1. Michael McGrath mam1021@psu.edu 724-456-0657
Simple DC Motor
Michael McGrath

2. Vibrating Pager Motor

3. Design Flow
Transistor
Motor
Digital Logic

4. Digital Logic 74 LS 04 Hex Inverter 14 Pin DIP 6 Individual Gates
Input 0 Output 1
Input 1 Output 0
14 Pin DIP
6 Individual Gates

5. Transistor 2N2222A 3 Pins Base Emitter Collector Collector Base

6. How The Transistor Works
As a switch, needs 5v to turn on.
Using the Transistor as a current Amp
Ice = β * Ibe
If No Tec. Docs safe assumption
β = 100

7. What Value for R?
VCC DC
Motor
Digital
Logic R?

8. Answer = 3.233KΩ R? VCC DC 5V Motor Diode Digital .7V Drop Logic
5V - .7V = 4.3V
V=IR
4.3V / (100 /β) = 4.3/1.33 = 3.233KΩ

9. Prices 74LS04 $0.50 2N2222A $0.25 Resistor Cheap!! Motor $1 - $5
Overall cost < $5

10. Propagation Delay
74LS ns
2N2222A 250 ns

11. Typical Application Transistor DC Motor
Current Amp to drive a motor or other from digital logic device
Can be used as a cheap switch
DC Motor
Pager Vibrator
RC Car Motor
Millions of uses