To produce what you ask, you would need some kind of DC to DC converter or a
charge pump.
Reason, 5+5=10 not 9.
You can look in Digikey or Mouser and find many DC-DC converters, but keep
an eye on output current, and the need for your application.

But if you can work with 9/2  +-4.5VDC then you could use a voltage divider.
Possible way of doing this would be..  Use an opamp voltage follower
(current buffer) circuit with it's input being tied to a voltage divider (2
resistors of equal value tied to +Bat and -Bat)
The output of this would be your reference ground (4.5 volts higher
than -Bat)
+ Bat would be your +4.5
- Bat would be your -4.5

Best regards,
Giles


-----Original Message-----

Hi All...

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

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

Any ideas ?

Thanks
serge.