Dissipation factor of capacitor
The capacitance dissipation factor refers to the power loss when alternating current is applied to the capacitor. This power will be absorbed by dielectric materials or internal/external resistance. To the outside, leads, pads, and solder all cause resistance to increase.
A high dissipation factor may shorten the life of the capacitor and cause deterioration of the electrical performance of other components that are susceptible to temperature rise. Adding components such as fans and radiators can alleviate this temperature increase, but it will increase weight and cost.
The formula of the dissipation factor is the series resistance divided by the capacitive reactance, namely DF=RS/XC.
Another more common term is Q factor (also called quality factor). The Q factor is the mathematical inverse of the dissipation factor; QF increases as DF decreases. The Q factor can be calculated by dividing the capacitive reactance by ESR, that is, Q=Xc/ESR.
In order to minimize the dissipation factor in the circuit, you may need to choose a capacitor with a higher Q factor and reduce the resistance in the circuit. Methods to reduce resistance include improving the performance of pads and conductors, and cleaning solder joints. This means that materials need to be replaced, which will increase costs, but will also achieve better results.
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