Title :
Precision computer-controlled decade capacitor
Author :
Eckardt, H. ; Behnke, G. ; Bemme, W. ; Semyonov, Yu.P. ; Schvedov, O.A.
Author_Institution :
Phys. Tech. Bundesanstalt, Braunschweig, Germany
Abstract :
A precision computer-controlled decade capacitor switching capacitance values from 100 pF to 1 /spl mu/F in steps of 100 pF with an uncertainty of the order 10/sup -6/ is described. To minimize the temperature influence, special ceramic capacitors with temperature coefficients of 10/sup -6/ K/sup -1/ and low loss factor are used. Switching impedances are avoided by a four-terminal-pair definition of capacitors and quasi-coaxial connection. The capacitor can be used for automatic calibrations of capacitance bridges with a basic accuracy of 10/sup -4/ to 10/sup -5/.
Keywords :
bridge circuits; calibration; capacitance measurement; capacitor switching; ceramic capacitors; computerised control; computerised instrumentation; electric variables control; measurement standards; measurement uncertainty; relays; 100 pF to 1 muF; automatic calibrations; capacitance bridges; capacitance switching; ceramic capacitors; chip capacitor; four-terminal-pair definition; frequency dependence; low loss factor are used; minimized temperature influence; polarized relays; precision computer-controlled decade capacitor; quasi-coaxial connection; step calibration method; summing device; temperature coefficients; uncertainty; Capacitance; Capacitors; Ceramics; Dielectrics; Hysteresis; Impedance; Relays; Temperature dependence; Uncertainty; Voltage;
Conference_Titel :
Precision Electromagnetic Measurements Digest, 1998 Conference on
Conference_Location :
Washington, DC, USA
Print_ISBN :
0-7803-5018-9
DOI :
10.1109/CPEM.1998.700022
