Mixed Logic Combinational Circuits
|
Truth |
‘1’ |
‘0’ |
|
False |
‘0’ |
‘1’ |
|
|
- active high |
- active low |
|
|
- positive logic |
- negative logic |
If mixed logic is used then notation is needed for keeping track which variable is active high and which variable is active low.
A.H
ß vabiable A is active high
B.L ß variable B is active low
Logic Symbols
|
X.H |
Y.H |
O.L |
|
0 |
0 |
1 |
|
0 |
1 |
1 |
|
1 |
0 |
1 |
|
1 |
1 |
1 |
|
X.H |
Y.L |
O.H |
|
0 |
0 |
0 |
|
0 |
1 |
0 |
|
1 |
0 |
1 |
|
1 |
1 |
0 |
|
X.L |
Y.L |
O.H |
|
0 |
0 |
1 |
|
0 |
1 |
0 |
|
1 |
0 |
0 |
|
1 |
1 |
0 |
