Selecting the Right Resistor for High-Temperature Apps (.PDF Download)

Until recently, the limiting factor in high-temperature electronics has been the degradation in semiconductor properties of the active components used. However, with recent advances in high-temperature semiconductors and silicon-carbide-based materials, passive components such as resistors have been the limiting factor. As a result, proper resistor selection has become a critical factor in the design of high-temperature electronics to ensure proper operation and reliability.

Resistors have traditionally been manufactured by a variety of methods and technologies, including metal and metal-oxide film, metal foil, carbon, wirewound, and thick-film methods. Each has specific characteristics that make them more or less suitable for high-temperature applications. Resistor degradation at high temperature can vary from a small resistance change over time to a catastrophic change in resistance, exhibited by either becoming open circuit or, in some cases, a short circuit.