On Jan 9, 2006, at 3:22 AM, Russell McMahon wrote:
>
> In my case it's a "forced Beta" of less than one.

Aside from current amplification, transistors do voltage conversion
as well.  It's gotta be pretty common to operate transistors at
low current betas when driving high voltage loads.  For instance,
I'm working on a "HV" H-bridge for driving EL "stuff" from a micro,
and while I fully expect to drive the bases with the typical 5-10mA
in the base circuit, I expect the HV current to less than that most
of the time.  Even driving a 12V relay with a transistor would
involve very low betas (what; 20-50mA @ 12V from 5-10mA base current?)

BillW

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