This high input impedance circuit was found in American documentation from the 1980s. The power supply must be symmetrical. The circuit applies to modern operational.
This circuit was found in a European documentation from 1964. The circuit makes use of components of...
This circuit consists of a design improvement that we have previously published (1982), obtaining a new...
This adjustable circuit from 0 to 200 nA was found in a 90's EDN. The components can still be...