rapidly switching polarity of an input signal


I've googled this and I'm either not looking in the right direction or I'm just having trouble finding the info. What I'm interested in doing is creating a square wave to drive a load cell from a digital scale. I want the polarity to switch between +5V and -5V. I feel like this should be easy and I assume I can do it with minimal coding. Ideally I need to control the time the signal is in each state.

What I'm doing is trying to subtract off noise. If I use the noise to be Vn and the input voltage to be +/- dV then I want to know when I'm at a positive voltage and a negative so I can take +V - (-V) where V = dV + Vn and get +V - (-V) = (dV + Vn) - (-dV + Vn) = 2dV.

That will give me a stronger signal and also eliminate some of the noise. I've heard of this being done using a microcontroller but I was wondering if I can make the arduino do it. I haven't done anything with electronics for a few years and used to use a PIC microcontroller a while back so I'm new to the Arduino. Sorry if this sounds confusing or is obvious.

Any help would be greatly appreciated!

look up H-bridge inverter and buy four fet which can supply enough current at 5V for your application.

An Arduino (and a PIC as far as I know) can only produce voltages of 0v or 5v on its output pins. Connecting -5v is almost certain to damage it.

To control negative voltages you need external electronics.