🚀 go-pugleaf

Duncan Barclay wrote:
> 
> In article <76kgnq$lin$1@news-1.news.gte.net>,
>         Doug <do@not.spam> writes:
> > Duncan Barclay wrote:
> >> A BJT allows you to control a current by varying the base emitter
> >> voltage.
> >
> > Your claim that the BJT is also a voltage controlled device
> > does work as a model.  No one is denying that.  But, the
> > effect of the voltage on the BJT is to allow current
> > injection to occur.
> 
> Precisely,
>   1) VBE voltage controls current injection at BE juntion
>   2) current injection at the BE junction controls collector current
> 
> Cause and effect....
> 
> > In other words, your voltage source must include current.
> 
> Can't parse that, by definition a voltage source can supply an infinite
> ammount of current, but it does not include it.
---------------------------------------------------
If you can't parse that you need a new parser!! If you put a cap in the
base feed, then the transistor doesn't work no matter the voltage the
base feels, now, does it? This is the difference!! The FET will work,
the BJT won't!! You're being quite silly and pig-headed about this, and
it makes me wonder if this wasn't an ill-addressed "hole" in your
education that is only showing-up now at this late date. Then perhaps
you partied through solid state?
-Steve
 
> > Under the assumption that the BJT is ONLY a voltage device is to say
> > that under a perfect model of a BJT, no current injection is the
> > desired state.  It is not.  Last I saw, BOTH the EM and GP models
> > have current injection forms.  Gee, I wonder why ...
> 
> To get fundemental, all active devices are voltage controlled because
> nature does not provide a current source (no monopoles). BJTs, valves,
> FETs are all govered by electrostatic fields. Remember Schrodinger's
> Equation, or band bending or Laplace's Law or the Boltzmann Transport
> Equation? All the eqautions are of the form
> 
>   [charge_ammount, charge_momentum, charge position] = f(electric field)
> 
> Duncan
-------------------------------
Yes, yes, physics again. I came that way as well, but if you UNDERSTAND
QM and uncertainty then you kNOW the fallacy of cause and effect!!
Especially in electronics!! You wish to:
1) Assert that all current flows BECAUSE of voltage, heuristically
useful but not provable. 
2) You wish to redefine electronic engineering after we have the
definitions standard at that level, you won't win this one, we call
things voltage or current-controlled because it is USEFUL to do so,  
and your way avoids utility with some kind of freshman zeal for
questioning that misses the point entirely, as do most freshmen!

We go by the best linearity-driven cause and effect heuristics for
that one, and you seem to LIKE freshman heuristics, so you really
should LOVE this one, you're just being stubborn because you were
caught in an indefensible statement. Come off it!
-Steve

> Duncan Barclay          | God smiles upon the little children,
> dmlb@ragnet.demon.co.uk | the alcoholics, and the permanently stoned.
-------------------
Perhaps God smiles on the stoned, but they still blow the final exam!!
-Steve
-- 
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