Russell McMahon wrote:
> I have just designed a circuit with a small signal PNP bipolar
> transistor with a forced Beta of about 0.5.
>
> Suggest why?

Basically, your question comes down to "why would I use way more base
current then necessary to saturate the transistor?".

One reason that comes to mind is that the extra base current is just a
byproduct of wanting a low value base resistor to allow for higher switching
speed.  There are also some common base configurations where base current
can exceed collector current over normal operating parameters.

We could sit here and list more, but that seems rather pointless idle
speculation as you've given no information which one of the many reasons
might be the one that actually applied in your case.


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