Precision chip resistors handle high humidity

By Gina Roos, editor-in-chief

Stackpole Electronics Inc. offers a family of tantalum nitride thin-film chip resistors that can be used in high-humidity environments. The RTAN series  resistors are impervious to corrosion caused by moisture thanks to their self-passivating property, which make them an alternative to nichrome thin-film precision resistors, which can be susceptible to corrosion in high-moisture conditions.

The RTAN series is available with tolerances of 0.1% and tighter and a temperature coefficient of resistance (TCR) of 25 ppm or better. The resistors withstand biased humidity testing at 85°C, 85% relative humidity, 10% rated power with very little resistance shift. In addition, the anti-sulfur materials and design of the RTAN series enable the resistors to pass the ANSI/EIA-977 (Method A) standard sulfur test with minimal resistance shift.

These precision resistors can be used in a variety of applications requiring precision resistance with long-term stability and environmental robustness, including instrumentation, aerospace, test equipment, industrial controls, automotive electronics, portable communications, diagnostic equipment, and portable medical devices.

The AEC-Q200−qualified RTAN family provides resistance values from 10 to 1 MΩ with TCs of 10 ppm to 50 ppm in case sizes from 0402 to 1206. They are available in 0.05% to 1% tolerances. Many popular resistance values are currently in stock in the 0805 and 1206 sizes with a 0.1% tolerance and 25-ppm TCR.

Pricing for the RTAN depends on size, TCR, and tolerance but ranges from $0.75 to $0.76 each in full-reel quantities. Volume pricing is available from Stackpole or one of its authorized distributors.