Help with transistors

[GoodmanMotor]

Hello, i am new to transistors and i would like to ask a general question about what is actually a transistor, how does it function and what are the general specifications of a transistor.
Thank you in advance.

 

[Ratchit]

Hello, i am new to transistors and i would like to ask a general question about what is actually a transistor, how does it function and what are the general specifications of a transistor.
Thank you in advance.

What type of transistor do you have a question about? Did you read or study anything about transistors? We cannot give you a general course on transistors, but we can answer pertinent questions if they are well directed and specific.

Ratch

 

[Miles Prower]

Hello, i am new to transistors and i would like to ask a general question about what is actually a transistor, how does it function and what are the general specifications of a transistor.
Thank you in advance.

There is no such thing as "a" transistor. These come in a whole bunch of varieties: BJT, JFET, MOSFET, VFET, IGBT, SIT and other devices called "transistors" such as the unijunction transistor, programmable unijunction transistor. The latter are control devices that don't amplify.

Then it gets a bit more complicated: the difference between lateral MOSFETs and the vertical MOSFETs.

Some of these are enhancement devices, others depleation devices, and still others can operate both ways. As for specs, these vary considerably, depending on the type involved, whether it's a small signal device or a large signal device.

 

[crutschow]

Here's a basic reference to start.

 

[MrAl]

Hello there,

Very basically transistors are amplifying devices. They take a small signal of some type and amplify it to a larger amplitude version.

Because of their ability to amplify, they also function as switches, being able to switch a larger current with a much smaller current or with a small voltage.
Also because of their ability to amplify they are used in other applications too, but amplification and switching are the most common.
There are other applications that take advantage of the transistors more esoteric characteristics, but these are more rare.

The main specifications are the current through the output circuit and the voltage across the output leads. That limits the usefulness in a given application.
There are other spec's too that come into play such as switching speed, and others that may be important to the application.

Whenever i see someone who wants to understand transistors for the first time i always recommend that they start with the bipolar transistor used as a switching transistor. That allows the person to learn how the basic control of the transistor works.