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Dept. of Mechatronics Engg.

Intro to SSD and BCD to SSD( conversion ) Decoder

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Lab 09

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SSD.

A seven-segment display (SSD), or seven-segment indicator, is a form of electronic display device for displaying decimal numerals that is an alternative to

the more complex dot-matrix displays.

The segments of a 7-segment display are

referred to by the letters A to G, where

the optional DP decimal point 

(an "eighth segment") is used for the display

of non-integer numbers.[2]

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Types of SSD

1- Common Cathode

2- common Anode

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BCD to SSD Decoder/Driver

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TYPE OF BCD to SSD Decoder ICs 74LS48 Common Cathode Active high O/P

74LS47 Common Anode Active low O/P

In common anode attach pin 3,4 5 with the Vcc through 1k resistor ,and inputs to simply with switched

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BCD to SSD Decoder ICs

Lamp Test :LT pin is used to check all LEDs of Seven segment display by Grounding only this pin in common anode configuration.

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BCD to SSD Decoder ICs

RBI/RBOThis pin is used in Ripple Blank input/output Cases .

TASK :1 Construct a digital system using a 74LS47 IC that decodes a BCD number and displays it on a seven- segment display.

NOTE:74LS47 ICs feature active-low outputs designed for driving common-anode LEDs.