Effect of stress on matched-mode gyroscope frequencies

This paper reports on the simulation and measurement of stress effects on matched-mode gyroscope resonance frequencies using two different stress application setups. First generation stress application setup that requires turning bolts to induce stress is used with a package-level vacuum system that doesn´t require any special packaging equipment. The second generation stress application setup that requires applying load from the center is implemented with a custom made vacuum chamber. It has been shown that stress may increase or decrease the resonance frequencies depending on its effects on the gyroscope anchors. The effect of die orientation on the stress vs. frequency shift is also investigated.