Hello, I'm trying to design a dc voltage amp. with (ideally) 1nV to 1000nV range for a low impedance source. Can you please help me? Which way should I go? Is a zero offset op-amp enough or do I need a discrete stage before? Is there a way to overcome the offset voltage of op-amps? Is there an app note that describes a doable technique of doing this? What topology would you propose? I would appreciate any hints. Thank you! Regards!