Package and PCB effects on linearity of a micromixer-based W-CDMA upconverter

The linearity issue of a micromixer-based WCDMA upconverter chip when packaged and then surfacemounted onto a printed circuit board (PCB) for testing has been studied. In this research, the equivalent circuits for package and PCB interconnects are established with the help of three-dimensional electromagnetic simulation tool. The resulting effects on the upconverter linearity are then simulated. The dominant effects include the reduction in conversion gain and the shift and filling of intermodulation notch. Comparison between simulation and measurement shows excellent agreement.