[sdiy] physical layout of npn and pnp transistors

[patchell]

Jeffrey Pontius wrote:

> (1) Is there a standard in the physical external layout of npn and pnp
> transistors (the 3 legged guys)?
> In particular, are E,B,C always oriented the same relative to the flat
> side of the transistor?  I'd guess E and C would be on opposite sides for
> npn and pnp?

    Transistor packages are equal, regardless of sex.  The arangement of the
Emitter, Base, and Collector are more a function of the particular transistor
type. And even then, watch out.  In my collection of parts, I have 2n3704's
in TO92 packages that are both EBC and ECB pinouts...which sure makes things
really convenient.

>
>
> (2) In some data sheets or packaging of transistors, sometimes there are
> two views of the transistor.  One is from the side - is this viewing the
> flat side of the transistor?  The second view is top or bottom. which is
> it?

    You have to really look at the drawing very carefully.  Hopefully, you
will find a note somewhere that specifies if it is top or bottom view.  There
is no standard.  My guess is though on the side view, in general, you will be
viewing the flat side.  If the lines in the drawing are solid that indicate
the flat, that means you are looking at the flat surface.  If they are dashed
(hidden), you are looking at the round side....

    Hope this helps, some...

>
>
> Thanks, Jeff

--
 -Jim
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