1. COMBINATIONAL LOGIC Circuit Design

2. Steps Create the truth table
Extract the Boolean Expression from the truth table or create a K-Map
Simplify the expression
Draw the schematic
Build the circuit

3. Logic Problem
Design a safety alarm system for a car that alerts the driver when the seatbelts have not been fastened, or when the door is ajar while the key is in the ignition.
A=Key B=Door C=Seatbelt
A B C X
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
Boolean Expression Is:
ABC + ABC + ABC=X 1
ABC 1
ABC 1
ABC

4. Create Expression & Simplify
K-Map
Boolean Simplification C 1 AB 00
Dist. 01
Th. 6 11 1 1
Th. 4
Dist. 10 1
Th. 11
Dist.

5. Create Circuit SchematicX

6. NAND Only Solution

7. CircuitMaker Demo