During the design of BCD to 7 segment decoder, what value is init
| During the design of BCD to 7 segment decoder, what value is initialized to display 9?
A. 5 BH
B. 70 H
C. 73 H
D. 7B H
Please scroll down to see the correct answer and solution guide.
Right Answer is: D
SOLUTION
- In BCD to 7-segment Decoder, the outputs of a digital circuit are often displayed as decimal digits.
- BCD to 7-segment decoder is a combinational circuit that converts a BCD number into signals that are required for the display of the value of that number on a seven-segment display.
Observations:
- The decoder outputs are (a, b, c, d, e, f, g)
- For the display of the digit 0, segments a, b, c, d, e, f will be lit as shown above.
A truth table can be formed for all digits from 0 to 9.
|
Digit |
D |
C |
B |
A |
a |
b |
c |
d |
c |
f |
g |
Hex equivalent |
|
0 |
0 |
0 |
0 |
0 |
1 |
1 |
1 |
1 |
1 |
1 |
0 |
7E |
|
1 |
0 |
0 |
0 |
1 |
0 |
1 |
1 |
0 |
0 |
0 |
0 |
30 |
|
2 |
0 |
0 |
1 |
0 |
1 |
1 |
0 |
1 |
1 |
0 |
1 |
6D |
|
3 |
0 |
0 |
1 |
1 |
1 |
1 |
1 |
1 |
0 |
0 |
1 |
79 |
|
4 |
0 |
1 |
0 |
0 |
0 |
1 |
1 |
0 |
0 |
1 |
1 |
33 |
|
5 |
0 |
1 |
0 |
1 |
1 |
0 |
1 |
1 |
0 |
1 |
1 |
5B |
|
6 |
0 |
1 |
1 |
0 |
1 |
0 |
1 |
1 |
1 |
1 |
1 |
5 F |
|
7 |
0 |
1 |
1 |
1 |
1 |
1 |
1 |
0 |
0 |
0 |
0 |
70 |
|
8 |
1 |
0 |
0 |
0 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
7F |
|
9 |
1 |
0 |
0 |
1 |
1 |
1 |
1 |
1 |
0 |
1 |
1 |
7B |
To display 9, the decoder outputs are \(\underbrace {0111}\) \(\underbrace {1011}\) whose hexadecimal equivalent value is 7BH
