Novel, simple, and Q-independent self oscillation loop designed for vibratory MEMS gyroscopes

This paper presents a novel self oscillation loop with a very simple architecture that is independent of quality factor (Q) variations in packaged vibratory MEMS gyroscopes, providing identical start-up performance at different ambient conditions. The new self-oscillation loop circuitry has been fabricated in a 0.6μm CMOS process, tested with a fabricated MEMS gyroscope, and demonstrated start-up characteristics without any overshoot and with a settling time of only 28msec. An angle random walk value of 0.037°/√hr and a bias instability value of 3°/hr are achieved using this new self-oscillation loop.