RE: SMALL CURTIS AS TRANSIS

[eric.chang@chrysalis.org]

Hi Rob.  I have heard that MOSFET's are easier to parallel.  There is
an excellent and very comprehensive treatment of paralleling in the Motorola
MOSFET reference manual.  Parts of this may be
available on the WWW.  You should be able to
find this by searching their site.  
Obilgatory information content:  The reason that it is possible
to parallel MOSFET's is that thety have a negative thermal
coefficient of RdsOn.  But, as many are eager to point out, this
does not buy you as much as one would think, due to the relatively
weak dependence.  You could still get one that is out of line.
Again, the Motorola article has some statistical data which is helpful.  It is
useful to do some matching.  I can't remember what the outlier is out of a lot
of
100, but it is something like 30%.
 
Eric