An Ultra-Low-Power Third-Order Frequency-to-Digital Converter for FM MEMS Gyroscope

Compared with traditional AM gyroscope, FM operation brings about wider dynamic range and more stable scale factor and bias. A third-order noise shaping frequency-to-digital converter is proposed in this paper to improve FM gyroscope's ultimate precision. It achieves 8μHz or 10dph resolution in 10Hz bandwidth with only 200kHz reference clock frequency. The full scale is 2000dps, corresponding to a dynamic range of 117dB with 1.26μW power consumption. This ultra-low-noise and low-power frequency-to-digital converter enables the development of high performance FM gyroscope.

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