More Related Content Similar to D-Flip-Flops(Digital Logic Design (CS302)) (20) More from MobeenaJavid (6) D-Flip-Flops(Digital Logic Design (CS302))1. Digital Logic Design (CS302)
You are required to design a 4-bit even up-counter using D flip flop by converting combinational
circuit to sequential circuit. The counter will only consider even inputs and the sequence of inputs
will be 0-2-4-6-8-10-0.
4-bit even up-counter using D flip flop
2. 1. Draw the State diagram.
0101
0100
0010
0001
0000
1010
100
1
1000
0111
1101
1011
0011
0110
11111110
3. 2. Generate State & Transition Table.
Q3 Q2 Q1 Q0 Q3 Q2 Q1 Q0 D3 D2 D1 D0
0 0 0 0 0 0 0 1 0 0 0 1
0 0 0 1 0 0 1 0 0 0 1 0
0 0 1 0 0 0 1 1 0 0 1 1
0 0 1 1 0 1 0 0 0 1 0 0
0 1 0 0 0 1 0 1 0 1 0 1
0 1 0 1 0 1 1 0 0 1 1 0
0 1 1 0 0 1 1 1 0 1 1 1
0 1 1 1 1 0 0 0 1 0 0 0
1 0 0 0 1 0 0 1 1 0 0 1
1 0 0 1 1 0 1 0 1 0 1 0
1 0 1 0 1 0 1 1 1 0 1 1
1 0 1 1 1 1 0 0 1 1 0 0
1 1 0 0 1 1 0 1 1 1 0 1
1 1 0 1 1 1 1 0 1 1 1 0
1 1 1 0 1 1 1 1 1 1 1 1
1 1 1 1 0 0 0 0 0 0 0 0
3. Generate simplified Boolean Expression.
D3
Q1 Q0
Q3Q2
00 01 11 10
00 0 0 0 0
Present State Next State D Flip-Flop
4. 01 0 0 1 0
11 1 1 0 1
10 1 1 1 1
3 3 2' 3 0' 3' 2 1 0D Q Q Q Q Q Q Q Q
D2
Q1 Q0
Q3 Q2
00 01 11 10
00 0 0 1 0
01 1 1 0 1
11 1 1 0 1
10 0 0 1 0
2 2 0' 2' 1 0D Q Q Q Q Q
D1
Q1 Q0
Q3 Q2
00 01 11 10
00 0 1 0 1
01 0 1 0 1
11 0 1 0 1
10 0 1 0 1
1 1' 0 1 0' 1 0D Q Q Q Q Q Q
D0
Q1 Q0
Q3 Q2
00 01 11 10
00 1 0 0 1
5. 01 1 0 0 1
11 1 0 0 1
10 1 0 0 1
0 0'D Q
Boolean Expression:
3 3 2 ' 3 0 ' 3' 2 1 0
2 2 0 ' 2 ' 1 0
1 1' 0 1 0 ' 1 0
0 0 '
D Q Q Q Q Q Q Q Q
D Q Q Q Q Q
D Q Q Q Q Q Q
D Q
4. Design the final Circuit diagram.