Maximization of the Fundamental Power in Nonlinear Capacitance Diodes

In this paper we consider the problem of determining the maximum fundamental power in a nonlinear capacitance diode, when the charge waveform has a given periodicity and (i) varies between prescribed maximum and minimum values, (ii) has a prescribed maximum and a prescribed maximum slope. Under (i) the maximum obtainable fundamental power is first determined. The charge waveform is then further restricted to contain no higher than second harmonics, so that the diode is being used as a frequency doubler, and the maximum power transfer is determined. The maximum power transfer is also determined under (ii). Particular diodes considered are the abrupt-junction and the graded-junction ones, with operation in the forward conduction region being permitted. I. ENGINEER'S SUMMARY This section of the paper is a summary which stresses some of the contents of the introduction and summary that follow. It is hoped that this will make it easier for the engineer who is involved in parametric amplifier and varactor design to deduce the relevant applications of the results contained in this paper. In the first instance it should be emphasized that an idealized problem, based 011 a mathematical model, is considered. The nonlinear capacitor is assumed to be isolated from any external circuits, and we do not discuss how the power is fed into or taken from the device. Clearly there will be some power lost in the external circuit, and the maximum obtainable fundamental power determined in this paper is only a theoretical maximum, but it would seem to be worthwhile to understand this theoretical maximum.