Ajit Sharma

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—In this paper, we report on the design, fabrication, and characterization of an in-plane mode-matched tuning-fork gyroscope (M 2-TFG). The M 2-TFG uses two high-quality-factor (Q) resonant flexural modes of a single crystalline silicon mi-crostructure to detect angular rate about the normal axis. Operating the device under mode-matched condition, i.e.,(More)
—In this paper, the design, implementation and characterization of a continuous time transimpedance-based ASIC for the actuation and sensing of a high-MEMS tuning fork gyroscope (TFG) is presented. A T-network transimpedance amplifier (TIA) is used as the front-end for low-noise, sub-atto-Farad capacitive detection. The T-network TIA provides on-chip(More)
This paper presents the design and implementation of an in-plane solid-mass single-crystal silicon tuning fork gyro that has the potential of attaining sub-deg/hr rate resolutions. A design is devised to achieve high Q in the drive and sense resonant modes (Q drive =81,000 and Q sense =64,000) with effective mode decoupling. The gyroscope was fabricated on(More)
A CMOS ASIC has been designed and interfaced with a high Q MEMS gyroscope to yield an angular rate sensor with a 1.2deg/hr noise floor and 2mV/deg/s rate sensitivity. A T-network transimpedance amplifier (TIA) has been implemented with a measured capacitive resolution of 0.04aF/radicHz, an SNDR of 104dB and which consumes ~ 400muW of power. The TIA also(More)
Micromachined gyroscopes constitute one of the fastest growing segments of the microsensor market. The application domain of these devices is quickly expanding from automotive to consumer and personal navigation systems. Examples include anti-skid and safety systems in cars, and image stabilization in digital cameras. Today, MEMS gyros do not meet the(More)
This paper reports on the design and implementation of an in-plane solid-mass single-crystal silicon tuning fork gyro that has potential to achieve inertial-grade performance. A novel design is devised to achieve high Q in the drive and sense resonant modes (Q drive =84,000 and Q sense =64,000) with effective decoupling. The gyroscope was fabricated on 40µm(More)
This paper presents an architecture that utilizes the often ignored residual quadrature error in a gyroscope to achieve and maintain perfect mode-matching, i.e., ~ 0Hz split between the drive and sense mode frequencies, as well as electronically control the sensor bandwidth. A 6mW, 3V CMOS ASIC and control algorithm have been interfaced with a 60µm thick(More)
—We report on the design, fabrication and characterization of a novel multiple-shell silicon vibratory microgyroscope. The resonating star gyroscope (RSG) is formed as a merged su-perposition of two square shells, yielding in-plane flexural modes that are utilized to sense rotation along the normal axis. The first prototypes of the single-shell RSG were(More)
This paper presents an analytical and experimental study of energy loss mechanisms in a bulk-micromachined tuning fork gyroscope. An exact solution to TED in such devices is obtained and its Debye peak is identified. Compared with its counterpart in a beam resonator of same dimensions, the Debye peak is shifted by a proof mass. For the current design and(More)