I want to built a lock-in amplifier with a LO frequency below 5kHz. I am little confused about the choice between AD630 and ADA2200. The performance is the main concern in my application (not the power consumption nor the price). How can I choose the best part: what are the main specifications to look at? And what would be better as a preamplifier: a low noise transimpedance amplifier (such as AD8067, ...) or an input amplifier (such as ADA8429, ...)?
Thank you very much for your answer.