Use of a 100 M(OMEGA) Step Hamon Resistor for Calibration of Pico-Ammeters in DC Current in the Range (100 pA)/(100 nA)

摘要

This paper describes a measurement circuit for the calibration of pico-ammeters in dc current. The system is based on a 100 M(OMEGA) Hamon network developed at INRIM to improve the traceability level of the maintained 1 G(OMEGA) standard. Besides the Hamon network, the measurement system, presented in this paper, consists of a precision dc voltage source and an electronic circuit used as voltage guard driver.