
How transistor really works, an alternate viewpoint - dfox
http://amasci.com/amateur/transis.html
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ajdecon
On the one hand, I really like this article in general. It's a pretty clear
explanation of how transistors work physically, without requiring too much
knowledge of semiconductor physics. Though I don't think he introduced the
idea of holes very well.

On the other hand: the whole article is written in a style that suggests this
is some kind of major revelation to someone with a background in electrical
engineering. I really find that hard to believe: is this really never
explained in EE courses? I'm a physics major turned materials scientist, and
this is really well-understood in both of those communities. HN EE's, did you
all never get a course in solid state physics or electronic materials?

Which isn't an insult: I can understand that this kind of understanding might
not be essential to circuit design, though I might think it would help. But if
this is seriously not something they teach EE's, you're missing out. Because
solid state physics is some seriously cool shit.

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borisk
For an electrical engineer transistor is a black box 99.9% of the time. It's
enogh to know it's interface.

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borisk
Interesting stuff, some more info:
<http://en.wikipedia.org/wiki/History_of_the_transistor>

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JoeAltmaier
Not much of a difference - what does it matter where in the circuit you start
tracing current? Why use analogies to water - I dont find it helpful.

Good to distingush between Current and Charge. I likewise like to distinguish
between money and value - which is money over time.

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Daniel_Newby
-1, semantics crank. "Current does not flow."

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ajdecon
Eh, I dunno. He _did_ get really pedantic in that part, but you do run into a
lot of circuit analysis that seems to forget that there are actual charged
particles moving around in there. And that is really helpful to remember when
you want to understand what's going on in detail.

~~~
Daniel_Newby
I'm a big fan of physical insight, but you simply cannot redefine "current" as
"that which does not flow and by implication is stationary".

Better would be to clarify current as charge in the state of motion. Then you
can have your semantic cake and eat it too.

~~~
wbeaty
> cannot simply redefine "current"

Instead, authors of educational articles aimed at the public should stick to
proper usage because it avoids misconceptions. "Flow of charge" is proper,
"flow of current" is not. Unknown to most readers; I'm also using a further
technique to reinforce certain concepts: always avoiding jargon (e.g. don't
hide "charge flow" behind the word "current," instead don't define current at
all. Remove the word entirely, and replace it with "charge flow.") Note that
the intended audience here is little kids and grandmothers. In years of
working with electricity misconceptions among the general public, I find that
"flow of current" is one of the top learning barriers preventing easy grasp of
electricity concepts. It connects to many other mistaken ideas.

Example: "batteries send out current," versus "batteries cause the conductors'
charges to flow."

