Logic Circuit Synthesis
Synthesizing Switching Functions
Ways to Specify Switching Functions
Note the Connection
Definition of ÒmintermÓ
Note the Connection
Shorthands
These are Equal
Number of Switching Functions
The 16 switching functions of
2 variables
Implication Lattice of
2-variable functions
Logic Synthesis:
Abstraction to Implementation
Logic Synthesis: Stages
Example
Tabulate definition of function
Encode sets into bits
Transcribe the Function to the Encoded Values
Split the Encoded Function
into individual switching functions
The resulting switching functions generally will only be partially specified; some combinations donÕt occur.
As the unspecified values will never occur, we can give the function either value 0 or 1.
Exercise: Òread offÓ the expression for f2.
Exercise: Òread offÓ the expression for f2.
Realize each function by gates
Check by ÒReverse EngineeringÓ
(Try all combinations; one combination is shown)
Rex Program for Checking all Combinations
The Testing Code