This paper presents an advanced self balancing bridge accelerometer with closed loop digital feedback using the sigma delta-chip. Self-balancing bridge reduces the squeeze film damping by introducing the holes in the structure as add on to the proposed structure. The total area of the electrodes is 7. 44*10-6 as compared to the total area of the holes which is 4. 80*10-7 with no compromise in the nominal capacitance with holes being incorporated in structure. The main issues that have been achieved are good linearity with respect to the plate deflection and a high dynamic range. Advance self balancing bridge accelerometer has been found to be the optimum solution used to measure plate deflection, symmetrical electrostatic forces on the capacitor plates, its offset and output noise.

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Mems Micro-machine Bridge Accelerometer