High-stability resistors for demanding HV uses

Edited by the Electronicstalk editorial team Dec 17, 2002

Caddock has developed a range of ultrastable low-TC resistors for use in the most demanding precision high-voltage applications.

Caddock has developed a range of ultrastable low-TC resistors for use in the most demanding precision high-voltage applications.

The Type USG is available in three models with voltage ratings (and standard resistance values) of 5kV (50 and 75Mohm), 10kV (100 and 150Mohm), and 15kV (150 and 200Mohm).

The Type USG uses Caddock's proven Tetrinox resistance film system with selected core materials and physical geometry to optimise the low TC and ultrastable performance of these resistors in voltage ratings and resistance values to fit a variety of high performance high voltage systems.

The Type USG offers outstanding thermal and long-term stability.

The ultralow temperature coefficient of 10ppm/degC from -40 to +85C (ref to +25C) means minimal startup drift and excellent stability over a wide temperature range.

The load-life stability is outstanding: typical resistance change after 1kh at full rated voltage at 85C is 0.025%, the maximum change is 0.05%.

The voltage coefficient is also very low.

Precision high voltage resistive dividers can be formed using catalogue standard resistors of the Type USG and the Type USF ultrastable precision film resistors or "matched" with selected Type TK low-TC precision film resistors.

Custom low-TC high-voltage strings are available for higher system voltages (30 to 200kV and higher).

Applications for the Type USG include ultrastable high-voltage power supplies for electron microscopes, semiconductor manufacturing equipment, spectrographic equipment and other precision high-voltage power supplies for laboratory, research and industrial applications.