1. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE Computer Technology Transistor to computer gates http://upload.wikimedia.org/wikipedia/commons/4/4e/Diopsis.jpg

2. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE Computer Transistor Central Processor Unit or CPU Motherboard http://upload.wikimedia.org/wikipedia/commons/4/4e/Diopsis.jpg http://en.wikipedia.org/wiki/File:Asus_a8n_VMCSM02.jpg `

3. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE The Transistor Amplifier Remote controlled switch It is the basic element of the computer A modern computer core (CPU) can have over 200,000,000 transistors (200 million). http://www.flickr.com/photos/oskay/2105641530/

4. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE Transistor in digital electronics In modern electronics most transistors are used as a switch that is controlled by an input signal. This is accomplished by giving the transistor a large enough signal to snap it on completely or… giving it a small enough signal to turn it off. Commonly these states (on/off) are represented by a zero (off) or one (on).

5. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE Transistors

6. Transistors: common circuits for computers Transistors are used to form many basic circuits in computers. These are the five basic circuits: Not AND NAND (Not AND) OR NOR (Not OR) They are named after the logic function they provide.

7. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE NOT gate Also called a inverter It inverts the input NOT gate Input AOutput Q 01 10

8. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE Not gate using a NPN transistor NOT gate Input AOutput Q 01 10 If Input A is off then the gate is off and VCC supplies power to the Output Q.

9. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE Not gate using a NPN transistor NOT gate Input AOutput Q 01 10 If Input A is on then the gate is on and Output Q is pulled down to ground.

10. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE Transistor-AND gate The basic AND gate has two inputs If both inputs are high, then the output is high Otherwise the output is low AND gate Input AInput BOutput Q 000 010 100 111

11. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE The AND gate using PNP transistors AND gate Input AInput BOutput Q 000 010 100 111 If Input A or Input B are off then VCC turns on the Q3 and grounds the Output Q. Q3

12. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE The AND gate using PNP transistors AND gate Input AInput BOutput Q 000 010 100 111 If Input A AND Input B are on then Q3 is turned off and Output Q is pulled high. Q3

13. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE Transistor-NAND gate The basic NAND gate has two inputs If any inputs are high, then the output is low Otherwise the output is high NAND gate Input AInput BOutput Q 001 011 101 110

14. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE The NAND gate using PNP transistors NAND gate Input AInput BOutput Q 001 011 101 110 If Input A and Input B are on then Output Q is pulled to ground.

15. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE The NAND gate using PNP transistors NAND gate Input AInput BOutput Q 001 011 101 110 If Input A or Input B are off then Output Q is pulled high.

16. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE Transistor-OR gate The basic OR gate has two inputs If either input is high, then the output is high Otherwise the output is low OR gate Input AInput BOutput Q 000 011 101 111

17. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE Transistor-OR gate with PNPs OR gate Input AInput BOutput Q 000 011 101 111 If Input A or Input B are on then Output Q is pulled high.

18. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE Transistor-OR gate with PNPs OR gate Input AInput BOutput Q 000 011 101 111 If Input A and Input B are OFF then Output Q is pulled low.

19. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE Transistor-NOR gate The basic NOR gate has two inputs If either input is high, then the output is low Otherwise the output is high NOR gate Input AInput BOutput Q 001 010 100 110

20. ©2010 Akula LLC, Jeremy R. Hertzberg, BS CMPE Transistor-NOR gate with PNPs NOR gate Input AInput BOutput Q 001 010 100 110