Activity Industry Sector
Information Technology

## Draw The Circuit

### Activity Overview / Details

Now that everyone understands binary numbers, truth tables, and Boolean expressions the fun part comes, wiring the circuit to work; but first we must draw the wiring schematic.  The wiring schematic is derived from the Boolean expression.

(A' * B) + (A * B')

To make an electrical circuit work we must get electricity from the power source (in our circuit the power source is the battery) through the switches and then through the light and back to the battery; so our  schematic must show this path.

Distribute the Light Switch Schematic to each student and explain its meaning.

1.  Since our Boolean expression indicates that there are two ways for the circuit to work there must be two paths to follow from the battery.

2.  The top path and bottom path both go through the A switch first. ( Our drawing is a simplified way of indicating switch contacts since we are not electricians).

3.  The top path goes through the A'  contact then through the B contact.

4.  The bottom path goes throught the A contact then through the B' contact.

5.  Then the two paths come together and go through the light and then back to the battery.

### Materials / Resource

• Light Switch Schematic [ Download ] Schematic For Light Switch Circuit