The ARN series is a range of thin film precision chip resistors built on an aluminum nitride (AlN) substrate, a material chosen specifically for its exceptionally high thermal conductivity relative to the alumina substrates used in conventional chip resistors. This thermal advantage allows the ARN series to achieve power ratings significantly above those of standard-footprint chip resistors: 0.5W in the 0603 package, 1.0W in 0805, 2.0W in 1206, and 6.0W in the 2512 footprint, all rated at 70°C ambient. The aluminum nitride substrate conducts heat away from the resistive element efficiently, making the ARN series suitable for compact, high-power-density surface-mount designs where thermal management is a primary concern.
The resistance range spans 50Ω to 30.1kΩ, with tolerance grades of ±0.1%, ±0.25%, ±0.5%, and ±1%, making the series appropriate for both precision measurement circuits and general-purpose high-power applications. Temperature coefficient of resistance (TCR) options of ±25ppm/°C and ±50ppm/°C are available, with the tighter ±25ppm/°C grade ensuring minimal resistance drift across the −55°C to +155°C operating range. Insulation resistance exceeds 9,999MΩ, and the dielectric withstands applied voltages up to 150V or 200V depending on package size.
The thin film construction of the ARN series provides inherently low inductance and stable electrical characteristics, distinguishing it from wirewound alternatives. Qualification testing is conducted in accordance with MIL-STD-202 and JIS-C 5201 standards, covering thermal shock across −55°C to +150°C for 100 cycles, 1,000-hour endurance at rated load, damp heat at 40°C and 90–95% relative humidity, high-temperature exposure at 155°C, and short-time overload testing. The series is RoHS compliant and supplied in tape-and-reel packaging with a two-year shelf life.
Four package variants are offered — ARN03 (0603), ARN05 (0805), ARN06 (1206), and ARN12 (2512) — each sharing the same 0.43mm profile height and a common multilayer construction comprising an aluminum nitride substrate, resistor layer, overcoat, barrier layer, and external electrodes. Part numbering encodes package size, resistance value, tolerance, TCR, power rating, and packaging format, allowing unambiguous specification across the full product matrix.
