Hi all:

 I am trying to compare bipolar,  FET and Mosfet transistors
Could be said that the FET and MOSFET are transistors of a greater
amplification capacity than the bipolar but they carry out the same one
function that is to amplify?
 In various circuits they seem to be used for the same functions that
the bipolar 
Thanks in advance for any comment

"chriswilliams" <c...@yahoo.com> wrote in message
news:1...@h48g2000cwc.googlegroups.com...
> Hi all:
>
>  I am trying to compare bipolar,  FET and Mosfet transistors
> Could be said that the FET and MOSFET are transistors of a greater
> amplification capacity than the bipolar but they carry out the same one
> function that is to amplify?
>  In various circuits they seem to be used for the same functions that
> the bipolar
> Thanks in advance for any comment
>

Take a peek inside your computer and you'll see many MOSFET that are used as
switches.  Study upon how the characteristics of the various structures
differ.
Relate the advantages and disadvantages of each.

"chriswilliams" <c...@yahoo.com> wrote in message
news:1...@h48g2000cwc.googlegroups.com...
> Hi all:
>
>  I am trying to compare bipolar,  FET and Mosfet transistors
> Could be said that the FET and MOSFET are transistors of a greater
> amplification capacity than the bipolar but they carry out the same one
> function that is to amplify?
>  In various circuits they seem to be used for the same functions that
> the bipolar
> Thanks in advance for any comment
>

Hello Chris, to put it simply, a bi-polar transistor is current driven i.e
The output is dependent on the current into the base, while a FET or MOSFET
are voltage driven and the output depends on the voltage applied to the
gate. The gates of FETs and MOSFETS are essentially capacitors and virtually
no current flows after the gate capacitance has been charged.
All three can be used as amplifiers or switches.

... Johnny

chriswilliams wrote:

> Hi all:
> 
>  I am trying to compare bipolar,  FET and Mosfet transistors
> Could be said that the FET and MOSFET are transistors of a greater
> amplification capacity than the bipolar but they carry out the same one
> function that is to amplify?
>  In various circuits they seem to be used for the same functions that
> the bipolar 
> Thanks in advance for any comment
> 
bipolar are current controlled devices, where is the fets are voltage
controlled devices.


-- 
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5