MODELING OF A CAPACITIVE Sigma-Delta MEMS ACCELEROMETER SYSTEM INCLUDING THE NOISE COMPONENTS AND VERIFICATION WITH TEST RESULTS


Boga B., Ocak I. E. , KÜLAH H. , AKIN T.

22nd International Conference on Micro Electro Mechanical Systems (MEMS), Sorrento, İtalya, 25 - 29 Ocak 2009, ss.821-824 identifier identifier

Özet

This paper presents a detailed SIMULINK model for a conventional capacitive Sigma-Delta accelerometer system consisting of a MEMS accelerometer, closed-loop readout electronics, and signal processing units (e. g. decimation filters). By using this model, it is possible to estimate the performance of the full system, including the effect of individual noise components, operation range, scale factor, etc. The model has been verified through test results using a lateral accelerometer, full-custom designed 2nd-order Sigma-Delta readout electronics, and a signal processing unit implemented on PIC. The implemented system operates at 500 kHz sampling rate and has 0.53 V/ g open-loop sensitivity, 58.7 mu g/root Hz resolution, +/-12g operation range, and 0.97e-6 g/(output units) scale factor, where these numbers are in close agreement with the estimated results.