Inertial sensor device and sensor module

Abstract

An inertial sensor device and a sensor module that reduce the adjustment burden on the host side are provided. An inertial sensor device (100) includes a first interface (110), a second sensor (102), a second interface (120), a host interface (140), and a processing circuit (130). The first interface (110) is an interface with a first sensor (1) that detects a first physical quantity (P1) on a first detection axis, a second physical quantity (P2) on a second detection axis, and a third physical quantity (P3) on a third detection axis. The second sensor (102) detects the physical quantity (P3) on the third detection axis as a high-precision third physical quantity (HP3) with higher precision than the first sensor. The processing circuit (130) outputs the first physical quantity (P1) and the second physical quantity (P2) to a host (200) via the host interface (140), and outputs the high-precision third physical quantity (HP3) instead of the third physical quantity (P3) to the host (200) via the host interface (140).

Description

Technical Field

[0001] This invention relates to inertial sensor devices and sensor modules, etc. Background Technology

[0002] Patent Document 1 describes a triaxial angular velocity sensor and a triaxial acceleration sensor formed of silicon movable parts on a substrate of a host device.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2016-031358

[0004] When higher precision detection data than these sensors are required, additional sensors need to be added. However, when further connecting additional sensors to the host device, there are issues where adjustments made on the host device side, such as changing the host device's interface specifications, become complicated with the addition of sensors. Summary of the Invention

[0005] One aspect of this disclosure relates to an inertial sensor device, comprising: a first interface, which is an interface with a first sensor, the first sensor detecting a first physical quantity on a first detection axis, a second physical quantity on a second detection axis, and a third physical quantity on a third detection axis; a second sensor, which detects the physical quantity on the third detection axis as a high-precision third physical quantity with a higher precision than the first sensor; a second interface, which is an interface with the second sensor; a host interface, which is an interface with a host computer; and a processing circuit, which outputs the first physical quantity and the second physical quantity to the host computer via the host interface, and outputs the high-precision third physical quantity to the host computer in place of the third physical quantity via the host interface.

[0006] In addition, other aspects of this disclosure relate to a sensor module that includes the aforementioned inertial sensor device and the first sensor. Attached Figure Description

[0007] Figure 1 This is a block diagram illustrating a configuration example of this embodiment.

[0008] Figure 2 This is a diagram illustrating an example of the communication relationship in this embodiment.

[0009] Figure 3 This is a diagram illustrating other configuration examples of this embodiment.

[0010] Figure 4 This diagram illustrates examples of other communication relationships in this embodiment.

[0011] Figure 5This is a diagram illustrating the first detection axis, the second detection axis, and the third detection axis.

[0012] Figure 6 This is a graph illustrating the effect of measurement error on the third physical quantity.

[0013] Figure 7 This is a diagram illustrating an example of data communication in this embodiment.

[0014] Figure 8 This is a diagram illustrating other examples of data communication in this embodiment.

[0015] Figure 9 This is a timeline illustrating the method of this embodiment.

[0016] Figure 10 This is a timeline illustrating other methods of this embodiment.

[0017] Figure 11 This is a timeline illustrating other methods of this embodiment.

[0018] Figure 12 This is a block diagram illustrating a variation of this embodiment.

[0019] Figure 13 This is a diagram illustrating an example of the communication relationship in a variation of this embodiment.

[0020] Figure 14 This is a timeline illustrating the method in a variation of this embodiment.

[0021] Explanation of reference numerals in the attached figures

[0022] 1. First sensor; 100. Inertial sensor device; 102. Second sensor; 110. First interface; 120. Second interface; 130. Processing circuit; 140. Host interface; 150. Inspection interface; 160. Memory; 162. First meter; 164. Second meter; 200. Host; 300. Inspection device; P1. First physical quantity; P2. Second physical quantity; P3. Third physical quantity; HP3. High-precision third physical quantity; BF1. First buffer; BF2. Second buffer; BF3, Third buffer; CS, Signal line (signal); CLK, Signal line (signal); DIN, Signal line (signal); DOUT1, Signal line (signal); DOUT2, Signal line (signal); CSA, Signal line (signal); CLKA, Signal line (signal); DINA, Signal line (signal); DOUTA, Signal line (signal); CSB, Signal line (signal); CLKB, Signal line (signal); DNB, Signal line (signal) DOUTB, signal line (signal); DRDYB, signal line (signal); CS3, signal line (signal); CLK3, signal line (signal); DIN3, signal line (signal); DOUT3, signal line (signal); CS4, signal line (signal); CLK4, signal line (signal); DIN4, signal line (signal); DOUT4, signal line (signal); DRDY4, signal line (signal); RC, read command; G1, first angular velocity; G2, second angular velocity; G3, third angular velocity; HG3, high-precision third angular velocity; A1, first acceleration; A2, second acceleration; A3, third acceleration; CG1, corrected first angular velocity; CG2, corrected second angular velocity; CG3, corrected third angular velocity; CHG3, corrected high-precision third angular velocity; CA1, corrected first acceleration; CA2, corrected second acceleration; CA3, corrected third acceleration; SCL, signal line; SDA, signal line. Detailed Implementation

[0023] The preferred embodiments of this disclosure will now be described in detail. It should be noted that the embodiments described below are not intended to unduly limit the contents of the claims, and not all of the components described in these embodiments are necessarily essential elements.

[0024] Figure 1This is a block diagram illustrating an example configuration of the inertial sensor device 100 according to this embodiment. The inertial sensor device 100 of this embodiment includes a second sensor 102, a first interface 110 serving as an interface with the first sensor 1, a second interface 120, a processing circuit 130, and a host interface 140 serving as an interface with the host 200. The inertial sensor device 100 of this embodiment is configured with a predetermined semiconductor package. Prescribed semiconductor packages include, for example, insert-mount type DIP (Dual In-line Package) or surface-mount type QFP (Quad Flat Package). Furthermore, in the following description, the semiconductor package may sometimes be simply referred to as a package.

[0025] The first sensor 1, for example, detects a physical quantity in the X-axis direction and outputs digital X-axis physical quantity data. X-axis physical quantity data is digital data representing a physical quantity in the X-axis direction. It should be noted that, in the following description, digital data will sometimes be simply referred to as data. Furthermore, the first sensor 1, for example, detects a physical quantity in the Y-axis direction and outputs digital Y-axis physical quantity data, and detects a physical quantity in the Z-axis direction and outputs digital Z-axis physical quantity data. Similarly, Y-axis physical quantity data is digital data representing a physical quantity in the Y-axis direction, and Z-axis physical quantity data is digital data representing a physical quantity in the Z-axis direction. Here, the X-axis and Y-axis are mutually orthogonal axes, becoming axes in directions orthogonal to the Z-axis. That is, the first sensor 1 is a triaxial physical quantity sensor. The physical quantity is, for example, acceleration, but it could also be angular velocity, or other physical quantities. For example, when the physical quantity is acceleration, the first sensor 1 is a triaxial acceleration sensor, which can be implemented, for example, by a Si-MEMS sensor device using an electrostatic capacitive method that can detect acceleration in the X-axis, Y-axis, and Z-axis directions with a single device. It should be noted that the first sensor 1 is not limited to this; it can also be implemented using a frequency-varying crystal accelerometer, a piezoelectric accelerometer, or a thermal accelerometer. Furthermore, for example, when the physical quantity is angular velocity, the first sensor 1 is an angular velocity sensor, which can be implemented using a Si-MEMS sensor device, etc. It should be noted that an angular velocity sensor is also called a gyroscope sensor.

[0026] It should be noted that, although the phrase "in" is omitted... Figure 1 The diagram shows that the first sensor 1 includes: a sensor element for detecting physical quantities along each axis; an analog circuit having an amplifier circuit for amplifying the detection signal from the sensor element; and an A / D conversion circuit for converting the analog signal from the analog circuit into digital data. Furthermore, regarding the following... Figure 2 , Figure 9 , Figure 10Similarly, illustrations of the sensor element, analog circuit, A / D conversion circuit, etc., are omitted for the first sensor 1. The output data of this A / D conversion circuit, or the digital data after temperature correction or other correction processing, is output as X-axis physical quantity data to the first interface 110. It should be noted that the physical quantities in the X-axis, Y-axis, and Z-axis directions can all be detected by a single sensor element, or there can be separate sensor elements for detecting physical quantities in the X-axis, Y-axis, and Z-axis directions.

[0027] It should be noted that in the following descriptions, the detection axis parallel to the X-axis will sometimes be referred to as the first detection axis, the detection axis parallel to the Y-axis as the second detection axis, and the detection axis parallel to the Z-axis as the third detection axis. Additionally, the X-axis physical quantity data output by the first sensor 1 will sometimes be referred to as the first physical quantity P1, the Y-axis physical quantity data as the second physical quantity P2, and the Z-axis physical quantity data as the third physical quantity P3. Similarly, in the examples described later, the X-axis angular velocity data will sometimes be referred to as the first angular velocity G1, the Y-axis angular velocity data as the second angular velocity G2, and the Z-axis angular velocity data as the third angular velocity G3. Likewise, the X-axis acceleration data will sometimes be referred to as the first acceleration A1, the Y-axis acceleration data as the second acceleration A2, and the Z-axis acceleration data as the third acceleration A3. In summary, the first sensor 1 detects the first physical quantity P1 on the first detection axis, the second physical quantity P2 on the second detection axis, and the third physical quantity P3 on the third detection axis.

[0028] The first interface 110 is a circuit that performs interface processing related to the transmission and reception of digital data with the first sensor 1 according to a specified communication method. The specified communication method is, for example, a specified serial communication method, but it can also be a parallel communication method. In addition, the specified serial communication method is synchronous SPI (Serial Peripheral Interface), but it can also be I2C (Inter-Integrated Circuit) or UART (Universal Asynchronous Receiver Transmitter), or a communication method that is modified or altered from some of these communication methods.

[0029] The second sensor 102 is a physical quantity sensor capable of detecting physical quantities with higher precision than the first sensor 1. High precision, for example, refers to high resolution, high signal-to-noise ratio (S / N), or low error. More specifically, being able to detect physical quantities with higher precision than the first sensor 1 means that the smallest unit of the physical quantity that the second sensor 102 can detect is smaller than the smallest unit of the physical quantity that the first sensor 1 can detect. For example, when the signal strength output by the sensor elements of the first sensor 1 and the second sensor 102 is the same, the noise intensity of the second sensor 102 is smaller relative to the signal strength. Or, the error relative to the signal strength output by the sensor element of the second sensor 102 is smaller than the error relative to the signal strength output by the sensor element of the first sensor 1. The second sensor 102, for example, detects physical quantities in the Z-axis direction and outputs a high-precision third physical quantity HP3 as high-precision Z-axis physical quantity data. This high-precision Z-axis physical quantity data can also be digital data. In other words, although detailed illustrations are omitted, the second sensor 102 may include: a sensor element for detecting a physical quantity along the Z-axis; an analog circuit, including an amplifier circuit that amplifies the detection signal from the sensor element; and an A / D conversion circuit that converts the analog signal from the analog circuit into digital data. The resulting high-precision digital data of the third physical quantity HP3, compared to the digital data of the third physical quantity P3 output from the first sensor 1, has lower-order values ​​that are more reliable and are output. When the physical quantity detected by the second sensor 102 is, for example, angular velocity, the second sensor 102 is an angular velocity sensor, such as a resonant frequency-changing crystal angular velocity sensor that detects angular velocity based on the Coriolis force applied to a vibrating object. Furthermore, when the physical quantity detected by the second sensor 102 is, for example, acceleration, the second sensor 102 is an acceleration sensor, such as a frequency-changing crystal accelerometer. In summary, the second sensor 102 detects the physical quantity on the third detection axis as the high-precision third physical quantity HP3 with higher accuracy than the first sensor 1.

[0030] Like the first interface 110, the second interface 120 is a circuit that performs interface processing related to the transmission and reception of digital data with the second sensor 102, following a prescribed communication method. The prescribed communication method is as described above. It should be noted that the communication method followed by the second interface 120 may be the same as or different from the communication method followed by the first interface 110.

[0031] The processing circuit 130 performs processing on various parts of the inertial sensor device 100. For example, the processing circuit 130 performs processing to control the second sensor 102, etc. In other words, when communicating with the second sensor 102, etc., based on digital data, the processing circuit 130 acts as a controller relative to the second sensor 102. The processing circuit 130 is constructed from the following hardware. The hardware includes circuitry for processing digital signals, but may also include circuitry for processing analog signals. For example, the hardware can be constructed from one or more circuit devices and one or more circuit elements mounted on a circuit board. The one or more circuit devices are, for example, an IC (Integrated Circuit), an FPGA (Field-Programmable Gate Array), etc. The one or more circuit elements are, for example, resistors, capacitors, etc. In addition, the processing circuit 130 is implemented by including at least one processor. The processing circuit 130 includes a processor for storing information. Figure 1 The memory (not shown) and the processor that operates based on the information stored in the memory. The information includes, for example, programs and various types of data. The processor includes hardware. The processor can be various types of processors such as CPU (Central Processing Unit), GPU (Graphics Processing Unit), and DSP (Digital Signal Processor). The memory can be a semiconductor memory such as SRAM (Static Random Access Memory) or DRAM (Dynamic Random Access Memory), a register, a magnetic storage device such as HDD (Hard Disk Drive), or an optical storage device such as an optical disc drive. For example, the memory stores commands that can be read by a computer, and the processor executes these commands to perform some or all of the functions of the various parts of the processing circuitry 130 as processing. These commands can be commands that constitute a set of commands for a program, or commands that instruct the processor's hardware circuitry to perform actions.

[0032] The host interface 140 is a circuit that performs interface processing related to sending and receiving data with the host 200 according to a prescribed communication method. The prescribed communication method is as described above. It should be noted that the communication method followed by the host interface 140 may be the same as or different from the communication method followed by the first interface 110 or the second interface 120.

[0033] The host 200 is a device electrically connected to the inertial sensor device 100 and acquires physical quantities output from the inertial sensor device 100. The host 200 includes a processing unit (not shown), which can be implemented using a processor similar to the processing circuit 130 described above. For example, the host 200 is included in a measurement system (not shown) and controls various parts of that measurement system. Based on the physical quantities acquired by the host 200, the measurement system can calculate the position, etc., of a specified object to be measured. The specified object to be measured may be a moving body such as a bicycle, a four-wheeled car, a motorcycle, a tram, an airplane, a ship, or an electronic device such as a personal computer, a smartphone, a tablet terminal, a clock, a car navigation device, or various measuring devices, but there are no particular limitations. For example, the measurement system can calculate the position, etc., of the specified object to be measured by including the host 200, a GPS receiver (not shown), and an antenna for GPS reception. Specifically, the GPS receiver receives signals from GPS satellites via the antenna, and the host 200 detects GPS positioning data indicating the position, speed, and orientation of the specified object to be measured based on the signals received by the GPS receiver. It should be noted that the specified location of the object being measured is latitude, longitude, or altitude, etc. Furthermore, the host computer 200 performs inertial navigation calculations on the physical quantity data acquired from the inertial sensor device 100 to obtain inertial navigation positioning data. The inertial navigation positioning data includes the acceleration data and attitude data of the object being measured. Then, based on the obtained inertial navigation positioning data and GPS positioning data, the host computer 200 calculates the specified location of the object being measured. For example, if the specified object being measured is a four-wheeled vehicle, the host computer 200 calculates the exact location of the vehicle on the ground.

[0034] In this embodiment, such as Figure 1 As shown, the host 200 is electrically connected to both the inertial sensor device 100 and the first sensor 1. Specifically, for example, packages of the first sensor 1 and the inertial sensor device 100 are mounted on the circuit board of the host 200. Thus, the processor constituting the processing unit of the host 200 is electrically connected to the terminals of the first sensor 1 package and the inertial sensor device 100 package via defined signal lines. Therefore, when the host 200 performs serial communication with the first sensor 1 and the inertial sensor device 100 according to a standard such as SPI, the processing unit of the host 200 can become a master controller relative to the first sensor 1 and the inertial sensor device 100. Specifically, as... Figure 2 As shown, the host computer 200 is connected to the first sensor 1 and the inertial sensor device 100 via signal lines CS, CLK, and DIN. Furthermore, the first sensor 1 and the inertial sensor device 100 are connected via signal line DOUT1. Additionally, the inertial sensor device 100 and the host computer 200 are also connected via signal line DOUT2. For example, as... Figure 2 As shown, the host 200 connects the signal line CS to the first sensor 1 and the inertial sensor device 100, and makes the negative logic signal through the signal line CS a low level relative to the desired slave device, thereby enabling the transmission and reception of digital data. At this time, the host 200 can also acquire the desired physical quantity as digital data from the first sensor 1 and the inertial sensor device 100 respectively, but can also... Figure 2 The signal line DOUT1 of the first sensor 1 is then connected to the inertial sensor device 100. Therefore, the host 200 can acquire data solely from the inertial sensor device 100. That is, the host 200 does not distinguish between the first sensor 1 and the inertial sensor device 100 using the logic level of the signal via the signal line CS. Furthermore, the connections of the signal lines CS, CLK, DIN, and DOUT2 on the host 200 side remain unchanged compared to the case where only the inertial sensor device 100 is present. Therefore, the host 200 can acquire the desired physical quantities from both the first sensor 1 and the inertial sensor device 100 through serial communication, as if communicating only with the inertial sensor device 100.

[0035] It should be noted that, for example, the attached figure CS is as follows. Figure 2 That refers to the signal line, but there are cases where the description or illustration shows a signal passing through that signal line. The same applies to the reference numerals CLK, DIN, DOUT1, DOUT2, CSA, CLKA, DINA, DOUTA, CSB, CLKB, DINB, DOUTB, DRDYB, CS3, CLK3, DIN3, DOUT3, CS4, CLK4, DIN4, DOUT4, and DRDY4 described later. Additionally, although in Figure 1 The illustration is omitted, but as shown Figure 2 As shown, the inertial sensor device 100 includes, for example, a first buffer BF1. The first buffer BF1 can be implemented, for example, through a register included in the processing circuit 130 or an output register included in the host interface 140.

[0036] Inertial sensor device 100 passes through Figure 2When such a signal line is connected to the first sensor 1, the first interface 110 of the inertial sensor device 100 receives a first physical quantity P1, a second physical quantity P2, and a third physical quantity P3 as sensor data from the first sensor 1. Simultaneously, the second interface 120 of the inertial sensor device 100 receives a high-precision third physical quantity HP3 as sensor data from the second sensor 102 at approximately the same time. This "same time" includes approximately the same timing. Then, the processing circuit 130 outputs the first physical quantity P1 and the second physical quantity P2 received by the first interface 110 to the host 200 via the host interface 140. On the other hand, the processing circuit 130 does not send the third physical quantity P3 received by the first interface 110 to the host 200, but instead outputs the high-precision third physical quantity HP3 received by the second interface 120 to the host 200 via the host interface 140.

[0037] Such communication can be achieved, for example, by the following method. First sensor 1 transmits first physical quantity P1, second physical quantity P2, and third physical quantity P3 as serial data according to the SPI standard to first interface 110 via signal line DOUT1. Processing circuit 130 transmits the serial data from first sensor 1 to signal line DOUT2 via host interface 140 without serial-to-parallel conversion or the like. However, processing circuit 130 replaces a portion of the third physical quantity P3 in the serial data from first sensor 1 with high-precision third physical quantity HP3 data and transmits it to signal line DOUT2. At this time, processing circuit 130 or host interface 140 converts the high-precision third physical quantity HP3 into SPI standard serial data through serial-to-parallel conversion or the like and transmits it to signal line DOUT2.

[0038] As described above, the inertial sensor device 100 of this embodiment includes a first interface 110, a second sensor 102, a second interface 120 serving as an interface with the second sensor 102, a host interface 140 serving as an interface with the host 200, and a processing circuit 130. The first interface 110 is an interface between the first sensor 1 and the first sensor 1, which detects a first physical quantity P1 on a first detection axis, a second physical quantity P2 on a second detection axis, and a third physical quantity P3 on a third detection axis. The second sensor 102 detects the physical quantity on the third detection axis with higher accuracy than the first sensor, as a high-precision third physical quantity HP3. The processing circuit 130 outputs the first physical quantity P1 and the second physical quantity P2 to the host 200 via the host interface 140, and replaces the third physical quantity P3 with the high-precision third physical quantity HP3 and outputs it to the host 200 via the host interface 140.

[0039] Thus, the inertial sensor device 100 of this embodiment, by including a first interface 110 and a second interface 120, can acquire a first physical quantity P1, a second physical quantity P2, and a third physical quantity P3 from the first sensor 1, and acquire a high-precision third physical quantity HP3 from the second sensor 102. Furthermore, the inertial sensor device 100 of this embodiment, by including a processing circuit 130, can output the first physical quantity P1 and the second physical quantity P2 acquired from the first sensor 1, and the high-precision third physical quantity HP3 acquired from the second sensor 102 to the host 200 via the host interface 140. When the accuracy requirement of the physical quantity on the third detection axis is higher than that on the first and second detection axes, in conventional methods, in order for the host 200 to acquire the high-precision third physical quantity HP3, an interface connected to the second sensor 102 needs to be provided on the host 200 side, and adjustments such as replacing sensor data need to be made. Regarding this, by applying the method of this embodiment, the host 200 can acquire the high-precision third physical quantity HP3, replacing the third physical quantity P3, without changing the specifications on the host 200 side. It should be noted that although the example of obtaining a high-precision third physical quantity HP3 for the third detection axis as the Z-axis was described above, the method of this embodiment can also be applied to the first physical quantity P1 for the first detection axis as the X-axis or the second physical quantity P2 for the second detection axis as the Y-axis. In other words, by applying the method of this embodiment, the host 200 can obtain a physical quantity of any axis as a high-precision physical quantity without changing the specifications on the host 200 side.

[0040] Alternatively, the method of this embodiment can also be implemented as a sensor module. That is, the sensor module of this embodiment includes an inertial sensor device 100 and a first sensor 1. In this way, the same effect as described above can be obtained.

[0041] Specifically, for example, the sensor module of this embodiment can be realized by mounting the inertial sensor device 100 and the first sensor 1 on a substrate and packaging them as a semiconductor package. As a result, the number of components installed in the host 200 can be reduced.

[0042] It should be noted that the method of this embodiment is not limited to the above and various modifications can be implemented. For example, although in Figure 1 as well as Figure 2 In this example, the host 200 is electrically connected to the first sensor 1, but as Figure 3 As shown in the block diagram, the host 200 may also not be electrically connected to the first sensor 1. In this case, as... Figure 4As shown, the first sensor 1 and the inertial sensor device 100 are connected via signal lines CSA, CLKA, DINA, and DOUTA, and the processing circuit 130 of the inertial sensor device 100 becomes the main device relative to the first sensor 1. Furthermore, the host computer 200 and the inertial sensor device 100 are connected via signal lines CSB, CLKB, DINA, and DOUTB, and the host computer 200 becomes the main device relative to the processing circuit 130 of the inertial sensor device 100. Additionally, although in Figure 4 The illustrations are omitted, but the inertial sensor device 100 includes, in addition to the components shown above... Figure 2 In addition to the first buffer BF1 described herein, a second buffer BF2 is also included. The second buffer BF2, like the first buffer BF1, can be implemented using the processing circuit 130 or the registers of the host interface 140, etc. Furthermore, as... Figure 4 As shown, the host 200 can also be connected to the inertial sensor device 100 and the DRDYB signal line. Even so, the same effect as described above can be obtained. It should be noted that the number of terminals required for the packaging of the inertial sensor device 100 is... Figure 1 Examples and Figure 3 The examples are different. Thus, since the method of this embodiment can be implemented with multiple configurations of different specifications, the design freedom of the package of the substrate mounted on the host 200 is increased. For example, if it is desirable to minimize the package size of the inertial sensor device 100, it can be configured as follows: Figure 1 The composition example is advantageous in design.

[0043] Here, use Figure 5 and Figure 6 An example will be given where the required accuracy of the physical quantity on the third detection axis is higher than that on the first and second detection axes. As described above, the host unit 200, including the first sensor 1 and the inertial sensor device 100, is included in the measurement system. This measurement system is fixedly mounted on the aforementioned moving body. Figure 5This diagram illustrates the relationship between the direction of movement of a four-wheeled vehicle, an example of the aforementioned moving body, and the coordinate systems of the first sensor 1 and the second sensor 102 included in the measurement system. Hereinafter, the coordinate systems of the first sensor 1 and the second sensor 102 will be simply referred to as the sensor coordinate system. Furthermore, it is assumed that the X-axis, Y-axis, and Z-axis of the coordinate system of the first sensor 1 and the second sensor 102 are aligned. The X-axis of the sensor coordinate system is defined as the forward / backward direction of the moving body, and the forward direction is defined as the positive X-axis. The Y-axis of the sensor coordinate system is defined as the left / right direction of the moving body, and the rightward direction is defined as the positive Y-axis. The Z-axis of the sensor coordinate system is defined as the direction orthogonal to the X-axis and Y-axis, and the downward direction of the moving body is defined as the positive Z-axis. Since the moving body moves on a roughly horizontal plane, the XY plane becomes the moving surface of the moving body, and the positive Z-axis is considered to be aligned with the direction of gravity. Furthermore, the posture of the moving body is expressed by the roll angle about the X-axis, the pitch angle about the Y-axis, and the yaw angle about the Z-axis. Furthermore, as mentioned above, since the moving body moves on a roughly horizontal plane, the roll angle, as an attitude, corresponds to the body's tilt in the left-right direction, the pitch angle corresponds to the body's tilt in the forward-backward direction, and the yaw angle corresponds to the change in the moving body's direction of movement or orientation. In inertial navigation calculations, attitude is calculated by integrating the angular velocity, which is the output signal of the first sensor 1, etc., over time. That is, in Figure 5 In the case where the first sensor 1 and the second sensor 102 are angular velocity sensors, the roll angle is obtained by integrating the first angular velocity G1 acquired by the measurement system over time, the pitch angle is obtained by integrating the second angular velocity G2 over time, and the yaw angle is obtained by integrating the third angular velocity G3 or the high-precision third angular velocity HG3 over time.

[0044] Figure 6 This is a diagram illustrating the positional error. Figure 6The diagram shows the moving body viewed from above, i.e., the XY plane view in the sensor coordinate system. The actual direction of movement is set as the original direction of movement and represented by a solid line. Since the forward direction of the moving body is the positive X-axis direction, the actual direction of movement is also the positive X-axis direction. Assume that the position shown in B1 is the position of the moving body at the first time t1, which is known. The position shown in B2 is the actual position of the moving body at the second time t2, and the position shown in B3 is the position calculated using the inertial navigation calculation of the measurement system, set as the position of the moving body at the second time t2. The distance between the positions shown in B2 and B3 is the position error caused by the offset error of the output signal of the first sensor 1 during the period when the moving body moves from the first time t1 to the second time t2. As mentioned above, since the moving body moves on a roughly horizontal plane, this positional deviation is caused by the error of the yaw angle as an attitude. Furthermore, this yaw angle error increases over time. Therefore, the error in the yaw angle should ideally be smaller than the errors in the roll and pitch angles; in other words, the accuracy of the angular velocity measurement about the Z-axis should ideally be higher than the accuracy of the angular velocity measurement about the X-axis and the angular velocity measurement about the Y-axis. In this regard, by applying the method of this embodiment, the measurement system can obtain a yaw angle based on a high-precision third physical quantity HP3 that replaces the third physical quantity P3 with higher accuracy than the third physical quantity P3 itself. This allows for more accurate prediction of the position of moving objects, etc.

[0045] In summary, in the inertial sensor device 100 of this embodiment, the third physical quantity P3 and the high-precision third physical quantity HP3 are the angular velocities about the third detection axis, which is the Z-axis. In this way, the host 200 can acquire the high-precision third angular velocity HG3 without changing the specifications on the host 200 side.

[0046] Next, use Figure 7 , Figure 8 , Figure 9 , Figure 10 The specific method of the inertial sensor device 100 outputting a first physical quantity P1 and a second physical quantity P2 to the host 200, and replacing the third physical quantity P3 with a high-precision third physical quantity HP3 and outputting it to the host 200, is explained. Figure 7This diagram illustrates a basic example of the communication method used in this embodiment, such as when the host 200, acting as the master device, communicates with a specified physical quantity sensor as a slave device. It should be noted that in the following description, the data transmission and reception of the host 200's communication interface (not shown) will be simply described as the host 200 transmitting and receiving data, etc. First, the host 200, acting as the master device, sets the negative logic signal CS to level L. This causes the specified physical quantity sensor to be chip-selected. Chip selection is also called slave selection. Then, the host 200, acting as the master device, transmits an 8-bit read command RC to the specified physical quantity sensor via signal line DIN, synchronized with the clock of the signal CLK. That is, the clock of the signal CLK here is based on an oscillation circuit (not shown) of the host 200. The read command RC here, for example, has the first bit containing a read / write indication bit, and the host 200 sets the value of this bit to indicate a read. Then, the specified physical quantity sensor transmits 8 bits of sensor data to the host via signal line DOUT2, synchronized with the clock signal of signal line CLK. It should be noted that... Figure 7 The asterisk (*) indicates that it is irrelevant (don't care). Figure 8 The same applies to subsequent diagrams. Additionally, the explanation of synchronization with the clock from the CLK signal will sometimes be omitted below. Furthermore, in... Figure 8 The clock symbol for signal CLK will be omitted from the following diagrams. The same applies to signals CLKA, CLKB, CLK3, and CLK4, which will be discussed later.

[0047] Thus, for example, if a specified physical quantity sensor only detects a physical quantity in one axial direction, three specified physical quantity sensors are prepared, and their respective detection axes are set as the first detection axis, second detection axis, and third detection axis described above. This allows the host 200 to acquire the first physical quantity P1, the second physical quantity P2, and the third physical quantity P3. However, the method of this embodiment is not limited to this. For example, when a master device sends a read command RC to a slave device, the master device can also read multiple data from the slave device. This function is called a burst read function. Figure 8 This is an example where the host device 200, acting as the master device, communicates with a specified triaxial physical quantity sensor as a slave device. By applying the aforementioned burst read function, such as... Figure 8 As shown, when the host 200, as the main device, sends a read command RC to the specified three-axis physical quantity sensor, it can read the physical quantities corresponding to the first physical quantity P1, the second physical quantity P2, and the third physical quantity P3 from the specified three-axis physical quantity sensor.

[0048] Figure 9This diagram illustrates an example of how the host computer 200 acquires a high-precision time map of a third physical quantity, HP3, etc., by applying the method of this embodiment. It is assumed that the first sensor 1, the inertial sensor device 100, and the host computer 200... Figure 2 The signal line connections are shown. Furthermore, it is assumed that the second interface 120 of the inertial sensor device 100 periodically samples the high-precision third physical quantity HP3 from the second sensor 102. Additionally, in this embodiment, it is assumed that there are no issues related to the timing of data transmission and reception in the first sensor 1, the inertial sensor device 100, the host computer 200, etc.

[0049] The host 200 selects both the first sensor 1 and the inertial sensor device 100 by setting the signal CS to L level, and sends a read command RC via signal line DIN to the communication interface of the first sensor 1 and the host interface 140 of the inertial sensor device 100. As shown in C1, the processing circuit 130 of the inertial sensor device 100 stores the high-precision digital data of the third physical quantity HP3 in the first buffer BF1. Furthermore, when the first sensor 1 receives the read command RC from the host 200, it sends the first physical quantity P1, the second physical quantity P2, and the third physical quantity P3 via signal line DOUT1 to the first interface 110 of the inertial sensor device 100. In other words, by setting a predetermined address after the second bit of the read command RC sent by the host 200, the first sensor 1 can send the first physical quantity P1, the second physical quantity P2, and the third physical quantity P3, and the processing circuit 130 can store the high-precision third physical quantity HP3 in the first buffer BF1.

[0050] Then, as shown in C2, the processing circuit 130 transmits the first physical quantity P1 and the second physical quantity P2 received via the first interface 110 to the host 200 as is via the host interface 140 and the signal line DOUT2. Additionally, as shown in C3, when transmitting the third physical quantity P3, the processing circuit 130 replaces the third physical quantity P3 with a high-precision third physical quantity HP3 stored in the first buffer BF1, and transmits it to the host 200 via the host interface 140 and the signal line DOUT2. In this way, the host 200 can receive the high-precision third physical quantity HP3 that replaces the third physical quantity P3.

[0051] It should be noted that the above description uses a triaxial sensor as the first sensor 1, but the method of this embodiment is not limited to this and various modifications can be implemented. For example, the first sensor 1 can also be a six-axis sensor. A six-axis sensor is, for example, a sensor obtained by combining a triaxial physical quantity sensor capable of independently detecting physical quantities in the X-axis, Y-axis, and Z-axis directions, and a triaxial physical quantity sensor capable of independently detecting other physical quantities in the X-axis, Y-axis, and Z-axis directions. For example, in the case where the first sensor 1 is a sensor obtained by combining a triaxial acceleration sensor and a triaxial angular velocity sensor, the first sensor 1 detects a first angular velocity G1, a second angular velocity G2, a third angular velocity G3, a first acceleration A1, a second acceleration A2, and a third acceleration A3. Then, as described above... Figure 5 and Figure 6 As described above, when it is desired that the angular velocity in the Z direction be more accurate than the third angular velocity G3, the inertial sensor device 100 sets the second sensor 102 as the angular velocity sensor for the Z-axis to obtain the high-precision third angular velocity HG3. Then, by applying the above method, as... Figure 10 As shown, the host interface 140 can send the first angular velocity G1, the second angular velocity G2, the high-precision third angular velocity HG3, the first acceleration A1, the second acceleration A2, and the third acceleration A3 to the host 200. It should be noted that the sensor unit composed of the acceleration sensor and the angular velocity sensor is sometimes called an IMU (Inertial Measurement Unit).

[0052] It should be pointed out that, based on Figure 3 as well as Figure 4 In the case shown, for example, according to Figure 11As shown in the timeline, the host 200 is able to acquire high-precision third physical quantities such as HP3. The processing circuit 130 of the inertial sensor device 100 becomes the main device relative to the first sensor 1, setting the signal CSA to L level. Furthermore, the processing circuit 130 stores the high-precision third angular velocity HG3 acquired from the second sensor 102 in the first buffer BF1. Additionally, the inertial sensor device 100 synchronously sends a read command RC to the first sensor 1 via signal line DINA, along with signal CLKA, and reads the first angular velocity G1, second angular velocity G2, third angular velocity G3, first acceleration A1, second acceleration A2, and third acceleration A3 from the first sensor 1 via signal line DOUTA. Then, the processing circuit 130 stores the read first angular velocity G1, second angular velocity G2, first acceleration A1, second acceleration A2, third acceleration A3, and the high-precision third angular velocity HG3 stored in the first buffer BF1 in the second buffer BF2. Additionally, at this time, the processing circuit 130 sets the signal DRDYB to H level, notifying the host 200 that data can be sent. Then, the host 200 becomes the master device relative to the inertial sensor device 100, sets the signal CSB to L level, and synchronously sends a read command RC to the host interface 140 via the signal line DINB, in sync with the signal CLKB. Then, the host 200 reads the first angular velocity G1, the second angular velocity G2, the high-precision third angular velocity HG3, the first acceleration A1, the second acceleration A2, and the third acceleration A3 via the signal line DOUTB.

[0053] Furthermore, although the above description is an example of the inertial sensor device 100 of this embodiment outputting a high-precision third angular velocity HG3 instead of the third angular velocity G3 to the host 200, the method of this embodiment is not limited to this. For example, the inertial sensor device 100 may also output a high-precision third acceleration HA3 instead of the third acceleration A3 to the host 200. That is, in the inertial sensor device 100 of this embodiment, the third physical quantity P3 and the high-precision third physical quantity HP3 are the accelerations about the third detection axis, which is the Z-axis. In this way, when a higher precision is required for the acceleration of a specified axis compared to the accelerations of other axes, the host 200 can obtain the high-precision third acceleration HA3 without changing the specifications on the host 200 side. It should be noted that the case where a higher precision is required for the acceleration of a specified axis compared to the accelerations of other axes is, for example, when the position of an object including a linear motion mechanism requires accurate measurement and control, specifically a linear motor traction train, etc.

[0054] It should be noted that while miniaturization can be achieved when using the aforementioned Si-MEMS inertial sensors to construct a six-axis sensor, it cannot meet the requirements mentioned above. Figure 5The sensor data requires the precision described in the previous section. On the other hand, while high-precision sensor data can be obtained by configuring the first sensor 1 to acquire the six physical quantities using only the aforementioned crystal inertial sensor, miniaturization is not possible. Therefore, in this embodiment, the first sensor 1 can be configured as a small six-axis sensor using a Si-MEMS inertial sensor, and the second sensor 102 can be configured as a crystal inertial sensor to acquire physical quantities only for the direction requiring high precision. In summary, in the inertial sensor device 100 of this embodiment, the first sensor 1 is a MEMS inertial sensor, and the second sensor 102 is a crystal inertial sensor. In this way, a physical quantity sensor that balances miniaturization and high precision can be achieved.

[0055] It should be noted that the method of this embodiment is not limited to the above and various modifications can be implemented. For example, as a modification, the inertial sensor device 100 of this embodiment can also adopt... Figure 12 It has a structure like a block diagram. Figure 12 The example shown is similar to Figure 1 as well as Figure 3 The difference between this example and the previous one is that the inertial sensor device 100 also includes an inspection interface 150 and a memory 160 that can be connected to the inspection device 300. It should be noted that other reference numerals are... Figure 1 as well as Figure 3 It is the same, therefore detailed explanation is omitted.

[0056] In addition, Figure 12 In variations, the relationship between the connected signal lines can also be as follows: Figure 13 As shown. Specifically, the inertial sensor device 100 is connected to the first sensor via signal lines CS3, CLK3, DIN3, and DOUT3. Additionally, the inertial sensor device 100 is connected to the main unit 200 via signal lines CS4, CLK4, DIN4, DOUT4, and DRDY4. Furthermore, the inertial sensor device 100 is connected to the inspection device 300 via signal lines SCL and SDA. Furthermore, although in Figure 12 The illustrations are omitted, but the inertial sensor device 100 includes, in addition to the features mentioned above... Figure 2 and Figure 4 The first buffer BF1 mentioned above, in front of it Figure 4 In addition to the second buffer BF2 described herein, a third buffer BF3 is also included. The third buffer BF3, like the first buffer BF1 and the second buffer BF2, can be implemented through the processing circuit 130 or the registers of the host interface 140, etc.

[0057] In addition, such as Figure 12As shown, the memory 160 also includes a first table 162 and a second table 164. The first table 162 is, for example, a table storing zero-point correction coefficients. Specifically, for a specified temperature range, zero-point data is calculated at each fixed temperature, and the calculated data set is plotted, thereby enabling the calculation of a temperature-related function approximating an nth-degree polynomial as a correction function. The n+1 coefficients of degrees n to 0 in this nth-degree polynomial are the zero-point correction coefficients. Based on these coefficients, without any physical action acting on the first sensor 1 and the second sensor 102, within the aforementioned specified temperature range, the first sensor 1 and the second sensor 102 output signals indicating that the physical quantity is zero.

[0058] Additionally, Table 164 in the second table stores misalignment correction coefficients related to misalignment correction. Misalignment is also known as installation error. For example, as mentioned earlier... Figure 5 In the measurement system described above, due to the mounting error of the first sensor 1 relative to the substrate of the host 200, the directions of the X-axis, Y-axis, and Z-axis of the moving body may sometimes not accurately match the directions of the first detection axis, second detection axis, and third detection axis in the first sensor 1. Therefore, considering the misalignment, a matrix as shown in equation (1) is used, for example, to correct the first physical quantity P1 output by the first sensor 1. That is, the misalignment correction coefficient is composed of the components M11, M12, M13, M21, M22, M23, M31, M32, and M33 of the matrix shown in equation (1). It should be noted that the method for obtaining the misalignment correction coefficient is well-known, and detailed explanation is omitted.

[0059] [Mathematical Expression 1]

[0060]

[0061] PA1: The first physical quantity after misalignment correction

[0062] PA2: The second physical quantity after misalignment correction

[0063] PA3: The third physical quantity after misalignment correction

[0064] PB1: The first physical quantity before alignment correction

[0065] PB2: The second physical quantity before alignment correction

[0066] PB3: The third physical quantity before alignment correction

[0067] The memory 160 is, for example, a non-volatile memory, which can be implemented using EEPROM (Electrically Erasable Programmable Read Only Memory) or flash memory. It should be noted that EEPROM can be implemented using, for example, floating-gate type memory cells. Furthermore, flash memory can be implemented using, for example, MONOS (Metal Oxide Nitride Oxide Silicon) memory cells.

[0068] The inspection interface 150 is a circuit that performs interface processing related to sending and receiving digital data with the inspection device 300 according to a specific communication method. The specific communication method is, for example, I2C, but it can also be other communication standards or modified or altered versions of these standards. The inspection device 300 is a device that writes zero-point correction coefficients or misalignment correction coefficients, etc., into the memory 160. It should be noted that the inertial sensor device 100 preferably has dedicated terminals for connecting to the inspection device 300 by assigning terminals to the terminals of its package, so that it can communicate independently with the inspection device 300 after being mounted on the substrate of the host 200. It should be noted that by setting the specific communication method to I2C, such as... Figure 13 As shown, the inspection interface 150 can communicate with the inspection device 300 via two signal lines consisting of signal line SCL and signal line SDA, thus minimizing the number of dedicated terminals. This reduces the number of terminals in the inertial sensor device 100 package, thereby avoiding unnecessary increases in package size.

[0069] In the case of the inertial sensor device 100 being, for example, the surface-mount type package described above, after the inertial sensor device 100 is aligned with the desired position on the substrate of the host 200, the inertial sensor device 100 and the host 200 are firmly bonded together by soft soldering in a reflow oven, thus achieving surface mounting. It is an empirically known fact that the characteristics of the sensor device change after being surface-mounted onto the desired substrate in this way. For example, although not illustrated, it is an empirically known fact that the position of the zero-point voltage at a specified temperature and the temperature dependence of the zero-point voltage differ before and after surface mounting. It should be noted that, as a reason for the change in the characteristics of the sensor device after surface mounting, considerations include the generation of minute currents due to the excitation of holes or charge carriers in the piezoelectric thin film layer or electrode layer of the sensor element, or the deformation caused by changes in the in-plane stress distribution of the substrate, etc.

[0070] Based on the above reasons, the zero-point value or temperature dependence of the inertial sensor device 100 may change after it is surface-mounted to the host. Therefore, the user can also calculate the aforementioned correction function after surface mounting and store the coefficients of the polynomial of this correction function in the memory 160. Then, before sending the first physical quantity P1, the second physical quantity P2, and the high-precision third physical quantity HP3 from the host interface 140 to the host, the processing circuit 130 performs calculations based on this correction function. As a result, the host interface 140 can output the corrected first physical quantity CP1, the corrected second physical quantity CP2, and the corrected high-precision third physical quantity HP3 to the host 200. In other words, the processing circuit 130 performs zero-point correction on the first physical quantity P1, the second physical quantity P2, and the high-precision third physical quantity HP3, and the host interface 140 outputs the corrected first physical quantity CP1, the second physical quantity CP2, and the high-precision third physical quantity HP3 to the host 200. In this way, it is possible to correct the zero point that has changed due to thermal effects, etc. Therefore, after the inertial sensor device 100 is mounted on the substrate of the host 200, the host 200 can also acquire the corrected first physical quantity CP1, the second physical quantity CP2, and the high-precision third physical quantity CHP3 as appropriate data.

[0071] Furthermore, as described above, after the inertial sensor device 100 is mounted on the host, the orientation of each detection axis of the first sensor 1 or the second sensor 102 may change due to substrate deformation, etc. Therefore, the user can calculate the aforementioned misalignment correction coefficient and store it in the memory 160. Thus, before sending the first physical quantity P1, the second physical quantity P2, and the high-precision third physical quantity HP3 from the host interface 140 to the host, the processing circuit 130 performs the calculation based on the above formula (1). As a result, the host interface 140 can output the corrected first physical quantity CP1, the corrected second physical quantity CP2, and the corrected high-precision third physical quantity CHP3 to the host 200. In other words, the processing circuit 130 performs alignment correction for the detection axes of the first physical quantity P1, the second physical quantity P2, and the high-precision third physical quantity HP3, and the host interface 140 outputs the first physical quantity CP1, the second physical quantity CP2, and the high-precision third physical quantity CHP3 corrected by the alignment correction to the host 200. In this way, the alignment between the detection axes that has changed due to thermal effects, etc., can be corrected. Therefore, after the inertial sensor device 100 is mounted on the substrate of the host 200, the host 200 can also acquire the corrected first physical quantity CP1, the second physical quantity CP2, and the high-precision third physical quantity CHP3 as appropriate data. It should be noted that the processing circuit 130 can also perform this misalignment correction and the aforementioned zero-point correction simultaneously.

[0072] Figure 14 This is an example diagram illustrating the timeline in a modified method. It should be noted that... Figure 14 In this description, some details that are the same as those described previously are omitted. The processing circuit 130 of the inertial sensor device 100 becomes the master device relative to the first sensor 1, and sets the signal CS3 to L level. Furthermore, the processing circuit 130 stores the high-precision third angular velocity HG3 obtained from the second sensor 102 in the first buffer BF1. Additionally, the inertial sensor device 100 sends a read command RC to the first sensor 1 via signal line DIN3, and reads the first angular velocity G1, second angular velocity G2, third angular velocity G3, first acceleration A1, second acceleration A2, and third acceleration A3 from the first sensor 1 via signal line DOUT3. That is, although the diagram is omitted, the clock of signal CLK3 is based on an oscillation circuit (not shown) of the inertial sensor device 100, which is the master device.

[0073] Then, the processing circuit 130 stores the read first angular velocity G1, second angular velocity G2, first acceleration A1, second acceleration A2, third acceleration A3, and high-precision third angular velocity HG3 stored in the first buffer BF1 in the second buffer BF2.

[0074] Subsequently, the processing circuit 130 performs the aforementioned zero-point correction and other correction processes on the first angular velocity G1, the second angular velocity G2, the first acceleration A1, the second acceleration A2, the third acceleration A3, and the high-precision third angular velocity HG3 stored in the second buffer BF2. This operation requires... Figure 14 The period indicated by D.

[0075] Once the calibration process is complete, the processing circuit 130 stores the calibrated first angular velocity CG1, calibrated second angular velocity CG2, calibrated high-precision third angular velocity CHG3, calibrated first acceleration CA1, calibrated second acceleration CA2, and calibrated third acceleration CA3 in the third buffer BF3. Additionally, at this time, the processing circuit 130 sets the signal DRDY4 to H level, notifying the host 200 that the calibrated data can be sent.

[0076] Subsequently, the host device 200 becomes the master device relative to the inertial sensor device 100, sets signal CS4 to L level, and synchronously sends a read command RC to the host interface 140 of the inertial sensor device 100 via signal line DIN4, in sync with signal CLK4. Then, the host device 200 reads the corrected first angular velocity CG1, corrected second angular velocity CG2, corrected high-precision third angular velocity CHG3, corrected first acceleration CA1, corrected second acceleration CA2, and corrected third acceleration CA3 via signal line DOUT4. In this way, the host device 200 can acquire the corrected sensor data. It should be noted that... Figure 14 The example of the time graph shown is similar to Figure 9 and Figure 11 The reason why the examples of time charts are different is that... Figure 14 The period shown in D is longer than the period of the response to the read command RC sent from host 200.

[0077] As explained above, the inertial sensor device of this embodiment includes a first interface, a second sensor, a second interface serving as an interface with the second sensor, a host interface serving as an interface with a host computer, and a processing circuit. The first interface is an interface with the first sensor that detects a first physical quantity on a first detection axis, a second physical quantity on a second detection axis, and a third physical quantity on a third detection axis. The second sensor detects the physical quantity on the third detection axis as a high-precision third physical quantity with higher accuracy than the first sensor. The processing circuit outputs the first and second physical quantities to the host computer via the host interface, and replaces the third physical quantity with the high-precision third physical quantity by outputting it to the host computer via the host interface.

[0078] In this way, the inertial sensor device of this embodiment can output the first and second physical quantities obtained from the first sensor and the high-precision third physical quantity obtained from the second sensor to the host via the host interface. Thus, the host can obtain the high-precision third physical quantity that replaces the third physical quantity without changing the specifications on the host side.

[0079] In addition, the third physical quantity, and the high-precision third physical quantity, can also be the angular velocity around the third detection axis.

[0080] In this way, the host can obtain a high-precision third angular velocity without changing the specifications on the host side.

[0081] In addition, the third physical quantity, and the high-precision third physical quantity, can also be the acceleration on the third detection axis.

[0082] In this way, when the acceleration of a specified axis is required to be more precise than that of other axes, the host machine can obtain a high-precision third acceleration without changing the specifications on the host side.

[0083] Alternatively, the processing circuit can perform zero-point calibration on the first physical quantity, the second physical quantity, and the high-precision third physical quantity, and the host interface can output the first physical quantity, the second physical quantity, and the high-precision third physical quantity after zero-point calibration to the host.

[0084] In this way, the zero point that has changed due to thermal effects can be corrected. Therefore, after the inertial sensor device is mounted on the substrate of the host computer, the host computer can also acquire the first physical quantity, the second physical quantity, and the high-precision third physical quantity after proper correction.

[0085] Alternatively, the processing circuit may perform alignment correction between the detection axes on the first physical quantity, the second physical quantity, and the high-precision third physical quantity, and the host interface may output the first physical quantity, the second physical quantity, and the high-precision third physical quantity corrected by the alignment correction to the host.

[0086] This allows for the correction of alignment issues between detection axes caused by thermal effects. Consequently, after the inertial sensor device is surface-mounted onto the host computer, the host computer can acquire the properly corrected first physical quantity, second physical quantity, and high-precision third physical quantity.

[0087] Alternatively, the first sensor could be a MEMS inertial sensor, and the second sensor could be a crystal inertial sensor.

[0088] This allows for the creation of physical quantity sensors that balance miniaturization and high precision.

[0089] Furthermore, the sensor module of this embodiment relates to a sensor module including the above-described inertial sensor device and the first sensor.

[0090] It should be noted that while this embodiment has been described in detail above, those skilled in the art should readily understand that various modifications can be made without substantially departing from the new aspects and effects of this disclosure. Therefore, all such modifications are included within the scope of this disclosure. For example, in the specification or drawings, a term described at least once with a different term that is more general or synonymous can be replaced with that different term anywhere in the specification or drawings. Furthermore, all combinations of this embodiment and its modifications are also included within the scope of this disclosure. Additionally, the configuration and operation of the inertial sensor device or sensor module are not limited to those described in this embodiment, and various modifications can be implemented.

Claims

1. An inertial sensor device, characterized in that, include: The first interface is the interface between the first sensor and the first sensor, which detects a triaxial physical quantity including a first physical quantity on a first detection axis, a second physical quantity on a second detection axis, and a third physical quantity on a third detection axis. The second sensor detects the physical quantity on the third detection axis as a high-precision third physical quantity with a higher accuracy than the first sensor. The second interface is the interface between the second sensor and the second sensor. The host interface is the interface between the host and the host. Processing circuitry; as well as A semiconductor package housing the first interface, the second sensor, the second interface, the host interface, and the processing circuitry. When the processing circuit receives a read command from the host interface, it outputs the first physical quantity and the second physical quantity of the triaxial physical quantities obtained from the first sensor located outside the semiconductor package via the first interface to the host via the host interface. When sending the third physical quantity of the triaxial physical quantities obtained from the first sensor via the first interface, it replaces the third physical quantity with the high-precision third physical quantity obtained from the second sensor via the second interface inside the semiconductor package and outputs it to the host, thereby outputting the triaxial physical quantities including the first physical quantity, the second physical quantity, and the high-precision third physical quantity to the host via the host interface.

2. The inertial sensor device according to claim 1, characterized in that, The third physical quantity and the high-precision third physical quantity are the angular velocities about the third detection axis.

3. The inertial sensor device according to claim 1 or 2, characterized in that, The third physical quantity and the high-precision third physical quantity are the accelerations on the third detection axis.

4. The inertial sensor device according to claim 1, characterized in that, The processing circuit performs zero-point calibration on the first physical quantity, the second physical quantity, and the high-precision third physical quantity. The host interface will output the first physical quantity, the second physical quantity, and the high-precision third physical quantity after zero-point calibration to the host.

5. The inertial sensor device according to claim 1, characterized in that, The processing circuit performs alignment correction between the detection axes for the first physical quantity, the second physical quantity, and the high-precision third physical quantity. The host interface will output the first physical quantity, the second physical quantity, and the high-precision third physical quantity after alignment correction to the host.

6. The inertial sensor device according to claim 1, characterized in that, The first sensor is a MEMS inertial sensor. The second sensor is a crystal inertial sensor.

7. A sensor module, characterized in that, include: The inertial sensor device according to any one of claims 1 to 6; as well as The first sensor.

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