Automatic Frequency Tuning Technology for Dual-Mass MEMS Gyroscope Based on a Quadrature Modulation Signal

In order to eliminate the frequency mismatch of MEMS (Microelectromechanical Systems) gyroscopes, this paper proposes a frequency tuning technology based on a quadrature modulation signal. A sinusoidal signal having a frequency greater the gyroscope operating bandwidth is applied to the quadrature stiffness correction combs, and the modulation signal containing the frequency split information is then excited at the gyroscope output. The effects of quadrature correction combs and frequency tuning combs on the resonant frequency of gyroscope are analyzed. The tuning principle based on low frequency input excitation is analyzed, and the tuning system adopting this principle is designed and simulated. The experiments are arranged to verify the theoretical analysis. The wide temperature range test (-20 ∘ C –60 ∘ C ) demonstrates the reliability of the tuning system with a maximum mismatch frequency of less than 0.3 Hz. The scale factor test and static test were carried out at three temperature conditions (−20 ∘ C, room temperature, 60 ∘ C), and the scale factor, zero-bias instability, and angle random walk are improved. Moreover, the closed-loop detection method is adopted, which improves the scale factor nonlinearity and bandwidth under the premise of maintaining the same static performances compared with the open-loop detection by tuning.

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The Simulation Analysis of Temperature Effects on System Performance of Silicon Micro-Gyroscope

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.529.375 ◽

2014 ◽

Vol 529 ◽

pp. 375-378

Author(s):

Yun Peng Deng ◽

Bo Yang ◽

Xing Jun Wang ◽

Bo Dai

Keyword(s):

System Performance ◽

Closed Loop ◽

Simulation Analysis ◽

Simulation Models ◽

Temperature Characteristic ◽

Open Loop ◽

Scale Factor ◽

Drive System ◽

Zero Bias ◽

Relative Change

The effects of temperature variation on the system performance is discussed in this paper. The temperature characteristic of the natural frequency and quality factor is analyzed theoretically firstly. Then the simulation models of the open-loop drive system, the closed-loop drive system, the closed-loop sense system and the quadrature correction system are constructed to simulate the temperature characteristic of the scale factor and zero bias. The simulation results demonstrate the relative change of the scale factor in the closed-loop drive system, that is 1.35%, almost decreases by 67 times relative to the open-loop drive system and the variation of the zero bias in the closed-loop drive system, that is 0.2789°/s, almost decreases by 364 times relative to the open-loop drive system. At the same time, the relative change of the scale factor in the closed-loop sense system, that is 0.000029%, almost decreases by 46551 times relative to the closed-loop drive system. The variation of the zero bias in the closed-loop sense system, that is 1.2×10-11°/s, almost decreases by 2.3×1010 times relative to the closed-loop drive system, which shows the proposed method is feasible and correct.

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Design of Low Voltage Low Power LPF for WSN Node

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.760-762.54 ◽

2013 ◽

Vol 760-762 ◽

pp. 54-59

Author(s):

Yang Lin ◽

Zhi Qun Li ◽

Chen Jian Wu ◽

Meng Zhang ◽

Zeng Qi Wang

Keyword(s):

Low Power ◽

Low Voltage ◽

Frequency Tuning ◽

Cmos Technology ◽

Pass Band ◽

Automatic Frequency ◽

Temperature Deviation ◽

Op Amp ◽

Active Rc Filter ◽

Operation Amplifier

A fourth-order low-pass continuous-time filter for a WSN transmitter is presented. The active RC filter was chosen for the high linearity, designed by using the leapfrog topology imitates the passive filter. The operation amplifier (op-amp) adopted by the filter is feed-forward operation amplifier, which could get the GBW as large as possible under the low power consumption. The cut-off frequency deviation due to the process corner, aging and temperature deviation is adjusted by an automatic frequency tuning circuit. The filter in a 0.18μm RF CMOS technology consumes 1mW from a 1V power supply. The measured results of the chip show that the bandwidth is about 1.5MHz. The voltage gain of filter is about-4.5dB with the buffer, the ripple in the pass-band is lower than 0.5 dB, and the channel rejection ratio is larger than 30dB at 4MHz.

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A 2-v/sub pp/ 80-200-mhz fourth-order continuous-time linear phase filter with automatic frequency tuning

IEEE Journal of Solid-State Circuits ◽

10.1109/jssc.2003.817595 ◽

2003 ◽

Vol 38 (10) ◽

pp. 1745-1749 ◽

Cited By ~ 42

Author(s):

Mingdeng Chen ◽

J. Silva-Martinez ◽

S. Rokhsaz ◽

M. Robinson

Keyword(s):

Fourth Order ◽

Continuous Time ◽

Frequency Tuning ◽

Automatic Frequency ◽

Linear Phase ◽

Phase Filter ◽

Automatic Frequency Tuning ◽

Time Linear ◽

Order Continuous

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MEMS Gyroscope Automatic Real-Time Mode-Matching Method Based on Phase-Shifted 45° Additional Force Demodulation

Sensors ◽

10.3390/s18093001 ◽

2018 ◽

Vol 18 (9) ◽

pp. 3001 ◽

Cited By ~ 8

Author(s):

Feng Bu ◽

Dacheng Xu ◽

Heming Zhao ◽

Bo Fan ◽

Mengmeng Cheng

Keyword(s):

Real Time ◽

Microelectromechanical Systems ◽

Control Variable ◽

Mode Frequency ◽

Mode Matching ◽

Sense Mode ◽

Zero Bias ◽

Real Time Mode ◽

Additional Force ◽

Force Signal

In order to solve the problem where existing mode-matching methods in microelectromechanical systems (MEMS) vibrating gyroscopes fail to meet real-time and reliability requirements, this paper presents a novel method to accomplish automatic and real-time mode-matching based on phase-shifted 45° additional force demodulation (45° AFD-RM). The phase-shifted 45° additional force signal has the same frequency as the quadrature force signal, but it is phase-shifted by 45° and applied to the sense mode. In addition, two-way phase-shifted 45° demodulations are used at the sense-mode detection output to obtain a phase metric that is independent of the Coriolis force and can reflect the mode-matching state. Then, this phase metric is used as a control variable to adaptively control the tuning voltage, so as to change the sense-mode frequency through the negative stiffness effect and ultimately achieve real-time mode-matching. Simulation and experimental results show that the proposed 45° AFD-RM method can achieve real-time matching. The mode frequency split is controlled within 0.1 Hz, and the gyroscope scale factor, zero-bias instability, and angle random walk are effectively improved.

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