### Presentation_3

```LOGIC DESIGN AND CIRCUITS
SEVEN SEGMENT LED DISPLAY
Res. Assist. Hale İnan
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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
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

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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.




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Seven Segment Display
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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.



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Seven Segment Display Common Anode

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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.
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.


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Seven Segment Display
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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)
Hexadecimal numbers that range in full from 0 through
to F, BCD numbers only range from 0 to 9.


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Binary Coded Decimal (BCD)
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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.
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BCD to Seven Segment Decoder
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BCD to Seven Segment Decoder


74LS47 drives the common anode displays.
The terminals BI/RBO and RBI stay disconnected.
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BCD to Seven Segment Decoder
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BCD to Seven Segment Decoder

74LS48 drives the common cathode displays.
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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.
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Testing Seven Segment Display Step - 1
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Testing Seven Segment Display Step 2
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Testing Seven Segment Display Step 3
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Experiment Steps – Step 1
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Experiment Steps – Step 2
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Experiment Steps – Step 3
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Experiment Steps – Step 4
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Experiment Steps – Step 4 Cont.
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Experiment Steps – Step 4 Cont.
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Experiment Steps – Step 4 Cont.
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Experiment Steps – Step 5
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Experiment Steps – Step 6
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Experiment Steps – Step 7
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Experiment Steps – Step 8
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Experiment Steps – Step 8 Cont.
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Experiment Steps – Step 8 Cont.
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Experiment Steps – Step 8 Cont.
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Experiment Steps – Step 8 Cont.
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Experiment Steps – Step 8 Cont.
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Experiment Steps – Step 8 Cont.
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Experiment Steps – Step 8 Cont.
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Experiment Steps – Step 8 Cont.
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Experiment Steps – Step 8 Cont.
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```