Continuous monitoring of gyroscope sensor forced rebalancing loop electronics

Abstract

A gyroscope sensor circuit includes: a gyroscope sensor generating an RF sensing signal according to an angular motion; and an RF sensing path configured to receive and process the RF sensing signal. The RF sensing path includes: a first chopper configured to chop an RF signal at a first chopping frequency to generate a chopped signal; and a demodulator configured to mix the chopped signal with the LO signal to output a baseband signal. The circuit also includes a feedback loop including: a chopping remodulator configured to chop and modulate the baseband signal at a frequency of the LO signal; a first amplifier configured to amplify the modulated feedback signal; and a test voltage monitor configured to extract a component corresponding to the LO signal from the modulated feedback signal and compare a voltage of the extracted component with an expected value determined based on a gain of the first amplifier.

Description

Technical Field

[0001] The present disclosure relates to gyroscopic sensor circuits for continuously monitoring the functionality and accuracy of electronic components in a forced rebalance forward path and feedback path to ensure high performance of a closed-loop forced rebalance system. Background Art

[0002] Gyroscope sensors typically employ a forced rebalance (FTR) feedback loop to desensitize system gain and linearity to gyroscope gain, quality factor (Q), and linearity, and to extend the bandwidth of the system beyond that of an open-loop gyroscope.

[0003] Through the FTR feedback loop, the feedback electronics provide better control over end-to-end gain and linearity than an open-loop sensing architecture.

[0004] The sensitivity of a gyroscope is typically calibrated by the gyroscope vendor using a known rotational stimulus sequence. However, sensitivity depends on multiple electromechanical properties that are sensitive to strain and / or change over the lifetime of the gyroscope. As a result, the sensitivity shifts after the gyroscope is installed in the end user's system, or drifts over the lifetime of the gyroscope. Since the true input stimulus in the gyroscope cannot be observed after installation, it is difficult to conveniently recalibrate the sensitivity of the gyroscope when the gyroscope is deployed in the field.

[0005] While this FTR feedback method has the advantage of including a gyroscope in the system monitoring, inaccuracies or false alarms may occur if external rotation or other disturbances occur when the test signal is applied (if the disturbance is at or close to the frequency of the test signal). Therefore, a technique is needed for continuous monitoring without the effects of external mechanical or electrical disturbances on the gyroscope sensor. Summary of the invention

[0006] One object of the present disclosure is to provide a gyro sensor circuit for continuously monitoring the functionality and accuracy of electronic components in an FTR loop to ensure high performance of a closed-loop FTR system.

[0007] A gyroscope sensor circuit with continuous monitoring capability can avoid the following problem: the test signal is passed through the gyroscope, and if there is an external signal or undesirable interference with the same frequency as the test signal, the gyroscope may not operate correctly.

[0008] In one aspect, a gyro sensor circuit includes: a gyro sensor that generates an RF sensing signal according to an angular motion of the gyro sensor; a radio frequency (RF) sensing path configured to receive and process the RF sensing signal. The RF sensing path includes: a first high gain low noise RF amplifier; a first chopper that includes a chopping switch and is configured to chop the RF signal at a first chopping frequency to generate a chopping signal; and a demodulator that is coupled to a local oscillator (LO) that generates an LO signal, the demodulator being configured to mix the chopped RF signal with the LO signal to output a baseband signal. The circuit also includes a feedback loop configured to feed back a baseband signal to the gyro sensor, the feedback loop including: a connection path configured to connect an LO oscillator to the feedback loop for remodulating the baseband signal to an RF band; a second amplifier for amplifying the baseband signal; a combined chopper / remodulator configured to chop and modulate the baseband signal at the frequency of the LO signal to generate a modulated feedback signal; a third amplifier configured to amplify the modulated feedback signal to drive the gyro electrodes; and a test voltage monitor configured to extract a dc component from the modulated feedback signal and compare the voltage of the extracted component with an expected value determined based on the gain of the third amplifier.

[0009] The RF sensing path may further include: a fourth amplifier configured to amplify the baseband signal; a chopper configured to chop the amplified baseband signal at a chopping frequency; and an analog-to-digital converter (ADC) configured to sample the amplified baseband signal for digitization.

[0010] The first amplifier and the third amplifier may be transimpedance amplifiers.

[0011] The second amplifier and the fourth amplifier may be transconductance amplifiers.

[0012] In another aspect, a gyro sensor circuit includes a gyro sensor that generates an RF sensing signal according to an angular motion of the gyro sensor; and an RF sensing path configured to receive and process the RF sensing signal. The RF sensing path includes: a DC current generator configured to generate a test DC current; a first chopper configured to chop the DC current at a first chopping frequency and provide the chopped test current to the RF sensing path, wherein the chopped test current and the RF sensing signal are combined into a combined signal; a first amplifier configured to amplify the combined signal; a second chopper configured to chop the combined signal at a second chopping frequency to output a chopped combined signal; a demodulator including an RF section and an LO section, wherein a pair of resistors separates the two sections; a test voltage monitor configured to extract a component corresponding to the test DC current from the chopped combined signal across the pair of resistors and compare the voltage of the extracted component with an expected value determined based on a gain of the first amplifier, the LO section of the demodulator being configured to mix the offset combined signal and the LO signal to generate a demodulated signal, and the demodulator also including a baseband filter configured to receive the demodulated signal and pass a passband signal.

[0013] The first chopper and the second chopper may be configured to perform chopping operations at the same chopping frequency.

[0014] The gyro sensor circuit may further include a feedback loop configured to feed back the baseband signal to the gyro sensor, the feedback loop including a chopper-modulator combination configured to chop the baseband signal to output a modulated baseband signal.

[0015] The feedback loop may further include a third amplifier configured to amplify the modulated baseband signal.

[0016] The RF sensing path may further include a fourth amplifier configured to amplify the baseband signal; a fourth chopper configured to chop the amplified baseband signal at a second chopping frequency; and an analog-to-digital converter (ADC) configured to sample the amplified baseband signal for digitization.

[0017] In yet another aspect, a gyro sensor circuit includes a gyro sensor that generates an RF sensing signal according to an angular motion of the gyro sensor, and an RF sensing path configured to receive and process the RF sensing signal. The RF sensing path includes: a first chopper including a chopping switch and configured to chop an RF signal at a first chopping frequency to generate a chopping signal; a demodulator including an RF section and an LO section; a connection path configured to add an LO signal generated by an LO oscillator to the chopped RF signal to generate a combined signal; an LO mixer configured to mix the combined signal and the LO signal to generate a demodulated signal; and a baseband filter configured to receive the demodulated signal and pass a passband signal; and a feedback loop configured to feed back the baseband signal to the gyro sensor, the feedback loop including: a first amplifier configured to amplify the baseband signal to output an amplified baseband signal; a test voltage monitor configured to extract a component corresponding to the LO signal from the demodulated feedback signal and compare a voltage of the extracted component with an expected value determined based on a gain of the first amplifier; and a second chopper-modulator combination configured to chop the baseband signal at a second chopping frequency to output a modulated baseband signal.

[0018] The RF sensing path may further include a second amplifier configured to amplify the RF sensing signal.

[0019] The RF sensing path may further include: a third amplifier configured to amplify the baseband signal to output an amplified baseband signal; a third chopper configured to chop the amplified baseband signal at a first chopping frequency; and an analog-to-digital converter (ADC) configured to sample the amplified baseband signal to output a digitized baseband signal.

[0020] The RF sensing path may also include a digital signal processor (DSP) for analyzing the digitized baseband signal.

[0021] The DSP includes: a digital filter configured to extract a desired signal from a digitized baseband signal; and an amplitude detector configured to measure the amplitude of the desired signal.

[0022] The feedback loop may further include a fourth amplifier configured to amplify the modulated baseband signal.

[0023] The first amplifier and the second amplifier may be transconductance amplifiers, and the third amplifier and the fourth amplifier may be transimpedance amplifiers.

[0024] Other aspects, advantages and salient features of the present disclosure will become more apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the accompanying drawings, discloses exemplary embodiments of the present disclosure.

[0025] Before proceeding to the detailed description below, it may be helpful to set forth definitions of certain words and phrases used throughout this patent document: the terms "include" and "comprising" and their derivatives mean including but not limiting; the term "or" is inclusive, meaning "and / or"; the phrases "associated with" and "associated with" and their derivatives may mean including, (being) included within, interconnected with, contain, (being) contained within, connected to or connected with, coupled to or coupled with, communicable with, cooperating with, intertwined, side by side, adjacent to, (being) bound to or bound with, having, having the property of, etc.; and the term "controller" means any device, system, or part thereof that controls at least one operation, such device may be implemented in hardware, firmware, or software, or some combination of at least two thereof. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. Definitions of certain words and phrases are provided in this patent document, and those skilled in the art will appreciate that in many, if not most instances, such definitions apply to prior and future uses of such defined words and phrases. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 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, wherein like reference numerals represent like parts:

[0027] [ Figure 1 ] Figure 1 A gyroscopic sensor circuit for monitoring components in an FTR feedback loop is shown according to one embodiment of the present disclosure.

[0028] [ Figure 2 ] Figure 2 A gyroscopic sensor circuit for monitoring components in an RF sensing path is shown according to one embodiment of the present disclosure.

[0029] [ Figure 3 ] Figure 3 A gyro sensor circuit for monitoring a baseband component of an FTR feedback loop and an RF sensing path is shown according to one embodiment of the present disclosure.

[0030] Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures. DETAILED DESCRIPTION

[0031] The following discussion Figures 1 to 3And the various embodiments used to describe the principles of the present disclosure in this patent document are for illustration only and should not be interpreted as limiting the scope of the present disclosure in any way. Those skilled in the art will understand that the principles of the present disclosure can be implemented in any appropriately arranged system and method. The following description with reference to the accompanying drawings is provided to help fully understand the various embodiments of the present disclosure as defined by the claims and their equivalents. The following description includes various specific details to help understanding, but these specific details should be regarded as examples only. Therefore, those of ordinary skill in the art will recognize that various changes and modifications may be made to the various embodiments described herein without departing from the scope and spirit of the present disclosure. In addition, for the sake of clarity and brevity, the description of known functions and structures may be omitted.

[0032] It should be apparent to those skilled in the art that the following description of various embodiments of the present disclosure is provided for illustration purpose only and not for the purpose of limiting the present disclosure as defined by the appended claims and their equivalents.

[0033] Although ordinal numbers such as "first," "second," and the like are used to describe various components, those components are not limited herein. Such terms are only used to distinguish one component from another component. For example, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component without departing from the teachings of the present inventive concept.

[0034] The terms used herein are only for describing various embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms used herein are also intended to include the plural forms. It will be further understood that when used in this specification, the terms "including" and / or "having" represent the presence of the features, quantities, steps, operations, components, elements, or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, steps, operations, components, elements, or combinations thereof.

[0035] Figure 1 A gyro sensor circuit 100 for monitoring components in a forced rebalance (FTR) feedback loop is shown according to one embodiment of the present disclosure. Specifically, the gyro sensor circuit 100 monitors a framed region 10 in the FTR feedback loop 7 .

[0036] The gyro sensor circuit 100 includes: a gyro sensor 1 ; an RF sensing path 2 for processing an RF sensing signal generated from the gyro sensor 1 ; and an FTR feedback loop 7 for feeding back a portion of the RF sensing signal to the gyro sensor 1 .

[0037] The RF sensing path 2 may include a gyro sensor 1, a first amplifier 3, a first chopper 4, and a demodulator 5. The RF sensing path 2 may further include a fourth amplifier 12, a second chopper 13, and an ADC 14.

[0038] Initially, when the gyro sensor 1 moves at angular velocities in different directions, the gyro sensor 1 generates an RF signal according to the angular motion. Then, the generated RF signal is received by the RF path 2 and then amplified at the amplifier 3.

[0039] The amplified RF signal is coupled to a first chopper 4, which comprises a set of chopping switches for generating a chopped version of the RF signal at a first chopping frequency f_chp1. The chopped RF signal is supplied to a demodulator 5, which comprises an RF section 5a, an LO mixer section 5b and a baseband filter section 5c.

[0040] The RF section 5a includes an RF input transistor for providing a specific gain to the RF signal. In some embodiments, the gain of the RF input transistor does not need to have a specific value and may not be important for the performance of the system. The LO oscillator 6 generates a local oscillator signal (LO signal) having an LO frequency and supplies it to the LO mixer section 5b consisting of the LO switching transistor required for the mixing operation.

[0041] The LO mixer portion 5b receives a local oscillator signal (LO signal) having an LO frequency generated from the LO oscillator 6. Then, the LO mixer portion 5b multiplies the chopped combined signal by the LO signal, thereby generating a demodulated RF and baseband signal.

[0042] The baseband filter section 5c includes a low-pass filter for removing unnecessary signals from a frequency band occupied by the modulated RF signal at a given moment. Therefore, the demodulator 5 outputs a baseband signal that has passed through the low-pass filter in the baseband filter section 5c.

[0043] like Figure 1 As shown, the FTR feedback loop 7 branches off from the RF sensing path 2 at the output of the demodulator 5, and feeds back the baseband signal with a certain gain / attenuation to the gyro sensor 1. The baseband signal branched from the RF sensing path to the FTR feedback loop 7 is amplified at the amplifier 8. The FTR feedback loop 7 may also include a chopper re-modulator 9a coupled to the LO oscillator, a third amplifier 11, and a test voltage monitor 16.

[0044] In one embodiment, amplifier 11 is a transimpedance amplifier (TIA), and amplifiers 8 and 12 are transconductance amplifiers (gm cells).

[0045] In the FTR feedback loop 7, a connection path 15 is provided between the amplifier 8 and the chopper re-modulator 9a, and connects the LO oscillator 6 to the feedback loop 7. The connection path 15 may include a resistor, and provides an LO signal as an output test voltage. The LO signal is combined into a baseband signal, and the combined signal is supplied to the chopper re-modulator 9a.

[0046] The chopper re-modulator 9 a modulates the combined signal to a high frequency band by chopping the combined signal at the frequency of the LO signal. The modulated signal is amplified at the amplifier 11 and then fed back to the gyro sensor 1 .

[0047] The FTR feedback loop 7 also includes a test voltage monitor 16 that includes a low pass filter to extract a DC component of the combined signal that corresponds to the LO signal injected into the input of the chopper remodulator via path 15. The test voltage monitor 16 also includes a comparator for comparing the voltage of the extracted DC component with an expected value determined based on the gain of the chopper remodulator 9a and the gain of the amplifier 11. Thus, the test voltage monitor 16 can continuously check the electronic components of the FTR feedback loop block 10 to determine whether their performance deviates from their target values. Once an excessive deviation is detected, the test voltage monitor 16 can output a notification signal indicating the excessive deviation to the electronic system connected to the gyroscope sensor circuit 100.

[0048] Returning to the RF sensing path, the baseband signal is amplified by the amplifier 12 and then chopped by the second chopper 13 at a second chopping frequency.

[0049] If the same first and second chopping frequencies are selected, the desired gyroscope signal will be at DC after passing through the second chopper 13 , where it is supplied to an analog-to-digital converter (ADC) 14 , which samples the amplified baseband signal for digitization.

[0050] ADC 14 may be implemented in known converter circuits that generate a digital approximation of an analog signal sampled at a particular sampling frequency.

[0051] Figure 2 A gyro sensor circuit 200 for monitoring components in an RF sensing path 2 is shown according to one embodiment of the present disclosure. Specifically, the gyro sensor circuit 200 monitors a framed area 20 in the RF sensing path 2.

[0052] and Figure 1 Similarly, the gyro sensor circuit 200 includes a gyro sensor 1, an RF sensing path 2, and an FTR feedback loop 7. For the sake of brevity, repeated descriptions of the same components will be omitted.

[0053] The RF sensing path 2 may include a gyro sensor 1, an amplifier 3, a chopper 4, and a demodulator 5 including an RF section 5a, an LO mixer section 5b, and a baseband filter section 5c. The RF sensing path 2 also includes DC current generators 21a, 21b before the amplifier 3, and test voltage monitors 23a and 23b connected at, for example, a resistor provided between the RF section 5a and the LO mixer section 5b.

[0054] As described above, the gyro sensor 1 generates an RF signal according to angular motion in different directions. In addition, the DC current generators 21a, 21b generate a test DC current and supply the test DC current to the first chopper 22. Then, the chopper 22 chops the DC current at a first chopping frequency and supplies the chopped test DC current to the RF sensing path 2, wherein the chopped test DC current and the RF sensing signal are combined into a combined signal.

[0055] The first amplifier 3 amplifies the combined signal and provides the amplified signal to the chopper 4, which chops the combined signal at a first chopping frequency and outputs a chopped combined signal. In other words, the chopper 4 and the chopper 22 perform chopping operations at the same chopping frequency, so the corresponding test signal will reside at DC in the frequency domain.

[0056] The demodulator 5 includes an RF section 5a, an LO mixer section 5b and a baseband filter section 5c. Test voltage monitors 23a, 23b are provided between the RF section 5a and the LO mixer section 5b.

[0057] The test voltage monitors 23a, 23b extract respective components (DC) corresponding to the test DC currents from the chopped RF signal and compare the voltages of the extracted components with expected values ​​determined based on the gain of the amplifier 3 and the values ​​of the test DC currents 21a and 21b.

[0058] The LO mixer section 5b multiplies the chopped combined signal with the LO signal to output a demodulated signal. The baseband filter section 5c receives the demodulated signal and passes the baseband signal through a low pass filter. Note that the desired gyro signal is at the first chopping frequency at the output of the demodulator 5.

[0059] The FTR feedback loop 7 branches out from the RF sensing path 2 at the output of the demodulator 5, and feeds back the baseband signal with a certain gain / attenuation to the gyro sensor 1. The branched baseband signal is amplified at the amplifier 8 to output the feedback signal. The FTR feedback loop 7 may also include: a third chopping re-modulator combination 9b for chopping and modulating the feedback signal back to the RF frequency of the gyro sensor 1; and an amplifier 11 for amplifying the feedback signal before it is fed back to the gyro sensor 1.

[0060] The RF sensing path 2 may further include an amplifier 12 for amplifying the chopped baseband signal and a chopper 13 for chopping again at a second chopping frequency. If the first chopping frequency and the second chopping frequency are the same, the desired gyroscope sensor signal will be at DC in the frequency domain. The RF sensing path 2 may further include an ADC 12 for sampling the amplified baseband signal for digitization.

[0061] In one embodiment, amplifier 11 is a transimpedance amplifier (TIA), and amplifiers 8 and 12 are transconductance amplifiers (gm cells).

[0062] Figure 3 A gyro sensor circuit 300 of a baseband assembly for monitoring the FTR feedback loop 7 and the RF sensing path 2 according to one embodiment of the present disclosure is shown. Specifically, a framed area 30 extending over the FTR feedback loop 7 and the RF sensing path 2 of the gyro sensor circuit 300 is monitored.

[0063] and Figure 1 and Figure 2 Similarly, the gyro sensor circuit 300 includes a gyro sensor 1, an RF sensing path 2, and an FTR feedback loop 7. For the sake of brevity, repeated descriptions of the same components will be omitted.

[0064] The RF sensing path 2 includes the gyro sensor 1, the amplifier 3, the first chopper 4 and the demodulator 5, and the FTR feedback loop 7 includes the second amplifier 8, the second chopper 9c and the amplifier 11. In addition, a connection path 31 is added in the RF sensing path 2 to connect the LO oscillator 6 to the demodulator 5, and a test voltage monitor 32 is added in the FTR feedback loop 7.

[0065] Specifically, the connection path 31 is provided between the RF section 5a and the LO mixer section 5b in the demodulator 5. The connection path 31 may include a resistor and couple the LO signal to provide an output test voltage to the chopped RF signal, thereby generating a combined signal.

[0066] Subsequently, the LO mixer section 5b multiplies the combined signal with the LO signal to generate a baseband signal. The baseband filter section 5c comprises a low pass filter for passing the baseband signal. At the output of the demodulator 5, the test signal will be at DC and the gyro signal will be at the first chopping frequency.

[0067] In the FTR feedback loop 7, the baseband signal branches off the RF sensing path 2 at the output of the demodulator 5 and is amplified by the amplifier 8. The amplified baseband signal is chopped by the second chopper 9c at a first chopping frequency and then amplified at the amplifier 11 before being fed back to the gyro sensor 1.

[0068] The test voltage monitor 32 is connected, for example, at a resistor 32a provided between the second amplifier 8 and the second chopper 9c. The test voltage monitor 32 may include a low-pass filter to extract a DC component corresponding to the test signal injected through the path 31. The test voltage monitor 32 may compare the voltage of the extracted component with an expected value determined based on the gain of the amplifier 8 and the LO mixer portion of the demodulator 5.

[0069] The RF sensing path 2 may further include a fourth amplifier 12, a second chopper 13, and an ADC 14. The RF sensing path 2 may further include a digital signal processor (DSP) 33 for analyzing the digitized baseband signal. As an example, the DSP includes: a digital filter 33a for extracting a desired signal; and an amplitude detector 33b for measuring the amplitude of the desired signal. In one embodiment, the DSP 33 extracts a DC component corresponding to the gyroscope signal and a component at a first chopping frequency corresponding to the LO signal provided as an output test voltage, and compares the extracted test voltage with an expected value determined based on the gain of the amplifier 11.

[0070] Although the present disclosure has been described using example embodiments, various changes and modifications may be apparent to those skilled in the art. The present disclosure is intended to encompass such changes and modifications as fall within the scope of the appended claims.

Claims

1. A gyroscope sensor circuit, comprising: a gyro sensor, generating a radio frequency (RF) sensing signal according to the angular motion of the gyro sensor, An RF sensing path is configured to receive and process the RF sensing signal, the RF sensing path comprising: a first chopper including a chopping switch and configured to chop the RF signal at a first chopping frequency to generate a chopping signal; a demodulator coupled to a local oscillator (LO) signal generating the LO signal, the demodulator being configured to mix the chopped signal with the LO signal to output a baseband signal; and A feedback loop is configured to feed back the baseband signal to the gyro sensor, the feedback loop comprising: a connection path configured to connect the LO oscillator to the feedback loop, thereby providing the LO signal as a first output test voltage; a chopper re-modulator configured to chop and modulate the baseband signal at a frequency of the LO signal to generate a modulated feedback signal; A first amplifier configured to amplify the modulated feedback signal; and A test voltage monitor is configured to extract a component corresponding to the LO signal from the modulated feedback signal and compare a voltage of the extracted component with an expected value determined based on a gain of the first amplifier.

2. The gyro sensor circuit according to claim 1, wherein: The RF sensing path also includes a second amplifier configured to amplify the RF sensing signal.

3. The gyro sensor circuit according to claim 1, wherein: The demodulator comprises: RF part; an LO mixer configured to mix the chopped combined signal and the LO signal to output a demodulated signal; and The baseband filter is configured to receive the demodulated signal and pass a bandpass signal.

4. The gyro sensor circuit according to claim 1, wherein: Prior to the chopper re-modulator, the feedback loop further includes a third amplifier configured to amplify the baseband signal.

5. The gyro sensor circuit according to claim 4, wherein: The RF sensing path further comprises: a fourth amplifier configured to amplify the baseband signal; a second chopper configured to chop the amplified baseband signal at a second chopping frequency; The analog-to-digital converter ADC is configured to sample the amplified baseband signal for digitization.

6. The gyro sensor circuit according to claim 1, wherein: The first amplifier is a transimpedance amplifier.

7. The gyro sensor circuit according to claim 5, wherein: The third amplifier and the fourth amplifier are transconductance amplifiers.

8. A gyroscope sensor circuit comprising: a gyro sensor to generate an RF sensing signal based on angular movement of the gyro sensor; An RF sensing path is configured to receive and process the RF sensing signal, the RF sensing path comprising: a DC current generator configured to generate a test DC current; a first chopper configured to chop the DC current at a first chopping frequency and provide a chopped test DC current to the RF sensing path, wherein the chopped test DC current and the RF sensing signal are combined into a combined signal; a first amplifier configured to amplify the combined signal; a second chopper configured to chop the combined signal at a second chopping frequency to output a chopped combined signal; and Demodulator, including: RF part; a test voltage monitor configured to extract a component corresponding to a test DC current from the chopped combined signal and compare a voltage of the extracted component with an expected value determined based on a gain of the first amplifier; an LO mixer configured to mix the chopped combined signal and the LO signal to generate a modulated signal; and The baseband filter is configured to receive the modulated signal and pass a bandpass signal.

9. The gyro sensor circuit according to claim 8, wherein: The first chopper and the second chopper are configured to perform chopping operations at the same chopping frequency.

10. The gyro sensor circuit of claim 8, further comprising: A feedback loop is configured to feed back a baseband signal to the gyro sensor, the feedback loop comprising a chopping modulator configured to chop the baseband signal to output a modulated baseband signal.

11. The gyro sensor circuit according to claim 10, wherein: Prior to the chopper modulator, the feedback loop further comprises: The second amplifier is configured to amplify the baseband signal to output an amplified baseband signal.

12. The gyro sensor circuit according to claim 10, wherein: The feedback loop also includes a third amplifier configured to amplify the modulated baseband signal.

13. The gyro sensor circuit according to claim 12, wherein: The RF sensing path further comprises: a fourth amplifier configured to amplify the baseband signal; and The analog-to-digital converter ADC is configured to sample the amplified baseband signal for digitization.

14. A gyroscope sensor circuit comprising: a gyro sensor to generate an RF sensing signal based on angular movement of the gyro sensor; An RF sensing path is configured to receive and process the RF sensing signal, the RF sensing path comprising: a first chopper including a chopping switch and configured to chop the RF signal at a first chopping frequency to generate a chopping signal; Demodulator, including: RF part; a connection path configured to add an LO signal generated by the LO oscillator to the chopped RF signal to produce a combined signal; an LO mixer configured to mix the combined signal and the LO signal to generate a demodulated signal; and a baseband filter configured to receive the demodulated signal and pass a bandpass signal; and A feedback loop is configured to feed back a baseband signal to the gyro sensor, the feedback loop comprising: a first amplifier configured to amplify the baseband signal to output an amplified baseband signal; a test voltage monitor configured to extract a component corresponding to the LO signal from the modulated feedback signal and compare a voltage of the extracted component with an expected value determined based on a gain of the first amplifier; and The second chopping modulator is configured to chop the baseband signal at a second chopping frequency to output a modulated baseband signal.

15. The gyro sensor circuit according to claim 14, wherein: The RF sensing path also includes a second amplifier configured to amplify the RF sensing signal.

16. The gyro sensor circuit of claim 14, wherein: The RF sensing path further comprises: a third amplifier configured to amplify the baseband signal to output an amplified baseband signal; a third chopper configured to chop the amplified baseband signal at a third chopping frequency; and The analog-to-digital converter ADC is configured to sample the amplified baseband signal to output a digitized baseband signal.

17. The gyro sensor circuit of claim 16, wherein: The RF sensing path further comprises a digital signal processor DSP for analyzing the digitized baseband signal.

18. The gyro sensor circuit of claim 17, wherein: The DSP includes: A digital filter configured to extract a gyroscope desired signal and a test signal from the digitized baseband signal; and An amplitude detector is configured to measure the amplitude of the desired signal.

19. The gyro sensor circuit of claim 14, wherein: The feedback loop also includes a fourth amplifier configured to amplify the modulated baseband signal.

20. The gyro sensor circuit of claim 19, wherein: The first and second amplifiers are transconductance amplifiers, and the fourth amplifier is a transimpedance amplifier.

Images