CN217585825U

CN217585825U - Open-loop readout circuit structure of gyroscope

Info

Publication number: CN217585825U
Application number: CN202221317349.4U
Authority: CN
Inventors: 山永启; 熊坤; 张潭; 徐浩谋; 陈方
Original assignee: Sichuan Weizhu Technology Co ltd
Current assignee: Sichuan Weizhu Technology Co ltd
Priority date: 2022-05-30
Filing date: 2022-05-30
Publication date: 2022-10-14
Anticipated expiration: 2032-05-30

Abstract

The utility model discloses a gyroscope open loop reading circuit structure, which comprises a driving loop, an orthogonal compensation and detection path, a digital processing system and a power management module; the MEMS gyroscope sensitive structure is electrically connected with a driving loop, and the driving loop is respectively electrically connected with the orthogonal compensation and detection path and the digital processing system; the MEMS gyroscope sensitive structure is electrically connected with the orthogonal compensation and detection channel, and the orthogonal compensation and detection channel is respectively electrically connected with the driving channel and the digital processing system; a power management module configured to power the drive loop, the quadrature compensation and detection path, and the digital processing system. The utility model discloses can configure the register and match different sensitive structures of gyroscope, improve the adaptation scope of reading out the circuit.

Description

Open-loop readout circuit structure of gyroscope

Technical Field

The utility model belongs to the technical field of micromechanical gyroscope, concretely relates to gyroscope open-loop reads circuit structure.

Background

The operating mechanism of a micro-mechanical (MEMS) gyroscope is based on the Goldcell force effect, a driving electrostatic force is applied to a gyroscope driving mode, so that a mass block is subjected to constant amplitude vibration in a driving direction, when an external angular velocity is input, the mass block is caused to move in a detection direction, and a reading circuit picks up the movement amount in the detection direction, so that the angular velocity measurement is realized. A typical gyro sensitive structure is shown in fig. 2, at present, most of the gyro sensitive structures in various units and institutions are still in a development stage, and in order to adapt to different gyro sensitive structures, a reading circuit needs to be customized according to corresponding structure parameters. Meanwhile, process deviation can be introduced into a sensitive structure of the gyroscope during processing, for example, zero deviation is introduced into capacitance value deviation of upper and lower differential capacitors during detection and driving, for example, incomplete verticality and rigidity asymmetry during detection and driving, and orthogonal signals are introduced into damping coupling.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to the above-mentioned among the prior art not enough, provide a gyroscope open loop and read out circuit structure to solve the current micromechanical gyroscope and read out the poor problem of circuit suitability.

In order to achieve the purpose, the utility model adopts the technical proposal that:

a gyroscope open loop reading circuit structure comprises a driving loop, an orthogonal compensation and detection path and a digital processing system;

the driving loop is respectively connected with the MEMS gyroscope sensitive structure, the orthogonal compensation and detection channel and the digital processing system; the MEMS gyroscope sensitive structure is connected with the orthogonal compensation and detection channel; the orthogonal compensation and detection path is connected with the digital processing system;

the driving loop comprises a driving capacitor voltage conversion circuit DC2V, a driving loop high-voltage control circuit DHVD and a phase-locked loop frequency multiplication circuit PLL; and the driving capacitor voltage conversion circuit DC2V, the driving loop high-voltage control circuit DHVD and the phase-locked loop frequency multiplication circuit PLL are all connected with the MEMS gyroscope sensitive structure.

Furthermore, the driving loop also comprises a driving band-pass filter circuit DPGA; the output of the driving band-pass filter circuit DPGA is respectively connected with the input of the driving loop amplitude control circuit DCTL and the input of the comparator circuit CMP; and a DC2V signal output end 7 of the driving capacitor voltage conversion circuit is connected with the input of the driving band-pass filter circuit DPGA and the adder ADD, and a DC2V self-calibration output end 9 is connected with the digital processing module DPM.

Further, the driving loop further comprises a driving loop amplitude control circuit DCTL, a voltage control gain circuit DVGA and a comparator circuit CMP;

the output of the driving loop amplitude control circuit DCTL is connected with the input of the voltage control gain circuit DVGA; the output of the voltage control gain circuit DVGA meets the input of the DHVD circuit of the high-voltage control of the driving loop; the output of the comparator circuit CMP is connected to the input of the phase locked loop frequency multiplier circuit PLL.

Further, the output of the phase-locked loop frequency multiplication circuit PLL comprises an in-phase demodulation signal CK00 and a 90-degree phase difference demodulation signal CKN90; the demodulation signal CK00 and the demodulation signal CKN90 are connected with the input of the angular speed and orthogonal signal demodulation DEM circuit;

the in-phase demodulation signal CK00 is also connected with the input of a quadrature compensation integral control circuit QPIC;

and a mass block carrier signal STR generated by a phase-locked loop frequency multiplication circuit PLL is connected with a mass block end 5 of the MEMS gyroscope sensitive structure.

Further, the quadrature compensation and detection path includes: detecting a capacitance voltage conversion circuit SC2V and an orthogonal compensation high-voltage control circuit QHVD;

the detection end 3 of the MEMS gyroscope sensitive structure is connected with the voltage input end of the detection capacitor voltage conversion circuit SC 2V; the self-calibration output end 10 of the SC2V is connected with a digital processing module DPM;

and the quadrature compensation high-voltage control circuit QHVD is connected with the quadrature stiffness compensation end 1 of the MEMS gyroscope sensitive structure.

Further, the quadrature compensation and detection path further comprises: the device comprises an adder ADD, a detection band-pass filter circuit SPGA, an orthogonal compensation integral control circuit QPIC and an angular velocity and orthogonal signal demodulation circuit DEM;

a signal output end 7 of the driving capacitor voltage conversion circuit DC2V and a signal output end 8 of the detection capacitor voltage conversion circuit SC2V are both connected with an input end of the adder ADD; the addition result output end of the adder ADD is connected with the input of the detection band-pass filter circuit SPGA;

the output of the detection band-pass filter circuit SPGA is connected with the input of the quadrature compensation integral control circuit QPIC and the input of the angular velocity and quadrature signal demodulation circuit DEM;

the output of the quadrature compensation integral control circuit QPIC is connected to the input of the quadrature compensation high voltage control circuit QHVD and the input of the adder ADD.

Further, the quadrature compensation and detection path further comprises: a low-pass filter circuit SLPF and an angular velocity and quadrature signal quantization circuit SADC;

the output end of the angular velocity and orthogonal signal demodulation circuit DEM is connected with the input end of the low-pass filter circuit SLPF;

the output end of the low-pass filtering SLPF circuit is connected with the input end of the angular velocity and quadrature signal quantization circuit SADC.

Further, the digital processing system comprises a temperature sensor quantification (TADC), a nonvolatile memory (NVP) and a Digital Processing Module (DPM);

the digital processing module DPM is connected with a self-calibration output end 9 of the driving capacitor voltage conversion circuit DC2V and a self-calibration output end 10 of the detection capacitor voltage conversion circuit SC 2V;

a voltage signal output by the temperature sensor VTSEN is quantized by a temperature sensor quantization circuit TADC and then is accessed to a digital processing module DPM for temperature compensation;

the DPM system built-in filter bank configures system output bandwidth through a nonvolatile memory NVP.

The utility model provides a gyroscope open loop reads out circuit structure has following beneficial effect:

the utility model discloses can configure the register and match different sensitive structures of gyroscope, improve the adaptation scope of reading out circuit.

Drawings

Fig. 1 is a schematic diagram of an embodiment of a gyroscope open-loop readout circuit structure.

Fig. 2 is a schematic diagram of an internal structure of a conventional MEMS gyroscope.

Fig. 3 is a schematic diagram of an embodiment of a capacitor voltage converting circuit.

Fig. 4 is a schematic diagram of an embodiment of an angular velocity and quadrature signal demodulation circuit.

Wherein, the reference numbers in fig. 2 are:

1-driving comb teeth; 2-drive detection; 3, detecting comb teeth; 4-an elastic beam; 5-driving the support beam; 6-detecting the support beam; 7-a mass block; 8-anchor point.

The circuit corresponding to the letter in fig. 2 is:

DC 2V-drive capacitance voltage conversion circuit, DGPA-drive band-pass filter circuit, DCTL-drive loop amplitude control circuit, DVGA-voltage control gain circuit, DHVD-drive loop high-voltage control circuit, CMP-comparator circuit, PLL-phase-locked loop frequency multiplier circuit, SC 2V-detection capacitance voltage conversion circuit, ADD-adder, SPGA-detection band-pass filter circuit, DEM-angular velocity and quadrature signal demodulation circuit, SLPF-low-pass filter circuit, SADC-angular velocity and quadrature signal quantization circuit, QPIC-quadrature compensation integral control circuit, QHVD-quadrature compensation high-voltage control circuit, VTSEN-temperature sensor, TADC-temperature sensor quantization, NVP-nonvolatile memory, DPM-digital processing module, REF-reference voltage and bias current generation circuit, POR-power-on reset circuit, LDO-digital power supply voltage and analog reference voltage generation circuit, CPP-charge pump generation circuit.

In the circuit of fig. 3: 1-differential operational amplifier, 2-analog multiplier, 3-comparator;

in the circuit of fig. 4: 1-differential operational amplifier, 2-alternative selector, 3-inverter, 4-buffer.

Detailed Description

The following description of the embodiments of the present invention is provided to facilitate the understanding of the present invention by those skilled in the art, but it should be understood that the present invention is not limited to the scope of the embodiments, and various changes may be made apparent to those skilled in the art within the spirit and scope of the present invention as defined and defined by the appended claims.

According to an embodiment of the present application, referring to fig. 2, the gyroscope open-loop readout circuit structure of the present solution includes a driving loop, a quadrature compensation and detection path, a digital processing system, and a power management module.

A drive loop configured to start the drive displacement in the drive shaft direction and stabilize the vibration amplitude at a set value; specifically, the MEMS gyroscope sensitive structure is electrically connected with a driving loop, and the driving loop is respectively electrically connected with the orthogonal compensation and detection path and the digital processing system.

An orthogonal compensation and detection path configured to orthogonally compensate the MEMS gyroscope sensitive structure;

specifically, the MEMS gyroscope sensitive structure is electrically connected with an orthogonal compensation and detection channel, and the orthogonal compensation and detection channel is respectively electrically connected with a driving channel and a digital processing system.

The power management module is configured to supply power to the driving loop, the quadrature compensation and detection path, and the digital processing system, and the power management module may be implemented by using the prior art, which is not limited herein.

The further technical scheme of the driving loop of the embodiment is as follows:

the driving loop comprises a driving capacitor voltage conversion circuit DC2V, a driving band-pass filter circuit DPGA, a driving loop amplitude control circuit DCTL, a voltage control gain circuit DVGA, a driving loop high-voltage control circuit DHVD, a comparator circuit CMP and a phase-locked loop frequency doubling circuit PLL.

The specific connection relationship of the circuit is as follows:

the drive detection end 2 of the MEMS gyroscope sensitive structure is connected with the voltage input end of a drive capacitor voltage conversion circuit DC 2V; the driving end 4 of the MEMS gyroscope sensitive structure is connected with the output of the driving loop high-voltage control circuit DHVD; and the mass block end of the MEMS gyroscope is connected with a mass block carrier signal STR output by a PLL frequency doubling circuit PLL.

In a driving loop, a driving capacitor voltage conversion circuit DC2V processes a signal at a driving detection end of a gyroscope sensitive structure, a driving capacitor voltage conversion circuit DC2V signal output end 7 is connected with the input of a driving band-pass filter circuit DPGA and an adder ADD, and a DC2V self-calibration output end 9 is connected with a digital processing module DPM; the output of the driving band-pass filter circuit DPGA is connected with the input of the driving loop amplitude control circuit DCTL, and is simultaneously connected with the input of the comparator circuit CMP; the output of the driving loop amplitude control circuit DCTL is connected with the input of the voltage control gain circuit DVGA; the output of the voltage control gain circuit DVGA is connected with the input of the drive loop high-voltage control DHVD circuit; the output of the comparator circuit CMP is connected to the input of the phase-locked loop frequency multiplier circuit PLL.

The working principle of the driving loop of the embodiment is as follows:

the PLL frequency multiplier circuit PLL performs frequency locking according to the output signal of the comparator, the output comprises an in-phase demodulation signal CK00 and a 90-degree phase difference demodulation signal CKN90, the two demodulation signals are connected with the input of an angular velocity and orthogonal signal demodulation DEM circuit and used for angular velocity and orthogonal signal demodulation, and the in-phase demodulation signal CK00 is further connected with the input of an orthogonal compensation integral control circuit QPIC and used for rigidity compensation orthogonal demodulation. The generated mass block carrier signal STR is connected to a mass block end 5 of the MEMS gyroscope sensitive structure and is used for providing a carrier signal for the mass block of the sensitive structure, a phase-locked loop frequency multiplier circuit PLL generates a carrier signal VTR signal with a phase opposite to that of the STR and is connected with a matching capacitor of a driving capacitor voltage conversion circuit DC2V and a detection capacitor voltage conversion circuit SC2V, the matching capacitor and the capacitance of the gyroscope sensitive structure form a full-bridge structure, the capacitance of the gyroscope sensitive structure causes the jump of an input common mode point to be offset by the jump of the matching capacitor in the opposite direction, the voltages of upper detection electrodes and lower detection electrodes of the two capacitance voltage conversion circuits are kept stable, and the VTR signal is simultaneously connected to a zero-bias compensation capacitor and is used for compensating the mismatch of the capacitance of the gyroscope sensitive structure.

The driving capacitance-voltage conversion circuit has the function of converting capacitance change on the driving detection end 2 of the MEMS gyroscope sensitive structure into differential voltage for output; the function of the driving band-pass filter circuit DPGA is to filter out clutter signals outside the frequency band of interest.

The driving loop amplitude control circuit DCTL limits the amplitude of the output signal of the driving band-pass filter circuit DPGA within a set value; the voltage control gain circuit DVGA is used for providing variable gain in a driving oscillation starting stage and has the function of adjusting the gain according to the oscillation amplitude of an input signal, the gain is larger when the oscillation amplitude is smaller, the gain is gradually reduced when the oscillation amplitude is gradually increased, and the gain is kept unchanged when the oscillation amplitude reaches a set value.

The driving loop high-voltage control circuit DHVD converts the output low-voltage signal of the voltage control gain circuit DVGA into a high-voltage signal, and the driving loop provides adjustable gain amplification and high-voltage preloading to generate electrostatic force for starting vibration of the gyroscope sensitive structure.

The driving loop is used for enabling the driving displacement to start vibration in the direction of the driving shaft and enabling the vibration amplitude to be stabilized at a set value. The comparator circuit CMP and the phase-locked loop frequency multiplication circuit PLL finish picking up and locking the driving resonance frequency of the sensitive structure of the gyroscope, CK00 with the same phase as the driving resonance frequency is output by the phase-locked loop frequency multiplication circuit PLL and used for quadrature demodulation, CKN90 with the driving resonance frequency of 90 DEG is used for angular velocity demodulation, a mass block carrier signal STR, a driving capacitor voltage conversion circuit DC2V, a matching capacitor carrier signal VTR of a detection capacitor voltage conversion circuit SC2V are generated, and working frequency signals of an angular velocity and quadrature signal quantization circuit SADC, a temperature sensor quantization module TADC and a digital processing module DPM are generated.

The circuit functions and specific circuit implementation modes of the band-pass filter circuit DGPA, the driving loop amplitude control circuit DCTL, the voltage control gain circuit DVGA and the driving loop high-voltage control circuit DHVD belong to the prior art in the field, and are not described herein again.

The further technical scheme of the orthogonal compensation and detection path of the embodiment is as follows:

the orthogonal compensation and detection path comprises a detection capacitance-voltage conversion circuit SC2V, an adder ADD, a detection band-pass filter circuit SGPA, an orthogonal compensation integral control circuit QPIC, an orthogonal compensation high-voltage control circuit QHVD, an angular velocity and orthogonal signal demodulation circuit DEM, a low-pass filter circuit SLPF and an angular velocity and orthogonal signal quantization circuit SADC.

The connection relationship of each circuit structure in the quadrature compensation and detection path in this embodiment is:

the detection end 3 of the MEMS gyroscope sensitive structure is connected with the voltage input end of the detection capacitor voltage conversion circuit SC 2V; and the orthogonal rigidity compensation end 1 of the MEMS gyroscope sensitive structure is connected with the output end of the orthogonal compensation high-voltage control circuit QHVD.

A signal output end 7 of the driving capacitor voltage conversion circuit DC2V and a signal output end 8 of the detection capacitor voltage conversion circuit SC2V are connected with an input end of the adder ADD; the self-calibration output end 10 of the SC2V is connected with a digital processing module DPM; the output end of the addition result of the adder ADD is connected with the input end of the detection band-pass filter circuit SPGA; the detection band-pass filter circuit SPGA outputs and is connected with the input of a quadrature compensation integral control circuit QPIC, and simultaneously connected with the input of an angular velocity and quadrature signal demodulation circuit DEM; the output of the quadrature compensation integral control circuit QPIC is connected to the input of the quadrature compensation high voltage control circuit QHVD and the input of the adder ADD.

The output end of the angular velocity and orthogonal signal demodulation circuit DEM is connected with the input end of the low-pass filter circuit SLPF; the output end of the low-pass filtering SLPF circuit is connected with the input end of the angular velocity and orthogonal signal quantization circuit SADC, and meanwhile, the output end of the low-pass filtering SLPF circuit is also used as the output of the analog angular velocity and orthogonal signal, and the use is convenient for users.

The working principle of each circuit structure in the quadrature compensation and detection path in this embodiment is as follows:

the detection capacitance-voltage conversion circuit SC2V has the function of converting capacitance change on the detection end 2 of the MEMS gyroscope sensitive structure into differential voltage for output.

One embodiment of the driving and detecting capacitor-voltage converting circuit is shown in fig. 3, where Cm is a base capacitor of a gyroscope sensing structure, C0 is a matching capacitor corresponding to Cm, and Cc is a zero-offset compensation capacitor. Cm, cb and Cc form a capacitance bridge; the input of the differential operational amplifier is used as the input end of the capacitor voltage conversion circuit, cf is an amplification feedback capacitor, the output of the differential operational amplifier is connected with the input of the comparator, and the output of the comparator is connected with the digital processing module DPM, so that self calibration of the matching capacitor and the zero-offset compensation capacitor is realized.

The adder ADD ADDs output signals of the driving capacitance-voltage conversion circuit DC2V, the detection capacitance-voltage conversion circuit SC2V, and the quadrature compensation integration control circuit QPIC, outputs the result to the detection band-pass filter circuit SPGA, and outputs the result to the angular velocity and quadrature demodulation circuit DEM and the quadrature compensation integration control circuit QPIC after band-pass filtering.

The quadrature compensation integral control circuit QPIC picks up a quadrature amplitude value and sends the quadrature amplitude value to the quadrature compensation high-voltage control circuit QHVD and the adder ADD for quadrature compensation, the quadrature compensation high-voltage control circuit QHVD has the functions that a compensation signal is generated through an integral signal output by the quadrature compensation integral control circuit QPIC and output to a rigidity compensation end of a sensitive structure of the MEMS gyroscope, and the electrostatic force is adjusted through configuring the gain of the quadrature compensation high-voltage control circuit QHVD to offset the orthogonal force of rigidity coupling, so that the rigidity compensation of the quadrature signal is realized.

The angular velocity and orthogonal signal demodulation circuit DEM is used for receiving an in-phase demodulation signal CK00 for orthogonal demodulation, receiving a 90-degree phase difference demodulation signal CKN90 for angular velocity demodulation, filtering the demodulated signal through a low-pass filter circuit SLPF, inputting the filtered signal to an angular velocity and orthogonal signal quantization circuit SADC, converting the demodulated signal into a digital signal bitstrim by the angular velocity and orthogonal signal quantization circuit SADC, and inputting the digital signal bitstrim to a digital processing module DPM to complete a subsequent digital function algorithm.

The specific circuit implementation of the angular velocity and quadrature signal demodulation circuit DEM and the quadrature compensation integral control circuit QPIC is the prior art in the field.

For example, as shown in fig. 4, a typical implementation of the circuit of the angular velocity and quadrature signal demodulation circuit DEM is that an input signal is differentially amplified by a differential operational amplifier 1 and then output, an in-phase demodulation signal CK00 and a 90-degree phase difference demodulation signal CKN90 are used as control signals to control quadrature demodulation or angular velocity demodulation, and a feedback resistor Rf in fig. 4 implements a feedback function.

When the QEMOM input signal of the demodulation mode pin is high level, the alternative selector 2 selects the in-phase demodulation signal CK00, and the angular velocity and orthogonal signal demodulation circuit DEM receives the in-phase demodulation signal CK00 for orthogonal demodulation; when the demodulation mode pin QEMOD is low level, the alternative selector 2 selects the 90-degree phase difference demodulation signal CKN90, the angular velocity and quadrature signal demodulation circuit DEM receives the 90-degree phase difference demodulation signal CKN90 for angular velocity demodulation, CKP and CKN in fig. 4 are internal control signals that are mutually inverted, and the output signal of the selector passes through an in-phase buffer stage and an inverted buffer stage formed by a buffer 4 and an inverter 3, respectively.

The orthogonal error may be caused by displacement coupling or rigidity coupling, the displacement coupling can be equivalently regarded as the projection of the driving displacement to the detection displacement, the orthogonal signal caused by the coupling still has a 90-degree phase shift with the driving displacement after passing through a detection capacitance-voltage conversion circuit SC2V, the rigidity coupling is mainly caused by the coupling rigidity of a driving axial detection shaft, the rigidity coupling generates a phase shift after passing through a detection resonant cavity, and still has a 90-degree phase shift with the Coriolis force and has a 90-degree plus phase shift with the driving displacement after detecting CV.

When the quadrature error is displacement coupling, the quadrature compensation adopts a charge injection method, firstly an RGBUS register is configured for the adder ADD through a digital processing module DPM to offset most of the quadrature error, and then the residual quadrature error is offset through quadrature compensation integral control circuit QPIC closed-loop control.

When the quadrature error is rigidity coupling, an RGBUS register is configured by a digital processing module DPM to adjust gain for a quadrature compensation high-voltage control circuit QHVD, so that electrostatic force counteracts the orthogonal force of the rigidity coupling; if the quadrature error of the sensitive structure of the gyroscope simultaneously contains displacement coupling and rigidity coupling, an RGBUS register is configured to simultaneously complete compensation of quadrature signals by a charge injection method and a rigidity compensation method.

After the orthogonal compensation is carried out by a charge injection method and a rigidity compensation method, the angular speed output temperature characteristic and the zero offset stability of the system can be greatly improved. The selection enabling and specific parameters of the two orthogonal compensation methods can be flexibly configured through the NVP and the DPM.

The digital processing module DPM can realize the self-calibration of the matching capacitor C0 and the zero offset compensation Cc by processing the self-calibration output signal of the driving loop capacitor voltage conversion circuit and the self-calibration output signal of the detection loop capacitor voltage conversion circuit.

The digital processing system of the embodiment further has the technical scheme that:

the digital processing system comprises a temperature sensor quantification TADC, a nonvolatile memory NVP and a digital processing module DPM.

The digital processing system of the embodiment combines a driving loop, an orthogonal compensation and detection path, a power management module and other circuits, and the working principle is as follows:

the digital processing module DPM receives self-calibration output signals CLBO _ D and CLBO _ S of a self-calibration output end 9 of a driving capacitor voltage conversion circuit DC2V and a self-calibration output end 10 of a detection capacitor voltage conversion circuit SC2V, a calibration comparator in the capacitor voltage conversion circuit compares the sizes of a gyroscope sensitive structure capacitor and a matching capacitor, picks up zero offset of the gyroscope sensitive structure capacitor, outputs the zero offset to the digital processing module DPM to calculate configuration register values needed by the matching capacitor and the zero offset compensation capacitor, and completes adjustment self-calibration of the matching capacitor and the zero offset compensation capacitor through REGBUS bus feedback; and the DPM receives the angular velocity and bitstrim output by the orthogonal signal quantization circuit SADC, and performs extraction filtering, temperature compensation, scale factor calibration, system bandwidth configuration and the like.

The reference current bias temperature sensor REF circuit generates low temperature drift and high-precision reference voltage to be supplied to the driving loop amplitude control circuit DCTL, and a voltage signal output by the temperature sensor VTSEN is quantized by the temperature sensor quantization circuit TADC and then is accessed to the digital processing module DPM for temperature compensation.

The charge pump generating circuit CPP is used to generate a higher output voltage as a high voltage power supply, driving the loop high voltage control circuit DHVD and the quadrature compensation high voltage control circuit QHVD. The power-on reset circuit POR is used for generating a power-on reset signal and enabling a circuit system after power-on.

The non-volatile memory NVP and the digital processing module DPM generate RGBUS (REGISTER BUS) REGISTERs for storing parameters, and the REGISTERs are connected with the driving loop amplitude control circuit DCTL, the charge pump generating circuit CPP, the driving loop high-voltage control circuit DHVD, the orthogonal compensation high-voltage control circuit QHVD, the phase-locked loop frequency doubling circuit PLL and the like, so that flexible configuration of circuit parameters is realized.

The NVP and the DPM can carry out angular speed output zero offset temperature coefficient calibration, zero offset compensation and scale factor calibration; the digital processing module DPM system built-in filter bank can also configure the system output bandwidth through a nonvolatile memory NVP; the digital processing module DPM can have built-in digital communication interfaces such as I2C, PSI, RS _458, etc., and can be selected by the non-volatile memory NVP configuration. According to the parameters of the gyroscope sensitive structures of different users, the nonvolatile memory NVP and the digital processing module DPM are used for configuring the matching capacitor to match the gyroscope sensitive structures, and the adaptation range of the reading circuit to the gyroscope sensitive structures is widened.

The driving loop amplitude control circuit DCTL can be configured through a nonvolatile memory NVP and a digital processing module DPM, so that the parameter requirements of different user sensitive structures are met, and the adaptation range of the readout circuit to the gyroscope sensitive structure is widened.

The output of the angular speed signal analog quantity or digital quantity can be selected through the NVP and the DPM, so that the use by a user is facilitated. When the analog quantity is output, digital parts such as an ADC (analog to digital converter) can be closed through the register, so that the power consumption of the whole device is reduced.

Output voltage of the charge pump generating circuit CPP is flexibly configured through the NVP of the nonvolatile memory and the DPM, gains of the DHVD and the QHVD are driven, and the adaptation range of the readout circuit to a gyroscope sensitive structure is expanded.

According to the resonant frequency of the gyroscope sensitive structure of different users, the locking frequency of the PLL frequency multiplier circuit PLL can be flexibly configured through the nonvolatile memory NVP and the digital processing module DPM, and the adaptation range of the readout circuit to the gyroscope sensitive structure is expanded.

The driving band-pass filter circuit DPGA, the detection band-pass filter circuit SPGA and the phase-locked loop frequency multiplier circuit PLL are internally provided with a phase compensation circuit, and the relative phase shift of a driving signal and a detection signal is configured by combining a nonvolatile memory NVP and a digital processing module DPM, so that the accuracy of quadrature compensation and angular speed demodulation phase is improved.

A communication interface is selected through a nonvolatile memory NVP and a digital processing module DPM, and the communication interface is compatible with SPI, I2C, RS _458 and the like, so that a user can conveniently use the communication interface according to the interface of the user; the non-volatile memory NVP comprises a one-time programmable memory OTP and a multi-time erasable memory MTP.

The utility model discloses a readout circuit suitability is stronger, can match different users' sensitive structure of gyroscope, eliminates the orthogonal signal and guarantees the performance and the yield of device.

While the present invention has been described in detail with reference to the embodiments, the scope of the present invention should not be limited to the embodiments. Various modifications and changes may be made by those skilled in the art without inventive step within the scope of the appended claims.

Claims

1. A gyroscope open loop readout circuit structure is characterized in that: the system comprises a driving loop, an orthogonal compensation and detection path and a digital processing system;

the driving loop is respectively connected with the MEMS gyroscope sensitive structure, the orthogonal compensation and detection channel and the digital processing system; the MEMS gyroscope sensitive structure is connected with the orthogonal compensation and detection channel; the orthogonal compensation and detection path is connected with a digital processing system;

2. The gyroscope open loop readout circuit structure of claim 1, wherein the drive loop further comprises a drive bandpass filter circuit DPGA; the output of the driving band-pass filter circuit DPGA is respectively connected with the input of the driving loop amplitude control circuit DCTL and the input of the comparator circuit CMP; and a DC2V signal output end 7 of the driving capacitor voltage conversion circuit is connected with the input of the driving band-pass filter circuit DPGA and the adder ADD, and a DC2V self-calibration output end 9 is connected with the digital processing module DPM.

3. The gyroscope open loop readout circuit structure of claim 1, wherein the drive loop further comprises a drive loop magnitude control circuit DCTL, a voltage control gain circuit DVGA, and a comparator circuit CMP;

the output of the driving loop amplitude control circuit DCTL is connected with the input of the voltage control gain circuit DVGA; the output of the voltage control gain circuit DVGA meets the input of the drive loop high-voltage control DHVD circuit; the output of the comparator circuit CMP is connected to the input of the phase locked loop frequency multiplier circuit PLL.

4. The gyroscope open loop readout circuit structure of claim 3, wherein the phase locked loop frequency multiplier circuit PLL output comprises an in-phase demodulation signal CK00 and a 90 degree phase difference demodulation signal CKN90; the demodulation signal CK00 and the demodulation signal CKN90 are connected with the input of the angular speed and orthogonal signal demodulation DEM circuit;

the in-phase demodulation signal CK00 is further connected with the input of a quadrature compensation integral control circuit QPIC;

and a mass block carrier signal STR generated by the phase-locked loop frequency doubling circuit PLL is connected with a mass block end 5 of the MEMS gyroscope sensitive structure.

5. The gyroscope open loop readout circuit structure of claim 1, wherein the quadrature compensation and detection path comprises: detecting a capacitance voltage conversion circuit SC2V and an orthogonal compensation high-voltage control circuit QHVD;

6. The gyroscope open loop readout circuit structure of claim 5, wherein the quadrature compensation and detection path further comprises: the device comprises an adder ADD, a detection band-pass filter circuit SPGA, an orthogonal compensation integral control circuit QPIC and an angular velocity and orthogonal signal demodulation circuit DEM;

the output of the quadrature compensation integration control circuit QPIC is connected to the input of the quadrature compensation high voltage control circuit QHVD and the input of the adder ADD.

7. The gyroscope open loop readout circuit structure of claim 6, wherein the quadrature compensation and detection path further comprises: a low-pass filter circuit SLPF and an angular velocity and quadrature signal quantization circuit SADC;

8. The gyroscope open loop readout circuit structure of claim 7, wherein the digital processing system comprises a temperature sensor quantization TADC, a non-volatile memory NVP and a digital processing module DPM;

voltage signals output by the temperature sensor VTSEN are quantized by a temperature sensor quantization circuit TADC and then are accessed to a digital processing module DPM for temperature compensation;