Raleigh, N.C. Stackpole Electronics, Inc. has introduced a new line of anti-corrosive precision chip resistors that are said to eliminate moisture concerns typically associated with nickel chromium precision resistors.
Designated the RNCS series, it is available in industry standard 0402 to 2512 case sizes. The devices offer a resistance range from 4.7 ohm (Ω) to 1 MΩ, with tolerances down to ±0.01% and temperature coefficient of resistance (TCR) ratings as low as 5 ppm/°C. The operating temperature range is -55°C to 150°C.
The new series is a result of a significant change to Stackpole's thin-film manufacturing process. The company has added a proprietary passivation layer between the nichrome resistive element and the epoxy overcoat to ensure stable performance and long life in harsh and wet environments. In MIL-STD-202 moisture testing, the RNCS series demonstrated excellent stability over time and showed no significant shift in resistance after the 1,000-hour life test at 85°C and 85% humidity, according to the company.
"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 important over standard nichrome chips and as an alternative to long lead time, high-priced tantalum nitride resistors," said Rob Hudspeth, director of sales and marketing for Stackpole, in a statement.
The company said these new resistors are particularly suitable for precision circuitry where moisture sensitivity and protection against harsh environments are of great concern. Applications include instrumentation, medical equipment, computers, power supplies, telecommunications, automotive, aerospace (where COTS parts are acceptable), and portable electronics.
Pricing for the RNCS series is tolerance and TCR dependent; however, typical pricing is $0.20 in quantities of 1,000. Delivery is four to six weeks. The new series is also available via the company's quick delivery service, SEI Fast.
Stackpole Electronics Inc., 1-919-850-9500, www.seielect.com