mosfet VS power mosfet VS transistor

[electronics-whiz]

To me these words pretty much mean the same thing. Transistor, or heavy duty transistor. How do these devices differ if any compared to each other? Is their a certain place to use a certain one if they are different devices?

[vk6zgo]

To me these words pretty much mean the same thing. Transistor, or heavy duty transistor. How do these devices differ if any compared to each other? Is their a certain place to use a certain one if they are different devices?

Younger people see "mosfet"& automatically think "high power",but this is not the case.
A mosfet is not necessarily a high power device---many mosfets are low power devices used in radio receiver low level RF amplifiers.


Of course,they are all generically,"transistors",but  a "bi-junction" transistor operates in a completely different way to any "FET".
High power devices of either kind are very different to low power ones.

I suggest you look at other people's applications of these devices to get a "feel" for the occasions each device is the more appropriate.

[coppice]

Younger people see "mosfet"& automatically think "high power",but this is not the case.

Really? Isn't most young people's experience of MOSFETs of them being integrated by the billion onto the chips in their phones and computers?

[dannyf]

Transistor

They are all transistors.

, or heavy duty transistor.

There are many small signal mosfets, far more so than small signal bjt.

How do these devices differ if any compared to each other?

Hard to make a generic statement.

Small signal  discrete mosfets tend to be RF types now. Most of them are designed for amplification.

Small signal BJTs are more versatile.

High powered mosfets tend to be for switching: they are faster and more resistant to thermal breakdown than bjts, and have lower switching losses -> up to a point. Beyond which, other devices, like IGBT, SCR/Triac, or plain old transistors take over.

BJTs, even high powered ones, are used more for amplification.

[vk6zgo]

Younger people see "mosfet"& automatically think "high power",but this is not the case.

Really? Isn't most young people's experience of MOSFETs of them being integrated by the billion onto the chips in their phones and computers?

They usually don't know what is inside their "devices"& probably think it is some form of magic!

[wraper]

Younger people see "mosfet"& automatically think "high power",but this is not the case.

Really? Isn't most young people's experience of MOSFETs of them being integrated by the billion onto the chips in their phones and computers?

IMO they read about them as million/billion transistor count in the chip, not as MOSFET. They read about MOSFETS in various motherboard reviews with some description of DC/DC converters on them.

[theoldwizard1]

Power MOSFETs are just designed to handle more current. They are used for turning things that use a lot of power on and off, and in things like class D amplifiers.

MOSFETs are voltage controlled, PNP and NPN transistors are current controlled. For low power, it's better to be voltage controlled.

+1 !

There are some of us who remember when Darlinton transistors were the rage !