Inertial Sensor Module

Abstract

To provide an inertia sensor module that does not require the sensitivity on a host side.SOLUTION: An inertia sensor module 100 includes: a first sensor 110; a second sensor 120; and a processing circuit 130. The first sensor 110 detects a first physical amount P1 at a first detection axis and a second physical amount P2 at a second detection axis, with a first sensitivity. The second sensor 120 detects a third detection amount P3 at a third detection axis more accurately than the first sensor does, with a second sensitivity different from the first sensitivity. The processing circuit 130 performs operation processing of converting the first physical amount P1 for the first sensitivity, the second physical amount P2, and the third amount P3 for the second sensitivity to a first physical amount PP1, a second physical amount PP2, and a third physical amount PP3 for a predetermined sensitivity.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an inertial sensor module and the like. [Background technology]

[0002] Patent Document 1 describes a three-axis angular velocity sensor and a three-axis acceleration sensor, each having a movable portion made of silicon, formed on the substrate of a single host device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-031358 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the sensitivity and other specifications may differ depending on the sensor. Therefore, if multiple sensors with different sensitivities are mounted on the board of a single host device, adjustments to align the sensitivities on the host device side become complicated. [Means for solving the problem]

[0005] One aspect of the present disclosure relates to an inertial sensor module including: a first sensor that detects a first physical quantity on a first detection axis and a second physical quantity on a second detection axis with a first sensitivity; a second sensor that detects a third physical quantity on a third detection axis with a second sensitivity different from the first sensitivity and with higher accuracy than the first sensor; and a processing circuit that performs processing to convert the first physical quantity and the second physical quantity at the first sensitivity and the third physical quantity at the second sensitivity into the first physical quantity, the second physical quantity, and the third physical quantity at a predetermined sensitivity. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a block diagram illustrating an example of the configuration of an embodiment of the present invention. [Figure 2] 5A and 5B are diagrams illustrating an example of the relationship between a detection range and a first scale factor. [Figure 3] 10 is a flowchart illustrating an example of calculation processing. [Figure 4] 10 is a flowchart illustrating an example of a sensitivity correction process. [Figure 5] FIG. 10 is a diagram illustrating an example of a second scale factor. [Figure 6] FIG. 10 is a block diagram illustrating a modified example of the present embodiment. [Figure 7] FIG. 3 is a diagram illustrating the relationship between a first input rate, a second input rate, and a predetermined output rate. [Figure 8] 10 is a timing chart illustrating a modified method. [Figure 9] 10 is another timing chart illustrating the technique of the modified example. [Figure 10] FIG. 10 is a block diagram illustrating another modified example of the embodiment. [Figure 11] FIG. 4 is a diagram illustrating the relationship between a first detection axis, a second detection axis, and a third detection axis. [Figure 12] 10A and 10B are diagrams illustrating an example of a problem of a detection error of a third physical quantity. DETAILED DESCRIPTION OF THE INVENTION

[0007] Preferred embodiments of the present disclosure will be described in detail below. Note that the embodiments described below do not unduly limit the scope of the claims, and not all of the configurations described in the embodiments are necessarily essential components.

[0008] 1 is a block diagram showing an example of the configuration of an inertial sensor module 100 according to this embodiment. The inertial sensor module 100 according to this embodiment includes a first sensor 110, a second sensor 120, and a processing circuit .

[0009] The first sensor 110 detects a physical quantity in the X-axis direction, which is the first detection axis, as a first physical quantity P1 with a first sensitivity. Similarly, the first sensor 110 detects a physical quantity in the Y-axis direction, which is the second detection axis, as a second physical quantity P2 with a first sensitivity. The first sensitivity will be described later. Although not shown in FIG. 1, the first sensor 110 includes a sensor element for detecting a physical quantity in the X-axis or Y-axis and an analog circuit having an amplifier circuit or the like for amplifying a detection signal from the sensor element, and outputs an analog signal from the analog circuit. Although also not shown in FIG. 1, the first sensor 110 may further include an A / D conversion circuit or the like for converting the analog signal from the analog circuit into digital data. This allows the output data of the A / D conversion circuit or digital data obtained by performing correction processing such as temperature correction on the output data to be output. The number of bits of the A / D conversion circuit included in the first sensor 110 is referred to as a first bit number. Note that one sensor element may be able to detect physical quantities in both the X-axis direction and the Y-axis direction, or there may be a sensor element that detects physical quantities in the X-axis direction and a sensor element that detects physical quantities in the Y-axis direction. In the following description, digital data may simply be referred to as data. In the following description, the digital data transmitted by the first sensor 110 or the first physical quantity P1 and the second physical quantity P2 obtained by multiplying the digital data by the first bit number may be collectively referred to as first sensor data. The same applies to the modified examples described below.

[0010] Furthermore, the physical quantity may be, for example, acceleration, but may also be angular velocity or another physical quantity. For example, if the physical quantity is acceleration, the first sensor 110 is a biaxial acceleration sensor, and may be realized, for example, by a capacitive Si-MEMS sensor device capable of detecting acceleration in both the X-axis and Y-axis directions in a single device. However, the first sensor 110 is not limited to this and may be realized by a frequency-change quartz acceleration sensor, a piezoresistive acceleration sensor, or a thermal detection acceleration sensor. For example, if the physical quantity is angular velocity, the first sensor 110 is a biaxial angular velocity sensor, and may be realized, for example, by a Si-MEMS sensor device, or may be realized by a resonant frequency-change quartz angular velocity sensor made of quartz that detects angular velocity from the Coriolis force applied to a vibrating object. Angular velocity sensors are also called gyro sensors.

[0011] The second sensor 120 detects a physical quantity in the Z-axis direction, which is the third detection axis, with a second sensitivity as a third physical quantity P3. The second sensitivity will be described later. Although not shown in FIG. 1, the second sensor 120 includes a sensor element for detecting the physical quantity in the Z-axis direction and an analog circuit having an amplifier circuit or the like for amplifying the detection signal from the sensor element, and outputs an analog signal from the analog circuit. Although also not shown in FIG. 1, the second sensor 120 may further include an A / D conversion circuit or the like for converting the analog signal from the analog circuit into digital data. This allows the second sensor 120 to output output data from the A / D conversion circuit or digital data obtained by performing correction processing, such as temperature correction, on the output data. The number of bits of the A / D conversion circuit included in the second sensor 120 is referred to as the second bit number. The second sensor 120 can be realized using various sensors, similar to the first sensor, but its specifications, such as sensitivity, may differ from those of the first sensor 110. In the following description, the digital data transmitted by the second sensor 120 or the third physical quantity P3 obtained by multiplying the digital data by the second bit number may be collectively referred to as second sensor data. The same applies to modified examples described later.

[0012] In the following description, the detection axis parallel to the X-axis may 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. Furthermore, the X-axis physical quantity data output by the first sensor 110 may be referred to as the first physical quantity P1, and the Y-axis physical quantity data may be referred to as the second physical quantity P2. Similarly, the Z-axis physical quantity data output by the second sensor 120 may be referred to as the third physical quantity P3. Furthermore, the angular velocity around the first detection axis may be referred to as the first angular velocity G1, the angular velocity around the second detection axis as the second angular velocity G2, and the angular velocity around the third detection axis as the third angular velocity G3. Furthermore, the acceleration around the first detection axis may be referred to as the first acceleration A1, the acceleration around the second detection axis as the second acceleration A2, and the acceleration around the third detection axis as the third acceleration A3. As a result, the first sensor 110 detects a first physical quantity P1 on the first detection axis and a second physical quantity P2 on the second detection axis with the first sensitivity, and the second sensor 120 detects a third physical quantity P3 on the third detection axis with the second sensitivity.

[0013] The processing circuit 130 performs processing for each component of the inertial sensor module 100. For example, the processing circuit 130 performs processing to control the first sensor 110, the second sensor 120, etc. For example, if the first sensor 110 and the second sensor 120 are digital physical quantity sensors, the processing circuit 130 communicates with the first sensor 110 and the second sensor 120 via digital data and serves as a master controller for the first sensor 110 and the second sensor 120. The processing circuit 130 is configured with the following hardware. The hardware includes a circuit for processing digital signals and may also include a circuit for processing analog signals. For example, the hardware may be configured with 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 integrated circuit (IC), a field-programmable gate array (FPGA), etc. The one or more circuit elements are, for example, a resistor, a capacitor, etc. The processing circuit 130 is also realized by including at least one of the following processors: The processing circuit 130 includes a memory (not shown in FIG. 1 ) that stores information and a processor that operates based on the information stored in the memory. The information may be, for example, a program and various data. The processor includes hardware. Various types of processors may be used, such as a central processing unit (CPU), a graphics processing unit (GPU), or a digital signal processor (DSP). The memory may be a semiconductor memory such as a static random access memory (SRAM) or a dynamic random access memory (DRAM), a register, a magnetic storage device such as a hard disk drive (HDD), or an optical storage device such as an optical disk drive. For example, the memory stores computer-readable instructions, and the processor executes the instructions to realize some or all of the functions of the components of the processing circuit 130.The instruction here may be an instruction from an instruction set that constitutes a program, or an instruction that instructs the hardware circuitry of the processor to operate.

[0014] Next, we will explain the first and second sensitivities. Sensitivity refers to the change in output per unit of a physical quantity input to a physical quantity sensor, and is also called gain. The degree of sensitivity is also called the sensitivity coefficient or scale factor SF. For example, when comparing multiple analog acceleration sensors, the scale factor SF may be expressed in units such as [mV / g], where g is the acceleration value relative to standard gravity. In this case, when the same physical quantity is input to the sensor elements of each acceleration sensor, the acceleration sensor that outputs a higher voltage value has a larger scale factor SF, i.e., a higher sensitivity. Note that the scale factor SF may also be expressed in units of the opposite dimension, such as [g / mV]. When the physical quantity sensor is a digital acceleration sensor, for example, the analog output voltage value is A / D converted by the A / D conversion circuit mentioned above, and the scale factor SF is expressed in units such as [g / LSB] or [LSB / g]. In other words, sensitivity is related to the first and second bit numbers.

[0015] In the following description, the representative value of the scale factor SF shown in the data sheet will be referred to as the first scale factor SF1, and temperature dependency will not be taken into consideration. In the following description, the first scale factor SF1 of the first sensor 110 will be denoted as SF11, the first scale factor SF1 of the second sensor 120 will be denoted as SF12, etc., and the first scale factor SF1 of the inertial sensor module 100 will be denoted as SFP. The first scale factor SF1P of the inertial sensor module 100 will sometimes be denoted as a predetermined scale factor SF1P.

[0016] Sensitivity is also related to the detection range. The detection range is also called full scale or rated, but it is not an absolute rating. For example, suppose a datasheet for a digital physical quantity sensor shows the first scale factor SF1 as D1, D2, D3, and D4 in Figure 2. Note that specific units are omitted in Figure 2. For example, if the first scale factor SF1 shown in D1 is multiplied by 16-bit resolution, the result may be larger than the detection range and may not match, as shown in D5. In other words, if a digital value close to the upper or lower limit of the detection range is detected, it is necessary to confirm whether it can be treated as valid data. Note that comparing D1 and D2 in Figure 2, if the detection range of the physical quantity is doubled, the first scale factor SF1 is doubled. Similarly, comparing D1 and D3, if the detection range of the physical quantity is tripled, the first scale factor SF1 is tripled. Similarly, comparing D1 and D4, if the detection range of the physical quantity is quadrupled, the first scale factor SF1 is quadrupled. That is, if the detection range of the first sensor 110 is changed, the first scale factor SF11 will also be changed. The same applies to the first scale factor SF12 of the second sensor 120.

[0017] In this way, when the first scale factor SF11 of the first sensor 110 and the first scale factor SF12 of the second sensor 120 are different, if the first sensor data and the second sensor data are output as is from the inertial sensor module 100, the output destination device cannot convert the data into accurate physical quantities unless it prepares a different conversion coefficient for each sensor. Furthermore, the output destination device may need to check whether the output first sensor data and second sensor data are within the detection range when converted into physical quantities.

[0018] In this regard, in this embodiment, the processing circuit 130 performs a calculation process to convert the first physical quantity P1 and the second physical quantity P2 having the first sensitivity and the third physical quantity P3 having the second sensitivity into the first physical quantity PP1, the second physical quantity PP2, and the third physical quantity PP3 having a predetermined sensitivity. This calculation process can be realized, for example, by the following method. For example, assume that the first sensor 110 is an analog acceleration sensor having a first scale factor SF11 value AS1 [mV / g] and the second sensor 120 is an analog acceleration sensor having a first scale factor SF12 value AS2 [mV / g]. In this case, the processing circuit 130 multiplies the voltage value acquired from the first sensor 110 by the value of the second scale factor SF21 (=AS2 / AS1), and outputs the result as the first acceleration PA1 and the second acceleration PA2 having the predetermined sensitivity. On the other hand, the processing circuit 130 outputs the voltage value acquired from the second sensor 120 as the third acceleration PA3 having the predetermined sensitivity. In this way, the inertial sensor module 100 can output the first acceleration PA1, the second acceleration PA2, and the third acceleration PA3 with predetermined sensitivity as an acceleration sensor with a predetermined scale factor SF1P value AS2 [mV / g]. This allows the inertial sensor module 100 to output acceleration data with unified sensitivity. Note that although the above description has been given of the case where the first sensor 110 and the second sensor are analog acceleration sensors, they may also be analog angular velocity sensors, etc.

[0019] As described above, the inertial sensor module 100 of this embodiment includes the first sensor 110, the second sensor 120, and the processing circuit 130. The first sensor 110 detects a first physical quantity P1 on a first detection axis and a second physical quantity P2 on a second detection axis with a first sensitivity. The second sensor 120 detects a third physical quantity P3 on a third detection axis with a second sensitivity different from the first sensitivity and with higher accuracy than the first sensor. The processing circuit 130 performs a calculation process that converts the first physical quantity P1 and the second physical quantity P2 at the first sensitivity and the third physical quantity P3 at the second sensitivity into a first physical quantity PP1, a second physical quantity PP2, and a third physical quantity PP3 at a predetermined sensitivity.

[0020] As described above, the inertial sensor module 100 of this embodiment can acquire the first physical quantity P1 on the first detection axis and the second physical quantity P2 on the second detection axis from the first sensor 110, and can acquire the third physical quantity P3 from the second sensor 120. This allows the inertial sensor module 100 to function as a three-axis physical quantity sensor. Furthermore, the inertial sensor module 100 of this embodiment includes a processing circuit 130, which can convert the first physical quantity P1 and the second physical quantity P2 at the first sensitivity and the third physical quantity P3 at the second sensitivity into the first physical quantity PP1, the second physical quantity PP2, and the third physical quantity PP3 at a predetermined sensitivity. Conventional techniques require adjustment of the sensitivity on the device that outputs the sensor data from the inertial sensor module 100. In this regard, the method of this embodiment can facilitate adjustment without changing the specifications of the connection side. While the third detection axis has been described above as the Z axis, the third detection axis may be the X axis or the Y axis. In the following description, the first physical quantity PP1, the second physical quantity PP2, and the third physical quantity PP3 with a predetermined sensitivity output from the processing circuit 130 may be collectively referred to as predetermined sensor data.

[0021] As described above, the physical quantities of this embodiment may specifically be, for example, angular velocities. That is, the first physical quantity P1 is a first angular velocity G1 as an angular velocity about the first detection axis, the second physical quantity P2 is a second angular velocity G2 as an angular velocity about the second detection axis, and the third physical quantity P3 is a third angular velocity G3 as an angular velocity about the third detection axis. By applying the method of this embodiment described above in this manner, the processing circuit 130 can output the first angular velocity PG1 with a predetermined sensitivity, the second angular velocity PG2 with a predetermined sensitivity, and the third angular velocity PG3 with a predetermined sensitivity.

[0022] As described above, the physical quantities of this embodiment may be, for example, accelerations. That is, the first physical quantity is a first acceleration A1 as an acceleration on a first detection axis, the second physical quantity is a second acceleration A2 as an acceleration on a second detection axis, and the third physical quantity is a third acceleration A3 as an acceleration on a third detection axis. By applying the method of this embodiment described above in this manner, the processing circuit 130 can output the first acceleration PA1 with a predetermined sensitivity, the second acceleration PA2 with a predetermined sensitivity, and the third acceleration PA3 with a predetermined sensitivity.

[0023] Furthermore, the method of this embodiment is not limited to the above, and various modifications are possible. For example, the method of this embodiment can also be applied to a case where the first sensor 110 and the second sensor 120 are digital physical quantity sensors. An example of the calculation process in this case will be described using the flowcharts of FIGS. 3 and 4. Note that the issue of input / output timing is not taken into consideration in FIGS. 3 and 4. In other words, it is assumed that the first sensor data and the second sensor data are input to the processing circuit 130 in synchronization with each other, and that predetermined sensor data is output at a timing after the processing in FIGS. 3 and 4 has been completed. An example of taking timing into consideration will be described later.

[0024] The processing circuit 130 determines whether the sensitivity of the first sensor 110 and the sensitivity of the second sensor 120 are the same (step S10). Specifically, for example, the first scale factor SF11 of the first sensor 110 and the first scale factor SF12 of the second sensor 120 are stored in a storage unit (not shown) in advance, and a process of comparing the two is performed. If the sensitivity of the first sensor 110 and the sensitivity of the second sensor 120 are the same (YES in step S10), the processing circuit 130 checks the value of the first sensor data acquired from the first sensor 110 (step S20). Specifically, for example, the processing circuit 130 performs a process of checking whether the value of a first physical quantity P1 obtained by multiplying the acquired first sensor data by a first bit number is within the detection range. Note that, although not shown in the figure, if the value of the first physical quantity P1 is outside the detection range, the first sensor data may be output by fixing the value to the maximum or minimum value within the detection range, or the first sensor data may not be output at all.

[0025] After performing the process of step S20, the processing circuit 130 checks the value of the second sensor data acquired from the second sensor 120 (step S30). Specifically, for example, the processing circuit 130 performs a process of checking whether a second physical quantity P2 obtained by multiplying the acquired second sensor data by the second bit number is within the detection range. Note that, although the process is not illustrated, if the value of the second physical quantity P2 is outside the detection range, the second sensor data may be fixed to the maximum or minimum value within the detection range and output, or the second sensor data may not be output at all.

[0026] On the other hand, if the sensitivity of the first sensor 110 and the sensitivity of the second sensor 120 are different (NO in step S10), the processing circuit 130 performs sensitivity correction (step S100).

[0027] FIG. 4 is a flowchart illustrating an example of the sensitivity correction process (step S100). The processing circuit 130 performs a process of unifying the number of bits of the first sensor data and the number of bits of the second sensor data (step S102). Specifically, for example, the processing circuit 130 performs a process of unifying the first number of bits and the second number of bits to a predetermined number of bits. The predetermined number of bits is, for example, the larger of the first number of bits and the second number of bits, but may be a number of bits different from the first number of bits and the second number of bits. For example, if the first number of bits is 15 bits and the second number of bits is 16 bits and it is desired to unify the predetermined number of bits to 16 bits, the processing circuit 130 performs a process of converting the 15-bit first sensor data to 16 bits and does not perform any process on the second sensor data. As a result, the first sensor data and the second sensor data are unified as data of 16 bits, which is the predetermined number of bits. In this case, for example, the processing circuit 130 multiplies the first sensor data by 2, and also multiplies the first scale factor SF11 of the first sensor 110 by 1 / 2.

[0028] Thereafter, the processing circuit 130 performs a process of multiplying the first sensor data by the second scale factor SF2 (step S104). Specifically, the processing circuit 130 performs a process of multiplying the first sensor data by the second scale factor SF21 and the second sensor data by the second scale factor SF22. The second scale factors SF21 and SF22 can be calculated, for example, using the following method. For example, the processing circuit 130 calculates first scale factors SF11, SF12, and SF1P when the number of bits is unified to a predetermined number. Then, the processing circuit 130 calculates second scale factors SF21 and SF22 so that the product of the first scale factor SF11 and the second scale factor SF21 and the product of the first scale factor SF12 and the second scale factor SF22 are equal to the first scale factor SF1P. The above process can be specifically illustrated, for example, as shown in FIG. 5. Note that specific units are omitted in Figure 5, and the specific values ​​of the first scale factors SF11, SF12, and SF1P and the second scale factors SF21 and SF22 are not necessarily as shown in Figure 5. For example, assume that the value of the first scale factor SF11 is 0.5, the value of the first scale factor SF12 is determined to be 4, and the value of the first scale factor SF1P is set to 1. In this case, the value of the second scale factor SF21 is determined to be 2, and the value of the second scale factor SF21 is determined to be 0.25. In this way, the digital inertial sensor module 100 can output the first physical quantity PP1, the second physical quantity PP2, and the third physical quantity PP3 that are unified by the first scale factor SF1P of the inertial sensor module 100.

[0029] Returning to FIG. 3 , after performing the sensitivity correction (step S100), the processing circuit 130 checks the value of the predetermined sensor data (step S110). Specifically, the processing circuit 130 multiplies the predetermined sensor data after the sensitivity correction (step S100) by a predetermined number of bits to determine the values ​​of the first physical quantity PP1, the second physical quantity PP2, and the third physical quantity PP3 at the predetermined sensitivity. The processing circuit 130 then checks whether the values ​​of the first physical quantity PP1, the second physical quantity PP2, and the third physical quantity PP3 at the predetermined sensitivity are within the detection range set in the inertial sensor module 100. Although the process is not illustrated, if the calculated values ​​of the first physical quantity PP1, the second physical quantity PP2, and the third physical quantity PP3 at the predetermined sensitivity are outside the detection range, the predetermined sensor data may be fixed to the maximum or minimum value within the detection range and output, or the predetermined sensor data may not be output.

[0030] The method of this embodiment is not limited to the above, and various modifications are possible. For example, the inertial sensor module 100 of this embodiment may be configured as shown in the block diagram of FIG. 6 as a modified example. The example shown in FIG. 6 differs from the example of FIG. 1 in that the inertial sensor module 100 further includes a first interface 131, a second interface 132, and a host interface 133. For example, the processing circuit 130, the first interface 131, the second interface 132, and the host interface 133 within the dotted line indicated by M can be realized by a single microcontroller.

[0031] The first interface 131 is a circuit that performs interface processing related to sending and receiving digital data to and from the first sensor 110 in accordance with a predetermined communication method. The predetermined communication method is, for example, a predetermined serial communication method, but may also be a parallel communication method. Furthermore, the predetermined serial communication method is a synchronous SPI (Serial Peripheral Interface), but may also be an I2C (Inter-Integrated Circuit) or UART (Universal Asynchronous Receiver Transmitter), or may be a communication method that is a partial improvement or modification of these communication methods.

[0032] The first sensor 110 and the first interface 131 are electrically connected by a first digital interface bus BS1. Sensor data from the first sensor 110 is input to the first interface 131 via the first digital interface bus BS1. The first digital interface bus BS1 is a bus that complies with the communication standard of the interface processing performed by the first interface 131. For example, if the first interface 131 complies with SPI, as shown in FIG. 6, the first digital interface bus BS1 is composed of four signal lines including signal lines CS1, DIN1, DOUT1, and CLK1. In the following description, CS1 may be used to refer to both the signal line and the signal passing through the signal line. The same applies to the signal line CLK1.

[0033] The second interface 132 is a circuit that performs interface processing related to sending and receiving digital data to and from the second sensor 120 in accordance with a predetermined communication method. The predetermined communication method is as described above. The communication method followed by the second interface 132 may be the same as or different from the communication method followed by the first interface 131.

[0034] The second sensor 120 and the second interface 132 are electrically connected by a second digital interface bus BS2. Sensor data from the second sensor 120 is input to the second interface 132 via the second digital interface bus BS2. The second digital interface bus BS2 is a bus that complies with the communication standard of the interface processing performed by the second interface 132. For example, if the second interface 132 complies with SPI, as shown in FIG. 6, the second digital interface bus BS2 is composed of four signal lines including signal line CS2, signal line DIN2, signal line DOUT2, and signal line CLK2. Note that in the following description, CS2 may be used to refer to both the signal line and the signal passing through the signal line. The same applies to the signal line CLK2.

[0035] The host interface 133 is a circuit that performs interface processing related to sending and receiving data with the host 200 (described later) in accordance with a predetermined communication method. The predetermined communication method is as described above. The communication method followed by the host interface 133 may be the same as or different from the communication method followed by the first interface 131 or the second interface 132.

[0036] The host 200 is a device electrically connected to the inertial sensor module 100 and the like, and acquires physical quantities output from the inertial sensor module 100. The host 200 includes a processing unit (not shown), which can be implemented by 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 each component of the measurement system. Based on the physical quantities acquired by the host 200, the measurement system can calculate the position of a predetermined measurement object. Examples of the predetermined measurement object include, but are not limited to, moving objects such as bicycles, four-wheeled automobiles, motorcycles, trains, airplanes, and ships, as well as electronic devices such as personal computers, smartphones, tablet devices, watches, car navigation systems, and various measuring instruments. For example, the measurement system can calculate the position of a predetermined measurement object by including the host 200 and a GPS receiver and a GPS receiving antenna (not shown). Specifically, the GPS receiver receives signals from GPS satellites via an antenna, and the host 200 detects GPS positioning data representing the position, speed, and orientation of a specific measurement object based on the signals received by the GPS receiver. The position of the specific measurement object is, for example, latitude, longitude, or altitude. The host 200 also performs inertial navigation calculation processing on the physical quantity data acquired from the inertial sensor module 100 to obtain inertial navigation positioning data. The inertial navigation positioning data includes acceleration data and attitude data of the measurement object. The host 200 then calculates the position of the specific measurement object based on the obtained inertial navigation positioning data and GPS positioning data. For example, if the specific measurement object is a four-wheeled vehicle, the host 200 calculates the position of the four-wheeled vehicle on the ground.

[0037] The host 200 and the host interface 133 are electrically connected by a predetermined digital interface bus BSP. Data from the host interface 133 is input to an interface (not shown) of the host 200 via the predetermined digital interface bus BSP. In the following description, receiving data at an interface (not shown) of the host 200 may be simply referred to as the host 200 receiving data. The predetermined digital interface bus BSP is a bus that complies with the communication standard for interface processing performed by the host interface 133, etc. For example, if the host interface 133 complies with SPI, as shown in FIG. 6, the predetermined digital interface bus BSP is composed of four signal lines, including signal lines CSP, DINP, DOUTP, and CLKP. In the following description, CSP may be used to refer to both the signal line and the signal passing through the signal line. The same applies to the signal line CLKP.

[0038] It should be noted that other features may be added to the exemplary configuration shown in FIG. 6. For example, although not shown in FIG. 6, a predetermined signal line DRDY1 may be connected between the first sensor 110 and the processing circuit 130. Furthermore, although not shown in FIG. 6, a signal line DRDYP may be connected between the host 200 and the processing circuit 130. In this way, for example, the first sensor 110, which is the slave, can notify the processing circuit 130, which is the master, of the start of communication. In the following description, the signal line DRDY1 may be used to mean both the signal line and the signal passing through the signal line. The same applies to the signal line DRDYP.

[0039] As described above, the inertial sensor module 100 of this embodiment includes a first interface 131 that is an interface with the first sensor 110, a second interface 132 that is an interface with the second sensor 120, and a host interface 133 that is an interface with the host 200. The host interface 133 outputs the first physical quantity PP1, the second physical quantity PP2, and the third physical quantity PP3 at a predetermined sensitivity to the host 200. As described above, the inertial sensor module 100 of this embodiment includes the first interface 131, the second interface 132, and the host interface 133, and is therefore capable of transmitting and receiving data to and from the first sensor 110, the second sensor 120, and the host 200. The host interface 133 is also capable of outputting the first physical quantity PP1, the second physical quantity PP2, and the third physical quantity PP3, the sensitivities of which are unified to a predetermined sensitivity, to the host 200.

[0040] In the above example, it was assumed that there was no problem with the timing at which the processing circuit 130 received the first sensor data from the first sensor 110 and the timing at which the processing circuit 130 received the second sensor data from the second sensor 120. However, due to certain circumstances, the timing at which the processing circuit 130 received the first sensor data from the first sensor 110 and the timing at which the processing circuit 130 received the second sensor data from the second sensor 120 may differ. The certain circumstances may be, for example, a situation in which the user wants to consider the history of receiving and using the first sensor data from the first sensor 110 at a first input rate R1 and the history of receiving and using the second sensor data from the second sensor 120 at a second input rate R2. In this case, if the first input rate R1 and the second input rate R2 differ, the timing at which the processing circuit 130 received the first sensor data and the timing at which the processing circuit 130 received the second sensor data may not necessarily be synchronized.

[0041] However, as will be described in detail later, the method of this embodiment can also be applied when the first input rate R1 and the second input rate R2 are different. That is, in the inertial sensor module 100 of this embodiment, the first sensor 110 inputs a first physical quantity P1 and a second physical quantity P2 having a first sensitivity to the first interface 131 at the first input rate R1, and the second sensor 120 inputs a third physical quantity P3 having a second sensitivity to the second interface 132 at a second input rate R2 that is different from the first input rate R1. In this way, the inertial sensor module 100 including sensors having different input rates can output predetermined sensor data with uniform sensitivity.

[0042] In this case, as will be described in detail later, predetermined sensor data whose output rate is unified to a predetermined output rate RP is output from the host interface 133. That is, in the inertial sensor module 100 of this embodiment, the host interface 133 outputs the first physical quantity PP1, the second physical quantity PP2, and the third physical quantity PP3, each having a predetermined sensitivity, to the host 200 at the predetermined output rate RP. In this way, it is possible to output predetermined sensor data whose sensitivity and output rate are unified.

[0043] Here, the input period corresponding to the first input rate R1 is defined as the first period T1, the input period corresponding to the second input rate R2 is defined as the second period T2, and the output period corresponding to the predetermined output rate RP is defined as the predetermined period TP. As shown in FIG. 7, the first period T1 is shorter than the predetermined period TP, and the second period T2 is also shorter than the predetermined period TP, and the first period T1 is different from the second period T2. In other words, in the inertial sensor module 100 of this embodiment, the rate of the predetermined output rate RP is lower than the rates of the first input rate R1 and the second input rate R2. This allows the predetermined period TP on the output side to be longer than the first period T1 and the second period T2 on the input side, thereby enabling the first sensor data and the second sensor data on the input side to be output synchronously. While the predetermined period TP is illustrated as being twice the second period T2 in FIG. 7, it need not be twice as long.

[0044] 8 and 9, a specific method for outputting the first physical quantity PP1, the second physical quantity PP2, and the third physical quantity PP3 of predetermined sensitivity to the host 200 at a predetermined output rate RP will be described. Fig. 8 is a timing chart showing the relationship between data passing through the first digital interface bus BS1, the arithmetic processing in the processing circuit 130, and the data passing through the predetermined digital interface bus BSP. Note that the timing of the arithmetic processing, signal DRDYP, and predetermined digital interface bus BSP shown in Fig. 8 is the same as the timing of the arithmetic processing, signal DRDYP, and predetermined digital interface bus BSP shown in Fig. 9.

[0045] As shown in FIG. 8 , the first sensor 110 samples first sensor data using a sensor element (not shown) during the first period T1, as indicated by E1, E2, E3, E4, and E5. The first sensor 110 also sets the aforementioned signal DRDY1 to an H level during the first period T1, causing the first interface 131 (the master) to acquire the first sensor data from the first sensor 110 (the slave). This causes the first sensor data to be transmitted to the first digital interface bus BS1 during the first period T1, as indicated by F1, F2, F3, and F4. More specifically, although not shown, the first interface 131 sets the negative logic signal CS1 to an L level when the signal DRDY1 goes H. The first interface 131 then transmits data to the first sensor 110 via the signal line DOUT1 and receives the first sensor data via the signal line DIN1, in synchronization with the signal CLK1. That is, the signal CLK1 is based on an oscillator circuit (not shown) included in the processing circuit 130 or the first interface 131, but the first period T1, which is the input period of the first sensor data, is based on an oscillator circuit (not shown) on the first sensor 110 side.

[0046] The processing circuit 130 performs arithmetic processing based on the acquired first sensor data and second sensor data (not shown in FIG. 8). Specifically, the processing circuit 130 performs arithmetic processing at a predetermined cycle TP, as shown in C1 and C2. The first sensor data used in the arithmetic processing is based on the most recently acquired data. For example, the arithmetic processing shown in C2 is performed using the first sensor data acquired by data acquisition shown in F2, i.e., the first sensor data sampled by sampling shown in E2.

[0047] As shown by K1, K2, K3, K4, and K5 in FIG. 9 , the second interface 132, which is the master, acquires second sensor data from the second sensor 120, which is the slave, at the second period T2. More specifically, although not shown, the second interface 132 sets the signal CS2 to the L level at each second period T2. The second interface 132 then receives the second sensor data via the signal line DIN2 in synchronization with the signal CLK2 and transmits the data to the second sensor 120 via the signal line DOUT2. That is, the signal CLK2 is generated by an oscillator circuit (not shown) included in the processing circuit 130 or the second interface 132, and the second period T2, which is the input period of the second sensor data, is also generated by the same oscillator circuit. Therefore, the oscillator circuit based on the predetermined period TP may be the same as the oscillator circuit based on the second period T2, and the predetermined output rate RP may be achieved by dividing the frequency from the oscillator circuit based on the second input rate R2. Note that the data transmitted via the signal line DOUT2 is a don't care.

[0048] Furthermore, as shown by J1, J2, J3, J4, J5, J6, J7, J8, J9, J10, and J11 in FIG. 9, the second sensor 120 can sample the second sensor data at a period shorter than the second period T2. While FIG. 9 illustrates the second period T2 as being twice the sampling period, it need not be twice as long. In this case, for example, the acquisition of the second sensor data indicated by K1 is performed by obtaining the average value of the second sensor data obtained by the sampling indicated by J1 and J2. The second sensor data used in the calculation process described above in FIG. 8 is based on the most recently acquired data. For example, in the calculation process indicated by C2, the acquired data indicated by K3, i.e., the average value of the second sensor data sampled at J5 and J6, is used. Similarly, in the calculation process indicated by C3, the acquired data indicated by K5, i.e., the average value of the second sensor data sampled at J9 and J10, is used.

[0049] The processing circuit 130 outputs predetermined sensor data at predetermined cycles TP, as indicated by N1 and N2. Specifically, the processing circuit 130 sets the signal DRDYP to H level each time it completes a calculation process. This causes the master host 200 to transmit and receive data from the slave host interface 133. More specifically, although not shown, when the signal DRDYP goes H level, the host 200 sets the negative logic signal CSP to L level. Then, in synchronization with the signal CLKP, the host 200 transmits data to the host interface 133 via the signal line DOUTP, and receives the predetermined sensor data after calculation process, i.e., the first physical quantity PP1, the second physical quantity PP2, and the third physical quantity PP3 with predetermined sensitivity, via the signal line DINP. In other words, the signal CLKP is generated based on an oscillator circuit (not shown) included in the host 200, while the predetermined cycle TP, which is the output cycle from the host interface 133, is generated based on an oscillator circuit included in the processing circuit 130 or the host interface 133. Note that the data transmitted via the signal line DOUTP is a don't care signal. For example, the predetermined sensor data indicated by N2 is based on the calculation process indicated by C2, and therefore, predetermined sensor data obtained by calculating the first sensor data sampled at E2 in Fig. 8 and the average value of the second sensor data sampled at J5 and J6 in Fig. 9 is output to the host 200. In this way, the host interface 133 can output the first physical quantity PP1, the second physical quantity PP2, and the third physical quantity PP3 of predetermined sensitivity to the host 200 at a predetermined output rate RP corresponding to the predetermined period TP.

[0050] The method of the present embodiment is not limited to this, and modifications such as adding other features are possible. For example, although the first sensor 110 has been described above as a biaxial sensor, the first sensor 110 may be a triaxial sensor. Furthermore, if the second sensor 120 has higher accuracy than the first sensor 110, the above-described method may be combined with a method of replacing part of the first sensor data with the second sensor data. Specifically, as shown in FIG. 10 , in the inertial sensor module 100 of the present embodiment, the first sensor 110 detects a low-accuracy third physical quantity LP3 about the third detection axis, and the second sensor 120 detects a high-accuracy third physical quantity HP3 about the third detection axis. Furthermore, the processing circuit 130 outputs the high-accuracy third physical quantity HP3 input via the second interface to the host 200 via the host interface 133, instead of the low-accuracy third physical quantity LP3 input via the first interface 131. Here, high accuracy refers to a high S / N ratio or a small error. For example, when the signal strengths output by the sensor elements of the first sensor 110 and the second sensor 120 are the same, the ratio of noise strength to the signal strength is smaller in the second sensor 120. Alternatively, the ratio of error to the signal strength output by the sensor elements of the second sensor 120 is smaller than the ratio of error to the signal strength output by the sensor elements of the first sensor 110.

[0051] By combining these techniques, the first sensor 110 detects a low-precision third physical quantity LP3 with a first sensitivity on the third detection axis, and the second sensor 120 detects a high-precision third physical quantity HP3 with a second sensitivity on the third detection axis. Furthermore, the processing circuit 130 outputs the low-precision first physical quantity PLP1 with a predetermined sensitivity, the low-precision second physical quantity PLP2 with a predetermined sensitivity, and the high-precision third physical quantity PHP3 with a predetermined sensitivity to the host 200 via the host interface 133. In this way, it is possible to output sensor data that is unified to a predetermined sensitivity and has high precision on any axis.

[0052] Such communication can be realized, for example, by the following method. For example, the first sensor 110 transmits a low-accuracy first physical quantity LP1, a low-accuracy second physical quantity LP2, and a low-accuracy third physical quantity LP3 as serial data conforming to the SPI standard to the first interface 131 via a signal line DOUT1. Furthermore, the second sensor 120 transmits a high-accuracy third physical quantity HP3 as serial data conforming to the SPI standard to the second interface 132 via a signal line DOUT2. The processing circuit 130 performs the above-mentioned arithmetic processing on the low-accuracy first physical quantity LP1 and the low-accuracy second physical quantity LP2 out of the received first sensor data, and transmits them to the signal line DOUTP via the host interface 133 as a low-accuracy first physical quantity PLP1 with a predetermined sensitivity and a low-accuracy second physical quantity PLP2 with a predetermined sensitivity. In addition, the processing circuit 130 replaces the low-precision third physical quantity PLP3 of a predetermined sensitivity obtained by performing the above-mentioned arithmetic processing on the low-precision third physical quantity LP3 among the received first sensor data with the high-precision third physical quantity PHP3 of a predetermined sensitivity obtained by performing the above-mentioned arithmetic processing, and transmits it to the signal line DOUTP via the host interface 133.

[0053] Furthermore, for example, the first sensor 110 may be a six-axis sensor. A six-axis sensor is, for example, a combination of a three-axis physical quantity sensor capable of independently detecting physical quantities in the X-axis, Y-axis, and Z-axis directions and a three-axis physical quantity sensor capable of independently detecting physical quantities in the X-axis, Y-axis, and Z-axis directions. For example, if the first sensor 110 is a combination of a three-axis acceleration sensor and a three-axis angular velocity sensor, the first sensor 110 detects a low-precision first angular velocity LG1, a low-precision second angular velocity LG2, a low-precision third angular velocity LG3, a low-precision first acceleration LA1, a low-precision second acceleration LA2, and a low-precision third acceleration LA3, each having a first sensitivity. For example, if the angular velocity in the Z direction needs to be more accurate than the low-precision third angular velocity LG3, the inertial sensor module 100 uses the second sensor 120 as a Z-axis angular velocity sensor to acquire a high-precision third angular velocity HG3 having a second sensitivity. Then, by applying the above-mentioned method, the host interface 133 may transmit a low-precision first angular velocity PLG1, a low-precision second angular velocity PLG2, a high-precision third angular velocity PHG3, a low-precision first acceleration PLA1, a low-precision second acceleration PLA2, and a low-precision third acceleration PLA3, each having a predetermined sensitivity, to the host 200. Note that a sensor unit consisting of an acceleration sensor and an angular velocity sensor may be called an IMU (Inertial Measurement Unit).

[0054] Here, using FIGS. 11 and 12 , an example will be described in which higher accuracy of the angular velocity along the third detection axis is required than that along the first and second detection axes. As described above, the host 200 including the first sensor 110 and the inertial sensor module 100 is included in a measurement system. The measurement system is fixedly mounted on the aforementioned moving body. FIG. 11 is a diagram illustrating the relationship between the moving direction of a four-wheeled automobile, which is an example of the aforementioned moving body, and the coordinate systems of the first sensor 110 and the second sensor 120 included in the measurement system. Hereinafter, the coordinate systems of the first sensor 110 and the second sensor 120 will be simply referred to as sensor coordinate systems. It is also assumed that the X-, Y-, and Z-axes of the coordinate system of the first sensor 110 and the coordinate system of the second sensor 120 are aligned. The X-axis of the sensor coordinate system corresponds to the front-to-rear direction of the moving body, with the forward direction being the positive X-axis direction. The Y-axis of the sensor coordinate system corresponds to the left-to-right direction of the moving body, with the rightward direction being the positive Y-axis direction. The Z axis of the sensor coordinate system is perpendicular to the X and Y axes, and the downward direction of the moving body is the positive Z axis direction. Because the moving body moves on a substantially horizontal plane, the XY plane is the moving body's plane of movement, and the positive Z axis direction can be considered to coincide with the direction of gravity. The attitude of the moving body is expressed by a roll angle around the X axis, a pitch angle around the Y axis, and a yaw angle around the Z axis. As described above, because the moving body moves on a substantially horizontal plane, the roll angle, which is an attitude, corresponds to the moving body's left-right tilt, the pitch angle corresponds to the moving body's forward-backward tilt, and the yaw angle corresponds to the moving body's change of direction or orientation. In inertial navigation calculations, the attitude is calculated by time-integrating the angular velocity, which is the output signal of the first sensor 110, etc. In other words, in FIG. 11, if the first sensor 110 and the second sensor 120 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 over time.

[0055] FIG. 12 is a diagram illustrating a position error. FIG. 12 shows a bird's-eye view of the moving object from above, i.e., an XY plane view in the sensor coordinate system. The actual moving direction is indicated by a solid line as the original moving direction. Because the forward direction of the moving object is the positive direction of the X axis, the actual moving direction is also the positive direction of the X axis. The position shown in B1 is the position of the moving object at the first time t1 and is assumed to be known. The position shown in B2 is the actual position of the moving object at the second time t2, and the position shown in B3 is the position calculated by inertial navigation calculation using the measurement system and is assumed to be the position of the moving object at the second time t2. The distance between the positions shown in B2 and B3 is the position error caused by a bias error in the output signal of the first sensor 110 while the moving object moves from the first time t1 to the second time t2. As described above, since the moving object moves on a substantially horizontal plane, this positional deviation is caused by an error in the yaw angle, which is its attitude. This yaw angle error increases over time. As described above, it is desirable that the error in the yaw angle be smaller than the error in the roll angle and the error in the pitch angle. In other words, it is desirable that the measurement accuracy of the angular velocity around the Z axis be higher than the measurement accuracy of the angular velocity around the X axis and the measurement accuracy of the angular velocity around the Y axis. In this regard, by applying the method of this embodiment, the measurement system can acquire the yaw angle based on the high-precision third physical quantity HP3 with a predetermined sensitivity. This allows the position of a moving object, etc. to be predicted more appropriately.

[0056] Note that configuring a six-axis sensor using the aforementioned Si-MEMS inertial sensor can achieve miniaturization, but it is not possible to obtain sensor data with sufficient accuracy to meet the requirements described above in FIG. 10 and other figures. On the other hand, configuring first sensor 110 so that it can acquire the six physical quantities using only the aforementioned quartz inertial sensor can obtain highly accurate sensor data, but it is not possible to achieve miniaturization. Therefore, in this embodiment, first sensor 110, which is a compact six-axis sensor, may be configured using an Si-MEMS inertial sensor, and second sensor 120 may be configured as a quartz inertial sensor to acquire physical quantities only in directions requiring high accuracy. In this way, a physical quantity sensor that achieves both miniaturization and high accuracy can be realized.

[0057] Although the above description has been given for the case where the third detection axis is the Z axis, the X axis may also be the third detection axis. In this case, the Y axis may be the first detection axis and the Z axis may be the second detection axis, or the Z axis may be the first detection axis and the Y axis may be the second detection axis. Similarly, the Y axis may also be the third detection axis. In this case, the X axis may be the first detection axis and the Z axis may be the second detection axis, or the Z axis may be the first detection axis and the X axis may be the second detection axis.

[0058] As described above, the inertial sensor module of this embodiment includes a first sensor, a second sensor, and a processing circuit. The first sensor detects a first physical quantity on a first detection axis and a second physical quantity on a second detection axis with a first sensitivity. The second sensor detects a third physical quantity on a third detection axis with a second sensitivity different from the first sensitivity and with higher accuracy than the first sensor. The processing circuit converts the first physical quantity and the second physical quantity with the first sensitivity and the third physical quantity with the second sensitivity into the first physical quantity, the second physical quantity, and the third physical quantity with a predetermined sensitivity.

[0059] In this way, a device that requires the first physical quantity, the second physical quantity, and the third physical quantity can receive predetermined sensor data unified to a predetermined sensitivity without having to adjust the sensitivity to be unified.

[0060] The device may also include a first interface that is an interface with the first sensor, a second interface that is an interface with the second sensor, and a host interface that is an interface with the host, and the host interface may output the first physical quantity, the second physical quantity, and the third physical quantity with a predetermined sensitivity to the host.

[0061] In this way, data can be transmitted and received between the first sensor, the second sensor, and the host. The host interface can also output sensor data with a unified sensitivity to the host.

[0062] Furthermore, the first sensor may input a first physical quantity and a second physical quantity having a first sensitivity to a first interface at a first input rate, and the second sensor may input a third physical quantity having a second sensitivity to a second interface at a second input rate that is different from the first input rate.

[0063] In this way, even if sensors with different input rates are included, sensor data with uniform sensitivity can be output to the host.

[0064] The host interface may also output the first physical quantity, the second physical quantity, and the third physical quantity with a predetermined sensitivity to the host at a predetermined output rate.

[0065] In this way, even if sensors with different input rates are included, sensor data with a unified output rate and sensitivity can be output to the host.

[0066] Additionally, the rate of the predetermined output rate may be lower than the rate of the first input rate and the rate of the second input rate.

[0067] In this way, the first sensor data and the second sensor data on the input side can be output in synchronization.

[0068] In addition, the first sensor may detect a low-accuracy third physical quantity around the third detection axis, the second sensor may detect a high-accuracy third physical quantity around the third detection axis, and the processing circuit may output the high-accuracy third physical quantity input via the second interface to the host via the host interface instead of the low-accuracy third physical quantity input via the first interface.

[0069] In this way, it is possible to output sensor data with a uniform predetermined sensitivity and high accuracy in any axis.

[0070] Furthermore, the first physical quantity may be an angular velocity about a first detection axis, the second physical quantity may be an angular velocity about a second detection axis, and the third physical quantity may be an angular velocity about a third detection axis.

[0071] In this way, angular velocity data with uniform sensitivity can be output.

[0072] Furthermore, the first physical quantity may be acceleration on a first detection axis, the second physical quantity may be acceleration on a second detection axis, and the third physical quantity may be acceleration on a third detection axis.

[0073] In this way, acceleration data with uniform sensitivity can be output.

[0074] Although the present embodiment has been described in detail above, it will be readily apparent to those skilled in the art that many modifications are possible without substantially departing from the novel features and advantages of the present disclosure. Therefore, all such modifications are intended to be included within the scope of the present disclosure. For example, a term described at least once in the specification or drawings together with a different term having a broader or equivalent meaning may be replaced with that different term anywhere in the specification or drawings. Furthermore, all combinations of the present embodiment and modifications are also included within the scope of the present disclosure. Furthermore, the configuration and operation of the inertial sensor module are not limited to those described in the present embodiment, and various modifications are possible. [Explanation of symbols]

[0075] 100...inertial sensor module, 110...first sensor, 120...second sensor, 130...processing circuit, 131...first interface, 132...second interface, 133...host interface, 200...host, A1...first acceleration, A2...second acceleration, A3...third acceleration, CS1...signal line (signal), CLK1...signal line (signal), DIN1...signal line, DOUT1...signal line, CS2...signal line (signal), CLK2...signal line (signal), DIN2...signal line, DOUT2...signal line, CSP...signal Line (signal), CLKP...signal line (signal), DINP...signal line, DOUTP...signal line, DRDY1...signal line (signal), DRDYP...signal line (signal), G1...first angular velocity, G2...second angular velocity, G3...third angular velocity, HP3...high precision third physical quantity, LA1...low Accuracy first acceleration, LA2...Low precision second acceleration, LA3...Low precision third acceleration, LG1...Low precision first angular velocity, LG2...Low precision second angular velocity, LG3...Low precision third angular velocity, LP1...Low precision first physical quantity, LP2...Low precision second physical quantity, LP3...Low precision third physical quantity, P1...first physical quantity, P2...second physical quantity, P3...third physical quantity, PA1...first acceleration with predetermined sensitivity, PA2...second acceleration with predetermined sensitivity, PA3...third acceleration with predetermined sensitivity, PG1...first angular velocity with predetermined sensitivity, PG2...second angular velocity with predetermined sensitivity, PG3...third angular velocity with predetermined sensitivity, PP1...first physical quantity with predetermined sensitivity, PP2...second physical quantity with predetermined sensitivity, PP3...third physical quantity with predetermined sensitivity, PLP1...low-precision first physical quantity with predetermined sensitivity, PLP2...low-precision second physical quantity with predetermined sensitivity, PLP3...low-precision third physical quantity with predetermined sensitivity, PHP1 ...precise third physical quantity with specified sensitivity, PLA1...low-precise first acceleration with specified sensitivity, PLA2...low-precise second acceleration with specified sensitivity, PLA3...low-precise third acceleration with specified sensitivity, PLG1...low-precise first angular velocity with specified sensitivity, PLG2...low-precise second acceleration with specified sensitivity, PLH3...high-precise third acceleration with specified sensitivity, SF...scale factor, SF1, SF11, SF12...first scale factor, SFP1...first scale factor (precise scale factor), SF2, SF21, SF22...second scale factor

Claims

1. a first sensor that detects a first physical quantity on a first detection axis and a second physical quantity on a second detection axis with a first sensitivity; a second sensor that detects a third physical quantity on a third detection axis with higher accuracy than the first sensor and with a second sensitivity different from the first sensitivity; a processing circuit that performs processing to convert the first physical quantity and the second physical quantity of the first sensitivity and the third physical quantity of the second sensitivity into the first physical quantity, the second physical quantity, and the third physical quantity of a predetermined sensitivity; An inertial sensor module comprising:

2. 2. The inertial sensor module according to claim 1, a first interface that interfaces with the first sensor; a second interface that interfaces with the second sensor; a host interface that is an interface with a host; Including, The host interface an inertial sensor module configured to output the first physical quantity, the second physical quantity, and the third physical quantity with the predetermined sensitivity to the host;

3. 3. The inertial sensor module according to claim 2, the first sensor inputs the first physical quantity and the second physical quantity having the first sensitivity to the first interface at a first input rate; The inertial sensor module is characterized in that the second sensor inputs the third physical quantity having the second sensitivity to the second interface at a second input rate that is different from the first input rate.

4. 4. The inertial sensor module according to claim 3, The host interface an inertial sensor module configured to output the first physical quantity, the second physical quantity, and the third physical quantity of the predetermined sensitivity to the host at a predetermined output rate;

5. 5. The inertial sensor module according to claim 4, The rate of the predetermined output rate is: The inertial sensor module has a rate lower than the first input rate and the second input rate.

6. 6. The inertial sensor module according to claim 2, The first sensor is Detecting a low-accuracy third physical quantity around the third detection axis; The second sensor is Detecting a high-precision third physical quantity around the third detection axis; The processing circuitry an inertial sensor module that outputs a high-precision third physical quantity input via the second interface to the host via the host interface, instead of the low-precision third physical quantity input via the first interface.

7. 7. The inertial sensor module according to claim 1, the first physical quantity is an angular velocity around the first detection axis, the second physical quantity is an angular velocity around the second detection axis, The inertial sensor module, wherein the third physical quantity is an angular velocity around the third detection axis.

8. 7. The inertial sensor module according to claim 1, the first physical quantity is acceleration in the first detection axis, the second physical quantity is acceleration in the second detection axis, The inertial sensor module, wherein the third physical quantity is acceleration on the third detection axis.

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