Matt Pobursky said..
> You'll never get more than about 4.4V at the emitter of the transistor,
> since the PIC can only supply ~5V of base drive to the transistor. Use
> a PNP transistor (or P channel FET) with NPN driver stage (or N channel
> FET) to supply the regulator circuit.
>
>
Thanks for the help..but I don't understand why I will only get 4.4v.
I thought that if I supply 5v to the NPN base from a logic high PIC output
pin, the transistor would act as a simple switch and pass the +9v across the
C-E junction.  Why only 4.4v?
Thanks
Les

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