The transistor is an "active" component, a device that uses external power to produce an output signal with more power in it than the input signal. A step-up transformer, a "passive" component has voltage gain but no power gain. What distinguishes devices with power gain is their ability to make oscillators, by feeding some output signal back into the input. The transistor is the essential ingredient of almost every electronic circuit.
|This article is a stub. You can help SDIY wiki by expanding it.|
- ^ The Art of Electronics by Paul Horowitz, Winfield Hill, 2nd ed., Cambridge University Press, 1989, ISBN 978-0-521-37095-0 p.61
- Transistor, Wikipedia