MEMS gyroscope with three-channel time-division multiplexing detection circuit

Abstract

The application provides a MEMS gyroscope, which comprises a MEMS inertial sensing part, a gyro interface circuit, and a detection circuit and a digital processing circuit. The detection circuit comprises a multiplexer, a detection charge amplifier, a detection mixer and a detection analog-to-digital converter. Each group of inputs of the multiplexer is connected with a detection capacitor group of a corresponding axis, and the output of the multiplexer is connected with the input of the detection charge amplifier. The multiplexer selects the detection capacitor group of each axis in the plurality of axes in turn to be connected with the input of the detection charge amplifier in each strobe cycle in a plurality of continuous strobe cycles based on a strobe signal, and the detection capacitor group of each axis is strobed by the multiplexer for a predetermined time length. In this way, the plurality of axes multiplex the same detection circuit, so as to reduce the circuit area and power consumption.

Description

[Technical Field]

[0001] This invention relates to the field of gyroscope technology, and more particularly to a MEMS (Micro-Electro-Mechanical System) gyroscope. [Background Technology]

[0002] A gyroscope is an angular velocity sensor based on the Coriolis effect. It has advantages such as low power consumption, small size, low cost, and easy integration, and is widely used in aerospace, automotive electronics, robotics and other fields.

[0003] The gyroscope interface circuit is implemented using a highly integrated ASIC (Application Specific Integrated Circuit). ASIC circuits have advantages such as high precision, small size, low cost, and strong environmental adaptability, making them easy to meet the practical needs of mass production and adjustment of MEMS gyroscopes. However, the integration of MEMS gyroscope interface circuits has become a bottleneck restricting the high performance, miniaturization, and low cost of the device.

[0004] The gyroscope interface circuit is divided into two parts: a drive circuit and a detection circuit. The drive circuit is a crucial measurement and control circuit in a MEMS gyroscope. It generates drive signals to control the gyroscope mass to oscillate and stabilize, while simultaneously providing a demodulation reference signal for the detection circuit. The stability of the self-excited drive circuit for silicon gyroscopes is currently one of the challenges. The amplitude and frequency stability caused by the phase noise of the gyroscope drive signal directly affect the angular velocity stability. Traditional analog drive circuits suffer from poor stability and environmental adaptability due to the low reliability and accuracy of analog devices, and their performance parameters are easily affected by factors such as temperature and aging. Furthermore, analog circuits are not suitable for implementing advanced control algorithms. The detection circuit is used to read the sensor's output signal. High-precision gyroscopes place high demands on the detection circuit's capabilities in weak signal detection, noise suppression, error elimination, environmental adaptability, and temperature compensation.

[0005] Furthermore, silicon micro gyroscopes are manufactured using silicon micromachining technology. Due to non-ideal factors such as machining errors, other coupling mechanisms exist between the motion in the driving and sensing directions. The most significant is elastic coupling, which causes a 90-degree phase difference between the detected vibration and the vibration caused by the Coriolis effect; this is called orthogonal error. Orthogonal error directly affects key performance characteristics of the gyroscope, such as zero-bias stability and zero-bias temperature stability.

[0006] In addition, multi-axis gyroscopes have become mainstream. To detect the output signal of the detection capacitor bank for each axis, a detection circuit is required, which increases the circuit area and power consumption.

[0007] Therefore, there is an urgent need to propose a new technical solution to address the above problems. [Summary of the Invention]

[0008] One of the objectives of this invention is to provide a MEMS gyroscope in which multiple channels reuse the same detection circuit to reduce circuit area and power consumption.

[0009] According to one aspect of the present invention, a MEMS gyroscope is provided, comprising: a MEMS inertial sensing section including: multiple sets of detection capacitors for various axes; and a gyroscope interface circuit including: a detection circuit and a digital processing circuit; the detection circuit includes a multiplexer, a detection charge amplifier, a detection mixer, and a detection analog-to-digital converter, the multiplexer including multiple sets of input terminals, output terminals, and gating control terminals, each set of input terminals of the multiplexer being connected to a corresponding set of detection capacitors for one axis, and the output terminal of the multiplexer being connected to the input terminal of the detection charge amplifier. The output of the charge amplifier is connected to the input of the detection mixer, the output of the detection mixer is connected to the input of the detection analog-to-digital converter, the output of the detection analog-to-digital converter is connected to the digital processing circuit, and one output of the digital processing circuit is connected to the gating control terminal. The multiplexer, based on the gating signal of the gating control terminal, sequentially selects the detection capacitor group of each of the three axes to be connected to the input of the detection charge amplifier in each of the multiple gating cycles in a series of consecutive gating cycles. The detection capacitor group of each axis is gating by the multiplexer for a predetermined duration.

[0010] Compared with the prior art, the present invention enables multiple axes to reuse the same detection circuit through a multiplexer, thereby reducing circuit area and power consumption. [Attached Image Description]

[0011] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0012] Figure 1 This is a schematic diagram of the MEMS gyroscope in the first embodiment of the present invention;

[0013] Figure 2 This is a schematic diagram of the MEMS gyroscope in the second embodiment of the present invention;

[0014] Figure 3 This is a schematic diagram showing the relationship between the gating signal and the resonant period in this invention.

Detailed Implementation Methods

[0015] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0016] The term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the invention. The phrase "in one embodiment" appearing in different places throughout this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that excludes other embodiments. Unless otherwise specified, the terms "connected," "linked," and "connected" used herein to indicate electrical connection refer to direct or indirect electrical connection.

[0017] In this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," "coupled," etc., should be interpreted broadly; for example, they can refer to direct connection or indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0018] Figure 1 This is a schematic diagram of the MEMS gyroscope 100 in the first embodiment of the present invention. In the first embodiment, the present invention utilizes the characteristic that the output current of the drive charge amplifier (DCSA) in the drive circuit is in phase and frequency with the useful signal to compensate the input current of the detection charge amplifier (SCSA) in the detection circuit, thereby eliminating the quadrature signal in the detection charge amplifier (SCSA) in the detection circuit that is 90 degrees out of phase with the useful signal, thus improving the zero-bias stability and noise level of the gyroscope.

[0019] like Figure 1 As shown, the MEMS gyroscope 100 includes a MEMS inertial sensing section 110 and a gyroscope interface circuit. The gyroscope interface circuit is a CMOS (Complementary Metal Oxide Semiconductor) circuit. The MEMS inertial sensing section 110 is the sensor device of the MEMS gyroscope 100, and its working principle is to convert the acceleration of the reference frame into a change in the capacitance of the sensor capacitor.

[0020] like Figure 1 As shown, the MEMS inertial sensing section 110 includes: driving capacitor groups D_p and D_n, driving detection capacitor groups D_sense_p and D_sense_n, and detection capacitor groups for one or more axes.

[0021] The gyroscope interface circuit includes: a drive circuit, a detection circuit for one or more axes, a correction capacitor bank QDAC for one or more axes, and a digital processing circuit 121.

[0022] The driving circuit includes a driving charge amplifier DSCA. The first input terminal of the DSCA is connected to one end of the first driving detection capacitor D_sense_p in the driving detection capacitor groups D_sense_p and D_sense_n. The second input terminal of the DSCA is connected to one end of the second driving detection capacitor D_sense_n in the driving detection capacitor groups D_sense_p and D_sense_n. The detection circuit includes one or more axis detection charge amplifiers SCSA. The first input terminal of each axis's SCSA is connected to one end of the first detection capacitor in the corresponding axis's detection capacitor group. The second input terminal of each axis's SCSA is connected to one end of the second detection capacitor in the corresponding axis's detection capacitor group. One end of the first correction capacitor in each axis's correction capacitor group QDAC is connected to the first output terminal of the driving charge amplifier DCSA, and the other end is connected to the first input terminal of the corresponding axis's detection charge amplifier SCSA. One end of the second correction capacitor in each axis's correction capacitor group QDAC is connected to the second output terminal of the driving charge amplifier DCSA, and the other end is connected to the second input terminal of the corresponding axis's detection charge amplifier SCSA.

[0023] Specifically, the MEMS inertial sensing section 110 has three sets of detection capacitors for each axis: sense_x_p and sense_x_n for the x-axis, sense_y_p and sense_y_n for the y-axis, and sense_z_p and sense_x_n for the z-axis. The gyroscope interface circuit includes three detection circuits for each axis and three calibration capacitors for each axis. The detection circuits for each axis are: x-axis, y-axis, and z-axis. The calibration capacitors for each axis are: QDAC_x for the x-axis, QDAC_y for the y-axis, and QDAC_z for the z-axis. One end of the first correction capacitor in the x-axis correction capacitor group QDAC_x is connected to the first output terminal of the driving charge amplifier DCSA, and the other end is connected to the first input terminal of the x-axis detection charge amplifier SCSA_x. One end of the second correction capacitor in the x-axis correction capacitor group QDAC_x is connected to the second output terminal of the driving charge amplifier DCSA, and the other end is connected to the second input terminal of the x-axis detection charge amplifier SCSA_x. Similarly, one end of the first correction capacitor in the y-axis correction capacitor group QDAC_y is connected to the first output terminal of the driving charge amplifier DCSA, and the other end is connected to the first input terminal of the y-axis detection charge amplifier SCSA_y. The other end of the second correction capacitor in the y-axis correction capacitor group QDAC_y is connected to the second output terminal of the driving charge amplifier DCSA, and the other end is connected to the second input terminal of the y-axis detection charge amplifier SCSA_y. One end of the first correction capacitor in the z-axis correction capacitor group QDAC_z is connected to the first output terminal of the driving charge amplifier DCSA, and the other end is connected to the first input terminal of the z-axis detection charge amplifier SCSA_z. One end of the second correction capacitor in the z-axis correction capacitor group QDAC_z is connected to the second output terminal of the driving charge amplifier DCSA, and the other end is connected to the second input terminal of the z-axis detection charge amplifier SCSA_z.

[0024] In one embodiment, the MEMS inertial sensing section 110 may also be provided with a detection capacitor bank for one or two axes. Similarly, the gyroscope interface circuit may also be provided with a detection circuit for one or two axes and a correction capacitor bank for one or two axes.

[0025] like Figure 1As shown, the detection circuit for each axis also includes detection mixers mixer_x, mixer_y, and mixer_z, and detection analog-to-digital converters SADC_x, SADC_y, and SADC_z. The digital processing circuit 121 includes a low-pass filter (LPF) 1211 or a band-pass filter. The two inputs of each axis's detection mixers mixer_x, mixer_y, and mixer_z are connected to the two outputs of the corresponding axis's detection charge amplifiers SCSA_x, SCSA_y, and SCSA_z. The two outputs of each axis's detection mixers mixer_x, mixer_y, and mixer_z are connected to the two inputs of the corresponding axis's detection analog-to-digital converters SADC_x, SADC_y, and SADC_z. The outputs of each axis's detection analog-to-digital converters SADC_x, SADC_y, and SADC_z are connected to the low-pass filter 1211 or band-pass filter of the digital processing circuit 121. The digital processing circuit 121 provides a detection mixing clock signal sen_mix_clk to the detection mixers mixer_x, mixer_y, and mixer_z. The detection mixing clock signal sen_mix_clk is in phase and frequency with the driving clock signal clk_gyro provided to the driving mixer d_mixer. The low-pass filter 1211 or the band-pass filter performs low-pass filtering or band-pass filtering on the digital detection signals BS_SADC_x, BS_SADC_y and BS_SADC_z output by the detection analog-to-digital converters SADC_x, SADC_y and SADC_z for each axis.

[0026] like Figure 1 As shown, the MEMS gyroscope further includes a power supply circuit 130. The output terminal of the power supply circuit 130 is connected to the other end of each capacitor in the driving capacitor group, the driving detection capacitor group, and the detection capacitor group. The power supply circuit 130 provides voltage to the other end of each capacitor in the driving capacitor group, the driving detection capacitor group, and the detection capacitor group.

[0027] like Figure 1 As shown, the driving circuit also includes a comparator Comp, a phase-locked loop PLL, a driving analog-to-digital converter DADC, an automatic gain control digital-to-analog converter AGC_DAC, and a driving mixer d_mixer.

[0028] The digital processing circuit 121 includes an automatic gain control (AGC) module 1212.

[0029] The first input terminal of the comparator Comp is connected to the first output terminal of the driving charge amplifier DSCA, and the second input terminal of the comparator Comp is connected to the second output terminal of the driving charge amplifier DSCA. The reference input terminal ref_pll of the phase-locked loop (PLL) is connected to the output terminal of the comparator Comp. The comparator Comp provides a reference clock to the PLL, and the output terminal of the PLL is connected to the digital processing circuit 121. The PLL generates a phase-locked loop clock pll_clk based on the reference clock.

[0030] The digital processing circuit 121 generates a feedback clock pll_fb_clk that is in phase and frequency with the reference clock based on the phase-locked loop clock pll_clk, and provides the feedback clock pll_fb_clk to the feedback input terminal fb_pll of the phase-locked loop PLL. The digital processing circuit 121 shifts the feedback clock pll_fb_clk by -90 degrees and uses it as the drive clock signal clk_gyro to provide to the drive mixer d_mixer through the drive clock port.

[0031] The two input terminals of the driving analog-to-digital converter (DADCC) are respectively connected to the first and second output terminals of the driving charge amplifier (DSCA) to convert the voltage signal output by the driving charge amplifier (DSCA) into a digital voltage signal. The automatic gain control module (AGC) performs low-pass filtering on the digital voltage signal through the driving low-pass filter (DLPF), and then provides a digital gain control signal (DAC_da) to control the driving amplitude through the PID controller. The digital gain control signal (DAC_da) is converted into an analog gain control signal by the automatic gain control digital-to-analog converter (AGC_DAC) and provided to the driving mixer (d_mixer).

[0032] The driving mixer d_mixer generates a driving signal based on the driving clock signal and the analog gain control signal to drive the mass blocks corresponding to the driving capacitor groups D_p and D_n to perform simple harmonic motion. Because the mass blocks perform simple harmonic motion, the capacitance of the driving detection capacitor groups D_sense_p and D_sense_n changes.

[0033] The charge transfer caused by changes in the driving detection capacitor banks D_sense_p and D_sense_n is sensed and amplified by the driving charge amplifier DCSA, converting it into a voltage signal. Comparator Comp converts the output of the driving charge amplifier DCSA into a square wave signal, which flips at the zero-crossing point of the DCSA output. The phase-locked loop (PLL) uses the output of comparator Comp as its reference clock and outputs a high-frequency clock, a multiple of the reference clock, as the PLL clock pll_clk. The digital processing circuit 121 generates a feedback clock pll_fb_clk based on the PLL clock pll_clk, which is in phase and frequency with the reference clock. This PLL loop enables self-excited startup of the MEMS gyroscope and locks the vibration frequency of the MEMS drive near the drive's resonant frequency, thus ensuring stable operation of the gyroscope.

[0034] The first connection terminal of the driving mixer d_mixer is connected to one end of the first driving capacitor D_p in the driving capacitor group, and the second connection terminal of the driving mixer d_mixer is connected to one end of the second driving capacitor D_n in the driving capacitor group.

[0035] When the driven mass performs simple harmonic motion in a certain direction, if its reference frame has an acceleration not parallel to the direction of the simple harmonic motion, the mass will also experience a Coriolis force perpendicular to the acceleration and the plane of the driving simple harmonic motion, with the phase of this Coriolis force differing from the driving displacement by 90 degrees. This Coriolis force causes the mass to simultaneously perform simple harmonic motion in this perpendicular direction (moving in response to acceleration). This induced motion causes a change in the capacitance of the sensing capacitor bank Sense_p / Sense_n on that axis. The charge transfer caused by this capacitance change is sensed and amplified by the Sense Charge Amplifier (SCSA) and converted into a voltage signal. This voltage signal is then demodulated by the Sense Mixer Clock Signal sen_mix_clk, which is -90 degrees out of phase with fb_pll, leaving a low-frequency acceleration voltage signal. This low-frequency voltage signal is detected by the SADC of that axis and converted into a digital signal. After being filtered by the LPF in the digital processing circuit 121, it becomes the final output of the gyroscope inertial sensing.

[0036] Furthermore, due to non-ideal factors such as manufacturing errors, other coupling mechanisms exist between the motion in the driving and detection directions, causing detection vibrations that are 90 degrees out of phase with those caused by the Coriolis effect. Because the design parameters of the MEMS drive and sensor differ, the quadrature error is often much larger than the actual acceleration signal to be detected, leading to SCSA_x / y / z saturation. SCSA saturation prevents the actual acceleration from being measured. To eliminate the signal coupled from the driving direction to the detection direction, this invention uses a quadrature error correction capacitor bank QDAC_x / y / z (a quadrature error correction capacitor bank along the x / y / z axes) to introduce a current signal in phase with the driving signal into SCSA_x / y / z to eliminate the quadrature error coupled from the MEMS drive.

[0037] In this invention, the digital drive closed-loop circuit enables the gyroscope to start oscillating quickly and effectively improves control accuracy, stability, and environmental adaptability. The detection circuit offers high performance in weak signal amplification and detection, noise suppression, environmental adaptability, and temperature compensation. The quadrature error compensation circuit effectively eliminates quadrature errors in the useful signal, greatly avoiding SCSA saturation. Furthermore, quadrature error compensation reduces the noise level caused by the coupling noise between large-amplitude quadrature errors and clock jitter. The combination of detection circuit and quadrature error compensation ensures the accuracy of gyroscope output signal measurement.

[0038] As mentioned in the background section, the aforementioned gyroscope still uses a detection circuit for each axis's sensing capacitor bank, which increases circuit area and power consumption. Therefore, further improvements are needed.

[0039] Figure 2 This is a schematic diagram of the MEMS gyroscope in the second embodiment of the present invention. Figure 2 MEMS gyroscope and Figure 1 The structures of MEMS gyroscopes are mostly the same, the differences are: Figure 1 Each axis's detection capacitor group is equipped with a separate detection circuit. Figure 2 The three-axis detection capacitor banks are equipped with a unified detection circuit, meaning the three-axis detection capacitor banks share a single detection circuit. (Regarding...) Figure 2 MEMS gyroscope and Figure 1 For the parts of the MEMS gyroscope that have the same structure, please refer to [the relevant documentation / reference]. Figure 1 The description of MEMS gyroscopes in the text will not be repeated here.

[0040] like Figure 2As shown, the detection circuit 125 includes a multiplexer (MUX), a detection charge amplifier (SCSA), a detection mixer (s_mixer), and a detection analog-to-digital converter (SADC). The multiplexer (MUX) has multiple input terminals, output terminals, and gating control terminals. Each input terminal of the multiplexer (MUX) is connected to a detection capacitor bank corresponding to one axis. The output terminal of the multiplexer (MUX) is connected to the input terminal of the detection charge amplifier (SCSA). The output terminal of the detection charge amplifier (SCSA) is connected to the input terminal of the detection mixer (s_mixer). The output terminal of the detection mixer (s_mixer) is connected to the input terminal of the detection analog-to-digital converter (SADC), and the output terminal of the detection analog-to-digital converter (SADC) is connected to the digital processing circuit 121. One output terminal of the digital processing circuit 121 is connected to the gating control terminal of the multiplexer MUX. Based on the gating signal s_chn_slc of the gating control terminal, the multiplexer MUX sequentially selects the detection capacitor group of each of the multiple axes in each gating cycle of a series of gating cycles and connects it to the input terminal of the detection charge amplifier SCSA. The detection capacitor group of each axis is gating by the multiplexer MUX for a predetermined duration.

[0041] In one embodiment, the multiple axis detection capacitor groups are respectively x-axis detection capacitor groups, y-axis detection capacitor groups, and z-axis detection capacitor groups, each detection capacitor group including a first detection capacitor and a second detection capacitor. One end of the first correction capacitor in the x-axis correction capacitor group is connected to the first output terminal of the driving charge amplifier, and the other end is connected to one end of the first detection capacitor in the x-axis detection capacitor group. One end of the second correction capacitor in the x-axis correction capacitor group is connected to the second output terminal of the driving charge amplifier, and the other end is connected to one end of the second detection capacitor in the x-axis detection capacitor group. One end of the first detection capacitor and one end of the second detection capacitor in the x-axis detection capacitor group are respectively connected to the first set of input terminals of the multiplexer MUX. One end of the first correction capacitor in the y-axis correction capacitor group is connected to the first output terminal of the driving charge amplifier, and the other end is connected to one end of the first detection capacitor in the y-axis detection capacitor group. One end of the second correction capacitor in the y-axis correction capacitor group is connected to the second output terminal of the driving charge amplifier, and the other end is connected to one end of the second detection capacitor in the y-axis detection capacitor group. One end of the first detection capacitor and one end of the second detection capacitor in the y-axis detection capacitor group are respectively connected to the second set of input terminals of the multiplexer MUX. One end of the first correction capacitor in the z-axis correction capacitor group is connected to the first output terminal of the driving charge amplifier, and the other end is connected to one end of the first detection capacitor in the z-axis detection capacitor group. One end of the second correction capacitor in the z-axis correction capacitor group is connected to the second output terminal of the driving charge amplifier, and the other end is connected to one end of the second detection capacitor in the z-axis detection capacitor group. One end of the first detection capacitor and one end of the second detection capacitor in the z-axis detection capacitor group are respectively connected to the third set of input terminals of the multiplexer MUX.

[0042] The output of the detection analog-to-digital converter (SADC) is connected to the low-pass filter or band-pass filter of the digital processing circuit 121. The digital processing circuit provides the detection mixer (s_mixer) with a detection mixing clock signal (sen_mix_clk), which is in phase and frequency with the driving clock signal provided to the driving mixer (d_mixer).

[0043] The multiplexer MUX, within a gating loop, first selects the detection capacitor group of one of the three axes and connects it to the two input terminals of the detection charge amplifier; then it selects the detection capacitor group of another of the three axes and connects it to the two input terminals of the detection charge amplifier; finally, it selects the detection capacitor group of the last of the three axes and connects it to the two input terminals of the detection charge amplifier. For example... Figure 3As shown, within a gating cycle, the x-axis is gating first, then the y-axis, and finally the z-axis, and then the gating cycle is repeated. Each axis is gating for a predetermined duration Ts_cnn_slc, which is N times the resonant period Tmems of the simple harmonic motion of the mass block corresponding to the driving capacitor bank, where N is greater than or equal to 2.

[0044] In view of the fact that gyroscopes do not have high requirements for data output rate, this invention adopts a time-division multiplexing detection circuit scheme. This scheme reduces three detection circuits into one, which greatly saves circuit area, reduces power consumption, and has little impact on system performance.

[0045] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0046] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications and variations to the above embodiments within the scope of the present invention.

Claims

1. A MEMS gyroscope, characterized in that, It includes: The MEMS inertial sensing section includes: a detection capacitor bank with multiple axes; The gyroscope interface circuit includes: a detection circuit and a digital processing circuit; The detection circuit includes a multiplexer, a detection charge amplifier, a detection mixer, and a detection analog-to-digital converter. The multiplexer has multiple input terminals, output terminals, and gating control terminals. Each input terminal of the multiplexer is connected to a detection capacitor bank corresponding to one axis. The output terminal of the multiplexer is connected to the input terminal of the detection charge amplifier. The output terminal of the detection charge amplifier is connected to the input terminal of the detection mixer. The output terminal of the detection mixer is connected to the input terminal of the detection analog-to-digital converter. The output terminal of the detection analog-to-digital converter is connected to the digital processing circuit. One output of the digital processing circuit is connected to the gating control terminal. Based on the gating signal from the gating control terminal, the multiplexer sequentially selects the detection capacitor group of each of multiple axes to be connected to the input of the detection charge amplifier in each of a series of gating cycles. The detection capacitor group of each axis is selected by the multiplexer for a predetermined duration. The MEMS inertial sensing section also includes a driving capacitor bank and a driving detection capacitor bank. The gyroscope interface circuit also includes a drive circuit and multiple axis correction capacitor banks. The driving circuit includes a driving charge amplifier, the first input terminal of which is connected to one end of a first driving detection capacitor in the driving detection capacitor group, and the second input terminal of which is connected to one end of a second driving detection capacitor in the driving detection capacitor group. One end of the first correction capacitor in the correction capacitor group of each axis is connected to the first output terminal of the driving charge amplifier, and the other end is connected to one end of the first detection capacitor in the corresponding axis's detection capacitor group. One end of the second correction capacitor in the correction capacitor group of each axis is connected to the second output terminal of the driving charge amplifier, and the other end is connected to one end of the second detection capacitor in the corresponding axis's detection capacitor group. The mass block corresponding to the driving capacitor bank is driven to perform simple harmonic motion, and the predetermined duration is N times the resonant period of the simple harmonic motion, where N is greater than or equal to 2.

2. The MEMS gyroscope according to claim 1, characterized in that, The MEMS inertial sensing section has three sets of detection capacitors for the x-axis, y-axis, and z-axis, respectively. Each set of detection capacitors includes a first detection capacitor and a second detection capacitor. The gyroscope interface circuit includes three axis correction capacitor banks: one for the x-axis, one for the y-axis, and one for the z-axis. One end of the first correction capacitor in the x-axis correction capacitor group is connected to the first output terminal of the driving charge amplifier, and the other end is connected to one end of the first detection capacitor in the x-axis detection capacitor group. One end of the second correction capacitor in the x-axis correction capacitor group is connected to the second output terminal of the driving charge amplifier, and the other end is connected to one end of the second detection capacitor in the x-axis detection capacitor group. One end of the first detection capacitor and one end of the second detection capacitor in the x-axis detection capacitor group are respectively connected to the first set of input terminals of the multiplexer. One end of the first correction capacitor in the y-axis correction capacitor group is connected to the first output terminal of the driving charge amplifier, and the other end is connected to one end of the first detection capacitor in the y-axis detection capacitor group. One end of the second correction capacitor in the y-axis correction capacitor group is connected to the second output terminal of the driving charge amplifier, and the other end is connected to one end of the second detection capacitor in the y-axis detection capacitor group. One end of the first detection capacitor and one end of the second detection capacitor in the y-axis detection capacitor group are respectively connected to the second set of input terminals of the multiplexer. One end of the first correction capacitor in the z-axis correction capacitor group is connected to the first output terminal of the driving charge amplifier, and the other end is connected to one end of the first detection capacitor in the z-axis detection capacitor group. One end of the second correction capacitor in the z-axis correction capacitor group is connected to the second output terminal of the driving charge amplifier, and the other end is connected to one end of the second detection capacitor in the z-axis detection capacitor group. One end of the first detection capacitor and one end of the second detection capacitor in the z-axis detection capacitor group are respectively connected to the third input terminal of the multiplexer.

3. The MEMS gyroscope according to claim 2, characterized in that, The digital processing circuit includes a low-pass filter or a band-pass filter. The output of the detection analog-to-digital converter is connected to a low-pass filter or a band-pass filter of the digital processing circuit. The digital processing circuit provides a detection mixing clock signal to the detection mixer. The detection mixing clock signal is in phase and frequency with the driving clock signal provided to the driving mixer. The low-pass filter or the band-pass filter performs low-pass filtering or band-pass filtering on the digital detection signal of each axis output by the detection analog-to-digital converter. The multiplexer first selects the detection capacitor group of one of the three axes and connects it to the two input terminals of the detection charge amplifier within a gating loop, then selects the detection capacitor group of another of the three axes and connects it to the two input terminals of the detection charge amplifier, and finally selects the detection capacitor group of the last of the three axes and connects it to the two input terminals of the detection charge amplifier.

4. The MEMS gyroscope according to claim 1, characterized in that, It also includes: The power supply circuit has its output terminal connected to the other end of each capacitor in the driving capacitor group, the driving detection capacitor group, and the detection capacitor group.

5. The MEMS gyroscope according to claim 1, characterized in that, The driving circuit also includes a comparator, a phase-locked loop, a driving analog-to-digital converter, an automatic gain control digital-to-analog converter, and a driving mixer. The digital processing circuit includes an automatic gain control module. The first input terminal of the comparator is connected to the first output terminal of the driving charge amplifier, the second input terminal of the comparator is connected to the second output terminal of the driving charge amplifier, the reference input terminal of the phase-locked loop (PLL) is connected to the output terminal of the comparator, the comparator provides a reference clock to the PLL, and the output terminal of the PLL is connected to the digital processing circuit. The digital processing circuit generates a feedback clock that is in phase and frequency with the reference clock based on the phase-locked loop clock, and provides the feedback clock to the feedback input terminal of the phase-locked loop. The digital processing circuit then shifts the feedback clock by -90 degrees and provides it as a drive clock signal to the drive mixer through the drive clock port. The two input terminals of the driving analog-to-digital converter are respectively connected to the first and second output terminals of the driving charge amplifier to convert the voltage signal output by the driving charge amplifier into a digital voltage signal. The automatic gain control module performs low-pass filtering on the digital voltage signal, and then provides a digital gain control signal to control the driving amplitude through a PID controller. This digital gain control signal is converted into an analog gain control signal by the automatic gain control digital-to-analog converter and provided to the driving mixer. The drive mixer generates a drive signal based on the drive clock signal and the analog gain control signal to drive the mass block corresponding to the drive capacitor bank to perform simple harmonic motion. The first connection terminal of the driving mixer is connected to one end of the first driving capacitor in the driving capacitor group, and the second connection terminal of the driving mixer is connected to one end of the second driving capacitor in the driving capacitor group.

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