Transistors
A A device that amplifies an electronic signal made of three layers of semi-conductive material. is a A material that has an electrical conductivity value falling between that of a conductor and an insulator. that amplifies a signal from a sensor - it is like a small electronic switch. Transistors have three legs, A connection on a transistor, when a small voltage passes through the base a larger voltage follows through the other two legs., A connection on a transistor, allowing a large voltage to flow through to the emitter when triggered by the base. and A connection on a transistor, voltage exits at the emitter after entering at the collector..
By combining transistors with input devices which increase or decrease the voltage between the base and emitter, an output device can be automatically turned on or off.
When a small The potential difference across a cell, electrical supply or electrical component. It is measured in volts (V). at the base connection is detected, the transistor is switched on and a large Moving electric charges, eg electrons moving through a metal wire. can flow in through the collector and out through the emitter.
Advantages
- inexpensive way of improving the sensitivity of a circuit
- can be made a very small size to reduce the size of a circuit
Disadvantages
- sensitive to heat and can be damaged during soldering
