Low frequency noise measurement and analysis of capacitive micro-accelerometers

Noise measurements of micro-accelerometers were performed using a special measurement system. A common spectral behavior of noise is found, with 1/ f noise dominating at low frequencies and white thermal noise being the limiting factor at higher frequencies. Unexpected resonances are also observed in the commercial devices. Most importantly, an acceleration dependent of the noise is found in analog devices and freescale accelerometers, in contrast to prevailing theory.