Op-Amp Integrator circuit design

[verd]

Hey there

This should be nice and simple. Here's the deal-- I was asked to design an Op-Amp Integrator circuit. For a 500Hz square wave input signal that oscillates from +/-0.5v, I was asked to design for a triangle wave output which oscillates from 0 to -5 volts.

I designed the circuit just fine, only problem is that it oscillates from about 0 to 5 volts instead of 0 to -5. I know these circuits have small offsets, so it's not exactly 0 to 5, but close enough. This is a stupid question, but I need a DC offset. I was under the impression that I could just stick a dc voltage source somewhere whose difference would bump the signal down some. But to no avail.

My R is 100 ohms and my C is 1uF-- which works perfectly in PSpice.


Any suggestions?


Thanks!

 

[learningphysics]

Do you need an offset or an inverter? Just wanted to check this since it seems from your description that you need an inverter...