The temperature characteristics of ceramic capacitors are those in which the capacitance changes depending on the operating temperature, and the change is expressed as a temperature coefficient or a capacitance change rate. There are two main types of ceramic capacitors, and the temperature characteristics differ depending on the type. 1.
In plastic type capacitors this temperature value is not more than +700C. The capacitance value of a capacitor may change, if air or the surrounding temperature of a capacitor is too cool or too hot. These changes in temperature will cause to affect the actual circuit operation and also damage the other components in that circuit.
If the surrounding temperature of the capacitor is more than the rated operating temperature, the capacitance of the capacitor can change significantly so it can impact the overall operation of the circuit. The normal working temperature for most practical capacitors is ranging between -30 °C and +125 °C.
The EIA standard specifies various capacitance temperature factors ranging from 0ppm/°C to −750ppm/°C. Figure 1 below shows typical temperature characteristics. And the tables below show the excerpts of applicable EIA and JIS standards. *3 It may differ from the latest JIS standard.
Electrolytic capacitors have high capacitance values. The temperature rise affects the electrolyte’s viscosity and conductivity, affecting the capacitance value and its performance. Also, at extremely cold temperatures, the electrolyte can freeze, affecting its capacitance value. (6). Capacitor Characteristics – Temperature Coefficient:
The capacitance of a capacitor can change value with the circuit frequency (Hz) y with the ambient temperature. Smaller ceramic capacitors can have a nominal value as low as one pico-Farad, ( 1pF ) while larger electrolytic’s can have a nominal capacitance value of up to one Farad, ( 1F ).