A generator for very small direct currents
K D E Crawford · Journal of Scientific Instruments · 1955
Currents from 2 × 10 -17 to 2 × 10 -10 A are generated by applying a linear voltage change, developed by an electronic circuit, to a special output condenser. A source with a resistance greater than 10 16 Ω is thus obtained which makes it particularly suitable for the calibration of current measuring devices and for the measurement of high value resistances.