BCD to 7-segment Decoder

• A BCD to 7-segment Decoder generates 7 outputs from a BCD (4-bit) input for driving a 7-segment LED display device to display BCD digits.
• A 7-segment display consists of seven segments designated as a, b, c, d, e, f and g in a clockwise sequence. An optional DP decimal point (an "eighth segment") is used for the display of non-integer numbers.
• In a 7-segment LED display, either all the anodes or all the cathodes of the LEDs in the seven segments are tied together and brought out at a single pin, and the device is accordingly called either a common-anode or a common-cathode display. In this experiment, we will be using a common-cathode display.
• The objective of this experiment is to design, assemble and test a BCD to 7-segment Decoder generating these seven outputs. Note that each segment is lighted when the corresponding decoder output, also denoted by a, b, c, d, e, f and g, is HIGH.

BCD to 7-segment Decoder | A | B | C | D | a | b | c | d | e | f | g | Digit | |---|---|---|---|---|---|---|---|---|---|---|---| | 0 | 0 | 0 | 0 |1 |1 |1 |1 |1 |1 | 0 | 0 | | 0 | 0 | 0 | 1 |0 |1 |1 |0 |0 |0 | 0 | 1 | | 0 | 0 | 1 | 0 |1 |1 |0 |1 |1 |0 | 1 | 2 | | 0 | 0 | 1 | 1 |1 |1 |1 |1 |0 |0 | 1 | 3 | | 0 | 1 | 0 | 0 |0 |1 |1 |0 |0 |1 | 1 | 4 | | 0 | 1 | 0 | 1 |1 |0 |1 |1 |0 |1 | 1 | 5 | | 0 | 1 | 1 | 0 |1 |0 |1 |1 |1 |1 | 1 | 6 | | 0 | 1 | 1 | 1 |1 |1 |1 |0 |0 |0 | 0 | 7 | | 1 | 0 | 0 | 0 |1 |1 |1 |1 |1 |1 | 1 | 8 | | 1 | 0 | 0 | 1 |1 |1 |1 |1 |0 |1 | 1 | 9 |

7 segment display |Digit | Off Segments| |------|-------------| |0 | g | |1 | a,d,e,f,g | |2 |c,f | |3 |e,f | |4 |a,d,e | |5 | b,e | |6 | b | |7 |d,e,f,g | |8 | - | |9 |e |