Statistical analysis of the characteristics of some basic mass-produced passive electrical circuits used in measurements

摘要

Statistical properties of some basic mass-produced passive electrical circuits used in measurements are analyzed in this paper, using methods for expressing measurement uncertainty of indirectly measured quantities. The focus of this paper is on electrical circuits whose defining parameters are obtained as non-linear functions of component parameters. Variants of voltage divider and Wheatstone bridge circuits significant for measurement practice are investigated in detail. Even if distributions with symmetrical probability density functions (PDFs), such as uniform or normal, are adopted for the parameters of the components comprising a circuit, non-linearity of the circuit function gives rise to asymmetry in the PDF of the circuit's parameter. The asymmetry of the PDF causes the mean and the nominal value of the circuit parameter to differ.