what is the meant by negative voltage

[chandu.kurapati]

Hi every one,
I know that voltage is the potential difference between the two points, for operating one system we are providing some digital voltage like 12v,9v etc.. depends on the application which is reference to the ground, but at some place i am read about negative voltage -5v, what is the importance of the negative voltage and what is the reference for the negative voltage, is there negative voltage is required to operate the system.

like that positive voltage we also operate the system with negative voltage,is it possible?

 

[Allen6502]

Imagine the 12V, 9V and 5V are batteries. If the 12V and 9V batteries have their negative ends connected to Ground (Ref point) and the positive ends would give you +12V and +9V. If you connect the positive end of the 5V battery to Ground, then the other end of the battery would give you -5V.

The negative voltage are commonly used in op-amps and some very old types of DRAM. I think PC motherboard are still having -5V and -12V on the power supply or may be only in older MBs.

Allen

 

[chandu.kurapati]

Hi,
Thank you allen6502, i understand the importance of the negative voltage in the system.

Thanks & Regards,
Chandu.Kurapati.