Dynamic Parameters Measurement System of MEMS Gyroscope

Abstract

The present invention provides a dynamic parameter measurement system for a MEMS gyroscope. The system includes: a signal source, a signal conditioning circuit and a host computer; the signal source is used to generate a driving signal and a detection carrier signal based on the driving modal frequency and the detection modal frequency of the MEMS gyroscope to be measured; the signal conditioning circuit is used to superimpose the driving signal and the preset driving carrier signal, and input the superimposed signal to the driving electrode; the detection carrier signal is input to the detection electrode; the host computer is used to collect the first output signal of the intermediate plate, and perform spectrum analysis on the first output signal to obtain the first sum frequency signal and the first difference frequency signal, as well as the second sum frequency signal and the second difference frequency signal; based on the amplitude of the first sum frequency signal, the amplitude of the second sum frequency signal, the amplitude of the first difference frequency signal and the amplitude of the second difference frequency signal, the orthogonal coupling coefficient of the MEMS gyroscope to be measured is determined. The present invention can realize on-chip measurement of the orthogonal coupling coefficient of the MEMS gyroscope.

Description

Technical Field

[0001] The present invention relates to the technical field of gyroscopes, and in particular to a dynamic parameter measurement system of a MEMS gyroscope. Background Art

[0002] Micro Electro Mechanical Systems (MEMS) gyroscopes can provide speed status information for moving objects and are key components for attitude measurement and control of many intelligent systems. Due to their low price, small size, low power consumption and high reliability, MEMS gyroscopes are widely used in applications such as drones, self-driving cars and self-balancing vehicles. They are the most widely used products in the gyroscope family.

[0003] In the mass production of MEMS gyroscopes, it is necessary to measure the dynamic parameters of the MEMS gyroscope, such as the driving modal frequency, damping ratio, quality factor, and orthogonal coupling coefficient, so as to realize the performance detection of the MEMS gyroscope, eliminate unqualified products, and reduce the subsequent waste of manpower and material resources.

[0004] At present, the Ring-Down method, closed loop disconnection, white noise excitation method and other methods are mainly used to measure dynamic parameters such as driving modal frequency, quality factor, bandwidth and damping ratio. However, there is no effective measurement method to achieve on-chip measurement of the dynamic parameter of orthogonal coupling coefficient.

[0005] In related technologies, the ratio of the amplitude of the detection mode to the driving mode in static state (i.e., zero angular velocity input state) is usually called the orthogonal coupling coefficient. The orthogonal coupling coefficient reflects the strength of the driving amplitude coupling to the detection amplitude. The size of the gyro orthogonal coupling coefficient has a great influence on the gyro zero bias and its temperature coefficient. The size of the orthogonal coupling coefficient also reflects the process control level of non-ideal factors such as process stress and process structure dimensional error.

[0006] Therefore, it is necessary to perform on-wafer testing on the MEMS gyroscope during the MEMS mass production process to determine the orthogonal coupling coefficient of the MEMS gyroscope and to promptly remove the MEMS gyroscope with unqualified orthogonal coupling coefficient. Summary of the invention

[0007] The embodiment of the present invention provides a dynamic parameter measurement system of a MEMS gyroscope to achieve on-chip measurement of the orthogonal coupling coefficient of the MEMS gyroscope.

[0008] In a first aspect, an embodiment of the present invention provides a dynamic parameter measurement system of a MEMS gyroscope, comprising: a signal source, a signal conditioning circuit and a host computer;

[0009] Signal source for:

[0010] generating a driving signal based on a driving modal frequency of the MEMS gyroscope to be tested;

[0011] Generating a detection carrier signal based on the detection modal frequency of the MEMS gyroscope to be tested;

[0012] Signal conditioning circuits for:

[0013] Superimposing the driving signal and a preset driving carrier signal, and inputting the superimposed signal to the driving electrode of the MEMS gyroscope to be tested;

[0014] Inputting the detection carrier signal to the detection electrode of the MEMS gyroscope to be tested;

[0015] The host computer is used for:

[0016] The first output signal of the intermediate plate of the MEMS gyroscope to be tested is collected via the signal conditioning circuit, and the first output signal is subjected to spectrum analysis to obtain a first sum frequency signal and a first difference frequency signal corresponding to the amplitude of the driving mode of the MEMS gyroscope to be tested, and a second sum frequency signal and a second difference frequency signal corresponding to the amplitude of the detection mode of the MEMS gyroscope to be tested;

[0017] The orthogonal coupling coefficient of the MEMS gyroscope to be tested is determined based on the amplitude of the first sum frequency signal, the amplitude of the second sum frequency signal, the amplitude of the first difference frequency signal, and the amplitude of the second difference frequency signal.

[0018] Optionally, the host computer is used to:

[0019] according to Determining the orthogonal coupling coefficient of the MEMS gyroscope to be tested;

[0020] in, represents the orthogonal coupling coefficient, represents the amplitude of the second sum frequency signal, represents the amplitude of the second difference frequency signal, represents the amplitude of the first sum-frequency signal, Indicates the amplitude of the first difference frequency signal.

[0021] Optionally, the signal source is also used for:

[0022] Generate a preset sweep frequency signal, apply the sweep frequency signal to the drive electrode of the MEMS gyroscope to be tested via the signal conditioning circuit, and cancel the sweep frequency signal after maintaining the preset time length;

[0023] The host computer is also used for:

[0024] The second output signal of the intermediate plate of the MEMS gyroscope to be tested is collected via the signal conditioning circuit; the second output signal is used to characterize the natural attenuation oscillation of the amplitude of the driving mode of the MEMS gyroscope to be tested;

[0025] Determining the driving modal frequency of the MEMS gyroscope to be tested based on the second output signal and a natural decay oscillation theoretical expression of the amplitude of the driving modal of the MEMS gyroscope to be tested;

[0026] The natural decay oscillation theoretical expression of the amplitude of the driving mode of the MEMS gyroscope to be tested is: ;

[0027] in, A naturally decaying oscillation signal representing the amplitude of the driving mode of the MEMS gyroscope to be tested, represents the damping ratio of the MEMS gyroscope to be tested, represents the driving modal frequency of the MEMS gyroscope to be tested, Indicates time, Indicates the damped oscillation frequency of the MEMS gyroscope to be tested.

[0028] Optionally, the host computer is also used for:

[0029] Determining the damping ratio of the MEMS gyroscope to be tested based on the second output signal and a natural decay oscillation theoretical expression of the amplitude of the driving mode of the MEMS gyroscope to be tested;

[0030] The quality factor of the MEMS gyroscope to be tested is determined based on the damping ratio of the MEMS gyroscope to be tested.

[0031] Optionally, the host computer is used to:

[0032] according to Determining the quality factor of the MEMS gyroscope to be tested;

[0033] in, represents the quality factor of the MEMS gyroscope to be tested, represents the damping ratio of the MEMS gyroscope to be tested.

[0034] Optionally, the signal source is also used for:

[0035] Generate a preset sweep frequency signal, apply the sweep frequency signal to the detection electrode of the MEMS gyroscope to be tested via the signal conditioning circuit, and cancel the sweep frequency signal after maintaining the preset time length;

[0036] The host computer is also used for:

[0037] The third output signal of the intermediate plate of the MEMS gyroscope to be tested is collected via the signal conditioning circuit; the third output signal is used to characterize the natural attenuation oscillation of the amplitude of the detection mode of the MEMS gyroscope to be tested;

[0038] Determine the detection modal frequency of the MEMS gyroscope to be tested based on the third output signal and a natural decay oscillation theoretical expression of the amplitude of the detection mode of the MEMS gyroscope to be tested;

[0039] The natural decay oscillation theoretical expression of the amplitude of the detection mode of the MEMS gyroscope to be tested is: ;

[0040] in, A naturally decaying oscillation signal representing the amplitude of the detection mode of the MEMS gyroscope to be tested, represents the damping ratio of the MEMS gyroscope to be tested, represents the detection modal frequency of the MEMS gyroscope to be tested, Indicates time, Indicates the damped oscillation frequency of the MEMS gyroscope to be tested.

[0041] Optionally, the system further comprises: a probe station and a probe card; the MEMS gyroscope to be tested is placed on the probe station, and the driving electrode, the detection electrode and the intermediate plate of the MEMS gyroscope to be tested are connected to the probe card;

[0042] The signal conditioning circuit is used to:

[0043] Superimposing the driving signal and a preset driving carrier signal, converting the superimposed signal into a first differential signal, and inputting the first differential signal to the driving electrode of the MEMS gyroscope to be tested via the probe card;

[0044] The detection carrier signal is converted into a second differential signal, and the second differential signal is input to the detection electrode of the MEMS to be tested via the probe card.

[0045] Optionally, the system further includes a capture card;

[0046] The signal conditioning circuit is used to:

[0047] Collecting a current signal output by the middle plate of the MEMS gyroscope to be tested via the probe card, and converting the current signal into a voltage signal to obtain a first output signal;

[0048] The first output signal is input to the host computer via the acquisition card.

[0049] Optionally, the mathematical expression of the driving signal is: ; The mathematical expression of the detected carrier signal is: ;

[0050] in, represents the driving signal, represents the driving modal frequency, represents the detected carrier signal, represents the detected modal frequency.

[0051] Optionally, the mathematical expression of the preset driving carrier signal is: ;

[0052] in, Represents the driving carrier signal, Indicates the frequency of the driving carrier signal. The frequency of the driving carrier signal is any frequency value in the range of 10kHz~30kHz.

[0053] The embodiment of the present invention provides a dynamic parameter measurement system for a MEMS gyroscope, which generates a driving signal and a detection carrier signal based on the driving modal frequency and the detection modal frequency of the MEMS gyroscope to be tested by using a signal source, then superimposes the driving signal on the driving carrier signal by using a signal conditioning circuit, and applies the superimposed signal and the detection carrier signal to the MEMS gyroscope to be tested to drive the MEMS gyroscope to be tested, then by collecting the first output signal of the intermediate plate of the MEMS gyroscope to be tested, the sum frequency signal and the difference frequency signal corresponding to the driving modal amplitude and the detection modal amplitude of the MEMS gyroscope to be tested can be analyzed, and then the orthogonal coupling coefficient can be obtained according to the amplitude of the sum frequency signal and the difference frequency signal. The embodiment of the present invention can not only realize the measurement of the orthogonal coupling coefficient, but also, by superimposing and modulating the driving signal on the driving carrier signal and applying the detection carrier signal at the same time, the amplitude of the driving mode and the amplitude of the detection mode can be modulated at high frequency, thereby effectively avoiding the influence of the driving modal frequency on the electrical coupling caused by the circuit parasitic parameters and the low-frequency noise on the test error, and improving the measurement accuracy of the orthogonal coupling coefficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0055] Figure 1 It is a structural schematic diagram of a dynamic parameter measurement system of a MEMS gyroscope provided by an embodiment of the present invention;

[0056] Figure 2is a structural schematic diagram of a dynamic parameter measurement system of a MEMS gyroscope provided by another embodiment of the present invention;

[0057] Figure 3 is a schematic diagram of the internal structure of a signal conditioning circuit provided by an embodiment of the present invention;

[0058] Figure 4 is a schematic diagram of spectrum analysis corresponding to a first output signal provided by an embodiment of the present invention;

[0059] Figure 5 is a waveform curve diagram of a second output signal provided by an embodiment of the present invention;. DETAILED DESCRIPTION

[0060] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0061] Under ideal working conditions, the driving structure inside the MEMS gyroscope is in a sinusoidal reciprocating motion state. When the angular velocity is non-zero, the detection mode will have an amplitude proportional to the angular velocity, and the same frequency as the driving mode frequency, with a phase difference of 90°. By measuring the amplitude of the detection mode, the magnitude of the input angular velocity can be obtained. When the angular velocity input is zero, the detection mode orthogonal to the driving mode will theoretically not have a sine wave with the same frequency as the driving mode frequency. But in fact, due to irrational factors such as process errors, residual stress, parasitic capacitance, etc., the detection mode of the MEMS gyroscope will have a sine wave with the same frequency as the driving mode frequency, but with a larger or smaller amplitude, and the detection mode amplitude is proportional to the driving mode amplitude.

[0062] Normally, the ratio of the amplitude of the detection mode to the amplitude of the driving mode in static state (i.e., zero angular velocity input state) is called the orthogonal coupling coefficient, which reflects the strength of the coupling of the amplitude of the driving mode to the amplitude of the detection mode. The size of the orthogonal coupling coefficient has a great influence on the zero bias and temperature coefficient of the MEMS gyroscope. The size of the orthogonal coupling coefficient, the gyroscope drive frequency, the deviation of the detection frequency from the design value and the distribution characteristics on the wafer also reflect the process control level of non-ideal factors such as process stress and process structure dimensional error.

[0063] Therefore, in the mass production of MEMS gyroscopes, it is necessary to measure the orthogonal coupling coefficient of the MEMS gyroscope, so as to realize the performance detection of the MEMS gyroscope, eliminate unqualified products, and reduce the subsequent waste of manpower and material resources.

[0064] Based on the idea of ​​accurately measuring the orthogonal coupling coefficient of a MEMS gyroscope, an embodiment of the present invention provides a dynamic parameter measurement system for a MEMS gyroscope, which generates a driving signal and a detection carrier signal by using a signal source, and superimposes the driving signal on the driving carrier signal by using a signal conditioning circuit, and applies the superimposed signal and the detection carrier signal to the MEMS gyroscope to be tested to drive the MEMS gyroscope to be tested, and then by collecting the first output signal of the intermediate plate of the MEMS gyroscope to be tested, the sum frequency signal and the difference frequency signal corresponding to the driving modal amplitude and the detection modal amplitude of the MEMS gyroscope to be tested can be analyzed, and then the orthogonal coupling coefficient can be obtained according to the amplitude of the sum frequency signal and the difference frequency signal. The embodiment of the present invention can not only realize the measurement of the orthogonal coupling coefficient, but also, by superimposing and modulating the driving signal on the driving carrier signal and applying the detection carrier signal at the same time, the amplitude of the driving mode and the amplitude of the detection mode can be modulated at high frequency, thereby effectively avoiding the influence of the driving modal frequency on the electrical coupling caused by the circuit parasitic parameters and the low-frequency noise on the test error, and improving the measurement accuracy of the orthogonal coupling coefficient.

[0065] In order to make the purpose, technical solutions and advantages of the present invention more clear, specific embodiments will be described below in conjunction with the accompanying drawings.

[0066] Figure 1 The structural schematic diagram of the dynamic parameter measurement system of the MEMS gyroscope provided by the embodiment of the present invention is described in detail as follows:

[0067] The dynamic parameter measurement system of the MEMS gyroscope mainly includes: a signal source, a signal conditioning circuit and a host computer.

[0068] The signal source is mainly used to: generate a driving signal based on the driving modal frequency of the MEMS gyroscope to be tested; and generate a detection carrier signal based on the detection modal frequency of the MEMS gyroscope to be tested.

[0069] Here, the driving signal may be a sinusoidal voltage signal having the same driving mode frequency as the MEMS gyroscope to be tested, and the detection carrier signal may be a sinusoidal voltage signal having the same detection mode frequency as the MEMS gyroscope to be tested.

[0070] In some embodiments, the mathematical expression of the driving signal can be expressed as: The mathematical expression for detecting the carrier signal can be expressed as: .

[0071] in, Represents the driving signal, represents the driving modal frequency, Indicates detection of carrier signal. Represents the detected modal frequency.

[0072] The signal conditioning circuit is mainly used to: superimpose the driving signal and the preset driving carrier signal, and input the superimposed signal to the driving electrode of the MEMS gyroscope to be tested; and input the detection carrier signal to the detection electrode of the MEMS gyroscope to be tested.

[0073] Here, the preset driving carrier signal can be expressed as .in, Represents the driving carrier signal, Here, the frequency of the driving carrier signal can be determined according to actual conditions, and is not specifically limited in the implementation of the present invention. For example, the frequency of the driving carrier signal can be any frequency value within the range of 10kHz to 30kHz.

[0074] In some embodiments, see Figure 2 The system also includes: a probe station and a probe card. The MEMS gyroscope to be tested is placed on the probe station, and the driving electrode, the detection electrode and the middle plate of the MEMS gyroscope to be tested are connected to the probe card.

[0075] See also Figure 3 The signal conditioning circuit is equipped with a signal superposition circuit and a differential circuit. The signal superposition circuit can and the preset driving carrier signal The superimposed and differential circuit can convert the superimposed signals into a first differential signal, and input the first differential signal to the driving electrodes D+ and D- of the MEMS gyroscope to be tested via the probe card.

[0076] The signal conditioning circuit can also detect the carrier signal The second differential signal is converted into a second differential signal, and the second differential signal is input to the detection electrodes S+ and S- of the MEMS to be tested via the probe card.

[0077] It should be noted that the drive signal After being applied to the driving electrode of the MEMS gyroscope under test, the driving mode of the MEMS gyroscope under test can be expressed as: The detection mode of the MEMS gyroscope to be tested can be expressed as: .

[0078] here, represents the amplitude of the driving mode of the MEMS gyroscope to be tested, represents the amplitude of the detection mode of the MEMS gyroscope to be tested, Represents the phase difference between the detection mode and the driving mode. is close to 0, and the embodiment of the present invention ignores the phase difference.

[0079] The driving mode and detection mode of the MEMS gyroscope to be tested are modulated by the driving carrier signal and the detection carrier signal respectively, which can effectively avoid the influence of the electrical coupling caused by the driving mode frequency in the circuit parasitic parameters and the low-frequency noise on the test error, thereby effectively improving the measurement accuracy.

[0080] The host computer collects the first output signal of the middle electrode plate of the MEMS gyroscope to be tested through the signal conditioning circuit, and performs spectrum analysis on the first output signal to obtain a first sum frequency signal and a first difference frequency signal corresponding to the amplitude of the driving mode of the MEMS gyroscope to be tested, as well as a second sum frequency signal and a second difference frequency signal corresponding to the amplitude of the detection mode of the MEMS gyroscope to be tested, and determines the orthogonal coupling coefficient of the MEMS gyroscope to be tested based on the amplitude of the first sum frequency signal, the amplitude of the second sum frequency signal, the amplitude of the first difference frequency signal, and the amplitude of the second difference frequency signal.

[0081] In some embodiments, see Figure 2 and Figure 3 The system also includes an acquisition card. The signal conditioning circuit also has an I / V conversion circuit inside, which is used to convert the current signal into a voltage signal.

[0082] The signal conditioning circuit collects the current signal output by the middle plate of the MEMS gyroscope to be tested via the probe card, converts the current signal into a voltage signal, obtains a first output signal, and inputs the first output signal to the host computer via the acquisition card.

[0083] Here, the first output signal is a time domain signal. The host computer can perform Fourier analysis on the first output signal to convert the time domain signal into a frequency domain signal, and perform spectrum analysis to obtain a first sum frequency signal, a first difference frequency signal, a second sum frequency signal, and a second difference frequency signal. Figure 4 By converting the first output signal into a frequency domain signal and performing spectrum analysis, the first sum frequency signal in which the amplitude of the driving mode is modulated by the driving carrier signal can be obtained. and the first difference frequency signal , and the amplitude of the detection mode is modulated by the detection carrier signal of the second sum frequency signal and the second difference frequency signal .

[0084] In some embodiments, the host computer can Determine the orthogonal coupling coefficient of the MEMS gyroscope to be tested;

[0085] in, represents the orthogonal coupling coefficient, represents the amplitude of the second sum frequency signal, represents the amplitude of the second difference frequency signal, represents the amplitude of the first sum-frequency signal, Indicates the amplitude of the first difference frequency signal.

[0086] Compared with the prior art, the embodiment of the present invention generates a driving signal and a detection carrier signal based on the driving modal frequency and the detection modal frequency of the MEMS gyroscope to be tested by using a signal source, then superimposes the driving signal on the driving carrier signal by using a signal conditioning circuit, and applies the superimposed signal and the detection carrier signal to the MEMS gyroscope to be tested to drive the MEMS gyroscope to be tested, and then by collecting the first output signal of the intermediate plate of the MEMS gyroscope to be tested, the sum frequency signal and the difference frequency signal corresponding to the driving modal amplitude and the detection modal amplitude of the MEMS gyroscope to be tested can be analyzed, and then the orthogonal coupling coefficient can be obtained according to the amplitude of the sum frequency signal and the difference frequency signal. The embodiment of the present invention can not only realize the measurement of the orthogonal coupling coefficient, but also, by superimposing and modulating the driving signal on the driving carrier signal and applying the detection carrier signal at the same time, the amplitude of the driving mode and the amplitude of the detection mode can be modulated at high frequency, thereby effectively avoiding the influence of the driving modal frequency on the electrical coupling caused by the circuit parasitic parameters and the low-frequency noise on the test error, and improving the measurement accuracy of the orthogonal coupling coefficient.

[0087] The above embodiment mainly introduces a specific method for measuring the orthogonal coupling coefficient of the MEMS gyroscope to be tested based on the driving modal frequency and the detection modal frequency of the MEMS gyroscope to be tested. The following is a specific introduction to the measurement method of the driving modal frequency and the detection modal frequency.

[0088] When measuring the driving modal frequency of the MEMS gyroscope to be tested, the signal source is mainly used to: generate a preset sweep frequency signal, apply the sweep frequency signal to the driving electrode of the MEMS gyroscope to be tested via a signal conditioning circuit, and cancel the sweep frequency signal after maintaining it for a preset time.

[0089] The host computer is mainly used to collect the second output signal of the middle plate of the MEMS gyroscope to be tested through the signal conditioning circuit, and determine the driving mode frequency of the MEMS gyroscope to be tested based on the second output signal and the natural decay oscillation theoretical expression of the amplitude of the driving mode of the MEMS gyroscope.

[0090] Here, the signal source is used to generate a sweep frequency signal within a preset frequency range, and transmit the sweep frequency signal to a signal conditioning circuit. The signal conditioning circuit converts the sweep frequency signal into a differential signal and applies it to the drive electrode of the MEMS gyroscope to be tested via a probe card.

[0091] The lower frequency limit value of the preset frequency range is less than the design value of the resonant frequency of the MEMS gyroscope to be tested, and the upper frequency limit value of the preset frequency range is greater than the design value of the resonant frequency of the MEMS gyroscope to be tested.

[0092] When the sweep signal is applied to the driving electrode of the MEMS gyroscope to be tested and maintained for a preset time, the signal source cancels the sweep signal, so that the MEMS gyroscope to be tested oscillates and decays naturally under the action of the electrostatic force. At this time, the signal conditioning circuit collects the current signal generated by the middle plate of the MEMS gyroscope to be tested through the probe card, amplifies the current signal and converts it into a voltage signal to obtain a second output signal. The second output signal here can be used to characterize the natural decay oscillation of the amplitude of the driving mode of the MEMS gyroscope to be tested.

[0093] The waveform curve of the second output signal of the MEMS gyroscope to be tested is as follows: Figure 5 As shown, the theoretical expression corresponding to the waveform curve is: .

[0094] in, A naturally decaying oscillation signal representing the amplitude of the driving mode of the MEMS gyroscope to be tested, represents the damping ratio of the MEMS gyroscope to be tested, represents the driving modal frequency of the MEMS gyroscope to be tested, Indicates time, Indicates the damped oscillation frequency of the MEMS gyroscope to be tested.

[0095] The embodiment of the present invention can obtain the damped oscillation frequency of the MEMS gyroscope to be tested by performing spectrum analysis and image curve fitting on the second output signal. and damping ratio .

[0096] Among them, the damped oscillation frequency of the MEMS gyroscope to be tested and the driving modal frequency The mathematical expression between is: .

[0097] Since the damping ratio of the MEMS gyroscope to be tested is , usually, you can make , thereby determining the driving modal frequency of the MEMS gyroscope to be tested according to the damped oscillation frequency of the MEMS gyroscope to be tested.

[0098] On the basis of determining the damping ratio of the MEMS gyroscope to be tested, the host computer may also determine the quality factor of the MEMS gyroscope to be tested based on the damping ratio of the MEMS gyroscope to be tested.

[0099] In some embodiments, the host computer can Determine the quality factor of the MEMS gyroscope to be tested;

[0100] in, represents the quality factor of the MEMS gyroscope to be tested, Indicates the damping ratio of the MEMS gyroscope to be tested.

[0101] When measuring the detection modal frequency of the MEMS gyroscope to be tested, the signal source is mainly used to: generate a preset sweep frequency signal, apply the sweep frequency signal to the detection electrode of the MEMS gyroscope to be tested via the signal conditioning circuit, and cancel the sweep frequency signal after maintaining the preset time length;

[0102] The host computer is mainly used for: collecting the third output signal of the middle plate of the MEMS gyroscope to be tested via the signal conditioning circuit, and determining the detection mode frequency of the MEMS gyroscope to be tested based on the third output signal and the natural decay oscillation theoretical expression of the amplitude of the detection mode of the MEMS gyroscope to be tested.

[0103] Here, the third output signal is used to characterize the natural decay oscillation of the amplitude of the detection mode of the MEMS gyroscope to be tested. The theoretical expression of the natural decay oscillation of the amplitude of the detection mode of the MEMS gyroscope to be tested is: ;

[0104] in, A naturally decaying oscillation signal representing the amplitude of the detection mode of the MEMS gyroscope to be tested, represents the damping ratio of the MEMS gyroscope to be tested, represents the detection modal frequency of the MEMS gyroscope to be tested, Indicates time, Indicates the damped oscillation frequency of the MEMS gyroscope to be tested.

[0105] The embodiment of the present invention performs spectrum analysis and image curve fitting on the waveform curve of the third output signal, thereby determining the detection modal frequency of the MEMS gyroscope to be tested.

[0106] The method for determining the detection modal frequency is the same as the method for determining the driving modal frequency described above. For details, please refer to the method for determining the driving modal frequency described above, which will not be described in detail here.

[0107] In addition, after completing the dynamic parameter measurement of the current MEMS gyroscope to be tested, the host computer can also control the movement of the probe station to achieve the purpose of switching the next MEMS gyroscope to be tested.

[0108] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A dynamic parameter measurement system for a MEMS gyroscope, characterized in that: include: Signal source, signal conditioning circuit and host computer; Signal source for: generating a driving signal based on a driving modal frequency of the MEMS gyroscope to be tested; Generating a detection carrier signal based on the detection modal frequency of the MEMS gyroscope to be tested; Signal conditioning circuits for: Superimposing the driving signal and a preset driving carrier signal, and inputting the superimposed signal to the driving electrode of the MEMS gyroscope to be tested; Inputting the detection carrier signal to the detection electrode of the MEMS gyroscope to be tested; The host computer is used for: The first output signal of the intermediate plate of the MEMS gyroscope to be tested is collected via the signal conditioning circuit, and the first output signal is subjected to spectrum analysis to obtain a first sum frequency signal and a first difference frequency signal corresponding to the amplitude of the driving mode of the MEMS gyroscope to be tested, and a second sum frequency signal and a second difference frequency signal corresponding to the amplitude of the detection mode of the MEMS gyroscope to be tested; Determining the orthogonal coupling coefficient of the MEMS gyroscope to be tested based on the amplitude of the first sum frequency signal, the amplitude of the second sum frequency signal, the amplitude of the first difference frequency signal, and the amplitude of the second difference frequency signal; The host computer is used for: according to Determining the orthogonal coupling coefficient of the MEMS gyroscope to be tested; in, represents the orthogonal coupling coefficient, represents the amplitude of the second sum frequency signal, represents the amplitude of the second difference frequency signal, represents the amplitude of the first sum-frequency signal, Indicates the amplitude of the first difference frequency signal.

2. The dynamic parameter measurement system of a MEMS gyroscope according to claim 1, characterized in that: The signal source is also used for: Generate a preset sweep frequency signal, apply the sweep frequency signal to the drive electrode of the MEMS gyroscope to be tested via the signal conditioning circuit, and cancel the sweep frequency signal after maintaining the preset time length; The host computer is also used for: The second output signal of the intermediate plate of the MEMS gyroscope to be tested is collected via the signal conditioning circuit; the second output signal is used to characterize the natural attenuation oscillation of the amplitude of the driving mode of the MEMS gyroscope to be tested; Determine the driving modal frequency of the MEMS gyroscope to be tested based on the second output signal and a natural decay oscillation theoretical expression of the amplitude of the driving mode of the MEMS gyroscope to be tested; The natural decay oscillation theoretical expression of the amplitude of the driving mode of the MEMS gyroscope to be tested is: ; in, A naturally decaying oscillation signal representing the amplitude of the driving mode of the MEMS gyroscope to be tested, represents the damping ratio of the MEMS gyroscope to be tested, represents the driving modal frequency of the MEMS gyroscope to be tested, Indicates time, Indicates the damped oscillation frequency of the MEMS gyroscope to be tested.

3. The dynamic parameter measurement system of a MEMS gyroscope according to claim 2, characterized in that: The host computer is also used for: Determining the damping ratio of the MEMS gyroscope to be tested based on the second output signal and a natural decay oscillation theoretical expression of the amplitude of the driving mode of the MEMS gyroscope to be tested; The quality factor of the MEMS gyroscope to be tested is determined based on the damping ratio of the MEMS gyroscope to be tested.

4. The dynamic parameter measurement system of a MEMS gyroscope according to claim 3, characterized in that: The host computer is used for: according to Determining the quality factor of the MEMS gyroscope to be tested; in, represents the quality factor of the MEMS gyroscope to be tested, represents the damping ratio of the MEMS gyroscope to be tested.

5. The dynamic parameter measurement system of a MEMS gyroscope according to claim 1, characterized in that: The signal source is also used for: Generate a preset sweep frequency signal, apply the sweep frequency signal to the detection electrode of the MEMS gyroscope to be tested via the signal conditioning circuit, and cancel the sweep frequency signal after maintaining the preset time length; The host computer is also used for: The third output signal of the intermediate plate of the MEMS gyroscope to be tested is collected via the signal conditioning circuit; the third output signal is used to characterize the natural attenuation oscillation of the amplitude of the detection mode of the MEMS gyroscope to be tested; Determine the detection modal frequency of the MEMS gyroscope to be tested based on the third output signal and a natural decay oscillation theoretical expression of the amplitude of the detection mode of the MEMS gyroscope to be tested; The natural decay oscillation theoretical expression of the amplitude of the detection mode of the MEMS gyroscope to be tested is: ; in, A naturally decaying oscillation signal representing the amplitude of the detection mode of the MEMS gyroscope to be tested, represents the damping ratio of the MEMS gyroscope to be tested, represents the detection modal frequency of the MEMS gyroscope to be tested, Indicates time, Indicates the damped oscillation frequency of the MEMS gyroscope to be tested.

6. The dynamic parameter measurement system of a MEMS gyroscope according to claim 1, characterized in that: The system further comprises: a probe station and a probe card; the MEMS gyroscope to be tested is placed on the probe station, and the driving electrode, the detection electrode and the intermediate plate of the MEMS gyroscope to be tested are connected to the probe card; The signal conditioning circuit is used to: Superimposing the driving signal and a preset driving carrier signal, converting the superimposed signal into a first differential signal, and inputting the first differential signal to the driving electrode of the MEMS gyroscope to be tested via the probe card; The detection carrier signal is converted into a second differential signal, and the second differential signal is input to the detection electrode of the MEMS to be tested via the probe card.

7. The dynamic parameter measurement system of a MEMS gyroscope according to claim 6, characterized in that: The system also includes a capture card; The signal conditioning circuit is used to: Collecting a current signal output by the middle plate of the MEMS gyroscope to be tested via the probe card, and converting the current signal into a voltage signal to obtain a first output signal; The first output signal is input to the host computer via the acquisition card.

8. The dynamic parameter measurement system of a MEMS gyroscope according to claim 1, characterized in that: The mathematical expression of the driving signal is: ; The mathematical expression of the detected carrier signal is: ; in, represents the driving signal, represents the driving modal frequency, represents the detected carrier signal, represents the detected modal frequency.

9. The dynamic parameter measurement system of a MEMS gyroscope according to claim 1, characterized in that: The mathematical expression of the preset driving carrier signal is: ; in, Represents the driving carrier signal, Indicates the frequency of the driving carrier signal. The frequency of the driving carrier signal is any frequency value in the range of 10kHz~30kHz.

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