Equivalent circuit parameter extraction of SAW resonators

It is demonstrated that a useful and accurate model for high-frequency SAW (surface acoustic wave) resonators can be extracted by successive applications of the EIA-512 method. This extraction technique is an adaptation of the Electronic Industries Association (EIA) standard for measurement of the equivalent electrical parameters of quartz crystal units. This method is based on separating the complicated circuits into subcircuits of a form that the EIA-512 procedure can reduce. Bond wire inductance and resistance and package capacitance have been included in this fashion. Once these elements have been extracted from the high-frequency, package parasitic resonance data, their effects are subtracted from the main resonance data by Z- and Y-parameter manipulations. Longitudinal modes can also be extracted in this manner. Two resonators that support the validity of the theory and assumptions are presented