Frequency Trimming for MEMS Resonator Oscillators

This paper presents various frequency trimming methodologies with the focus on silicon based micromechanical resonators. The techniques include mechanical trimming and pure electronic trimming. The experimental results showed the frequency accuracy have reached 2.6 ppm for mechanical trimming and lppm for electronic trimming. Furthermore, the technique of digital electronic trimming resolved the temperature compensation issues for MEMS resonators at the same time.