Serge Marchal wrote:

> Hi All...
>
> I need for a project to convert from a 9V battery
> to a +5 -5 voltage, and consume the least current

Well, how much current does your load require?
(At +/- 5 volts?)

> My  question is:
> Should I use a regulator and how can I generate a negative voltage
> from a regulator

Does you load REQUIRE regulated voltage?
A regulator does not generate voltage, it REGULATES an unregulated
source.

You need a switching converter.
For low currents a capacitive converter is sufficient.
For higher currents an inductive element is required.
Losses in the converter will be reflected as additional current demand
on the 9 volt supply.

> Any ideas ?
>
> Thanks
> serge.

--
Thomas C. Sefranek  WA1RHP
ARRL Instructor, Technical Specialist, VE Contact.
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