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2.11 BCD to seven segment decoder
A 7-segment display is shown in figure. It has seven flat LEDs arranged in such a way to
display decimal numbers from 0 to 9 and other symbols. The segments are labeled as a, b, c,
d, e, f and g. When LED segments a, b, c, d and g are ON, we get the number 3 as shown in
figure. The display patterns for numbers from0 to 9 are shown in figure.
Figure : 7-segment display showing decimal number 3
Figure : Display pattern for decimal numbers
Figure : Block diagram of BCD to Seven segment decoder
BCD to 7-segment decoder is a logic circuit which converts the BCD (4 bits) code to 7-
segment display code (7 bits). The functional diagram and truth table are shown in figure.
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