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dissipation factor (capacitance) (DF)

The dissipation factor(DF) is a characteristic value of passive electronic components and of radio wave absorbing materials. It is expressed as the phase shift between the lossy real part and the loss-free imaginary part and is given as the loss angle tangent. The loss factor is the reciprocal of the quality factor.

  1. As for the dissipation factor of passive electronic components such as coils, capacitors, crystals, filters, antennas and resonant circuits, it is a frequency-dependent quantity that negatively affects the characteristics of the component. The dissipation factor is specified as an angular quantity and is calculated, for example in the case of capacitors, from the equivalent series resistance( ESR) and the capacitance of the capacitor.
    Formula for calculating the dissipation factor

    Formula for calculating the dissipation factor

    The equivalent series resistance is largely determined by the lead resistances and the insulation resistance of the dielectric. In addition, the inductive resistance of the feed line enters into the consideration as a frequency-dependent reactance. The dissipation factor corresponds to the quotient of resistance to reactance and is given as a percentage.
  2. For antennas, the loss factor refers to the power loss resulting from the measurable change in antenna impedance and is related to the power of a theoretical, loss-free antenna.
  3. Regarding the absorption ofmicrowaves, there are materials that absorb microwave energy strongly or less strongly. This property is expressed in the dielectric loss factor and is material, temperature and frequency dependent. This value, which is given as the tangent delta, is calculated from the quotient of the dielectric loss factor and the dielectric constant. For example, polyethylene( PE) has a tangent delta value of 3.1 at 3 GHz, polyvinyl chloride( PVC) has one of 55, and water at room temperature has a tangent delta of 1,600. The high dissipation factor of water shows that microwaves are strongly absorbed by water, thereby heating the water as implemented in microwave ovens.
Englisch: dissipation factor (capacitance) - DF
Updated at: 04.05.2021
#Words: 306
Links: damping factor (DF), phase shift, loss, quality factor (Q), arsenic (As)
Translations: DE

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