matched transistors

[jhaible]

> Paralleling transistors has some possible benefits.  I remember something
> about multiple transistors behaving as follows: the collector currents are
> additive, but the noise of each transistor is uncorrelated, so although
the
> noise from two paralleled transistors is greater than one transistor, it
is
> not doubled, so you gain a little in signal to noise ratio.

Yes.

If memory serves, the data sheet of the LM394 explains it to be many
internal transistors in parallel connection, for that reason.

JH.