1. LOGIC DESIGN AND CIRCUITS SEVEN SEGMENT LED DISPLAY Res. Assist. Hale İnan 1

2. CONTENT  Seven Segment Display  Anode  Cathode  Binary Coded Decimal (BCD)  BCD to Seven Segment Decoder  74LS47  74LS48  N-bit Dip Switch (Slide Style)  Testing Seven Segment Display  Experiment Steps 2

3. Seven Segment Display  Seven segment display contains 8 led.  Seven segment display is used to show some numbers and characters in electric circuits.  Seven segment display has 10 pins.  2 of them are common (Anode or Cathode). Other 8 pin are reserved for the each LED. 3

4. Seven Segment Display 4

5. Seven Segment Display Common Anode  As shown below all the anode segments are connected together.  Power must be applied externally to the the anode connection that is common to all the segments.  Then by applying a ground to a particular segment connection (a-g), the appropriate segment will light up. 5

6. Seven Segment Display Common Anode  The diagram shows that the instance when power is applied to the Common Anode connection and segments b&c are grounded causing these two segments to light up. 6

7. Seven Segment Common Cathode  As shown below all the cathode segments connected together.  For the use of this seven segment, the common cathode connection must be grounded and power must be applied to appropriate segment in order to illuminate that segment. 7

8. Seven Segment Display 8

9. Binary Coded Decimal (BCD)  Binary Coded Decimal (BCD or “8421” BCD) numbers are made up using just 4 data bits (a nibble or half a byte) similar to the Hexadecimal numbers.Hexadecimal  Hexadecimal numbers that range in full from 0 through to F, BCD numbers only range from 0 to 9. 9

10. Binary Coded Decimal (BCD) 10

11. BCD to Seven Segment Decoder  A Digital Decoder IC, is a device which converts one digital format into another.  One of the most commonly used device for doing this is called the Binary Coded Decimal (BCD) to 7-Segment Display Decoder. 11

12. BCD to Seven Segment Decoder 12

13. BCD to Seven Segment Decoder  74LS47 drives the common anode displays.  The terminals BI/RBO and RBI stay disconnected. 13

14. BCD to Seven Segment Decoder 14

15. BCD to Seven Segment Decoder  74LS48 drives the common cathode displays. 15

16. N-bit Dip Switch (Slide Style)  DIP Switches are manual electric switches that are packaged by group into a standard dual in-line package (DIP).  DIP switches are also known as toggle switches, which mean they have two possible positions  on or off. 16

17. Testing Seven Segment Display Step - 1 17

18. Testing Seven Segment Display Step 2 18

19. Testing Seven Segment Display Step 3 19

20. Experiment Steps – Step 1 20

21. Experiment Steps – Step 2 21

22. Experiment Steps – Step 3 22

23. Experiment Steps – Step 4 23

24. Experiment Steps – Step 4 Cont. 24

25. Experiment Steps – Step 4 Cont. 25

26. Experiment Steps – Step 4 Cont. 26

27. Experiment Steps – Step 5 27

28. Experiment Steps – Step 6 28

29. Experiment Steps – Step 7 29

30. Experiment Steps – Step 8 30

31. Experiment Steps – Step 8 Cont. 31

32. Experiment Steps – Step 8 Cont. 32

33. Experiment Steps – Step 8 Cont. 33

34. Experiment Steps – Step 8 Cont. 34

35. Experiment Steps – Step 8 Cont. 35

36. Experiment Steps – Step 8 Cont. 36

37. Experiment Steps – Step 8 Cont. 37

38. Experiment Steps – Step 8 Cont. 38

39. Experiment Steps – Step 8 Cont. 39