The autonomous impact resonator: a new operation principle for a silicon resonant strain gauge

A new oscillation principle for silicon resonators is described. Using only a capacitive microbridge, a resistor and a d.c. source, an autonomous oscillator can be obtained without the need for an external oscillator circuit. An electromechanical model is derived and a general mathematical description is given. The behaviour of the autonomous impact oscillator is simulated and a stability analysis is presented. Experimental results validate the proposed oscillation mechanism.