KOA is expanding its thin and thick film ranges to meet the needs of demanding applications in automotive, industrial, medical, and aerospace sectors. The extended offering includes high precision metal film flat chip resistors (RN73H and RN73R), high precision thick film resistors (RS73), an expanding selection of anti-sulfuration resistors, and pulse proof high power thick film chip resistors (SG73P1EW).
1. RN73R and RN73H – Highest precision metal film flat chip resistors with excellent long-term stability
KOA offers 2 families of thin film resistors with a T.C.R. down to 5 ppm/°C and a tolerance as low as 0.05%.
The RN73R -series is ideal for high-precision circuits in industrial and measuring applications. This series provides improved electrolytic corrosion resistance and higher stability compared to KOA’s legacy RN73 series which it replaces. The RN73R also has an ambient temperature rating of +85°C, as well as a moisture tolerance of 0.25% at 85% RH for 1000 hours at +85°C.
The RN73H -series is ideal for high precision circuits for automotive and aerospace applications. These thin film resistors have excellent moisture resistance due to an additional inner protective layer. The RN73H has a moisture resistance of 0.1% at 85 % RH for 1000 hours at +85°C.
2. RS73 - High precision thick film resistors 25ppm, 0.1% with excellent long-term stability
The RS73 -series combines the accuracy of thin film with the ruggedness of thick film. With a T.C.R. down to ±25ppm and a tolerance as low as ±0.1%, the new RS73-series from KOA is ideal for precision designs such as high-accuracy sensing or voltage detection circuits in automotive, industrial, and measuring applications.
These new thick film resistors can also be used to replace thin film parts in applications where ESD sensibility is an issue, or higher (pulse) power is needed. The use of these parts in place of thin film devices, can reduce the need for protection components, such as varistors, thus reducing both component count and cost. The RS73 series also features a higher power rating per size and better short time overload performance than thin film.
3. SG73P1EW - Pulse proof high power thick film chip resistors
The SG73P1EW is the latest addition to the popular SG73P pulse stable series. This version of the 0402-size part has an improved power rating of 0.25 W compared to the standard 0402 device. By this high power rating, downsizing of standard flatchip resistors from size 1206 or 0805 to the new SG73P1EW (0402inch) is possible. Additionally, the new SG73P1EW is using a special resistive paste to reach an even better T.C.R. of +-100 ppm/K.
Most thick film surface mount resistors have silver in their terminal construction. Sulfur compounds such as Hydrogen Sulfide and Sulfur dioxide can react with the silver in the terminations and create Silver Sulfide. Over time this process could cause resistor and overall equipment failure.
To eliminate this risk, most KOA thick film resistors are available in anti-sulfuration versions. These resistors are intended to be used within harsh environments with high levels of sulfur contamination and are ideal for automotive, aerospace, and industrial applications where levels of airborne pollutants can be expected.
