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.
There is a third option that may provide the best performance. That is the LTC6943. If you look on page 10, there is a schematic for a lock-in amplifier. This circuit may perform the other 2. It is hard to say. One key metric of performance for a lock-in amplifier is the integrated noise over its output bandwidth. But there are other metrics. They need to be considered in the context of the application.