Continuous monitoring of electronic devices in a forced rebalancing loop of gyro sensors

Abstract

The gyro sensor circuit includes a gyro sensor that generates an RF sense signal in response to angular movement and an RF sense path that receives and processes the RF sense signal. The RF sense path includes a first chopper that generates a chopper signal by chopping the RF signal at a first chopper frequency and a demodulator that outputs a baseband signal by mixing the chopper signal with an LO signal. The circuit further includes a chopper remodulator that chops and modulates the baseband signal at the frequency of the LO signal, a first amplifier that amplifies the modulated feedback signal, and a test voltage monitor that extracts a component corresponding to the LO signal from the modulated feedback signal and compares the voltage of the extracted component with an expected value determined based on the gain of the first amplifier.

Description

[Technical Field]

[0001] The present invention relates to a gyro sensor circuit that ensures a high performance closed-loop forced-to-rebalance system by continuously monitoring the function and accuracy of electronic components in the forced-to-rebalance forward and feedback paths. [Background technology]

[0002] Gyro sensors often employ a forced rebalance (FTR) feedback loop to eliminate the sensitivity of system gain and linearity to gyro gain, quality factor (Q), and linearity, and to increase the system bandwidth beyond that of open-loop gyroscopes.

[0003] With an FTR feedback loop, the feedback electronics control the end-to-end gain and linearity much better than with an open-loop sensing structure.

[0004] Gyroscope sensitivity is typically calibrated by the gyroscope supplier using a known set of rotational stimuli. However, sensitivity depends on a number of electromechanical properties that are sensitive to strain, change over the gyroscope's lifetime, or both. As a result, sensitivity may change after installation in an end-user's system or may drift over the gyroscope's lifetime. Because the actual input stimuli to the gyroscope after installation cannot be observed, it is conveniently difficult to recalibrate the gyroscope's sensitivity once the gyroscope is deployed in the field.

[0005] While this FTR feedback method has the advantage of incorporating a gyroscope in the monitoring of the system, it has the drawback of causing errors or false alarms if external rotations or other disturbances occur while the test signal is being applied, if these external rotations or disturbances have the same or similar frequency as the test signal. Therefore, a technique is needed that allows continuous monitoring without being affected by external mechanical or electrical disturbances to the gyro sensor. Summary of the Invention

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

[0007] A gyro sensor circuit with continuous monitoring capability avoids problems with test signals passing through the gyroscope, which can prevent proper operation in the presence of external signals or unwanted disturbances at the same frequency as the test signal.

[0008] In one aspect, the gyro sensor circuit includes a gyro sensor that generates an RF sense signal in response to angular movement, a radio frequency (RF) sense path that receives and processes the RF sense signal, the RF sense path including a first high-gain low-noise RF amplifier, a first chopper having a chopper switch that generates a chopped signal by chopping the RF signal at a first chopper frequency, and a demodulator coupled to a local oscillator (LO) that generates an LO signal and that outputs a baseband signal by mixing the chopped RF signal with the LO signal. The circuit further includes a feedback loop that feeds back a baseband signal to the gyro sensor, the feedback loop including a connection path used to remodulate the baseband signal to an RF frequency band by connecting an LO to the feedback loop, a second amplifier that operates to amplify the baseband signal, a complex chopper remodulator that chops and modulates the baseband signal at the frequency of the LO signal to generate a modulated feedback signal, a third amplifier that amplifies the modulated feedback signal to drive the gyro electrode, and a test voltage monitoring unit that extracts a DC component from the modulated feedback signal and compares the voltage of the extracted component with an expected value determined based on the gain of the third amplifier.

[0009] The RF detection path may further include a fourth amplifier that amplifies the baseband signal, a chopper that chops the amplified baseband signal at a chopper frequency, and an analog-to-digital converter (ADC) that samples 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 detection signal in response to angular movement and an RF detection path that receives and processes the RF detection signal. The RF detection path includes a DC current source that generates a test DC current, a first chopper that combines the chopper test current and the RF detection signal into a composite signal by chopping the DC current at a first chopper frequency and providing the chopper test current to the RF detection path, a first amplifier that amplifies the combined signal, a second chopper that chops the combined signal at a second chopper frequency to output a chopper composite signal, and a demodulator. The demodulator includes two RF and LO sections separated by a pair of resistors, and a test voltage monitor that extracts a component corresponding to the test DC current from the chopper composite signal via the pair of resistors and compares the voltage of the extracted component with an expected value determined based on the gain of the first amplifier. The LO section of the demodulator generates a demodulated signal by mixing the shifted composite signal with the LO signal. The demodulator also includes a baseband filter that receives the demodulated signal and passes a bandpass signal.

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

[0014] The gyro sensor circuit may further include a feedback loop that feeds back a baseband signal to the gyro sensor, the feedback loop having a complex chopper modulator that chops the baseband signal to output a modulated baseband signal.

[0015] The feedback loop may further comprise a third amplifier that amplifies the modulated baseband signal.

[0016] The RF detection path may further include a fourth amplifier that amplifies the baseband signal, a fourth chopper that chops the amplified baseband signal at a second chopper frequency, and an analog-to-digital converter (ADC) that samples the amplified baseband signal for digitization.

[0017] In yet another aspect, a gyro sensor circuit includes a gyro sensor that generates an RF sense signal in response to angular movement and an RF sense path that receives and processes the RF sense signal. The RF sense path includes a first chopper having a chopper switch that generates a chopped signal by chopping an RF signal at a first chopper frequency, an RF section and an LO section, a connection path that generates a composite signal by adding an LO signal generated by the LO to the chopped RF signal, an LO mixer that generates a demodulated signal by mixing the composite signal with the LO signal, and a demodulator that receives the demodulated signal and has a baseband filter that passes a bandpass signal. The gyro sensor circuit further includes a feedback loop that feeds back a baseband signal to the gyro sensor, the feedback loop including a first amplifier that amplifies the baseband signal to output an amplified baseband signal, a test voltage monitor that extracts a component corresponding to the LO signal from the demodulated feedback signal and compares the voltage of the extracted component with an expected value determined based on the gain of the first amplifier, and a second composite chopper modulator that chops the baseband signal at a second chopper frequency to output a modulated baseband signal.

[0018] The RF detection path may further include a second amplifier that amplifies the RF detection signal.

[0019] The RF detection path may further include a third amplifier that amplifies the baseband signal to output an amplified baseband signal, a third chopper that chops the amplified baseband signal at the first chopper frequency, and an analog-to-digital converter (ADC) that samples the amplified baseband signal to output a digital baseband signal.

[0020] The RF detection path may further comprise a digital signal processor (DSP) that analyzes the digital baseband signal.

[0021] The DSP may include a digital filter that extracts the desired signal from the digital baseband signal and an amplitude detector that measures the amplitude of the desired signal.

[0022] The feedback loop may further comprise a fourth amplifier that amplifies the modulated baseband signal.

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

[0024] Other aspects, advantages, and features of the present disclosure will become apparent to those skilled in the art from the following detailed description, in which illustrative embodiments of the present disclosure are described with reference to the accompanying drawings.

[0025] Before proceeding to the detailed description below, for convenience, terms and expressions used in this specification are defined as follows: The terms "include" and "comprise" and their derivatives mean inclusion without limitation. The term "or" is inclusive and means "and / or." The expressions "associated with" and "associated therewith" and their derivatives mean include, be included within, interconnect with, contain, be contained within, connect to or with, coupled to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, and the like. The term "controller" means any device, system, or portion thereof that controls at least one operation, and may be implemented in hardware, firmware, software, or a combination of at least two of these. It should be noted that the functionality associated with any particular controller may be centralized or decentralized, whether locally or indirectly. These definitions of terms and phrases are adopted herein, and those skilled in the art will understand that in many, if not most, cases, these definitions apply before and after the use of the terms and phrases. [Brief explanation of the drawings]

[0026] For a more detailed understanding of the present disclosure and its advantages, reference is now made to the accompanying drawings, in which like parts are numbered like, and in which: [Figure 1]FIG. 1 illustrates a gyro sensor circuit for monitoring components in an FTR feedback loop according to one embodiment of the present disclosure. [Figure 2] FIG. 2 illustrates a gyro sensor circuit for monitoring components in an RF sensing path according to one embodiment of the present disclosure. [Figure 3] FIG. 3 illustrates a gyro sensor circuit that monitors the baseband components of the FTR feedback loop and RF sensing path according to one embodiment of the present disclosure.

[0027] In the drawings, like reference numerals refer to the same or similar elements, features, and structures. DETAILED DESCRIPTION OF THE INVENTION

[0028] 1 to 3 described below, as well as various embodiments used herein to explain the principles of the present disclosure, are merely examples and are not to be construed 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, taken in conjunction with the accompanying drawings, will help to provide a comprehensive understanding of various embodiments of the present disclosure as set forth in the claims and their equivalents. While such descriptions include numerous specific details to aid in understanding, these are merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the various embodiments described herein without departing from the scope and spirit of the present disclosure. In addition, descriptions of well-known functions and configurations may be omitted for clarity and conciseness.

[0029] It will be apparent to those skilled in the art that the following description of various embodiments of the present disclosure is merely illustrative, and does not limit the disclosure as set forth in the appended claims and their equivalents.

[0030] Although ordinal numbers such as "first" and "second" are used to describe various components, these components are not limited herein. These terms are used only to distinguish one component from another. For example, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component, without departing from the concept of the invention.

[0031] The terms used herein are for the purpose of describing various embodiments only and are not intended to be limiting. As used herein, the singular forms "a," "an," and "the" include the plural forms unless the context clearly dictates otherwise. Furthermore, the terms "comprises" and / or "has," when used herein, specify the presence of stated features, numbers, steps, operations, components, elements, or combinations thereof, but do not exclude the presence or addition of one or more other features, numbers, steps, operations, components, elements, or combinations thereof.

[0032] 1 illustrates a gyro sensor circuit 100 for monitoring components in a force rebalance (FTR) feedback loop according to one embodiment of the present disclosure. In particular, the gyro sensor circuit 100 monitors a closed region 10 in an FTR feedback loop 7.

[0033] The gyro sensor circuit 100 includes a gyro sensor 1, an RF detection path 2 that processes an RF detection signal generated by the gyro sensor 1, and an FTR feedback loop 7 that feeds back a portion of the RF detection signal to the gyro sensor 1.

[0034] 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.

[0035] First, when the gyro sensor 1 moves in different directions at angular velocities, the gyro sensor 1 generates RF signals in response to the angular movements, and the generated RF signals are then received by the RF path 2 and amplified in the amplifier 3.

[0036] The amplified RF signal is coupled to a first chopper 4 comprising a set of chopper switches to generate a chopped RF signal at a first chopper frequency f_chp1, which is fed to a demodulator 5 comprising an RF section 5a, an LO mixer section 5b and a baseband filter section 5c.

[0037] The RF section 5a includes an RF input transistor and provides a specific gain to the RF signal. In some embodiments, the gain of the RF input transistor does not need to be a specific value and is not necessary for system performance. The LO 6 generates a local oscillator signal (LO signal) having an LO frequency, which is provided to the LO mixer section 5b, which includes an LO switching transistor required for the mixing operation.

[0038] LO mixer unit 5b receives a local oscillator signal (LO signal) having an LO frequency generated by LO 6. LO mixer unit 5b then generates demodulated RF and baseband signals by multiplying the chopper synthesis signal by the LO signal.

[0039] The baseband filter unit 5c includes a low-pass filter that removes unnecessary signals from the band of the modulated RF signal at a given moment, and as a result, the demodulator 5 outputs a baseband signal that has passed through the low-pass filter in the baseband filter unit 5c.

[0040] As shown in Figure 1, FTR feedback loop 7 branches off from RF sensing path 2 at the output of demodulator 5 and feeds back a baseband signal with a specific gain / attenuation to gyro sensor 1. The baseband signal branched from the RF sensing path to FTR feedback loop 7 is amplified by amplifier 8. FTR feedback loop 7 may further include a chopper remodulator 9a coupled to the LO, a third amplifier 11, and a test voltage monitor 16.

[0041] In one embodiment, amplifier 11 is a transimpedance amplifier (TIA) and amplifiers 8 and 12 are transconductance amplifiers (gm cells).

[0042] In the FTR feedback loop 7, a connection path 15 is disposed between the amplifier 8 and the chopper remodulator 9a and connects the LO 6 to the feedback loop 7. The connection path 15 may include a resistor and can provide the LO signal as an output test voltage. The LO signal is combined into a baseband signal and the combined signal is provided to the chopper remodulator 9a.

[0043] The chopper remodulator 9a modulates the composite signal to a high frequency band by chopping the composite signal at the frequency of the LO signal. The modulated signal is amplified by the amplifier 11 and fed back to the gyro sensor 1.

[0044] The FTR feedback loop 7 further includes a test voltage monitor 16, which includes a low-pass filter to extract a DC component of the composite signal, corresponding to the LO signal injected via path 15 to the input of the chopper remodulator. The test voltage monitor 16 also includes a comparator that compares 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 continuously monitors the electronic components in the FTR feedback loop region 10 to determine whether their performance deviates from the target value. If an excessive deviation is detected, the test voltage monitor 16 can output a notification signal to an electronic system connected to the gyro sensor circuit 100 indicating the excessive deviation.

[0045] Returning to the RF detection path, the baseband signal is amplified by amplifier 12 and chopped by second chopper 13 at a second chopper frequency.

[0046] If the same frequency is selected for the first and second chopper frequencies, the desired gyro signal will be DC after passing through the second chopper 13 and will be fed to an analog-to-digital converter (ADC) 14 which samples the amplified baseband signal for digitization.

[0047] ADC 14 may be implemented as a known conversion circuit that produces a digital approximation of an analog signal sampled at a particular sampling frequency.

[0048] 2 shows a gyro sensor circuit 200 monitoring components in an RF sensing path 2, according to one embodiment of the present disclosure. In particular, the gyro sensor circuit 200 monitors an enclosed area 20 in the RF sensing path 2.

[0049] 1, 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 identical components will be omitted.

[0050] The RF sensing path 2 may include a gyro sensor 1, an amplifier 3, a chopper 4, and a demodulator 5 having an RF section 5a, an LO mixer section 5b, and a baseband filter section 5c. The RF sensing path 2 further includes DC current sources 21a, 21b before the amplifier 3, and test voltage monitors 23a, 23b connected across a resistor, for example, located between the RF section 5a and the LO mixer section 5b.

[0051] As described above, the gyro sensor 1 generates RF signals in response to angular movements in different directions. DC current sources 21a and 21b generate test DC currents and supply the test DC currents to a first chopper 22. The chopper 22 then chops the DC currents at a first chopper frequency and supplies a chopper test DC current to an RF sensing path 2. The chopper test DC current and the RF sensing signal are combined into a combined signal.

[0052] The first amplifier 3 amplifies the composite signal and supplies the amplified signal to the chopper 4. The chopper 4 chops the composite signal at a first chopper frequency and outputs a chopped composite signal. In other words, the chopper 4 and the chopper 22 perform chopping operations at the same chopper frequency, so that the corresponding test signal exists at DC in the frequency domain.

[0053] The demodulator 5 includes an RF unit 5a, an LO mixer unit 5b, and a baseband filter unit 5c. The test voltage monitors 23a and 23b are disposed between the RF unit 5a and the LO mixer unit 5b.

[0054] The test voltage monitoring units 23a and 23b extract a component (DC) corresponding to the test DC current from the chopper RF signal and compare the voltage of the extracted component with an expected value determined based on the gain of the amplifier 3 and the values of the test DC currents 21a and 21b.

[0055] The LO mixer 5b multiplies the chopper synthesized signal by the LO signal to output a demodulated signal. The baseband filter 5c receives the demodulated signal and passes the baseband signal through a low-pass filter. The desired gyro signal has the first chopper frequency at the output of the demodulator 5.

[0056] The FTR feedback loop 7 branches off from the RF sensing path 2 at the output of the demodulator 5 and feeds back a baseband signal with a specific gain / attenuation to the gyro sensor 1. The branched baseband signal is amplified by an amplifier 8 and output as a feedback signal. The FTR feedback loop 7 may further include a third complex chopper remodulator 9b that chops the feedback signal and modulates it back to the RF frequency of the gyro sensor 1, and an amplifier 11 that amplifies the feedback signal before feeding it back to the gyro sensor 1.

[0057] The RF sensing path 2 may further include an amplifier 12 that amplifies the chopped baseband signal and a chopper 13 that chops it again at a second chopper frequency. If the first chopper frequency and the second chopper frequency are the same, the desired gyro sensor signal may be DC in the frequency domain. The RF sensing path 2 may additionally include an ADC 12 that samples the amplified baseband signal for digitization.

[0058] In one embodiment, amplifier 11 is a transimpedance amplifier (TIA) and amplifiers 8 and 12 are transconductance amplifiers (gm cells).

[0059] 3, in accordance with one embodiment of the present disclosure, a gyro sensor circuit 300 is shown monitoring the baseband components of the FTR feedback loop 7 and the RF sensing path 2. In particular, the gyro sensor circuit 300 monitors a closed region 30 extending across the FTR feedback loop 7 and the RF sensing path 2.

[0060] 1 and 2, 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 identical components will be omitted.

[0061] The RF detection path 2 includes a gyro sensor 1, an amplifier 3, a first chopper 4, and a demodulator 5, and the FTR feedback loop 7 includes a second amplifier 8, a second chopper 9c, and an amplifier 11. In addition, a connection path 31 is additionally provided to connect the LO 6 to the demodulator 5 in the RF detection path 2, and a test voltage monitor 32 is additionally provided in the FTR feedback loop 7.

[0062] Specifically, the connection path 31 is disposed between the RF section 5a and the LO mixer section 5b in the demodulator 5. The connection path 31 may have a resistor and generates a composite signal by coupling the LO signal and providing an output test voltage to the chopper RF signal.

[0063] Subsequently, the LO mixer unit 5b generates a baseband signal by multiplying the synthesized signal by the LO signal. The baseband filter unit 5c includes a low-pass filter that passes the baseband signal. At the output of the demodulator 5, the test signal is DC, while the gyro signal has the first chopper frequency.

[0064] In the FTR feedback loop 7, a baseband signal is tapped from the RF sensing path 2 at the output of the demodulator 5 and amplified by an amplifier 8. The amplified baseband signal is chopped at the first chopper frequency by a second chopper 9c and amplified by an amplifier 11 before being fed back to the gyro sensor 1.

[0065] The test voltage monitoring unit 32 is connected, for example, at a resistor 32a disposed between the second amplifier 8 and the second chopper 9c. The test voltage monitoring unit 32 may include a low-pass filter to extract a DC component corresponding to the test signal injected via the path 31. The test voltage monitoring unit 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 of the demodulator 5.

[0066] RF detection path 2 may further include a fourth amplifier 12, a second chopper 13, and an ADC 14. RF detection path 2 may also include a digital signal processor (DSP) 33 that analyzes the digital baseband signal. As an example, the DSP includes a digital filter 33a that extracts the desired signal and an amplitude detector 33b that measures the amplitude of the desired signal. In one embodiment, DSP 33 extracts a DC component corresponding to the gyro signal and a component having the first chopper frequency that corresponds to the LO signal provided as the output test voltage, and compares the extracted test voltage with an expected value determined based on the gain of amplifier 11.

[0067] Although the present disclosure has been described with exemplary embodiments, various changes and modifications will be suggested to those skilled in the art, and the present disclosure includes such changes and modifications that fall within the scope of the appended claims.

Claims

1. a gyro sensor that generates a radio frequency (RF) sense signal in response to angular movement; an RF detection path for receiving and processing the RF detection signal, a first chopper having a chopper switch for chopping the RF signal at a first chopper frequency to generate a chopper signal; an RF detection path having a demodulator coupled to a local oscillator (LO) that generates an LO signal and outputs a baseband signal by mixing the chopper signal with the LO signal; a feedback loop that feeds back the baseband signal to the gyro sensor, a connection path for connecting the LO to provide the LO signal as a first output test voltage; a chopper remodulator that chops and modulates the baseband signal at the frequency of the LO signal to generate a modulated feedback signal; a first amplifier for amplifying the modulated feedback signal; a feedback loop including a test voltage monitoring unit that extracts a component corresponding to the LO signal from the modulated feedback signal and compares the voltage of the extracted component with an expected value determined based on a gain of the first amplifier; Gyro sensor circuit.

2. The gyro sensor circuit of claim 1 , wherein the RF sensing path further comprises a second amplifier that amplifies the RF sensing signal.

3. The demodulator An RF section, an LO mixer that outputs a demodulated signal by mixing the chopper synthesized signal and the LO signal; 2. The gyro sensor circuit of claim 1, further comprising: a baseband filter that receives the demodulated signal and passes a bandpass signal.

4. The gyro sensor circuit of claim 1 , wherein the feedback loop further comprises a third amplifier that amplifies the baseband signal before the chopper remodulator.

5. The RF sensing path further comprises: a fourth amplifier that amplifies the baseband signal; a second chopper for chopping the amplified baseband signal at a second chopper frequency; and an analog-to-digital converter (ADC) that samples the amplified baseband signal for digitization.

6. The gyro sensor circuit of claim 1 , wherein the first amplifier is a transimpedance amplifier.

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

8. a gyro sensor that generates an RF sense signal in response to angular movement; an RF detection path for receiving and processing the RF detection signal, a DC current source for generating a test DC current; a first chopper that chops the DC current at a first chopper frequency and provides a chopper test DC current to the RF detection path, thereby combining the chopper test DC current and the RF detection signal into a combined signal; a first amplifier for amplifying the composite signal; a second chopper for chopping the composite signal at a second chopper frequency to output a chopped composite signal; An RF section, a test voltage monitoring unit that extracts a component corresponding to a test DC current from the chopper composite signal and compares the voltage of the extracted component with an expected value determined based on a gain of the first amplifier; an LO mixer that generates a modulated signal by mixing the chopper synthesis signal with the LO signal; an RF detection path having a demodulator that receives the modulated signal and a baseband filter that passes a bandpass signal; Gyro sensor circuit.

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

10. 9. The gyro sensor circuit of claim 8, further comprising a feedback loop that feeds back the baseband signal to the gyro sensor, the feedback loop having a chopper modulator that outputs a modulated baseband signal by chopping the baseband signal.

11. The feedback loop includes, before the chopper modulator: The gyro sensor circuit of claim 10 , further comprising a second amplifier that amplifies the baseband signal to output an amplified baseband signal.

12. The gyro sensor circuit of claim 10 , wherein the feedback loop further comprises a third amplifier that amplifies the modulated baseband signal.

13. The RF sensing path further comprises: a fourth amplifier that amplifies the baseband signal; and an analog-to-digital converter (ADC) that samples the amplified baseband signal for digitization.

14. a gyro sensor that generates an RF sense signal in response to angular movement; an RF detection path for receiving and processing the RF detection signal, a first chopper having a chopper switch for chopping the RF signal at a first chopper frequency to generate a chopper signal; An RF section, a connection path for generating a composite signal by adding an LO signal generated by an LO to the chopped RF signal; an LO mixer that generates a demodulated signal by mixing the composite signal with the LO signal; an RF detection path including a demodulator that receives the demodulated signal and has a baseband filter that passes bandpass signals; a feedback loop that feeds back the baseband signal to the gyro sensor, a first amplifier that amplifies the baseband signal and outputs an amplified baseband signal; a test voltage monitoring unit that extracts a component corresponding to the LO signal from the modulated feedback signal and compares a voltage of the extracted component with an expected value determined based on a gain of the first amplifier; a second chopper modulator that chops the baseband signal at a second chopper frequency to output a modulated baseband signal. Gyro sensor circuit.

15. The gyro sensor circuit of claim 14 , wherein the RF sensing path further comprises a second amplifier that amplifies the RF sensing signal.

16. The RF sensing path further comprises: a third amplifier that amplifies the baseband signal and outputs an amplified baseband signal; a third chopper for chopping the amplified baseband signal at a third chopper frequency; 15. The gyro sensor circuit of claim 14, further comprising: an analog-to-digital converter (ADC) that samples the amplified baseband signal to output a digital baseband signal.

17. 17. The gyro sensor circuit of claim 16, wherein the RF sensing path further comprises a digital signal processor (DSP) that analyzes the digital baseband signal.

18. The DSP a digital filter for extracting the desired gyro signal and the test signal from the digital baseband signal; 20. The gyro sensor circuit of claim 17, further comprising: an amplitude detector that measures the amplitude of the desired signal.

19. The gyro sensor circuit of claim 14 , wherein the feedback loop further comprises a fourth amplifier that amplifies the modulated baseband signal.

20. 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.

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