1. Transistors and Integrated Circuits
ELECTRONICS

2. SYMBOLS NPN Transistor … PNP Transistor ………………….. Integrated Circuit …
Pushbutton …………………………..

3. NPN TRANSISTOR Emitter, Base and Collector (E B C)
When collector is positive, emitter is negative and base is slightly positive.
Large Collector Current (IC) - current flows in the emitter and out of collector
Small Base Current (IB) - current flows in the emitter and out of base

4. PNP Transistor Emitter, Base and Collector (E B C)
When collector is negative, emitter is positive and base is slightly negative.
Large Collector Current (IC) – current flows in the collector and out of the emitter.
Small Base Current (IB) – current flows in the base and out the emitter.

5. INTEGRATED CIRCUITS
Integrated Circuits (ICs) have several components condensed inside very small package:
Transistors
Diodes
Resistors
Etc.
Each IC type performs a different function.
555 IC is used as a clock device.
It provides continuous series of pulses, which can be adjusted in frequency.

6. ALL SYMBOLS