Non-invasive AC current sensor and Op Amp


I am rather new to this - but I was wondering what a good approach would be to wire up a Non-invasive AC current sensor ( … Path=84_91) using an Op Amp to get an output voltage range between 0-3.3 volts.

I know that I can use resistors, etc. to convert to a voltage (have found some nice examples), but I have understood that an Op Amp would be a ‘cleaner’ solution, I just am not sure where to start looking for a design …

Could I just use something like the sparkfun board … ts_id=8883 which uses the ACS712 and then pumps it through an op-amp (if I understand correctly) … my concern here is resolution and the 5v requirement of the ACS712 (I only have 3.3v)

anyhow, suggestions, directions where to look, etc. would be much appreciated.

Thanks & kind regards,