[sdiy] Does Source = Drain???

[David Ingebretsen]

I like Transistor Circuit Techniques Discrete and Integrated by Grant
Ritchie. 

Published by Chapman & Hall/CRC available at Amazon.com both paper and
Kindle, although the Kindle edition formatting is horrible. I would
recommend the paper version.

~~ -----Original Message-----
~~ From: synth-diy-bounces at dropmix.xs4all.nl [mailto:synth-diy-
~~ bounces at dropmix.xs4all.nl] On Behalf Of Ian Fritz
~~ Sent: Sunday, June 13, 2010 11:31 AM
~~ To: John Richetta; Synth DIY
~~ Subject: Re: [sdiy] Does Source = Drain???
~~ 
~~ At 03:54 AM 6/13/2010, John Richetta wrote:
~~ 
~~ >Anyone want to recommend a truly up-to-date and
~~ >complete transistor reference, that is still useful in the context of
~~ >hobbyists dealing with discrete (as well as IC) transistors (as
~~ >opposed to a reference intended just for those designing integrated
~~ >circuits)?  Such texts seem to be almost impossible to find (thus,
~~ >lots of time spent on my part reading a variety of sources, piecing
~~ >little bits together, in a fairly non-authoritative fashion).
~~ 
~~ Horowitz and Hill has a pretty good chapter (Ch 3) on FETs, which
~~ addresses
~~ many of your questions.  That's the place to start for an advanced
~~ hobbyist
~~ level of understanding.
~~ 
~~ As one example, they write: "... FETs ... are nearly symmetrical, but the
~~ gate-drain capacitance is usually designed to be less than the
gate-source
~~ capacitance." (What Antti said.)
~~ 
~~ As far as operating an N-JFET with a positive gate voltage, remember it
is
~~ the gate voltage wrt the more negative of the source or drain voltage
that
~~ defines the gate current.  So if you have AC signals present you have to
~~ look very carefully at what these differential voltages are.
~~ 
~~ In forward bias at limited gate current you will not get much of a field
~~ in
~~ the channel, so you won't get much change in drain-source current.  But
if
~~ you come up with some clever way of getting interesting operation under
~~ these conditions, please let us know!
~~ 
~~ Ian
~~ 
~~ _______________________________________________
~~ Synth-diy mailing list
~~ Synth-diy at dropmix.xs4all.nl
~~ http://dropmix.xs4all.nl/mailman/listinfo/synth-diy