First off the Q of the tuned circuits in switch mode amplifiers is less an
issue than the effective capacitance and at high power ESR is a
efficiency and heating consideration.??
There are two mechanisms for capacitors one is lead or structure resistance
which is independent of dielectric.? It is effectively series R.
The other is the dielectric loss (tan delta) and that is thought of as both series
(related to structure) and parallel R as a function of loss in the material itself.?
For multilayer metalized capacitors the series R function is a structural and?
materials action from the metalization, its skin depth and material. A good
example of high power caps are the metal clasp micas such as those from
Unelco.
For the moment I left out any inductance as most MLC and similar part
that is a smallest part of the parasitics.? However at UHF that is a?
factor.
--
Allison
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