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arXiv · 1312.1838

Generation of reference dc currents at 1 nA level with the capacitance-charging method

Luca Callegaro·Pier Paolo Capra·Vincenzo D'Elia·Flavio Galliana
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Abstract

The capacitance-charging method is a well-established and handy technique for the generation of dc current in the 100 pA range or lower. The method involves a capacitance standard and a sampling voltmeter, highly stable devices easy to calibrate, and it is robust and insensitive to the voltage burden of the instrument being calibrated. We propose here a range extender amplifier, which can be employed as a plug-in component in existing calibration setups, and allows the generation of currents in the 1 nA range. The extender has been employed in the INRIM setup and validated with two comparisons at 100 pA and 1 nA current level. The calibration accuracy achieved on a top-class instrument is 10 ppm at 1 nA.

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Luca Callegaro, Pier Paolo Capra, Vincenzo D'Elia, Flavio Galliana. 2013-12-06. Generation of reference dc currents at 1 nA level with the capacitance-charging method. https://arxiv.org/abs/1312.1838

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