Large-signal diode modeling-an alternative parameter-extraction technique

An alternative numerical optimization method of large-signal equivalent-circuit diode modeling using dc and small-signal S-parameter measurements is described. In general, there are two ways to extract the equivalent-circuit parameters to model a nonlinear device such as a diode. They are based on numerical optimization or noniterative analytical procedure. The former is usually better in approximating the device response. Nevertheless, it requires arbitrary selection of a voltage-dependent S-parameter set to obtain the voltage-independent parameters. In this alternative numerical optimization method, an arbitrary selection of a voltage-dependent S-parameter set to obtain the voltage-independent parameters is not required. Validation of this parameter-extraction technique is done via modeling a forward-biased tunnel diode and a reverse-biased varactor diode. The models are further verified by implementing them in designing and developing an oscillator and a voltage-controlled oscillator.