Frequency divider with varactor diode

摘要

A varactor diode (VD), having an internal non-linear reactive resistance component, permits the formation of partial ratios of an input signal frequency. The dependence of the varactor diode capacitance (C) on the diode voltage (U) is given by a specific formula, related to a capacitance (Co) at zero voltage. The formula also relates to the voltage ( phi ) at the inner diode contacts, and to an exponent of the capacitance-voltage characteristic dependent on the varactor diode properties. The diode voltage dependency exponential has a maximum value which exceeds 0.5. The working point of the varactor diode is related to the maximum value of the exponent ( psi ).