Measurement of the low temperature electrical properties of solid tantalum capacitors

Highly reproducible capacitance–low temperature and dissipation factor–low temperature curves were obtained for commercial solid tantalum electrolytic capacitors in the range 90–310 K. A description of a design of a cryostat used to test radial wire ended tantalum bead capacitors at low temperatures is given. The tantalum capacitors showed excellent capacitance–temperature linearity between 220 and 310 K for test frequencies of 120 Hz and 1 kHz. Some evidence is given for the presence of dielectric relaxation at ∼210 K.