Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

New Method for Determining Time Constant of Resistors

Published

Author(s)

Yicheng Wang, Dean G. Jarrett, Andrew D. Koffman, Stephan Schlamminger

Abstract

We report a new method for determining the time constant of ac resistors with values around 10 kΩ, using a digital impedance bridge for comparison of two nominally equal resistors. The method involves adding a probing capacitor in parallel to one of the resistors to induce a quadratic frequency dependence in the real component of the admittance ratio between the two resistors. The magnitude of this quadratic effect is proportional to the self capacitance of the unperturbed resistor, enabling us to determine its value and the associated time constant with an estimated standard uncertainty (k = 1) of 0.02 pF and 0.2 ns, respectively.
Citation
Review of Scientific Instruments
Volume
95

Keywords

ac resistor, time constant, phase angle, digital bridge, impedance standard.

Citation

Wang, Y. , Jarrett, D. , Koffman, A. and Schlamminger, S. (2023), New Method for Determining Time Constant of Resistors, Review of Scientific Instruments, [online], https://doi.org/10.1063/5.0143225, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=936211 (Accessed April 28, 2024)
Created March 21, 2023, Updated June 23, 2023