Thanks Dave and Spehro!

On Sun, Mar 14, 2004 at 02:49:13PM +0000, Dave Dilatush wrote:
> You can simplify the circuit a bit by eliminating Q1 and
> connecting the left end of R3 to the base of Q2.

I see.  So even when the enable signal from the PIC is high, the base of
Q2 is going to be at ~0.6V and the R4/R5 divider will still give a
sensible voltage out.  Thanks.

> Also, put in that 10K base-to-ground resistor Spehro suggested so the
> circuit doesn't turn on due to transistor leakage.

Ah, so the transistors leak if the base is open-circuit?

> I've largely abandoned 7805 voltage regulators for my hobby
> stuff, especially for battery operation.  They waste too much
> current and require several volts of input headroom.  I now use
> the LP2951 low-dropout regulator from National Semiconductor;

Thanks; I'll bear it in mind for future projects.

> HTH a bit...

Very much so, thanks.

Chris

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