On Tue, 28 Nov 2000, D Lloyd wrote:

> Hi,
>
> I am currently using the configuration shown to obtain a -ve supply in the
> region of -2.5V, for an LCD. Is there a more optimal solution?
  if -2.5 it's enough it's ok, you don't need zenner
  if you need more, use a npn, in colector a resistor to + ( greater than
5v is better) a doubler bridge ( 2capacitors 2 diodes) conected for -V at
output.
vasile

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