What are the important reference parameters for thin-film power resistors?

The application of thin film resistors in improving power requires attention to the following important reference parameters:

Resistance value: refers to the impedance of a resistor under specific conditions, usually expressed in ohms (Ω). The resistance value is determined by multiple factors such as the material, aspect ratio, electrode spacing, and thickness of the resistor. The common resistance values range from a few ohms to several megaohms. For thin-film power resistors, an appropriate resistance value can ensure that the current and voltage in the circuit are within the required operating range, thereby meeting the demand for power enhancement.
Stability: refers to the degree of change in resistance value during use, divided into initial stability and long-term stability. Initial stability refers to the change in resistance value of a resistor within a short period of time after production, while long-term stability refers to the change in resistance value of a resistor during long-term use. Stability is affected by factors such as materials, manufacturing processes, and usage conditions. Thin film power resistors require high stability to ensure that the resistance value does not undergo significant changes under long-term high-power working conditions, thereby ensuring the stability and reliability of the circuit.
Temperature coefficient: refers to the degree to which the resistance value changes with temperature, expressed in ppm/℃ (parts per million/degree Celsius). The temperature coefficient is one of the important parameters of thin film resistors, as the stability of the resistance value changes with temperature. For thin-film power resistors, a lower temperature coefficient means that the resistance value changes less with temperature, which helps maintain circuit stability under high-power operating conditions. The temperature coefficient of common thin film resistors is 50ppm/℃, 100ppm/℃, 250ppm/℃, etc.
Power: refers to the maximum power that a resistor can withstand, expressed in watts (W). The power is determined by factors such as the size, material, and manufacturing process of the resistor. Thin film power resistors need to have high power tolerance to meet the requirements of high-power working conditions. However, the power of thin film resistors is generally small, usually less than 1W, so it is necessary to perform reasonable power derating treatment in practical applications to ensure their long-term stability and reliability.
In summary, important reference parameters for thin-film power resistors include resistance value, stability, temperature coefficient, and power. When selecting and designing thin-film power resistors, it is necessary to comprehensively consider these parameters to meet the specific application requirements.