Activation of different MEMS resonant modes with pulsed digital oscillators

The objective of this work is to show that it is possible to excite different vibration modes of MEMS resonators using Pulsed Digital Oscillators. This class of circuits exhibit two different behaviours: the oscillation and the anti-oscillation mode. In the oscillation mode, the oscillator in average provides energy to the resonator, whereas in the anti-oscillation mode, it extracts energy of the resonator until a limit cyucle is reached near the origin. It will be shown that by preparing suitable PDO configurations it is possible to selectively excite different resonant modes of a MEMS resonator. The experimental corroboration has been obtained with a scanning Doppler vibrometer.