High-sensitivity capacitive silicon micro-accelerometer

In recent year, capacitive silicon micro-accelerometer still is the research hotspot. How to enhance the detection accuracy and further expand its application fields is the emphases and difficulty, which´s key point is to reduce noise. The noise mainly includes mechanical thermal noise and detection circuit noise. The weak signal detection ways are adopted to reduce the noise, to guide the design of sensitive element and the external circuit, to improve the system linearity and resolution. And through the static and dynamic noise test, the noise power spectral density can be tested; the accelerometer sensitivity can also be detected. After testing, we can see that the sensor´s linearity is 1123.2 mv/g^-1, the static noise spectral density is 44.5 ug/radicHz, the dynamic noise power spectral is 0.05 mV/radicHz, which are superior to similar studies.