peter green wrote:
> note: for the purposes of this discription I will call the transistor
> that handles most of the current the power transistor and the
> transistor that connects to the input the signal transistor.
>
> The problem is that the signal transistor acts as an emmitter
> follower. but it can only do that if it's collector is at a higher
> voltage than it's base.

This is wrong, at least assuming NPN darlington.  In fact, the collector of
the first transistor of a fully on darlington will be a few 100mV lower than
its base.


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