Why does the arrow in an N-channel mosfet symbol point towards the channel from the substrate?
Logically, I would have thought that because electrons from the substrate move towards the channel to enhance it which would mean the direction of conventional current flow will be from the channel to the substrate.
cheers.
Because the "body" is P-type...
P -> N
Ummmm! Apply some student thought to that idea ;-)
A positive gate voltage (relative to body) does what?
...Jim Thompson
Mine don't.
| | | | |---- | | ------| | | | |->- | | | |
John
That's a crappy symbol, particularly since both drain _and_ source, for an N-channel device, are N-type "plugs".
...Jim Thompson
I couldn't care less how the fet is made. I care about visualizing the circuit it appears in. An SCR has four layers... does your schematic symbol show all four somehow?
I "invented" this symbol because it's more intuitive to me, and because it's easier to resolve on B-size schematics. But I have seen it used elsewhere, including in "equivalent" IC schematics on data sheets.
John
How many layers does an NMOS device have ?;-)
An SCR is a doomsday machine in an ASIC ;-)
...Jim Thompson
Attract minority carriers -- electrons -- from the p-type substrate into the channel under the gate so enhancing it.
=A0 =A0 ...Jim Thompson
=A0 | =A0 =A0mens =A0 =A0 |
=A0 | =A0 =A0 et =A0 =A0 =A0|
=A0|
=A0 =A0 =A0 |
And in linear supplies when before the pass device ...
There ya' go ;-)
...Jim Thompson
Definitely blows fuse _before_ anything else is stressed.
You'd better ;-)
...Jim Thompson
-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at
Do the minority carriers qualify for affirmative action treatment once they made it over into the channel?
Yes. They qualify for wealth redistribution ;-)
...Jim Thompson
So electrons are usually blue?
Leftists electrons are always blue... always think they're entitled to something they haven't yet received.
...Jim Thompson
They must be organizers. Remove the electrons and the atoms are no longer unionized.
Best regards, Spehro Pefhany
Remove the neutrons and you'll have no managers.
same reason the arrow in an NPN transistor points towards the emitter.
Except it doesn't.
John
You've obviously never been taught the mnemonic Never Point iN for NPN.
Jim
The arrow points the way the current (usually) flows.
John
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