Basic information :
The power transistor is a transistor that used in high power amplifier and power supplies. Power transistors are suited for application where a lot of power is being used current and voltage. It is a junction transistor, is designed to handle high current and power and also used in audio and switching circuits.
The power transistor is three terminal semiconductor device used to amplify and switch electronic signals and electrical power. They come in NPN, PNP, and Darlington (NPN or PNP) forms.
The structure and construction of a power transistor are entirely different from that of a single transistor but their characteristics and operation are almost the same.
Power transistors, however, possess controlled characteristics. These are turned on when a current sign is given to base, or control, terminal. The transistor remains in the on-state so long as a control signal is present. When this control signal is removed, a power transistor is totally turned off.
There are four types of power transistor :
- Bipolar junction transistors (BJTs)
- Metal-oxide-semiconductor field-effect transistors (MOSFETs)
- Insulated gate bipolar transistors (IGBTs)
- Static induction transistors (SITs)
How does a power transistor work?
A power transistor can mainly do two different jobs such as work as an amplifier or as a switch. When it works as an amplifier, it takes in a tiny electric current at the input and produces a much bigger electric current at the output.
When it works as switches a tiny electric current flowing through the input of transistor can make a much bigger current flow through the output of transistor.
Why transistor is used in daily life application?
- High voltage gain
- Require low power supply voltage for operation
- Smaller size
- No heating problem during operation
- Solid state device
- Mechanically so strong
- Easily portable
For detailed information
Read more >> Power transistor application