ENCAPSULATED MICROMECHANICAL GYRO AND ACCELEROMETERS FOR DIGITAL CONTROL SYSTEMS

摘要

There is no general consensus of opinion about the future of micromechanical gyroscopes and accelerometers. According to the pessimistic estimation, micromechanical gyroscopes and accelerometers have attained the limit of their accuracy. However optimists believe that micromechanical gyroscopes will soon occupy the niche of fiber-optical gyroscopes and the latter will press laser gyroscopes. The present-day development of micromechanical gyroscopes and accelerometers is aimed at improving the basic and minor parameters: sensitivity, bias, offset, drift, resolution, scale factor and its nonlinearity, etc. High level of performance is provided by application of high technology. The paper is devoted to the development and manufacturing of 'silicon-glass' micromechanical sensors of encapsulated type with digital output processing. The key technological processes allowing production of micromechanical encapsulated sensors with vacuum inside are considered and the features of their design are described. The methods for maintaining high reliability of encapsulated micromechanical gyroscopes with inner getter structure are discussed. ASIC designs for control and processing of micromechanical sensor outputs allow their accuracy, which is part of modern integrated systems, to be considerably improved. Also considered are various assemblies and packaging of the ASIC and micromechanical sensor as a single product.