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Help me understand and remember the FET symbols

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min2max

min2max

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FET(Field Effect Transistor) is a powerful component. And there are a wide variety of FET's available.

I want to know how all those FET's got their schematic symbols and then get a way of remembering their respective symbols based on a good understanding.

Thanks in advance.
 
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considering junction fets:

for an 'n channel ' JFET ,
imagine that you are forward biasing the gate-to source.
then 'conventional current' will flow from 'gate' to 'source'.
put the direction of the conventional current in 'gate'

thus you get the symbol for 'n-channel JFET'

|---
G --->|
|-- S

for 'p-channel JFET ' you can apply the same and put the direction in 'Gate'

this is how to remember the symbol.

---------- Post added at 15:09 ---------- Previous post was at 15:07 ----------

the symbol in ascii drawing did not come properly in reply.
you can ignore it.
 
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    min2max

    min2max

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Thanks, srizbf. That's helpful in remembering the symbols of JFET's.

Is there any complete material covering such stuff?
 

What I use is invert the G-S arrow , then I read it as a transistor , if the inverted arrow direction is like a NPN then it is a N-mosfet , if the inverted arrow direction is like a PNP then it is a P-mosfet.
You can also treat that inverted arrow as a diode to figure if the gate should have a lower voltage compared to the source (P-mosfet) or the opposite for a N-mosfet.

Alex
 

Thanks, Alex.

Your method is somewhat indirect and a little bit difficult for me to remember (You may feel quite comfortable with it though). Ideally I want to have an intuitive way to remember preferably based on its rationale with which I need not remember anything mechanically.

I hope I'm not the only one who has this need.
 
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Obviously, an in-depth understanding of the rationale of the various types of FET is import and helpful in remembering their circuit symbols. I'll sit down and do some more review and try to figure out a way and report here as long as I think it's worthwhile.

Of course, any kind of inputs are still welcome.
 

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