Original poster: stork <stork@xxxxxxxxxxxxxxxxxxx>
Hi Ed
Even good bipolar opamps have leakage currents below that. 10 nanoamps
is 0.01 uA, a fairly big current.
You're right about bipolar opamps which operate on current. In high
end measurement like this it's best to use fet and mosfet opamps
which use voltage and high impedance on the front ends. Some are in
the high teraohms.