US Patent 7215223 Surface acoustic wave device

A surface acoustic wave (SAW) device includes a SAW chip including comb-like electrodes arranged on a piezoelectric substrate, and a package on which the SAW chip is flip-chip mounted, the package including an interconnection that connects the comb-like electrodes. Resonators are connected to signal interconnection pads through the interconnection pattern. IDTs in a three-IDT multimode filter are respectively connected to the signal interconnection pads via another interconnection pattern. The signal interconnection pads are connected to a signal interconnection provided on a chip mounting surface with bumps. Then, a part of the interconnection pattern connecting the resonators is extracted onto the package. It is thus possible to design the interconnections on the package flexibly and thereby easy to adjust the impedance of the interconnections that connect the resonators.