JP2019174368A - Circuit device, physical quantity measuring device, electronic apparatus, moving body, and phase adjustment method - Google Patents

Abstract

To provide a circuit device, a physical quantity measuring device, an electronic apparatus, a moving body and a phase adjustment method with which it is possible to adjust with high accuracy the phase of a sync signal that controls the synchronous detection of a detection signal.SOLUTION: A circuit device 100 includes a drive circuit 150, a feedback signal input terminal TDG, a detection circuit 140, a test signal input terminal TTI, a test circuit 130, and a phase adjustment circuit 110. In a first operation mode, the detection circuit 140 detects a physical quantity signal. In a second operation mode, a first test signal is inputted to the feedback signal input terminal TDG, and the test circuit 130 outputs a first input signal for test to a first input node NS1 on the basis of a second test signal inputted from the test signal input terminal TTI and outputs a second input signal for test to a second input node NS2. The second test signal has a prescribed phase relationship with respect to the first test signal.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a circuit device, a physical quantity measuring device, an electronic device, a moving body, a phase adjustment method, and the like.

  A physical quantity measuring device for detecting a physical quantity that changes due to an external factor is incorporated in an electronic device such as a digital camera or a smartphone or a moving body such as a car or an airplane. For example, gyro sensors that detect angular velocities are used for so-called camera shake correction, attitude control, GPS autonomous navigation, and the like.

  In the vibration type gyro sensor, a phenomenon called mechanical vibration leakage in which the drive vibration of the vibrator affects the detected vibration is known. Since the detection signal corresponding to the angular velocity and the vibration leakage signal generated by mechanical vibration leakage are 90 degrees out of phase, the vibration leakage signal can be removed by synchronous detection synchronized with the detection signal. However, when the phase of the synchronous detection is shifted, the vibration leakage signal is mixed with the detection signal after the synchronous detection, and the accuracy of the detection signal is lowered. For this reason, for example, in Patent Document 1, in a detection circuit of a vibration type gyro sensor, a correction signal having the same amplitude and the same phase as the vibration leakage signal is applied to the signal leakage signal in order to reduce the vibration leakage signal before synchronous detection. After adding to a differential relationship, or after adding a correction signal with the same amplitude and opposite phase as the vibration leak signal to the vibration leak signal, the influence of the vibration leak signal is reduced by performing synchronous detection. Is disclosed.

JP 2017-40566 A

  Even if a technique for reducing the vibration leakage signal itself from the detection signal as described above is used, it is difficult to reduce the influence of the vibration leakage signal if the phase of the synchronous detection is shifted.

  The synchronization signal for controlling the synchronous detection disclosed in Patent Document 1 is generated based on the signal from the drive circuit provided with the phase adjustment circuit. The phase adjustment of the phase adjustment circuit is performed by the vibrator. Therefore, there is no disclosure regarding highly accurate phase adjustment of the synchronization signal. That is, the conventional drive circuit and detection circuit have a problem that the influence of the vibration leakage signal cannot be reduced because there is no circuit for adjusting the phase of the synchronization signal with high accuracy.

  One embodiment of the present invention includes a driver circuit, a feedback signal input terminal connected to the driver circuit, a detection circuit including a first input node, a second input node, and a synchronous detection circuit, and a first detection A signal input terminal, a second detection signal input terminal, a test signal input terminal, the first input node, the second input node, the first detection signal input terminal, and the second detection signal input A test circuit connected to the terminal and the test signal input terminal, and a phase adjustment circuit, wherein switching between a first operation mode and a second operation mode is possible, and in the first operation mode, The drive circuit outputs a drive signal for driving the physical quantity transducer based on the feedback signal from the physical quantity transducer input to the feedback signal input terminal, The phase adjustment circuit adjusts the phase of the signal from the drive circuit based on the feedback signal, and outputs the signal after phase adjustment to the synchronous detection circuit as a synchronization signal. The first detection signal from the physical quantity transducer input to the detection signal input terminal is output to the first input node, and the second detection signal input to the second detection signal input terminal is output to the first detection node. Output to the second input node, the synchronous detection circuit performs detection processing based on the first detection signal and the second detection signal, the detection circuit based on the output signal of the synchronous detection circuit Detecting a physical quantity signal, and in the second operation mode, the phase adjustment circuit receives a signal from the drive circuit based on the first test signal input to the feedback signal input terminal. And the phase adjusted signal is output to the synchronous detection circuit as a synchronization signal, and the test circuit outputs a first signal based on the second test signal input from the test signal input terminal. And a second test input signal is output to the second input node, and the second test signal is output with respect to the first test signal. The synchronous detection circuit performs detection processing based on the first test input signal and the second test input signal, and the detection circuit includes the synchronous detection circuit. The present invention relates to a circuit device that outputs a signal based on the output signal.

  In one embodiment of the present invention, the test circuit includes a first switch provided between the first input node and the first node, and between the second input node and the second node. A second switch provided between the first node and the third node, a second capacitor provided between the first node and the third node, and a second capacitor provided between the second node and the third node. Capacitor, a third switch provided between the third node and the test signal input terminal, and a fourth switch provided between the first input node and the first detection signal input terminal. And a fifth switch provided between the second input node and the second detection signal input terminal.

  In the aspect of the invention, the given phase relationship may be a phase relationship in which a phase difference between the first test signal and the second test signal is 90 degrees.

  In one embodiment of the present invention, the detection circuit includes an output terminal, and the detection circuit amplifies signals input to the first input node and the second input node, and an output signal of the synchronous detection circuit A low-pass filter that performs low-pass filter processing on the output circuit, the synchronous detection circuit performs detection processing on the output signal of the amplifier circuit, and the output terminal is connected to the low-pass filter in the second operation mode. An output signal of the filter may be output.

  Moreover, in one aspect of the present invention, a storage unit that stores the setting data of the phase adjustment may be included.

  In one aspect of the present invention, the phase adjustment circuit includes a delay circuit that delays a signal from the drive circuit, outputs the synchronization signal based on an output signal of the delay circuit, and the setting data includes: Data for setting a delay time of the delay circuit may be used.

  In one embodiment of the present invention, the detection circuit includes a second phase adjustment circuit that outputs a second synchronization signal based on a signal from the drive circuit and adjusts the phase of the second synchronization signal. An amplification circuit that amplifies signals input to the first input node and the second input node, and performs a detection process on the output signal of the amplification circuit based on the synchronization signal, and converts the physical quantity signal to A first synchronous detection circuit for extracting, and a second synchronous detection circuit for extracting a vibration leakage signal by performing detection processing on the output signal of the amplifier circuit based on the second synchronous signal. Also good.

  In the aspect of the invention, the given phase relationship may be a phase relationship in which a phase difference between the first test signal and the second test signal is 0 degree or 180 degrees. .

  In one embodiment of the present invention, the first low-pass filter includes a first output terminal and a second output terminal, and the detection circuit performs low-pass filter processing on an output signal of the first synchronous detection circuit. And a second low-pass filter that performs low-pass filter processing on the output signal of the second synchronous detection circuit, and the first output terminal in the second operation mode is the first low-pass filter. An output signal of the low-pass filter may be output, and the second output terminal may output an output signal of the second low-pass filter in the second operation mode.

  Another aspect of the invention relates to a physical quantity measuring device including any one of the circuit devices described above and the physical quantity transducer.

  Still another embodiment of the present invention relates to an electronic apparatus including any one of the circuit devices described above and a processing device that performs signal processing based on the physical quantity signal.

  Still another embodiment of the present invention relates to a moving body including any of the circuit devices described above and a body provided with the circuit device.

  According to still another aspect of the present invention, there is provided a phase adjustment method for the circuit device according to any one of the above, wherein the second operation mode is set during a test, and the first test signal is set to the feedback signal input terminal. A phase adjustment method for inputting the second test signal to the test signal input terminal, monitoring a detection result from the detection circuit, and obtaining setting data for the phase adjustment based on the detection result Related to.

2 shows a configuration example of a physical quantity measuring device and a circuit device. The figure explaining operation | movement of the synchronous detection circuit which detects an angular velocity signal. The figure explaining operation | movement of the synchronous detection circuit which detects a vibration leak signal. An example of a connection configuration between a circuit device and a test device during a test. 1 is a first detailed configuration example of a phase adjustment circuit. The figure explaining the temperature dependence of phase adjustment. 2 shows a second detailed configuration example of a phase adjustment circuit. The figure explaining the temperature characteristic of the adjusted delay time. The flowchart which shows the procedure of phase adjustment. The figure explaining a phase adjustment method. The figure explaining a phase adjustment method. Configuration example of an electronic device. An example of a moving object.

  Hereinafter, preferred embodiments of the present invention will be described in detail. The present embodiment described below does not unduly limit the contents of the present invention described in the claims, and all the configurations described in the present embodiment are indispensable as means for solving the present invention. Not necessarily.

  Hereinafter, a case where the physical quantity measuring device 400 is a gyro sensor will be described as an example. However, an application target of the present invention is not limited to a gyro sensor. That is, the present invention can be applied to any physical quantity measuring apparatus that drives a physical quantity transducer with a drive signal and synchronously detects a detection signal from the physical quantity transducer.

1. FIG. 1 is a configuration example of a physical quantity measuring device 400 and a circuit device 100. The physical quantity measuring device 400 includes the vibrator 10 and the circuit device 100.

  The vibrator 10 is a physical quantity transducer that converts an angular velocity on the detection axis into an electric signal. That is, the Coriolis force acts on the vibrator 10 due to the rotation component on the detection axis of the rotation of the vibrator 10, and the vibrator 10 detects the Coriolis force and outputs a signal corresponding to the Coriolis force. The vibrator 10 is a so-called piezoelectric vibrator in which an electrode is disposed on a piezoelectric body or a piezoelectric thin film is disposed on a silicon vibrator, for example. For example, the vibrator 10 is a double T-shaped, T-shaped, tuning fork type crystal vibrator, or the like. The vibrator 10 may be an electrostatic vibrator, or a MEMS (Micro Electro Mechanical Systems) vibrator as a silicon vibrator formed using a silicon substrate. Also good. The vibrator 10 is also called an angular velocity detection element, an angular velocity transducer, or a gyro sensor element.

  The circuit device 100 drives the vibrator 10 and extracts a physical quantity signal from the detection signal output from the vibrator 10. The circuit device 100 is constituted by an integrated circuit device, for example. The physical quantity measuring device 400 is configured by housing the circuit device 100 and the vibrator 10 in a package. The circuit device 100 includes a phase adjustment circuit 110, a phase adjustment circuit 120, a test circuit 130, a detection circuit 140, a drive circuit 150, a second test circuit 160, an interface circuit 170, and a storage unit 180. The circuit device 100 includes detection signal input terminals TS1, TS2, a drive signal output terminal TDS, a feedback signal input terminal TDG, an interface terminal TIF, a test signal input terminal TTI, output terminals TTQ1, TTQ2, and delay test terminals TPI, TPQ. including.

  The drive circuit 150 outputs a drive signal for driving the vibrator 10 based on the feedback signal DG from the vibrator 10. The drive circuit 150 includes a current / voltage conversion circuit 151, a drive signal generation circuit 152, and synchronous detection clock generation circuits 153 and 154.

  The current-voltage conversion circuit 151 converts the feedback signal DG that is a current signal from the vibrator 10 into a voltage signal IVQ. The current-voltage conversion circuit 151 can be configured by an operational amplifier, and a resistor and a capacitor that feed back the output of the operational amplifier.

  The drive signal generation circuit 152 outputs a drive signal DS based on the signal IVQ. The drive signal generation circuit 152 automatically controls the gain of the oscillation loop. That is, the signal IVQ is monitored to control the amplitude of the drive signal DS. The drive signal generation circuit 152, for example, a full-wave rectifier that performs full-wave rectification of the signal IVQ, an integrator that performs integration processing of the output signal of the full-wave rectifier, converts the signal IVQ into a drive signal DS, and outputs the integrator And a comparator that changes the amplitude of the drive signal DS in accordance with the signal.

  The drive signal output terminal TDS is connected to the first drive terminal of the vibrator 10 and outputs the drive signal DS from the drive signal generation circuit 152 to the vibrator 10. The feedback signal input terminal TDG is connected to the second drive terminal of the vibrator 10 and receives the feedback signal DG from the vibrator 10. The feedback signal DG input to the feedback signal input terminal TDG is input to the current-voltage conversion circuit 151.

  The synchronous detection clock generation circuit 153 generates a synchronous detection clock SDET1 having the same phase as the feedback signal DG based on the signal IVQ. The synchronous detection clock generation circuit 153 can be configured by, for example, an RC filter that performs high-pass filtering on the signal IVQ, and a comparator that converts the output signal of the RC filter into the synchronous detection clock SDET1.

  The synchronous detection clock generation circuit 154 generates a synchronous detection clock SDET2 that is 90 degrees out of phase with the feedback signal DG based on the signal IVQ. The synchronous detection clock generation circuit 154 can be configured by, for example, a filter circuit that shifts the phase of the signal IVQ by 90 degrees and a comparator that converts the output signal of the filter circuit into the synchronous detection clock SDET2.

  The phase adjustment circuit 110 outputs the synchronization signal SYC1 of the synchronous detection performed by the detection circuit 140 based on the signal from the drive circuit 150 and adjusts the phase of the synchronization signal SYC1. The phase adjustment circuit 110 is a first phase adjustment circuit. The synchronization signal SYC1 is a first synchronization signal. Specifically, the phase adjustment circuit 110 shifts the phase of the synchronous detection clock SDET1, and outputs a signal obtained by shifting the phase as the synchronous signal SYC1. The synchronization signal SYC1 is a synchronization signal for synchronously detecting the angular velocity signal included in the detection signal. The amount of phase shift is set based on the setting data PSD1 stored in the storage unit 180. The setting data PSD1 is acquired when the circuit device 100 is inspected using a method described later. The storage unit 180 is a semiconductor memory, for example, a nonvolatile memory.

  The phase adjustment circuit 120 outputs the synchronization signal SYC2 of the synchronous detection performed by the detection circuit 140 based on the signal from the drive circuit 150 and adjusts the phase of the synchronization signal SYC2. The phase adjustment circuit 120 is a second phase adjustment circuit. The synchronization signal SYC2 is a second synchronization signal. Specifically, the phase adjustment circuit 120 shifts the phase of the synchronous detection clock SDET2, and outputs a signal obtained by shifting the phase as the synchronous signal SYC2. The synchronization signal SYC2 is a synchronization signal for synchronously detecting a vibration leakage signal included in the detection signal. The amount of phase shift is set based on the setting data PSD2 stored in the storage unit 180. The setting data PSD2 is acquired when the circuit device 100 is inspected using a method described later.

  The detection signal input terminal TS1 is connected to the first detection terminal of the vibrator 10, and the detection signal S1 is input from the vibrator 10 to the detection signal input terminal TS1. The detection signal input terminal TS2 is connected to the second detection terminal of the vibrator 10, and the detection signal S2 is input from the vibrator 10 to the detection signal input terminal TS2. The detection signal input terminal TS1 is a first detection signal input terminal, and the detection signal input terminal TS2 is a second detection signal input terminal. The detection signal S1 is a first detection signal, and the detection signal S2 is a second detection signal. The detection signals S1 and S2 are differential signals. The test circuit 130 outputs the detection signals S1 and S2 input to the detection signal input terminals TS1 and TS2 to the detection circuit 140 in the first operation mode. The first operation mode is a mode set at a time other than the test time. For example, when the physical quantity measuring device 400 as a product performs a normal operation and detects a physical quantity, the time other than the test is used. Details of the test circuit 130 will be described later.

  The detection signal S1 is input to the input node NS1 of the detection circuit 140, and the detection signal S2 is input to the input node NS2 of the detection circuit 140. The input node NS1 is a first input node, and the input node NS2 is a second input node. The detection circuit 140 detects a physical quantity signal corresponding to the physical quantity based on the detection signals S1 and S2. That is, an angular velocity signal corresponding to the angular velocity is detected based on the detection signals S1 and S2. The physical quantity signal is an analog signal or a digital signal whose signal value changes according to the physical quantity applied to the physical quantity transducer. The detection circuit 140 includes an amplification circuit 141, synchronous detection circuits 142 and 144, low-pass filters 143 and 145, a multiplexer 146, an A / D conversion circuit 147, and a processing circuit 148.

  The amplifier circuit 141 amplifies signals input to the input nodes NS1 and NS2. When the test is not performed, the detection signals S1 and S2 are input to the input nodes NS1 and NS2, and the amplifier circuit 141 amplifies the detection signals S1 and S2. Specifically, the detection signals S1 and S2, which are charge signals, are converted into a voltage output signal QVQ. The output signal QVQ is a differential signal. The amplifier circuit 141 can be composed of an operational amplifier and a capacitor that feeds back the output of the operational amplifier.

  The synchronous detection circuit 142 performs detection processing on the output signal QVQ of the amplifier circuit 141. The synchronous detection circuit 142 is a first synchronous detection circuit. Specifically, the synchronous detection circuit 142 detects an angular velocity component from the output signal QVQ based on the synchronous signal SYC1. The synchronous detection circuit 142 can be configured by a switch circuit. The switch circuit outputs the polarity of the output signal QVQ, which is a differential signal, in a non-inverted manner when the synchronization signal SYC1 is at the first logic level, and is a differential signal when the synchronization signal SYC1 is at the second logic level. The polarity of the output signal QVQ is inverted and output.

  The low-pass filter 143 smoothes the output signal of the synchronous detection circuit 142 by performing low-pass filter processing on the output signal of the synchronous detection circuit 142. The low pass filter 143 is a first low pass filter. The output signal LPQ1 of the low pass filter 143 is a differential signal. The low-pass filter 143 is an RC filter composed of, for example, a resistor and a capacitor.

  The synchronous detection circuit 144 performs detection processing on the output signal QVQ of the amplifier circuit 141. The synchronous detection circuit 144 is a second synchronous detection circuit. Specifically, the synchronous detection circuit 144 detects a vibration leakage component from the output signal QVQ based on the synchronous signal SYC2. The synchronous detection circuit 144 can be configured by a switch circuit. The switch circuit outputs the polarity of the output signal QVQ, which is a differential signal, in a non-inverted manner when the synchronization signal SYC2 is at the first logic level, and is a differential signal when the synchronization signal SYC2 is at the second logic level. The polarity of the output signal QVQ is inverted and output.

  The low-pass filter 145 smoothes the output signal of the synchronous detection circuit 144 by performing low-pass filter processing on the output signal of the synchronous detection circuit 144. The low-pass filter 145 is a second low-pass filter. The output signal LPQ2 of the low pass filter 145 is a differential signal. The low-pass filter 145 is an RC filter composed of, for example, a resistor and a capacitor.

  The multiplexer 146 selects the output signal LPQ1 of the low-pass filter 143 or the output signal LPQ2 of the low-pass filter 145 in a time division manner, and outputs the selected signal to the A / D conversion circuit 147. For example, the output signals LPQ1 and LPQ2 are alternately selected. The multiplexer 146 can be configured by a switch circuit.

  The A / D conversion circuit 147 A / D converts the output signal of the multiplexer 146 and outputs the result as A / D conversion data. The A / D conversion circuit 147 A / D-converts the output signals LPQ1 and LPQ2 in time division in accordance with the timing at which the multiplexer 146 outputs the output signals LPQ1 and LPQ2 in time-division. That is, the A / D conversion circuit 147 outputs the A / D conversion data of the angular velocity signal and the A / D conversion data of the vibration leakage signal in a time division manner. As the A / D conversion method, for example, a successive approximation type, a flash type, a pipeline type, or a double integration type can be adopted.

  The processing circuit 148 processes the A / D conversion data of the output signal LPQ1 to generate angular velocity data, and processes the A / D conversion data of the output signal LPQ2 to generate vibration leakage data. For example, zero point correction processing, sensitivity correction processing, low-pass filter processing, and the like are performed on the A / D conversion data of the output signal LPQ1. Further, low-pass filter processing or the like is performed on the A / D conversion data of the output signal LPQ2. The processing circuit 148 monitors the vibration leakage data and performs failure detection. That is, when the signal value indicated by the vibration leakage data is small, a failure flag indicating that a failure has occurred is generated. The failure is, for example, that the signal transmission path from the vibrator 10 to the output of the amplifier circuit 141 is broken. The processing circuit 148 is a logic circuit that performs digital signal processing. For example, the processing circuit 148 is a DSP (Digital Signal Processor).

  The interface circuit 170 performs communication between the circuit device 100 and an external device. The external device is a processing device such as a CPU, a microprocessor, or SoC, for example. The interface circuit 170 transmits the angular velocity data and the failure flag from the processing circuit 148 to the external device. The interface circuit 170 receives setting information of the circuit device 100 from an external device. The interface circuit 170 includes an access circuit for the storage unit 180, and the storage unit 180 can be accessed from the external device via the interface circuit 170. As the communication method, for example, an SPI (Serial Peripheral Interface) method, an I2C (Inter-Integrated Circuit) method, or the like can be adopted. The interface circuit 170 and an external device are connected via an interface terminal TIF. Although one terminal is shown as the interface terminal TIF in FIG. 1, a necessary number of interface terminals are provided according to the communication method.

  FIG. 2 is a diagram illustrating the operation of the synchronous detection circuit 142 that detects the angular velocity signal. The feedback signal DG is a sine wave signal. The phase zero of the sine wave signal is used as a phase reference, and one cycle of the sine wave signal is 360 degrees.

  The synchronous detection clock SDET1 is a rectangular wave signal in phase with the feedback signal DG. The phase adjustment circuit 110 delays the phase of the synchronous detection clock SDET1 by 180 degrees, and outputs the delayed signal as the synchronization signal SYC1. The synchronization signal SYC1 has a phase opposite to that of the feedback signal DG. Since the detection signals S1 and S2 are differential signals, S1-S2 is also referred to as a detection signal below. The detection signals S1-S2 include an angular velocity signal SAR and a vibration leakage signal SML. In FIG. 2, these are shown separately, but in reality, a signal obtained by adding SAR and SML is a detection signal. The angular velocity signal SAR is a sine wave signal, and its phase is delayed by 90 degrees with respect to the feedback signal DG. The vibration leakage signal SML is a sine wave signal and is in phase with the feedback signal DG.

  The amplifier circuit 141 amplifies the detection signal S1-S2. At this time, the phase of the output signal QVQ of the amplifier circuit 141 advances by 90 degrees with respect to the detection signal S1-S2. Therefore, the angular velocity signal SAR 'included in the output signal QVQ is in phase with the synchronization signal SYC1, and the vibration leakage signal SML' is 90 degrees out of phase with the synchronization signal SYC1. When the synchronous detection circuit 142 synchronously detects the output signal QVQ based on the synchronous signal SYC1, an in-phase angular velocity signal SAR ′ is extracted with respect to the synchronous signal SYC1, and a vibration leakage signal SML whose phase is 90 degrees different from that of the synchronous signal SYC1. 'Is reduced.

  However, when the phase difference between the synchronization signal SYC1 and the vibration leakage signal SML ′ is shifted from 90 degrees, the signal after the synchronous detection includes the vibration leakage signal. In the conventional configuration, since there is no means for monitoring the phase difference between the synchronization signal SYC1 and the vibration leakage signal SML ', for example, the phase of the synchronization signal is determined so that the detection sensitivity of the gyro sensor is near the maximum. However, since the detection signals S1 to S2 are not always perfect sine waves, the phase difference between the synchronization signal SYC1 and the vibration leakage signal SML 'is not always exactly 90 degrees when the sensitivity is maximum. In the present embodiment, the phase of the synchronization signal SYC1 can be adjusted with high accuracy by performing phase adjustment using the test signal input terminal TTI and the test circuit 130, and a vibration leakage signal with higher accuracy than in the past. SML ′ can be reduced. This phase adjustment method will be described later.

  FIG. 3 is a diagram for explaining the operation of the synchronous detection circuit 144 that detects the vibration leakage signal. The feedback signal DG, the detection signals S1-S2, and the output signal QVQ of the amplifier circuit 141 are the same as those in FIG.

  The synchronous detection clock SDET2 is a rectangular wave signal whose phase is advanced by 90 degrees with respect to the feedback signal DG. The phase adjustment circuit 120 delays the phase of the synchronous detection clock SDET2 by 180 degrees, and outputs the delayed signal as a synchronous signal SYC2. The phase of the synchronization signal SYC2 is delayed by 90 degrees with respect to the feedback signal DG. The angular velocity signal SAR 'included in the output signal QVQ is 90 degrees out of phase with the synchronization signal SYC2, and the vibration leakage signal SML' is in phase with the synchronization signal SYC2. When the synchronous detection circuit 144 synchronously detects the output signal QVQ based on the synchronous signal SYC2, the in-phase vibration leakage signal SML ′ is extracted from the synchronous signal SYC2, and the angular velocity signal SAR whose phase is 90 degrees different from that of the synchronous signal SYC2. 'Is removed.

  Since the angular velocity signal changes according to the angular velocity applied to the vibrator 10, the vibration leakage signal fluctuates when the angular velocity signal is included in the vibration leakage signal after synchronous detection. If the vibration leakage signal fluctuates, there is a possibility of affecting the failure detection using the vibration leakage signal. In the present embodiment, the phase of the synchronization signal SYC2 can be adjusted with high accuracy by performing phase adjustment using the test signal input terminal TTI and the test circuit 130, and the angular velocity signal SAR ′ can be reduced with high accuracy. Is possible. This phase adjustment method will be described later.

  FIG. 4 is a connection configuration example of the circuit device 100 and the test device 600 during the test. Although some of the components of the circuit device 100 are omitted for the sake of illustration, the configuration of the circuit device 100 is the same as that of FIG. The test is a test of the circuit device 100. For example, a test of the circuit device 100 in a wafer state can be assumed.

  As shown in FIG. 4, the test apparatus 600 includes a test signal generation circuit 610, a monitor circuit 620, a processing circuit 630, and a delay measurement circuit 640.

  The test signal STE1 is input to the feedback signal input terminal TDG. A test signal STE2 for measuring an adjustment value for phase adjustment is input to the test signal input terminal TTI. The test signal STE1 is a first test signal, and the test signal STE2 is a second test signal. The test signal STE2 is a signal having a given phase relationship with respect to the test signal STE1.

  Specifically, the test signal generation circuit 610 generates test signals STE1 and STE2. The test signal generation circuit 610 includes a voltage generation circuit VTG1 that generates a sine wave voltage, a resistor RG and a capacitor CG that convert the sine wave voltage into a current and outputs the current as a test signal STE1, and a test signal STE2 that is a sine wave voltage. And a voltage generation circuit VTG2 to be generated. The test signal generation circuit 610 controls the phase relationship between the test signals STE1 and STE2 by controlling the voltage generation circuits VTG1 and VTG2.

  The test circuit 130 is provided between the test signal input terminal TTI and the input nodes NS1 and NS2. In the second operation mode, the test circuit 130 inputs the test input signal TIS1 to the input node NS1 based on the test signal STE2, and outputs the test input signal TIS2 to the input node NS2. The test input signal TIS1 is a first test input signal, and the test input signal TIS2 is a second test input signal. The second operation mode is a mode set during the test. The first operation mode and the second operation mode are set based on setting information stored in a register (not shown), for example. This setting information is set in a register from the outside of the circuit device 100 via the interface circuit 170, for example. For example, the first operation mode is a default setting, and the processing circuit 630 in FIG. 4 sets the second operation mode in a register during a test.

  The test input signals TIS1 and TIS2 are in-phase signals, but their amplitudes are different. For this reason, TIS1-TIS2 when considered as a differential signal has a non-zero amplitude. Hereinafter, TIS1-TIS2 are also referred to as test input signals. The test input signals TIS1-TIS2 are charge signals, and their phases are different by 90 degrees with respect to the test signal STE2. That is, the phase relationship between the test signal STE1 and the test input signals TIS1-TIS2 can be set by setting the test signals STE1 and STE2 to a given phase relationship.

  In the above embodiment, the circuit device 100 includes the drive circuit 150, the feedback signal input terminal TDG connected to the drive circuit 150, the detection circuit 140, the detection signal input terminals TS1 and TS2, and the test signal input terminal TTI. , A test circuit 130 and a phase adjustment circuit 110. The detection circuit 140 includes input nodes NS 1 and NS 2 and a synchronous detection circuit 142. The test circuit 130 is connected to the input nodes NS1 and NS2, the detection signal input terminals TS1 and TS2, and the test signal input terminal TTI. The circuit device 100 can be switched between the first operation mode and the second operation mode. In the first operation mode, the drive circuit 150 outputs a drive signal DS for driving the vibrator 10 based on the feedback signal DG from the vibrator 10 input to the feedback signal input terminal TDG. The phase adjustment circuit 110 adjusts the phase of the signal from the drive circuit 150 based on the feedback signal DG, and outputs the signal after the phase adjustment to the synchronous detection circuit 142 as the synchronization signal SYC1. The test circuit 130 outputs the detection signals S1 and S2 from the vibrator 10 input to the detection signal input terminals TS1 and TS2 to the input nodes NS1 and NS2. The synchronous detection circuit 142 performs detection processing based on the detection signals S1 and S2. The detection circuit 140 detects a physical quantity signal based on the output signal of the synchronous detection circuit 142. In the second operation mode, the phase adjustment circuit 110 performs phase adjustment on the signal from the drive circuit 150 based on the test signal STE1 input to the feedback signal input terminal TDG, and uses the signal after phase adjustment as the synchronization signal SYC1. Output to the synchronous detection circuit 142. The test circuit 130 outputs test input signals TIS1 and TIS2 to the input nodes NS1 and NS2 based on the test signal STE2 input from the test signal input terminal TTI. The test signal STE2 is a signal having a given phase relationship with respect to the test signal STE1. The synchronous detection circuit 142 performs detection processing based on the test input signals TIS1 and TIS2. The detection circuit 140 outputs a signal based on the output signal of the synchronous detection circuit 142.

  According to the present embodiment, during the test, the test signal STE1 that simulates the feedback signal DG from the vibrator 10 can be input to the feedback signal input terminal TDG. Further, by providing the test signal input terminal TTI and the test circuit 130 and providing the second operation mode, the test input signals TIS1-TIS2 simulating the detection signals S1-S2 from the vibrator 10 are input to the detection circuit 140. it can. The phase relationship between the test signal STE1 and the test input signals TIS1-TIS2 can be arbitrarily set by the test apparatus 600. That is, a signal simulating a vibration leakage signal can be input to the detection circuit 140 as the test input signals TIS1-TIS2. Thereby, the phase of the synchronization signal SYC1 can be accurately adjusted.

  Specifically, the processing circuit 630 reads the angular velocity data via the interface circuit 170 in a state where the test input signals TIS1-TIS2 simulating the vibration leakage signal are input to the detection circuit 140 in the second operation mode. The processing circuit 630 acquires the angular velocity data by changing the phase of the synchronization signal SYC1. For example, the delay time of the phase adjustment circuit 110 can be set by register setting via the interface circuit 170. The processing circuit 630 obtains the phase of the synchronization signal SYC1 that minimizes the signal value of the angular velocity data based on the acquired angular velocity data. The processing circuit 630 writes the setting data PSD1 corresponding to the obtained phase of the synchronization signal SYC1 in the storage unit 180. In this way, an accurate phase of the synchronization signal SYC1 that can reduce the vibration leakage signal in the synchronous detection can be determined.

  For example, since the detection signal includes unnecessary signals such as harmonics in addition to the vibration leakage signal, the phase with the maximum sensitivity is not necessarily 90 degrees with respect to the vibration leakage signal. If the synchronization signal SYC1 is adjusted so as to maximize the sensitivity, the vibration leakage signal cannot always be reduced. Further, the phase of the synchronization signal may be shifted due to process variations, temperature fluctuations, etc., and the accuracy of phase adjustment of the synchronization signal may be reduced. In this regard, according to the present embodiment, the phase of the synchronization signal SYC1 that can reduce the vibration leakage signal in the synchronous detection can be determined by using the phase adjustment method as described above.

  As shown in FIG. 4, the test circuit 130 includes a switch SWT1 provided between the input node NS1 and the first node N1, a switch SWT2 provided between the input node NS2 and the second node N2, including. The test circuit 130 includes a capacitor CT1 provided between the first node N1 and the third node N3, a capacitor CT2 provided between the second node N2 and the third node N3, And a switch SWT3 provided between the node N3 and the test signal input terminal TTI. The test circuit 130 includes a switch SWS1 provided between the input node NS1 and the detection signal input terminal TS1, and a switch SWS2 provided between the input node NS2 and the detection signal input terminal TS2. The switches SWT1 to SWT3 are first to third switches, the switch SWS1 is a fourth switch, and the switch SWS2 is a fifth switch. The capacitor CT1 is a first capacitor, and the capacitor CT2 is a second capacitor.

  The switches SWT1 to SWT3, SWS1, and SWS2 are composed of transistors. For example, these switches are controlled to be turned on or off by a register setting. Further, the capacitance of the capacitor CT2 is different from the capacitance of the capacitor CT1. During the test, the switches SWT1 to SWT3 are turned on and the switches SWS1 and SWS2 are turned off. As a result, the test input signals TIS1 and TIS2 can be input to the detection circuit 140 based on the test signal STE2 input from the test apparatus 600 via the test signal input terminal TTI. On the other hand, during normal operation of the gyro sensor, the switches SWT1 to SWT3 are turned off and the switches SWS1 and SWS2 are turned on. Accordingly, the detection signals S1 and S2 input from the vibrator 10 via the detection signal input terminals TS1 and TS2 can be input to the detection circuit 140.

  As described above, the test signals STE1 and STE2 have a given phase relationship. This given phase relationship is a phase relationship in which the phase difference between the test signals STE1 and STE2 is 90 degrees. Note that the phase of the test signal STE2 may be advanced by 90 degrees with respect to the test signal STE1, or may be delayed by 90 degrees.

  When the phase difference between the test signals STE1 and STE2 is 90 degrees, the phase between the test signal STE1 and the test input signals TIS1-TIS2 is the same or opposite. As described in FIG. 2, the vibration leakage signal is in phase with the feedback signal DG. That is, the test input signals TIS1-TIS2 are signals that simulate the vibration leakage signal. The test apparatus 600 reads out the angular velocity data in a state where the test input signals TIS1-TIS2 are input to the detection circuit 140, and adjusts the phase of the synchronization signal SYC1 so that the signal value of the angular velocity data is minimized. In addition, phase adjustment capable of reducing the vibration leakage signal is possible.

  Note that the test apparatus 600 may acquire an analog angular velocity signal from the circuit device 100 and adjust the phase based on the angular velocity signal. Specifically, the circuit device 100 includes an output terminal TTQ1. The output terminal TTQ1 is a first output terminal. The output terminal TTQ1 outputs the output signal LPQ1 of the low-pass filter 143 in the second operation mode. That is, the output terminal TTQ1 outputs the output signal LPQ1 of the low-pass filter 143 during the test.

  The monitor circuit 620 of the test apparatus 600 monitors the output signal LPQ1 from the output terminal TTQ1. For example, the output signal LPQ1 is A / D converted. The processing circuit 630 adjusts the phase of the synchronization signal SYC1 so that the signal value of the A / D conversion data becomes the minimum value. It is possible to adjust the phase of the synchronization signal SYC1 also by such a method. When the test apparatus 600 acquires angular velocity data via the interface circuit 170, the output terminal TTQ1 may be omitted.

  As shown in FIG. 4, the circuit device 100 includes a storage unit 180 that stores phase adjustment setting data PSD1.

  The test apparatus 600 writes the setting data PSD1 of the phase adjustment circuit 110 that realizes the phase of the adjusted synchronization signal SYC1 in the storage unit 180. Thereby, during the normal operation of the gyro sensor, the phase adjustment circuit 110 can output the synchronization signal SYC1 whose phase is 90 degrees different from the vibration leakage signal based on the setting data PSD1 stored in the storage unit 180.

  As will be described later with reference to FIGS. 5 and 8, the phase adjustment circuit 110 includes a delay circuit that delays the signal from the drive circuit 150, and outputs the synchronization signal SYC1 based on the output signal of the delay circuit. The setting data PSD1 stored in the storage unit 180 is data for setting the delay time of the delay circuit.

  According to the present embodiment, the phase adjustment circuit 110 can generate the synchronization signal SYC1 by delaying the synchronous detection clock SDET1 by the delay circuit. Then, by setting the delay time of the delay circuit based on the setting data PSD1 stored in the storage unit 180, it is possible to obtain the synchronization signal SYC1 whose phase is 90 degrees different from the vibration leakage signal.

  As illustrated in FIG. 4, the circuit device 100 includes a synchronous detection circuit 144 that performs a detection process on the output signal QVQ of the amplifier circuit 141 based on the synchronous signal SYC2 and extracts a vibration leakage signal.

  Thereby, a vibration leakage signal is extracted from the detection signal, and signal processing using the vibration leakage signal can be performed. For example, the signal level of the vibration leakage signal is compared with a threshold, and when the signal level falls below the threshold, it can be determined that an abnormality has occurred in the gyro sensor.

  When adjusting the phase of the synchronization signal SYC2 for detecting the vibration leakage signal, the given phase relationship between the test signals STE1 and STE2 is such that the phase difference between the test signals STE1 and STE2 is 0 degrees or 180 degrees. This is the phase relationship.

  When the phase difference between the test signals STE1 and STE2 is 0 degree or 180 degrees, the phase difference between the test signal STE1 and the test input signals TIS1-TIS2 is different by 90 degrees. As described with reference to FIG. 3, the angular velocity signal is 90 degrees out of phase with the feedback signal DG. That is, the test input signals TIS1-TIS2 are signals simulating an angular velocity signal. With the test input signals TIS1-TIS2 being input to the detection circuit 140, the test apparatus 600 reads the vibration leakage data and adjusts the phase of the synchronization signal SYC2 so that the signal value of the vibration leakage data is minimized. A phase adjustment capable of reducing the angular velocity signal with high accuracy is possible.

  Note that the test apparatus 600 may acquire an analog vibration leakage signal from the circuit device 100 and adjust the phase based on the vibration leakage signal. Specifically, the circuit device 100 includes an output terminal TTQ2. The output terminal TTQ1 is a second output terminal. The output terminal TTQ2 outputs the output signal LPQ2 of the low-pass filter 145 in the second operation mode. That is, the output terminal TTQ2 outputs the output signal LPQ2 of the low-pass filter 145 during the test.

  The monitor circuit 620 of the test apparatus 600 monitors the output signal LPQ2 from the output terminal TTQ2. For example, the output signal LPQ2 is A / D converted. The processing circuit 630 adjusts the phase of the synchronization signal SYC2 so that the signal value of the A / D conversion data becomes the minimum value. It is also possible to adjust the phase of the synchronization signal SYC2 by such a method. Note that when the test apparatus 600 acquires vibration leakage data via the interface circuit 170, the output terminal TTQ2 may be omitted.

2. Phase Adjustment Circuit FIG. 5 is a first detailed configuration example of the phase adjustment circuit. FIG. 5 illustrates the phase adjustment circuit 110 as an example, but the phase adjustment circuit 120 has the same configuration.

  The phase adjustment circuit 110 includes delay circuits DE1 to DEn. n is an integer of 2 or more. Delay circuit DE1 includes a buffer circuit DBF1, and a variable capacitance circuit CDL1 provided between an output node of buffer circuit DBF1 and a ground node. The delay circuits DE2 to DEn have the same configuration. The synchronous detection clock SDET1 is input to the input node of the buffer circuit DBF1. The output signal of the buffer circuit DBF1 is input to the input node of the buffer circuit DBF2. The same applies to the following, and the output signal of the buffer circuit DBFn is output as the synchronization signal SYC1. The capacitances of the variable capacitance circuits CDL1 to CDLn are set by setting data PSD1 stored in the storage unit 180. Thereby, the delay times of the delay circuits DE1 to DEn are set, and the phase of the synchronization signal SYC1 with respect to the synchronous detection clock SDET1 is set.

  During the test, the test apparatus 600 inputs the test signal STE1 to the feedback signal input terminal TDG, inputs the test signal STE2 to the test signal input terminal TTI, and acquires angular velocity data while changing the setting data PSD1. Then, the test apparatus 600 obtains setting data PSD1 that minimizes the signal value of the angular velocity data, and writes the obtained setting data PSD1 in the storage unit 180.

  FIG. 6 is a diagram for explaining the temperature dependence of the phase adjustment. A1 in FIG. 6 is a temperature characteristic having a phase difference of the synchronization signal SYC1 with respect to the feedback signal DG, and A2 is a temperature characteristic having a phase difference of the angular velocity signal with respect to the feedback signal DG. The angular velocity signal here is an angular velocity signal included in the signal QVQ input to the synchronous detection circuit 142.

  In the test, it is assumed that the phase difference between the synchronization signal SYC1 and the angular velocity signal is adjusted to zero at the temperature T0. However, due to the temperature characteristics of the current-voltage conversion circuit 151, the synchronous detection clock generation circuit 153, and the phase adjustment circuit 110, a temperature characteristic occurs in the phase difference of the synchronization signal SYC1 with respect to the feedback signal DG. Further, due to the temperature characteristic of the amplifier circuit 141, a temperature characteristic occurs in the phase difference of the angular velocity signal with respect to the feedback signal DG. When the slopes of these temperature characteristics are different, the difference between the temperature characteristics has a slope of the temperature characteristics as indicated by A3 in FIG. A3 is obtained by subtracting the temperature characteristic of the phase difference of the synchronization signal SYC1 from the temperature characteristic of the phase difference of the angular velocity signal. When there is such a gradient of temperature characteristics, the phase difference between the synchronization signal SYC1 and the angular velocity signal does not become zero at a temperature different from T0. For this reason, the vibration leak signal is mixed with the angular velocity signal after the synchronous detection, and the level of the mixed vibration leak signal varies depending on the temperature.

  In order to detect the angular velocity with high accuracy, it is desirable to reduce the temperature characteristic of the phase difference between the synchronization signal SYC1 and the angular velocity signal. Hereinafter, a method for reducing the temperature characteristic of the phase difference between the synchronization signal SYC1 and the angular velocity signal will be described.

  FIG. 7 is a second detailed configuration example of the phase adjustment circuit 110. The phase adjustment circuit 110 includes delay circuits DGA, DGB, DGC and selectors SELA, SELB, SELC. FIG. 7 illustrates the phase adjustment circuit 110 as an example, but the phase adjustment circuit 120 has the same configuration. That is, the temperature characteristic of the phase difference between the synchronization signal SYC2 and the vibration leakage signal can be reduced by the same method.

  The delay circuit DGA includes buffer circuits BFA1 to BFAp connected in series, and the synchronous detection clock SDET1 is input to the buffer circuit BFA1. p is an integer of 2 or more. The selector SELA selects a signal specified by the setting data PSD1 from the output signals of the buffer circuits BFA1 to BFAp, and outputs the selected signal as the output signal SELAQ. The delay circuit DGB includes buffer circuits BFB1 to BFBq connected in series, and the output signal SELAQ is input to the buffer circuit BFB1. q is an integer of 2 or more. The selector SELB selects a signal specified by the setting data PSD1 from the output signals of the buffer circuits BFB1 to BFBq, and outputs the selected signal as the output signal SELBQ. The delay circuit DGC includes buffer circuits BFC1 to BFCr connected in series, and an output signal SELBQ is input to the buffer circuit BFC1. r is an integer of 2 or more. The selector SELC selects a signal specified by the setting data PSD1 from the output signals of the buffer circuits BFC1 to BFCr, and outputs the selected signal as the synchronization signal SYC1.

  The signal delay time in the buffer circuits BFA1 to BFAp has a negative temperature characteristic, the signal delay time in the buffer circuits BFB1 to BFBq has a flat temperature characteristic, and the signal delay time in the buffer circuits BFC1 to BFCr is positive. Temperature characteristics. The slope of the negative temperature characteristic changes depending on which of the output signals of the buffer circuits BFA1 to BFAp is selected by the selector SELA. The slope of the positive temperature characteristic can be adjusted according to which of the output signals of the buffer circuits BFC1 to BFCr is selected by the selector SELC. The absolute value of the delay time can be adjusted depending on which of the output signals of the buffer circuits BFB1 to BFBq is selected by the selector SELB. By adding the above temperature characteristics, the temperature characteristics of the delay time of the entire phase adjustment circuit 110 can be adjusted.

  FIG. 8 is a diagram for explaining the temperature characteristics of the adjusted delay time. B1 in FIG. 8 is a temperature characteristic of the phase difference of the synchronization signal SYC1 with respect to the synchronous detection clock SDET1, and corresponds to the temperature characteristic of the delay time of the phase adjustment circuit 110 as a whole. The phase difference at the temperature T0 is x. This is the same as the phase difference x of the angular velocity signal input to the synchronous detection circuit 142 with respect to the feedback signal DG, as indicated by A2 in FIG. Further, the inclination of the temperature characteristic B1 cancels the inclination of the temperature characteristic indicated by A3 in FIG. A3 is a temperature characteristic that the phase difference of the synchronization signal SYC1 with respect to the angular velocity signal has. Specifically, the slope of the temperature characteristic B1 in FIG. 8 is such that the slope of the temperature characteristic indicated by A1 in FIG. 6 matches the slope of the temperature characteristic indicated by A2. A1 is a temperature characteristic having a phase difference of the synchronization signal SYC1 with respect to the feedback signal DG, and A2 is a temperature characteristic having a phase difference of the angular velocity signal with respect to the feedback signal DG. As described above, as shown in B2 of FIG. 8, the phase difference of the synchronization signal SYC1 with respect to the angular velocity signal input to the synchronous detection circuit 142 has a flat characteristic with respect to temperature.

3. Phase Adjustment Method A method for adjusting the phase of the synchronization signal SYC1 at the time of testing when the phase adjustment circuit 110 of FIG. 7 is used will be described. FIG. 9 is a flowchart showing the phase adjustment procedure. In the following, the case where the phase of the synchronization signal SYC1 is adjusted will be described as an example.

  As shown in FIG. 9, the temperature is set in step S11. That is, when acquiring data at a plurality of temperatures, one of the plurality of temperatures is set as the environmental temperature of the circuit device 100. Here, it is assumed that the plurality of temperatures are T1, T2, and T3, and T1 is selected first.

  Next, angular velocity data is acquired in step S12. That is, the test apparatus 600 monitors the detection result from the detection circuit 140. Specifically, the test signal generation circuit 610 of the test apparatus 600 inputs the test signal STE1 to the feedback signal input terminal TDG, inputs the test signal STE2 to the test signal input terminal TTI, and the processing circuit 630 receives the angular velocity from the circuit apparatus 100. Read data. At this time, the angular velocity data is acquired by changing the setting data PSD1 of the phase adjustment circuit 110.

  Next, the delay time of the phase adjustment circuit 110 is measured in step S13. As shown in FIG. 4, the second test circuit 160 includes a switch SWI1 provided between the delay test terminal TPI and the input node of the phase adjustment circuit 110, a delay test terminal TPQ, and an output node of the phase adjustment circuit 110. And a switch SWQ1 provided between the two. The second test circuit 160 is provided between the switch SWI2 provided between the delay test terminal TPI and the input node of the phase adjustment circuit 120, and between the delay test terminal TPQ and the output node of the phase adjustment circuit 120. Switch SWQ2. These switches are constituted by transistors. During the normal operation of the gyro sensor, the switches SWI1, SWQ1, SWI2, and SWQ2 are off. During the test, when measuring the delay time of the phase adjustment circuit 110, the switches SWI1 and SWQ1 are on and the switches SWI2 and SWQ2 are off. The delay measurement circuit 640 of the test apparatus 600 inputs a pulse signal to the phase adjustment circuit 110 via the delay test terminal TPI. The delay measurement circuit 640 acquires the output pulse signal of the phase adjustment circuit 110 via the delay test terminal TPQ, and measures the delay time of the phase adjustment circuit 110. At this time, the delay time is measured by changing the setting data PSD1 of the phase adjustment circuit 110. For example, the delay time when the selector SELA in FIG. 7 selects the output signal of the buffer circuit BFA1 and the delay time when the selector SELA selects the output signal of the buffer circuit BFAp are measured. Thereby, the delay time per buffer circuit can be known. A similar method is applied to the selectors SELB and SELC.

  Next, in step S14, it is determined whether all temperatures T1, T2, and T3 have been measured. If there is an unmeasured temperature, the temperature is set in step S11. When all the temperatures are set, the process proceeds to step S15.

  In step S15, the delay time and inclination necessary for phase adjustment are obtained. In step S12, the angular velocity data is acquired by changing the setting data PSD1, and in step S13, the delay time of the phase adjustment circuit 110 is measured by changing the setting data PSD1. Based on these, the angular velocity data at each delay time can be known as shown in FIG. FIG. 10 shows the measurement results at the temperature T1, and the black circles shown in FIG. 10 indicate the measured angular velocity data. Here, measurement is performed at three delay times. Using a fitting process or the like, a delay time DTM1 that minimizes the signal value of the angular velocity data is obtained. This is also performed for the temperatures T2 and T3. The delay times obtained at temperatures T2 and T3 are DTM2 and DTM3. As shown in FIG. 11, the temperature characteristics of the delay time are obtained from the delay times DTM1, DTM2, and DTM3 obtained at the temperatures T1, T2, and T3. For example, the slope of the temperature characteristic is obtained by performing a fitting process with a linear function.

  Next, in step S16, setting data PSD1 is determined. In step S13, the delay time is measured for each of the temperatures T1, T2, and T3 by changing the setting data PSD1. The processing circuit 630 of the test apparatus 600 can obtain the relationship between the setting data PSD1 and the temperature characteristic of the delay time from this measurement result. From this relationship, the processing circuit 630 obtains the setting data PSD1 that realizes the temperature characteristic of the delay time obtained in step S15, and writes the obtained setting data PSD1 in the storage unit 180.

4). FIG. 12 is a configuration example of an electronic device 500 including the circuit device 100. The electronic device 500 includes a physical quantity measuring device 400 including the circuit device 100 and a processing device 520. Further, the communication unit 510, the operation unit 530, the display unit 540, the storage unit 550, and the antenna ANT can be included.

  Various devices can be assumed as the electronic device 500. For example, a wearable device such as a GPS built-in clock, a biological information measuring device, or a head-mounted display device can be assumed. The biological information measuring device is, for example, a pulse wave meter, a pedometer or the like. Alternatively, a portable information terminal such as a smartphone, a mobile phone, a portable game device, a notebook PC, or a tablet PC can be assumed. Alternatively, a content providing terminal for distributing content, a video device such as a digital camera or a video camera, or a network-related device such as a base station or a router can be assumed. Alternatively, a measuring device that measures a physical quantity such as distance, time, flow velocity, or flow rate, an in-vehicle device, a robot, or the like can be assumed. The in-vehicle device is, for example, an automatic driving device.

  The communication unit 510 is a communication circuit, for example, a wireless circuit. The radio circuit performs processing for receiving data from the outside via the antenna ANT and transmitting data to the outside. The processing device 520 performs electronic device control processing, various digital processing of data transmitted and received via the communication unit 510, and the like. The function of the processing device 520 can be realized by a processor such as a microcomputer. The operation unit 530 is a device for a user to perform an input operation, and can be realized by an operation button, a touch panel display, or the like. The display unit 540 is a device that displays various types of information, and can be realized by a display such as a liquid crystal or an organic EL. The storage unit 550 is a device that stores data, and its function can be realized by a semiconductor memory such as a RAM or a ROM, a hard disk drive, or the like.

  FIG. 13 is an example of a moving object including the circuit device 100. The circuit device 100 can be incorporated into various moving bodies such as a car, an airplane, a motorcycle, a bicycle, a robot, or a ship. The moving body is, for example, a device or device that includes a drive mechanism such as an engine or a motor, a steering mechanism such as a handle or a rudder, and various in-vehicle electronic devices, and moves on the ground, the sky, or the sea. FIG. 13 schematically shows an automobile 206 as a specific example of the moving object. A physical quantity measuring device including the circuit device 100 is incorporated in the automobile 206. The control device 208 performs various control processes based on the physical quantity measured by the physical quantity measuring device. For example, when the physical quantity measuring device is a gyro sensor, the gyro sensor can detect the posture of the body 207. The body 207 is a vehicle body in the automobile 206. A detection signal from the gyro sensor is supplied to the control device 208. The control device 208 can control the hardness of the suspension and the brakes of the individual wheels 209 according to the posture of the body 207, for example. The device in which the circuit device 100 is incorporated is not limited to such a control device 208, and can be incorporated in various devices provided in a moving body such as the automobile 206 and a robot.

  Although the present embodiment has been described in detail as described above, it will be easily understood by those skilled in the art that many modifications can be made without departing from the novel matters and effects of the present invention. Accordingly, all such modifications are intended to be included in the scope of the present invention. For example, a term described at least once together with a different term having a broader meaning or the same meaning in the specification or the drawings can be replaced with the different term in any part of the specification or the drawings. All combinations of the present embodiment and the modified examples are also included in the scope of the present invention. Further, the configurations and operations of the circuit device, the physical quantity measuring device, the electronic device, the moving body, the phase adjustment method, and the like are not limited to those described in the present embodiment, and various modifications can be made.

DESCRIPTION OF SYMBOLS 10 ... Vibrator, 100 ... Circuit apparatus, 110 ... Phase adjustment circuit, 120 ... Phase adjustment circuit, 130 ... Test circuit, 140 ... Detection circuit, 141 ... Amplification circuit, 142 ... Synchronous detection circuit, 143 ... Low pass filter, 144 ... Synchronous detection circuit, 145 ... low pass filter, 146 ... multiplexer, 147 ... A / D conversion circuit, 148 ... processing circuit, 150 ... drive circuit, 151 ... current / voltage conversion circuit, 152 ... drive signal generation circuit, 153 ... synchronous detection Clock generation circuit, 154 ... synchronous detection clock generation circuit, 160 ... second test circuit, 170 ... interface circuit, 180 ... storage unit, 206 ... automobile, 207 ... body, 208 ... control device, 209 ... wheel, 400 ... physical quantity measurement Device 500 ... electronic device 510 ... communication unit 520 ... processing device 530 ... operation unit, DESCRIPTION OF SYMBOLS 40 ... Display part, 550 ... Memory | storage part, 600 ... Test apparatus, 610 ... Test signal generation circuit, 620 ... Monitor circuit, 630 ... Processing circuit, 640 ... Delay measurement circuit, DE1-DEn ... Delay circuit, DGA, DGB, DGC ... delay circuit, DG ... feedback signal, DS ... drive signal, NS1, NS2 ... input node, PSD1, PSD2 ... setting data, S1, S2 ... detection signal, SDET1, SDET2 ... synchronous detection clock, STE1, STE2 ... test signal, SWS1, SWS2, SWT1 to SWT3 ... switch, SYC1, SYC2 ... synchronization signal, TDG ... feedback signal input terminal, TDS ... drive signal output terminal, TIS1, TIS2 ... test input signal, TS1, TS2 ... detection signal input terminal, TTI ... Test signal input terminals, TTQ1, TTQ2 ... Output Child

Claims (13)

A drive circuit;
A feedback signal input terminal connected to the drive circuit;
A detection circuit having a first input node, a second input node, and a synchronous detection circuit;
A first detection signal input terminal;
A second detection signal input terminal;
A test signal input terminal;
A test circuit connected to the first input node, the second input node, the first detection signal input terminal, the second detection signal input terminal, and the test signal input terminal;
A phase adjustment circuit;
Including
Switching between the first operation mode and the second operation mode is possible,
In the first operation mode,
The drive circuit outputs a drive signal for driving the physical quantity transducer based on a feedback signal from the physical quantity transducer input to the feedback signal input terminal,
The phase adjustment circuit performs phase adjustment on the signal from the drive circuit based on the feedback signal, and outputs the signal after phase adjustment to the synchronous detection circuit as a synchronization signal,
The test circuit outputs a first detection signal from the physical quantity transducer input to the first detection signal input terminal to the first input node, and input to the second detection signal input terminal. Outputting a second detection signal to the second input node;
The synchronous detection circuit performs detection processing based on the first detection signal and the second detection signal,
The detection circuit detects a physical quantity signal based on an output signal of the synchronous detection circuit,
In the second operation mode,
The phase adjustment circuit adjusts the phase of the signal from the drive circuit based on the first test signal input to the feedback signal input terminal, and uses the signal after phase adjustment as a synchronization signal to the synchronous detection circuit. Output,
The test circuit outputs a first test input signal to the first input node and outputs a second test input signal based on the second test signal input from the test signal input terminal. Output to the second input node,
The second test signal is a signal having a given phase relationship with respect to the first test signal;
The synchronous detection circuit performs detection processing based on the first test input signal and the second test input signal,
The circuit device characterized in that the detection circuit outputs a signal based on an output signal of the synchronous detection circuit. The circuit device according to claim 1,
The test circuit includes:
A first switch provided between the first input node and the first node;
A second switch provided between the second input node and a second node;
A first capacitor provided between the first node and the third node;
A second capacitor provided between the second node and the third node;
A third switch provided between the third node and the test signal input terminal;
A fourth switch provided between the first input node and the first detection signal input terminal;
A fifth switch provided between the second input node and the second detection signal input terminal;
A circuit device comprising: The circuit device according to claim 1 or 2,
The given phase relationship is
A circuit device having a phase relationship in which a phase difference between the first test signal and the second test signal is 90 degrees. The circuit device according to any one of claims 1 to 3,
Including output terminals,
The detection circuit includes:
An amplifier circuit for amplifying signals input to the first input node and the second input node;
A low-pass filter that performs low-pass filter processing on the output signal of the synchronous detection circuit;
Have
The synchronous detection circuit is
Perform detection processing on the output signal of the amplifier circuit,
The output terminal is
In the second operation mode, an output signal of the low-pass filter is output. In the circuit device according to any one of claims 1 to 4,
A circuit device comprising a storage unit for storing setting data of the phase adjustment. The circuit device according to claim 5,
The phase adjustment circuit includes:
A delay circuit that delays a signal from the drive circuit, and outputs the synchronization signal based on an output signal of the delay circuit;
The setting data is
A circuit device comprising data for setting a delay time of the delay circuit. The circuit device according to any one of claims 1 to 3,
A second phase adjustment circuit that outputs a second synchronization signal based on a signal from the drive circuit and adjusts the phase of the second synchronization signal;
The detection circuit includes:
An amplifier circuit for amplifying signals input to the first input node and the second input node;
A first synchronous detection circuit that performs a detection process on the output signal of the amplifier circuit based on the synchronous signal and extracts the physical quantity signal;
A second synchronous detection circuit that performs a detection process on the output signal of the amplifier circuit based on the second synchronous signal and extracts a vibration leakage signal;
A circuit device comprising: The circuit device according to claim 7, wherein
The given phase relationship is
A circuit device characterized in that the phase difference between the first test signal and the second test signal is 0 degree or 180 degrees. The circuit device according to claim 7 or 8,
Including a first output terminal and a second output terminal;
The detection circuit includes:
A first low-pass filter that performs low-pass filter processing on the output signal of the first synchronous detection circuit;
A second low-pass filter that performs low-pass filter processing on the output signal of the second synchronous detection circuit;
Have
The first output terminal is
In the second operation mode, an output signal of the first low-pass filter is output,
The second output terminal is
In the second operation mode, an output signal of the second low-pass filter is output. A circuit device according to any one of claims 1 to 9,
The physical quantity transducer;
A physical quantity measuring device comprising: A circuit device according to any one of claims 1 to 9,
A processing device for performing signal processing based on the physical quantity signal;
An electronic device comprising: A circuit device according to any one of claims 1 to 9,
A body provided with the circuit device;
A moving object comprising: A phase adjustment method for the circuit device according to any one of claims 1 to 9,
Set to the second operation mode during testing,
The first test signal is input to the feedback signal input terminal, and the second test signal is input to the test signal input terminal.
Monitor the detection result from the detection circuit,
A phase adjustment method, wherein the phase adjustment setting data is obtained based on the detection result.

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