Elastic Mode Semicircular Beams Resonator Oscillator with Weakened Nonlinearities

This paper reports a single anchored semicircular beams resonator operating at elastic mode with weakened nonlinearities. By introducing curviness to reshape the conventional double ended tuning forks to circular beams, vibration of the resonator transits from stretch to elastic modes. Under elastic mode, the proposed resonator shows only a slight electrical softening nonlinearity in open loop testing. The resonator is then embedded in a phase locked loop to realize a stable oscillation. The oscillator shows an amplitude frequency dependence of only -3ppm/mV
²
at the bifurcation point with maximum output voltage, matching well with open loop testing results, and has over 340 times improvement comparing to that of double ended tuning forks counterpart with the same beam dimensions.