

ON

ON

ON

ON

ON

OFF

1

OFF

ON

ON

OFF

OFF

OFF

OFF

2

ON

ON

OFF

ON

ON

OFF

ON

3

ON

ON

ON

ON

OFF

OFF

ON

4

OFF

ON

ON

OFF

OFF

ON

ON

5

ON

OFF

ON

ON

OFF

ON

ON

6

ON

OFF

ON

ON

ON

ON

ON

7

ON

ON

ON

OFF

OFF

OFF

OFF

8

ON

ON

ON

ON

ON

ON

ON

9

ON

ON

ON

ON

OFF

ON

ON

A

ON

ON

ON

OFF

ON

ON

ON

b

OFF

OFF

ON

ON

ON

ON

ON

C

ON

OFF

OFF

ON

ON

ON

OFF

d

OFF

ON

ON

ON

ON

OFF

ON

E

ON

OFF

OFF

ON

ON

ON

ON

F

ON

OFF

OFF

OFF

ON

ON

ON

 

 

I am a mechanical Engineer.

18 Apr 2019, 14:04