Adaptive phase alignment circuit, debugging method and gyroscope measurement and control circuit

Abstract

An adaptive phase alignment circuit includes: a digitally controlled phase shifter for adjusting the phase of a first signal; a phase-locked loop for performing phase-locked filtering on the phase-shifted first signal to obtain a second signal from the first signal; a phase detector for comparing the phases of the second signal and a third signal to obtain a phase difference between the second and third signals, wherein a specific phase alignment relationship exists between the second and third signals; a signal conversion module for converting the phase difference into a digital quantity; an adder for calculating a phase adjustment control variable for the first signal; and, based on the phase adjustment, causing the digitally controlled phase shifter to adjust the phase of the first signal to align with the third signal. Based on this circuit, the present disclosure also provides a gyroscope measurement and control circuit that uses an adaptive phase alignment circuit to align the gyroscope's quadrature error with its carrier signal by 90 degrees, thereby facilitating a coherent demodulator to accurately extract the Coriolis shift. The Coriolis shift can then be used to calculate the gyroscope's angular velocity.

Description

Technical Field

[0001] The present disclosure relates to the technical field of gyroscopes, and in particular to an adaptive phase alignment circuit, a debugging method, and a gyroscope measurement and control circuit. Background Art

[0002] Compared with traditional gyroscopes, silicon MEMS gyroscopes have significant advantages such as low cost, low power consumption, small size, light weight and high reliability. They have been widely used in consumer electronics, automobiles and industrial control.

[0003] Typically, a MEMS gyroscope is a vibrating gyroscope that senses angular velocity based on the Coriolis effect. If the gyroscope is driven to stable oscillation on the X-axis and a rotational angular velocity is input on the Z-axis, a Coriolis shift is generated on the Y-axis (the detection axis). Detecting this shift provides the magnitude of the input angular velocity. To improve the MEMS gyroscope's interference resistance, it typically operates in the low-pass region rather than the modal matching region, resulting in an extremely weak Coriolis shift. Due to non-idealities in the micromachining process, the MEMS gyroscope's driven displacement deviates from the X-axis by an angle, causing a component of the driven displacement to couple to the detection axis, resulting in quadrature error. The phase of the quadrature error lags the Coriolis shift by 90 degrees, and the magnitude of the quadrature error is much greater than the Coriolis shift. Coherent demodulation is typically used to extract the Coriolis shift for angular velocity detection. Summary of the Invention

[0004] The present disclosure provides an adaptive phase alignment circuit, a debugging method, and a gyroscope measurement and control circuit to solve the above technical problems.

[0005] The present disclosure provides an adaptive phase alignment circuit, comprising: a digitally controlled phase shifter for adjusting the phase of a first signal; a phase-locked loop for performing phase-locked filtering on the phase-shifted first signal to obtain a second signal from the first signal; a phase detector for comparing the phases of the second signal and a third signal to obtain a phase difference between the second signal and the third signal, wherein a specific phase alignment relationship exists between the second signal and the third signal; a signal conversion module for converting the phase difference into a digital quantity; an adder for calculating the sum of the digital quantity and a preset digital quantity to obtain a phase adjustment control quantity of the first signal, and transmitting the phase adjustment control quantity to the digitally controlled phase shifter so that the digitally controlled phase shifter adjusts the phase of the first signal to form a 90-degree phase alignment with the third signal.

[0006] Optionally, the digitally controlled phase shifter includes: an operational amplifier, a first resistor, a second resistor, and a digitally controlled pole adjustment sub-circuit; one end of the first resistor is connected to the input end of the first signal, and the other end is connected to the negative input end of the operational amplifier; one end of the second resistor is connected to the negative input end of the operational amplifier, and the other end is connected to the output end of the operational amplifier; the first port of the digitally controlled pole adjustment sub-circuit is connected to the input end of the first signal, the second port is connected to the positive input end of the operational amplifier, and the third port is connected to the external digital signal input end.

[0007] Optionally, the digitally controlled pole adjustment sub-circuit includes at least a digitally controlled adjustable resistor or a digitally controlled adjustable capacitor, and the digitally controlled adjustable resistor or the digitally controlled adjustable capacitor is controlled by the external digital signal and is used to adjust the pole position of the digitally controlled phase shifter so that the phase of the first signal changes accordingly.

[0008] Optionally, the signal conversion module includes: a phase detector for converting the phase difference into a voltage control signal; a charge pump for converting the voltage control signal into a current signal; a loop filter for converting the current signal into a voltage signal; and an analog-to-digital converter for converting the voltage signal into the digital quantity.

[0009] Optionally, the phase-locked loop is provided with an input signal threshold, and only a portion of the first signal that is higher than the input signal threshold is input into the phase-locked loop.

[0010] Optionally, after the phase-locked loop performs phase-locked filtering on the first signal, the output second signal is in phase with the first signal.

[0011] A second aspect of the present disclosure provides an adaptive phase alignment circuit debugging method, which is applied to the adaptive phase alignment circuit as described in the first aspect, including: S1, disconnecting the connection line between the loop filter and the analog-to-digital converter; S2, fixing the voltage of the analog-to-digital converter to Vref / 2, where Vref is the input voltage range of the analog-to-digital converter; S3, inputting a first signal to the digitally controlled phase shifter; S4, adjusting a preset digital quantity so that the second output signal of the phase-locked loop 212 is phase-aligned with the third signal by approximately 90 degrees; S5, fixing the preset digital quantity; S6, connecting the loop filter and the analog-to-digital converter to complete the debugging.

[0012] Another aspect of the present disclosure provides a gyroscope measurement and control circuit, including the adaptive phase alignment circuit as described in the first aspect, including: a drive circuit for driving the gyroscope to operate and obtain a carrier signal required by the coherent demodulator of the gyroscope; a detection circuit, including the adaptive phase alignment circuit, for aligning the quadrature error signal generated during the operation of the gyroscope with the carrier signal by 90 degrees, so that the Coriolis shift signal of the gyroscope can smoothly pass through the coherent demodulator, while the quadrature error signal of the gyroscope cannot pass through the coherent demodulator, thereby completing angular velocity detection.

[0013] Optionally, the detection circuit includes: a first C / V conversion circuit, used to convert the differential detection signal generated during the operation of the gyroscope into a first signal, wherein the first signal at least includes the orthogonal error signal and the Coriolis shift signal; an adaptive phase alignment circuit, used to adjust the phase of the orthogonal error signal so that the phase of the orthogonal error signal is aligned with the carrier signal by 90 degrees; a coherent demodulator, used to coherently demodulate the first signal after the phase shift of the orthogonal error signal and the carrier signal to obtain the Coriolis shift signal; and a filter conversion circuit, used to filter the Coriolis shift signal and convert it into a required signal type.

[0014] Optionally, the filtering and conversion circuit includes: a low-pass filter converter for filtering out noise in the Coriolis shift signal; and a first analog-to-digital converter for converting the Coriolis shift signal into a digital signal, wherein the digital signal is used to calculate the angular velocity of the gyroscope.

[0015] Optionally, the driving circuit includes: a second C / V conversion circuit, used to convert the capacitance change of the gyroscope into an electrical signal; a phase-locked loop, used to phase-lock and filter the electrical signal to obtain the carrier signal, and the carrier signal is in phase with the electrical signal; an amplitude detector, used to detect the amplitude of the electrical signal; a comparator, used to compare the amplitude with a preset amplitude to obtain an adjustment amount of the carrier signal; and a variable gain amplifier, used to amplify the carrier signal according to the adjustment amount and output it to the gyroscope. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] For a more complete understanding of the present disclosure and its advantages, reference will now be made to the following description taken in conjunction with the accompanying drawings, in which:

[0017] Figure 1 A schematic diagram of a disclosed MEMS vibrating gyroscope circuit is schematically shown;

[0018] Figure 2 The following schematically shows a schematic diagram of a gyroscope measurement and control circuit provided by an embodiment of the present disclosure;

[0019] Figure 3 A schematic diagram of a digitally controlled phase shifter provided by an embodiment of the present disclosure is schematically shown;

[0020] Figure 4 A schematic diagram of a digitally controlled phase shifter provided by an embodiment of the present disclosure is schematically shown;

[0021] Figure 5 A schematic diagram of a digitally controlled phase shifter provided by an embodiment of the present disclosure is schematically shown. DETAILED DESCRIPTION

[0022] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present disclosure. In the detailed description below, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0023] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise," "include," etc. used herein indicate the presence of the features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0024] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0025] The phase relationship between the driving displacement and the Coriolis shift in a MEMS vibratory gyroscope depends on the relationship between the resonant frequencies of the gyroscope's driving and sensing modes. Different phase relationships exist when the driving mode resonant frequency is greater than, less than, or equal to the sensing mode resonant frequency. However, the phase relationship between the quadrature error and the Coriolis shift is constant and unaffected by the relationship between the gyroscope's two modal resonant frequencies. This fact allows the design of a coherent demodulation system based on quadrature error alignment to obtain the Coriolis shift.

[0026] like Figure 1As shown, the system's drive circuit consists of a MEMS gyroscope, a C / V conversion circuit, a filter, a phase shifter, a phase-locked loop (PLL), a resistor divider, and a filter. The drive circuit's task is to drive the device to a stable oscillation state, preparing for subsequent detection of input angular velocity information. In the drive circuit, because the PLL output leads the input by 90 degrees, a phase shifter is added after the C / V conversion circuit. Because the C / V conversion circuit's output contains significant broadband noise, a filter is added after this circuit. To ensure safe device operation and a better output spectrum, the PLL output undergoes a resistor divider and low-pass filtering. The system's detection circuit consists of a C / V conversion circuit, an adjustable phase shifter, a mixer, a low-pass filter, and an analog-to-digital converter. The mixer's carrier comes from the drive circuit's PLL rather than the C / V conversion circuit's output. This produces a cleaner demodulated carrier and decouples the carrier from the drive displacement. By adjusting the detection circuit's adjustable phase shifter, the quadrature error phase lags the carrier by 90 degrees, automatically achieving in-phase alignment between the Coriolis shift and the carrier. Given that the magnitude of quadrature error is much greater than the Coriolis shift, this system achieves phase alignment based on quadrature error rather than Coriolis shift. This system enables the MEMS gyroscope to achieve proper actuation and detection, with a scale factor of 1.415 mV / ° / s and bias instability of 108° / h.

[0027] The zero-bias instability of the MEMS gyroscope system is relatively high, and its circuit system also has some problems: (1) The stability of the drive displacement amplitude is relatively low, and there is no direct amplitude control of the drive displacement; (2) The drive circuit contains filters and phase shifters, which increases the circuit complexity and introduces electrical noise; (3) The orthogonal error of the detection circuit has phase jitter, and the phase alignment accuracy is not high, resulting in poor demodulation effect; (4) The use of manual observation to determine whether the phase is aligned and the phase shift of the phase shifter are manually adjusted, which easily causes phase alignment errors. In addition, due to factors such as temperature, this error will creep, which deteriorates the performance of coherent demodulation.

[0028] Figure 2 The schematic diagram of the gyroscope measurement and control circuit provided by the embodiment of the present disclosure is schematically shown. In this circuit, an adaptive phase alignment circuit 210 provided by the embodiment of the present disclosure is included.

[0029] like Figure 2 As shown, an embodiment of the present disclosure provides an adaptive phase alignment circuit 210 , including: a digitally controlled phase shifter 211 , a phase-locked loop 212 , a phase detector 213 , a signal conversion module 214 , and an adder 215 .

[0030] The digitally controlled phase shifter 211 is configured to adjust the phase of the first signal.

[0031] The phase-locked loop 212 is configured to perform phase-locked filtering on the phase-shifted first signal to obtain a second signal from the first signal.

[0032] The phase detector 213 is used to compare the phases of the second signal and the third signal to obtain a phase difference between the second signal and the third signal. A specific phase alignment relationship exists between the second signal and the third signal.

[0033] The signal conversion module 214 is configured to convert the phase difference into a digital value.

[0034] The adder 215 is used to calculate the sum of the digital quantity and the preset digital quantity to obtain the phase adjustment control quantity of the first signal, and transmit the phase adjustment control quantity to the digitally controlled phase shifter 211, so that the digitally controlled phase shifter 211 adjusts the phase of the first signal to be aligned with the third signal.

[0035] In the embodiment of the present disclosure, assuming that the second signal is the orthogonal error of the gyroscope and the third signal is the demodulated carrier of the gyroscope, the adaptive phase alignment circuit 210 can be used to achieve a 90° phase alignment between the orthogonal error and the demodulated carrier, so as to separate the Coriolis shift of the gyroscope from the demodulated carrier.

[0036] Optionally, the first signal and the third signal may be various types of signals such as voltage signals, current signals, differential signals, etc.

[0037] In the embodiment of the present disclosure, the digitally controlled phase shifter 211 includes: an operational amplifier, a first resistor, a second resistor, and a digitally controlled pole adjustment sub-circuit.

[0038] Among them, one end of the first resistor is connected to the input end of the first signal, and the other end is connected to the negative input end of the operational amplifier; one end of the second resistor is connected to the negative input end of the operational amplifier, and the other end is connected to the output end of the operational amplifier; the first port of the digital control pole adjustment sub-circuit is connected to the input end of the first signal, the second port is connected to the positive input end of the operational amplifier, and the third port is connected to the external digital signal input end.

[0039] The digitally controlled pole adjustment subcircuit includes at least a digitally controlled adjustable resistor or a digitally controlled adjustable capacitor, which is controlled by the external digital signal and is used to adjust the pole position of the digitally controlled phase shifter so that the phase of the first signal changes accordingly.

[0040] Figure 3 A schematic diagram of a digitally controlled phase shifter 211 provided by an embodiment of the present disclosure is schematically shown.

[0041] like Figure 3As shown, AMP represents an operational amplifier, R4 represents a first resistor, R6 represents a second resistor, R5 represents a digitally controlled adjustable resistor, and C3 represents a grounding capacitor, which constitutes a digitally controlled pole-adjusting sub-circuit. i Indicates the first signal, V o The phase shifter is based on an operational amplifier AMP and utilizes negative feedback of R4 and R6, a digitally controlled adjustable resistor R5, and a fixed capacitor C3 to achieve a 0° to -180° hysteresis phase shift.

[0042] When the feedback resistors R4 and R6 are equal, the transfer function of the phase shifter is:

[0043]

[0044] Figure 4 and Figure 5 A variation of a digitally controlled phase shifter 211 is provided for each embodiment of the present disclosure, wherein: Figure 4 The digital control pole adjustment sub-circuit in the circuit is composed of resistor R5 and digital control adjustable capacitor C3. Figure 5 The digital control regulating subcircuit is composed of a digital control adjustable resistor and a digital control adjustable capacitor. Figures 3-5 The three types of digitally controlled phase shifters 211 shown can all be controlled by external digital signals to adjust the digitally controlled adjustable resistors or digitally controlled adjustable capacitors inside the digitally controlled phase shifter 211 so as to change the poles of the digitally controlled phase shifter 211, thereby achieving phase shifting of different phases of the first signal input to the digitally controlled phase shifter 211.

[0045] In the embodiment of the present disclosure, the signal conversion module 214 includes: a charge pump 2141 , a loop filter 2142 , and an analog-to-digital converter 2143 .

[0046] The charge pump 2141 is used to convert the phase difference into a current signal.

[0047] The loop filter 2142 is used to convert the current signal into a voltage signal.

[0048] The analog-to-digital converter 2143 is used to convert the voltage signal into a digital value.

[0049] In the disclosed embodiment, a digitally controlled phase shifter 211 is used to adjust the first signal. After the phase-shifted first signal is subjected to phase-locked filtering by a phase-locked loop 212 and the phase difference is calculated by a phase detector 213, the phase difference is converted into a digital signal by a signal conversion module 214 before being fed back to the digitally controlled phase shifter 211. This signal is used to adjust the digitally controlled phase shifter 211 and, accordingly, adjust the phase of the second signal contained in the first signal. Through this feedback mechanism, the second signal and the third signal are aligned by 90 degrees. Therefore, in this process, the phase difference signal should be converted into a digital signal by a charge pump 2141, a loop filter 2142, an analog-to-digital converter 2143, etc., according to actual needs. The analog-to-digital converter 2143 can be a high-precision ADC with 16 bits or more to cooperate with the digitally controlled phase shifter to achieve high-precision adjustment of the phase shift of the first signal.

[0050] In the disclosed embodiment, the phase-locked loop 212 is configured with an input signal threshold, allowing only the portion of the first signal above the input signal threshold to be input into the phase-locked loop 212. Taking the first signal, a differential detection signal from a gyroscope, as an example, this signal includes signals such as quadrature error, Coriolis shift, and noise. Because the amplitude of the Coriolis shift is much smaller than the quadrature error, the input signal threshold of the phase-locked loop 212 is set at a higher potential, allowing the phase-locked loop 212 to capture and lock only the quadrature error, thereby obtaining a second signal. The phase detector 213 then compares the quadrature error with the carrier (i.e., the third signal) to achieve a 90-degree phase alignment between the quadrature error and the carrier, thereby obtaining the gyroscope's Coriolis shift. The phase-locked loop 212 reduces the phase jitter of the quadrature error, improves the accuracy of phase alignment, and enhances the performance of coherent demodulation.

[0051] In the disclosed embodiment, after the phase-locked filtering process on the first signal, the phase-locked loop 212 outputs a second signal that is in phase with the first signal. Thus, the phase-locked loop 212 can extract and filter the quadrature error without changing its phase, significantly improving the accuracy of phase alignment.

[0052] The adaptive phase alignment circuit 210 provided in the embodiments of the present disclosure can be applied to align the quadrature error and carrier phase of a vibratory gyroscope. By using a digitally controlled phase shifter to adjust the quadrature error phase, the circuit achieves higher precision and stronger coherence adjustment performance. It is understood that the adaptive phase alignment circuit 210 provided in the present disclosure is not limited to this application and can also be applied to other application scenarios requiring phase calibration and phase alignment.

[0053] The embodiment of the present disclosure further provides a debugging method applied to the adaptive phase alignment circuit 210 , including steps S1 to S2 .

[0054] S1, disconnect the connection line between the loop filter 2142 and the analog-to-digital converter 2143.

[0055] S2, fixing the voltage of the analog-to-digital converter 2143 to Vref / 2, where Vref is the range of the input voltage of the analog-to-digital converter 2143.

[0056] S3, inputting a first signal to the digitally controlled phase shifter.

[0057] S4, adjusting the preset digital value so that the second signal output by the phase-locked loop 212 and the third signal are aligned in phase by approximately 90 degrees.

[0058] S5, fixed preset digital quantity.

[0059] S6, connect the loop filter 2142 and the analog-to-digital converter 2143 to complete the debugging.

[0060] In steps S1-S4, since the connection line between loop filter 2142 and analog-to-digital converter 2143 is disconnected, adaptive phase alignment circuit 210 is an open-loop circuit. The output voltage range of loop filter 2142 is 0-Vref, and the input signal range of analog-to-digital converter 2143 is also 0-Vref. By fixing the voltage of analog-to-digital converter 2143 to Vref / 2, when the second and third output signals of phase-locked loop 212 are approximately 90 degrees aligned in phase, the output DC voltage of loop filter 2142 is also approximately Vref / 2, which can be used to achieve phase calibration between the second and third signals. Adjusting the preset digital value based on the voltage value of analog-to-digital converter 2143 being Vref / 2 maximizes the adjustable range of loop filter 2142's output voltage, thereby maximizing the dynamic adjustment range of the adaptive feedback loop. After fixing the preset digital quantity, the loop filter 2142 and the analog-to-digital converter 2143 are connected to restore the adaptive phase alignment circuit to a closed loop. The adaptive phase alignment circuit 210 can automatically achieve precise 90-degree phase alignment of the second signal and the third signal, and can track and align in real time according to environmental changes.

[0061] It should be noted that this method is not only applicable to achieving 90-degree phase alignment between the second signal and the third signal, but can also achieve phase alignment of different degrees between the second signal and the third signal according to actual conditions.

[0062] like Figure 2 As shown, the present disclosure provides a gyroscope measurement and control circuit, which includes the detection circuit 220 of the adaptive phase alignment circuit 210 as described above, and a driving circuit 230 .

[0063] The driving circuit 230 is used to drive the gyroscope to work and obtain the carrier signal of the coherent demodulator of the gyroscope.

[0064] The detection circuit 220 includes an adaptive phase alignment circuit 210 for performing 90-degree phase alignment between the quadrature error signal generated during the operation of the gyroscope and the carrier signal so that the coherent demodulator can accurately extract the Coriolis shift signal.

[0065] In the disclosed embodiment, the drive circuit 230 is used to drive the gyroscope to operate stably and simultaneously obtain the carrier signal required by the gyroscope's coherent demodulator. Furthermore, the carrier signal is used to calibrate the gyroscope's quadrature error by 90 degrees in the detection circuit 220. The carrier signal is the third signal input to the adaptive phase alignment circuit 210, and the differential detection signal or single-ended detection signal of the gyroscope detected by the detection circuit 220 is the first signal.

[0066] It can be understood that, in order to adapt to the conversion of signal types, the differential detection signal or single-ended detection signal of the gyroscope detected by the detection circuit 220 can be converted into a signal type acceptable to the adaptive phase alignment circuit 210 .

[0067] See Figure 2 The detection circuit 220 includes: a first C / V conversion circuit 221, an adaptive phase alignment circuit 210, a coherent demodulator 222, and a filter conversion circuit 223.

[0068] The first C / V conversion circuit 221 is used to convert the differential detection signal generated during the operation of the gyroscope into a first signal, where the first signal at least includes an orthogonal error signal and a Coriolis shift signal.

[0069] The adaptive phase alignment circuit 210 is used to adjust the phase of the quadrature error signal so that the phase of the quadrature error signal is aligned with the carrier signal by 90 degrees.

[0070] The coherent demodulator 222 is configured to coherently demodulate the first signal after the quadrature error signal is phase-shifted with the carrier signal to obtain a Coriolis shift signal.

[0071] The filter conversion circuit 223 is used to filter the Coriolis shift signal and convert it into a required signal type.

[0072] It is understandable that the gyroscope signal obtained by the first C / V conversion circuit 221 is not limited to differential detection signals or single-ended detection signals, but may also include other signal information such as orthogonal error signals and Coriolis shift signals.

[0073] Optionally, each module in the detection circuit 220 may be implemented using a digital circuit.

[0074] In the disclosed embodiment, the first C / V conversion circuit 221 converts the differential detection signal obtained from the gyroscope into a first signal. The adaptive phase alignment circuit 210 achieves 90° phase alignment between the quadrature error signal and the carrier signal, enabling the coherent demodulator 222 to separate the Coriolis shift signal from the first signal. The filter conversion circuit 223 filters out noise in the Coriolis shift signal and converts it into the signal type required for the next step, for example, into a digital signal for calculating the gyroscope angular velocity.

[0075] See Figure 2 In the embodiment of the present disclosure, the filtering and converting circuit 223 includes: a low-pass filtering converter and a first analog-to-digital converter.

[0076] A low-pass filter converter is used to filter out noise in the Coriolis shift signal.

[0077] The first analog-to-digital converter is used to convert the Coriolis shift signal into a digital signal, and the digital signal is used to calculate the angular velocity of the gyroscope.

[0078] See Figure 2 The detailed working process of the detection circuit 220 provided in the embodiment of the present disclosure is as follows:

[0079] The first C / V conversion circuit 221 converts the differential detection signal of the gyroscope (containing information such as orthogonal error, Coriolis shift and noise) into a voltage, performs differential operation and phase adjustment to convert it into a single-ended signal, and then amplifies it to an appropriate voltage value and outputs it as the first signal; the digitally controlled phase shifter 211 lags the phase of the first signal according to the input digital control amount, and provides the phase-shifted first signal to the phase-locked loop 212 and the coherent demodulator 222; the phase-locked loop 212 locks and filters the first signal, and outputs a second signal that is in phase with the first signal to the phase detector 213; the phase detector 213 compares the phase of the second signal (i.e., the orthogonal error) with the carrier, and converts the phase difference information into a voltage signal, which is then supplied to the charge pump 2141; The charge pump 2141 converts the voltage signal into an error current and supplies it to the loop filter 2142; the loop filter 2142 converts the error current into an error voltage; the error voltage is converted into a digital control quantity by the analog-to-digital converter 2143 and output to the adder 215 for addition with a preset digital quantity to control the digitally controlled phase shifter 211 so that the orthogonal error and the carrier achieve a precise 90-degree phase alignment; the coherent demodulator 222 coherently demodulates the first phase-shifted signal with the carrier to obtain a Coriolis shift signal, which is output to a low-pass filter; the low-pass filter filters out the high-frequency component of the Coriolis shift signal, leaving the DC component, which is supplied to the first analog-to-digital converter; the first analog-to-digital converter quantizes and encodes the DC component, converting it into a digital signal for use by subsequent systems.

[0080] See Figure 2In the embodiment of the present disclosure, the driving circuit 230 includes: a second C / V conversion circuit 231, a phase-locked loop 233, an amplitude detector 232, a comparator (not shown in the figure), and a variable gain amplifier 234.

[0081] The second C / V conversion circuit 231 is used to convert the capacitance change of the gyroscope into an electrical signal.

[0082] The phase-locked loop 233 is used to phase-lock and filter the electrical signal to obtain a carrier circuit, where the carrier signal is in phase with the electrical signal.

[0083] The amplitude detector 232 is used to detect the amplitude of the electrical signal.

[0084] A comparator, configured to compare the amplitude with a preset amplitude and output error information to thereby control the gain adjustment amount of the variable gain amplifier;

[0085] The variable gain amplifier 234 is used to amplify the output voltage of the phase-locked loop according to the adjustment amount to form an excitation voltage to drive the gyro device to form a stable working state.

[0086] See Figure 2 In this embodiment, the second C / V conversion circuit 231 converts the gyroscope's capacitance change into a voltage signal, performs phase adjustment and amplitude amplification accordingly, and transmits the signal to the amplitude detector 232 and phase-locked loop 233, respectively. The amplitude detector 232 obtains the voltage amplitude information and compares it with the preset amplitude in the comparator to obtain the voltage signal adjustment amount, which is used to adjust the gain of the variable gain amplifier 234. The phase-locked loop 233 captures and locks the voltage signal, filters it, and obtains a carrier signal. The carrier signal is in phase with the electrical signal. The carrier signal is transmitted to the coherent demodulator 222 in the detection circuit 220 and the variable gain amplifier 234 in the drive circuit 230, respectively. The drive circuit 230 not only excites the gyroscope's driving mode to form a stable frequency and amplitude oscillation, providing a basic guarantee for the normal operation of the detection circuit, but also provides the detection circuit 220 with a reference signal for correcting the phase of the orthogonal error signal and a carrier signal for the coherent demodulator.

[0087] In the embodiment of the present disclosure, the amplitude detector and the variable gain amplifier 234 form a driving displacement constant amplitude control circuit, so that the amplitude of the driving displacement remains constant; the phase-locked loop 233 used in the driving circuit 230 of the measurement and control scheme is connected to the Figure 1 The phase-locked loop in the technical solution provided is different. Figure 1 In the technical solution, the phase of the output of the phase-locked loop is 90 degrees ahead of the input. When the phase-locked loop 233 is locked, the output and input phases are strictly in phase, which greatly reduces the complexity of the drive circuit and also reduces the electrical noise of the drive circuit. In addition, compared with Figure 1The circuit provided, the driving circuit 230 provided in the embodiment of the present disclosure does not require the use of a phase shifter or a filter.

[0088] Optionally, the first C / V conversion circuit 221 and the second C / V conversion circuit 231 used in the embodiment of the present disclosure may be other converters or conversion circuits such as a transimpedance amplifier circuit.

[0089] A gyroscope measurement and control circuit provided by the present disclosure has the following beneficial effects: first, the stable amplitude mechanism of the driving circuit 230 ensures the constancy of the driving displacement, which is conducive to the stability of the Coriolis signal of the detection circuit 220; second, the circuit complexity and electrical noise of the driving circuit 230 are very low, and the reliability is high; third, the detection circuit 220 uses a phase-locked loop 212 and reasonably sets the input signal threshold, so that the phase jitter of the orthogonal error is lower, the accuracy of the phase alignment is improved, and the performance of coherent demodulation is improved; fourth, the detection circuit 220 uses a high-precision adaptive phase alignment circuit 210, which avoids the error introduced by manual relative alignment and avoids error creep affected by factors such as temperature, thereby improving the coherent demodulation performance.

[0090] It should be noted that the use of ordinal numbers such as "first," "second," and "third" in the specification and claims to modify corresponding elements does not in itself imply any ordinal number for the element, nor does it represent the order of one element relative to another, or the order in the manufacturing process. The use of such ordinal numbers is merely to clearly distinguish one element with a certain name from another element with the same name. Furthermore, the word "comprising" or "including" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

[0091] The present disclosure can be implemented by means of hardware including several different elements and by means of a suitably programmed computer. The various component embodiments of the present disclosure can be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. It should be understood by those skilled in the art that a microprocessor or digital signal processor (DSP) can be used in practice to implement some or all of the functions of some or all of the components in the related equipment according to the embodiments of the present disclosure. The present disclosure can also be implemented as a device or apparatus program (e.g., computer program and computer program product) for executing a part or all of the methods described herein. Such a program implementing the present disclosure can be stored on a computer-readable medium, or can have the form of one or more signals. Such a signal can be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

[0092] Those skilled in the art will appreciate that the features described in the various embodiments and / or claims of this disclosure may be combined and / or coupled in various ways, even if such combinations and / or couplings are not explicitly described in this disclosure. In particular, the features described in the various embodiments and / or claims of this disclosure may be combined and / or coupled in various ways without departing from the spirit and teachings of this disclosure. All such combinations and / or couplings are intended to fall within the scope of this disclosure.

[0093] Although the present disclosure has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made to the present disclosure without departing from the spirit and scope of the present disclosure as defined by the appended claims and their equivalents. Therefore, the scope of the present disclosure should not be limited to the above-described embodiments, but should be determined not only by the appended claims but also by the equivalents of the appended claims.

Claims

1. Adaptive phase alignment circuit, characterized in that, include: a digitally controlled phase shifter, configured to adjust the phase of the first signal; a phase-locked loop, configured to perform phase-locked filtering on the phase-shifted first signal to obtain a second signal from the first signal; a phase detector, configured to compare the phases of the second signal and the third signal to obtain a phase difference between the second signal and the third signal, wherein the second signal and the third signal are in a 90-degree phase alignment relationship; A signal conversion module, configured to convert the phase difference into a digital value; an adder, configured to calculate the sum of the digital quantity and a preset digital quantity to obtain a phase adjustment control quantity of the first signal, and transmit the phase adjustment control quantity to the digitally controlled phase shifter so that the digitally controlled phase shifter adjusts the phase of the first signal to be 90 degrees aligned with the third signal.

2. The circuit according to claim 1, further characterized in that: The digitally controlled phase shifter includes: an operational amplifier, a first resistor, a second resistor, and a digitally controlled pole adjustment sub-circuit; One end of the first resistor is connected to the input end of the first signal, and the other end is connected to the negative input end of the operational amplifier; one end of the second resistor is connected to the negative input end of the operational amplifier, and the other end is connected to the output end of the operational amplifier; the first port of the digital control pole adjustment sub-circuit is connected to the input end of the first signal, the second port is connected to the positive input end of the operational amplifier, and the third port is connected to the external digital signal input end.

3. The circuit according to claim 2, further characterized in that: The digitally controlled pole adjustment subcircuit includes at least a digitally controlled adjustable resistor or a digitally controlled adjustable capacitor, which is controlled by the external digital signal and is used to adjust the pole position of the digitally controlled phase shifter so that the phase of the first signal changes accordingly.

4. The circuit according to claim 1, wherein: The signal conversion module includes: a charge pump, configured to convert the phase difference into a current signal; a loop filter, configured to convert the current signal into a voltage signal; The analog-to-digital converter is used to convert the voltage signal into the digital value.

5. The circuit according to claim 1, wherein: The phase-locked loop is provided with an input signal threshold, and only a portion of the first signal that is higher than the input signal threshold is input into the phase-locked loop.

6. The circuit according to claim 5, characterized in that After the phase-locked loop performs phase-locked filtering on the first signal, the output second signal is in phase with the first signal.

7. A method for debugging an adaptive phase alignment circuit, applied to the adaptive phase alignment circuit according to any one of claims 1 to 6, characterized in that: include: S1, disconnect the connection line between the loop filter and the analog-to-digital converter; S2, fixing the voltage of the analog-to-digital converter to Vref / 2, where Vref is the input voltage range of the analog-to-digital converter; S3, inputting a first signal to the digitally controlled phase shifter; S4, adjusting the preset digital quantity so that the second signal output by the phase-locked loop and the third signal are aligned in phase by 90 degrees; S5, fixing the preset digital value; S6, connect the loop filter and analog-to-digital converter to complete the debugging.

8. A gyroscope measurement and control circuit, comprising the adaptive phase alignment circuit according to any one of claims 1 to 6, characterized in that: include: A driving circuit, used for driving the gyroscope to operate and obtaining a carrier signal of a coherent demodulator of the gyroscope; The detection circuit includes the adaptive phase alignment circuit, which is used to align the quadrature error signal generated during the operation of the gyroscope with the carrier signal at 90 degrees to obtain the Coriolis shift signal of the gyroscope.

9. The circuit according to claim 8, further characterized in that: The detection circuit comprises: a first C / V conversion circuit, configured to convert a differential detection signal generated during operation of the gyroscope into a first signal, wherein the first signal at least includes the quadrature error signal and the Coriolis shift signal; an adaptive phase alignment circuit, configured to adjust the phase of the quadrature error signal so that the phase of the quadrature error signal is aligned 90 degrees with the carrier signal; a coherent demodulator, configured to coherently demodulate the first signal after the phase shift of the quadrature error signal and the carrier signal to obtain the Coriolis shift signal; The filter conversion circuit is used to filter the Coriolis shift signal and convert it into a required signal type.

10. The circuit according to claim 9, characterized in that The filtering conversion circuit includes: a low-pass filter converter, configured to filter out noise in the Coriolis shift signal; The first analog-to-digital converter is used to convert the Coriolis shift signal into a digital signal, and the digital signal is used to calculate the angular velocity of the gyroscope.

11. The circuit according to claim 8, characterized in that The driving circuit includes: a second C / V conversion circuit, configured to convert a capacitance change of the gyroscope into an electrical signal; a phase-locked loop, configured to phase-lock and filter the electrical signal to obtain the carrier signal, wherein the carrier signal is in phase with the electrical signal; an amplitude detector, configured to detect the amplitude of the electrical signal; a comparator, configured to compare the amplitude with a preset amplitude to obtain a gain adjustment amount of the variable gain amplifier; A variable gain amplifier is used to amplify the carrier signal according to the adjustment amount and output it to the gyroscope.

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