Stackpole Adds Passivated Resistors for Critical Applications
Stackpole Electronics, Inc. has introduced a new line of anti-corrosive precision chip resistors that eliminates moisture concerns associated with typical Nickel Chromium precision resistors.
Designated the RNCS Series, it is available in industry standard 0402 to 2512 sizes and has a resistance range from 25Ω to 600KΩ, with tolerances down to ± 0.01% and TCRs as low as 5ppm/°C. The RNCS Series has an operating temperature range of -55°C to +155°C.
Manufacture of the new RNCS Series was made possible due to a significant change in manufacturing processes. A proprietary passivation layer is introduced between the nichrome resistive element and the epoxy overcoat to ensure stable performance and long life in the harshest and wettest environments. In MIL-STD-202 moisture testing, the RNCS Series demonstrated excellent stability over time and no significant shift in resistance after the 1000-hour life test at 85°C and 85% humidity.
"In the past few years much has been made over the moisture susceptibility of standard nichrome resistors. This specially passivated, moisture-resistant technology was developed as an improvement over standard nichrome chips and as an alternative to long lead time, high priced tantalum nitride resistors," said Kory Schroeder, Product Engineering Manager at Stackpole.
Schroeder added, "We have completed extensive moisture comparison testing. In every case the RNCS series outperformed standard nichrome chip resistors and demonstrated the same anti-corrosive characteristics of costly tantalum nitride resistor products."
The RNCS Series is targeted for precision circuitry where moisture sensitivity and protection against harsh environments are of great concern. Typical applications and markets include instrumentation, medical equipment, computers, power supplies, telecommunication, automotive, aerospace (where COTS parts are accepted) and portable electronics
RNCS Series pricing is tolerance and TCR dependent, but $0.20 is typical in quantities of 1,000 pieces. Leadtime for the RNCS Series is 4 to 6 weeks.
