Sensor and calibration device

Abstract

To provide a sensor and a calibration device with which it is possible to commonize a power supply between a circuit using a high voltage and a circuit for which application of a high voltage should be avoided, with a simple configuration.SOLUTION: The sensor comprises: a power supply terminal; a first and a second circuit which share the power supply supplied via the power supply terminal from the outside; a switching element; and a sensor signal output terminal for outputting to the outside a sensor signal having been controlled to within a prescribed voltage range. The first circuit is supplied with said power supply via the switching element, and the second circuit includes a high voltage operating circuit that operates with a power supply voltage that is a higher voltage than the permitted power supply voltage of the first circuit. The switching element turns on when the voltage of the sensor signal output terminal is within the voltage range and turns off when the voltage of the sensor signal output terminal is controlled from the outside so as to be out of the voltage range.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to sensors and calibration devices.

Background Art

[0002] Patent Document 1 describes an example of a protection circuit for stopping power output in the event of an abnormality in power output.

[0003] Patent Document 2 describes a configuration example of a magnetic sensor using a Hall IC (Integrated Circuit). In the magnetic sensor described in Patent Document 2, the following configuration prevents a high voltage applied to the power supply during programming of the Hall IC from being applied to other circuits connected to the common power supply line. That is, the magnetic sensor described in Patent Document 2 is assembled with the power supply line connected to the Hall IC and the power supply line connected to other circuits separated using two pads. Next, during programming of the Hall IC, a high voltage is applied only to the Hall IC using a program terminal. Then, after programming, the two pads are connected.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] The protection circuit that shuts down the power supply during circuit protection described in Patent Document 1 has a problem that it cannot be used for the purpose of protecting other circuits during programming described in Patent Document 2. On the other hand, in the configuration described in Patent Document 2, there are problems such as the need for a terminal for applying a high voltage other than the power supply terminal, or the need for processes such as soldering after applying the high voltage. When resin-molding the substrate, processes such as soldering need to be performed before molding. Therefore, resin molding will be performed after calibration, but there is a possibility that the positions of the substrate and the hole IC may change before and after the process of curing the resin molding, resulting in a problem of reduced accuracy.

[0006] The present disclosure has been made in view of the above circumstances, and an object thereof is to provide a sensor and a calibration device that can share the power supplies of a circuit using a high voltage and a circuit to which a high voltage is not to be applied with a simple configuration.

Means for Solving the Problems

[0007] One aspect of the present disclosure includes a power supply terminal, a first circuit and a second circuit that share the power supply supplied from the outside via the power supply terminal, a switching element, and a sensor signal output terminal that outputs a sensor signal controlled within a predetermined voltage range to the outside. The power supply is supplied to the first circuit via the switching element. The second circuit includes a high-voltage operation circuit that operates at a power supply voltage higher than the allowable power supply voltage of the first circuit. The switching element is a sensor that turns on when the voltage of the sensor signal output terminal is within the voltage range and turns off when the voltage of the sensor signal output terminal is controlled outside the voltage range from the outside.

[0008] Another aspect of the present disclosure includes a power supply terminal, a first circuit and a second circuit that share a power supply externally supplied via the power supply terminal, a switching element, and a sensor signal output terminal that outputs a sensor signal controlled within a predetermined voltage range to the outside. The power supply is supplied to the first circuit via the switching element. The second circuit includes a high-voltage operation circuit that operates at a power supply voltage higher than the allowable power supply voltage of the first circuit. The switching element is connected to a sensor that turns on when the voltage of the sensor signal output terminal is within the voltage range and turns off when the voltage of the sensor signal output terminal is controlled from the outside to be outside the voltage range. The calibration device controls the voltage of the sensor signal output terminal to be outside the voltage range and supplies the high voltage to the power supply terminal to operate the high-voltage operation circuit.

Advantages of the Invention

[0009] According to each aspect of the present disclosure, the power supplies of a circuit using a high voltage and a circuit to which a high voltage is not to be applied can be shared with a simple configuration.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In each figure, the same or corresponding configurations are denoted by the same reference numerals or reference numerals with an English letter appended at the end, and the description will be appropriately omitted.

[0012] [First Embodiment] FIG. 1 is a block diagram showing a configuration example of a sensor and a calibration device according to a first embodiment of the present disclosure. FIG. 10 is a schematic diagram for explaining an attachment example of the sensor according to the first embodiment of the present disclosure. FIG. 11 is a block diagram showing a configuration example of the sensor during normal use according to the first embodiment of the present disclosure. FIG. 2 is a perspective view showing an external configuration example of the sensor according to the first embodiment of the present disclosure. FIG. 3 is a schematic diagram showing a cross-sectional configuration example of the sensor according to the first embodiment of the present disclosure. FIG. 4 is a schematic diagram showing a planar configuration example of a substrate according to the first embodiment of the present disclosure. FIG. 5 is a schematic diagram showing a configuration example of a connector according to the first embodiment of the present disclosure. FIGS. 6 to 9 are schematic diagrams for explaining an operation example of the sensor according to the first embodiment of the present disclosure. FIG. 12 is a flowchart showing an operation example of the calibration device according to the first embodiment of the present disclosure. FIG. 13 is a schematic diagram for explaining another operation example of the sensor according to the first embodiment of the present disclosure.

[0013] (Mechanical Configuration of Sensor) The sensor 10 shown in FIG. 1 is attached to the hydraulic pump 61 shown in FIG. 10 and is configured as a detection device for detecting the angle of the swash plate of the hydraulic pump 61 and the vibration generated in the hydraulic pump 61. However, the sensor 10 is not limited to a detection device for detecting the angle of the swash plate of the hydraulic pump 61 and vibration, and the detection target (physical quantity to be detected) and the number of detection targets are arbitrary.

[0014] The hydraulic pump 61 shown in FIG. 10 has a swash plate (not shown), and is a variable displacement type hydraulic pump whose discharge capacity is changed by changing the tilt angle of the swash plate (hereinafter simply referred to as "angle"). A servo piston 62 is connected to the swash plate (not shown), and the angle of the swash plate is changed by driving the servo piston 62. Thereby, the discharge capacity of the hydraulic pump 61 is controlled. The hydraulic pressure for driving the servo piston 62 is controlled by a servo valve (not shown). The angle of the swash plate is detected by a sensor 10. As shown in FIG. 10, the servo piston 62 moves in the axial direction (see arrow A1) by the hydraulic pressure supplied from the servo valve. A rocker cam 63 is connected to the servo piston 62, and the rocker cam 63 rotates as the servo piston 62 moves in the axial direction. A swash plate is connected to the rocker cam 63, and the angle of the swash plate is changed as the rocker cam 63 rotates.

[0015] The sensor 10 has a spool 42 which is a movable member provided so as to be movable in the radial direction of the servo piston 62 (see arrow A0). A ball 42-1 is rotatably provided at the tip of the spool 42. An inclined surface 62a inclined with respect to the axial direction is provided on the outer peripheral surface of the servo piston 62, and the ball 42-1 of the spool 42 is arranged to contact the inclined surface 62a. Therefore, when the servo piston 62 moves in the axial direction, the spool 42 moves in the radial direction of the servo piston 62. The position of the spool 42 corresponds to the position of the servo piston 62, that is, the angle of the swash plate, and the sensor 10 detects the angle of the swash plate by detecting the position of the spool 42. The controller 70 shown in FIG. 11 includes a processor P1 such as a CPU (Central Processing Unit), an A / D converter (analog / digital converter) AD1 that converts an analog signal representing the angle of the swash plate of the hydraulic pump 61 detected by the sensor 10 and an analog signal representing the vibration generated in the hydraulic pump 61 into a digital signal, etc. As a functional configuration composed of a combination of such hardware and software such as a program executed by the processor P1, it has a vibration monitoring unit 71 that monitors vibration. The angle of the swash plate detected by the sensor 10 is input to the controller 70, and the vibration detected by the sensor 10 is input to the vibration monitoring unit 71. The vibration monitoring unit 71 performs frequency analysis on the vibration detected by the sensor 10 and detects a failure of the hydraulic pump 61. The controller 70 may have a pump control unit 72 that controls the hydraulic pump 61.

[0016] As shown in FIGS. 2 and 3, the sensor 10 includes a connector 3 for electrically connecting to the outside and a spool 42. As shown in FIG. 3, the spool 42 includes the ball 42-1 as described above and moves in the direction of arrow A0 using a spring 43. Further, the spool 42 includes a magnet 44. Further, the sensor 10 includes a substrate 41 shown in FIGS. 3 and 4. The substrate 41 mounts the electronic circuit shown in FIG. 1.

[0017] (Electrical Configuration of Sensor) As shown in FIG. 1, the sensor 10 includes, as components of an electronic circuit, a first circuit 1, a second circuit 2, an output limiting circuit 12, a connector 3, a switching element TR1, Zener diodes ZD1 and ZD2, and a resistor R1. The first circuit includes a sensor element 11. The second circuit includes a Hall IC 13. As shown in FIGS. 1 and 5, the connector 3 has four terminals T1, T2, T3, and T4. FIG. 5 is a schematic view of the connector 3 as seen from the direction of arrow A10 shown in FIG. 2. Terminal T1 is a power supply terminal (positive power supply terminal). Terminal T2 is the first output terminal of the sensor signal (sensor signal output terminal). Terminal T3 is a power supply terminal (negative power supply terminal (GND (ground) terminal)). Terminal T4 is the second output terminal of the sensor signal (second sensor signal output terminal). Note that the voltage or signal of terminal T1 is denoted as Vsup, the signal of terminal T2 as Sig1, the voltage or signal of terminal T3 as GND, and the signal of terminal T4 as Sig2. Also, the switching element TR1 is an n-type MOSFET (Metal Oxide Semiconductor Field-Effect Transistor).

[0018] The sensor element 11 is, for example, an acceleration sensor IC that operates on a single power supply of 5V DC. The sensor element 11 includes, for example, an acceleration sensor composed of MEMS (Micro Electro Mechanical Systems). As shown in FIG. 6, for example, with 1 / 2 of the power supply voltage being 0 [G], a voltage signal corresponding to the vibration acceleration [G] in the direction of arrow A0 is output from the terminal O. FIG. 6 is an example of characteristics when the power supply voltage of the sensor element 11 is 5V (GND voltage: 0V). The positive power supply terminal V of the sensor element 11 is connected to the terminal T1. The ground terminal (negative power supply terminal) G of the sensor element 11 is connected to the drain of the switching element TR1 and the anode of the zener diode ZD1. The output terminal O of the sensor element 11 is connected to the input terminal I of the output limiting circuit 12. In this configuration, when the switching element TR1 is on, a power supply voltage is applied between the power supply terminal V and the ground terminal G of the sensor element 11 (power is supplied to the sensor element 11), and when the switching element TR1 is off, the power supply voltage is no longer applied between the power supply terminal V and the ground terminal G of the sensor element 11 (power is no longer supplied to the sensor element 11). Note that the sensor element 11 is not limited to a single IC, and may be a discrete circuit combining a plurality of ICs or single elements. In this embodiment, it is assumed that the absolute maximum rating of the power supply voltage of the sensor element 11 is, for example, 5.5V. Also, in the present disclosure, the allowable power supply voltage of the first circuit 1 is the absolute maximum rating of the power supply voltage of the sensor element 11, or a value having a certain margin with respect to the absolute maximum rating of the power supply voltage of the sensor element 11 (a value lower than the absolute maximum rating of the power supply voltage by a predetermined value).

[0019] The output limiting circuit 12 is, for example, an analog IC that operates with a single power supply of 5V DC. The output limiting circuit 12 is a circuit that performs analog absolute value processing. It receives the output signal of the sensor element 11 shown in FIG. 6 and outputs, as shown in FIG. 7, a voltage signal having a value obtained by adding 1 / 2 of the power supply voltage to the absolute value of (input voltage - 1 / 2 of the power supply voltage) from terminal O. FIG. 7 is an example of the characteristics when the power supply voltage of the output limiting circuit 12 is 5V (GND voltage: 0V) and the output characteristics of the sensor element 11 are those shown in FIG. 6. In this case, the output limiting circuit 12 outputs an externally controlled sensor signal (output signal of the sensor element 11) within a predetermined voltage range (a range of 1 / 2 or more of the power supply voltage to the power supply voltage) via terminal T2. The positive power supply terminal V of the output limiting circuit 12 is connected to terminal T1. The ground terminal (negative power supply terminal) G of the output limiting circuit 12 is connected to terminal T3. The output terminal O of the output limiting circuit 12 is connected to terminal T2 via resistor R1 (the output terminal O is connected to one terminal of resistor R1, and the other terminal of resistor R1 is connected to terminal T2). Note that the output limiting circuit 12 may be not limited to an IC, but may also be a discrete circuit combining a plurality of ICs or single elements.

[0020] The Hall IC 13 includes, inside, an EEPROM (electrically erasable and programmable read-only memory) 14 which is a configuration example of a non-volatile memory, a Hall element (second sensor element) as a magnetic sensor not shown in the figure, and a signal processing circuit that processes the output signal of the Hall element based on calibration data (stored content) stored in the EEPROM 14. For example, as shown in FIG. 8, it outputs a voltage signal corresponding to the stroke [mm] of the spool 42 (displacement in the direction of arrow A0) from the output terminal O (second sensor signal output terminal). In the characteristic shown in FIG. 8, the reference stroke is set to 0 [mm], the output voltage at 0 [mm] is set to 1 / 2 of the power supply voltage, and the difference value from 1 / 2 of the power supply voltage of the output voltage increases according to the positive and negative displacements from the reference stroke. FIG. 8 is an example of the characteristic when the power supply voltage of the Hall IC 13 is 5V (GND voltage: 0V). The Hall IC 13 is mounted on the substrate 41 so as to face the magnet 44 provided in the spool 42, and by detecting the magnetic field generated by the magnet 44, it outputs a signal corresponding to the stroke (position) of the spool 42. The positive power supply terminal V of the Hall IC 13 is connected to the terminal T1. The ground terminal (negative power supply terminal) G of the Hall IC 13 is connected to the terminal T3. The output terminal O of the Hall IC 13 is connected to the terminal T4.

[0021] Also, the Hall IC 13 has a function of writing calibration data to the EEPROM 14 by externally inputting a predetermined signal to the positive power supply terminal V. When a signal of a predetermined pattern is externally input to the positive power supply terminal V of the Hall IC 13, the input data is temporarily stored in an internal volatile memory, and when a high voltage for data writing (for example, 12.5V) is applied to the positive power supply terminal V, the temporarily stored data is written to and stored in the EEPROM 14.

[0022] Hereinafter, the operation state of writing calibration data to the EEOROM 14 is referred to as the Hall IC calibration time, and the operation state in which the normal power supply voltage (set to DC 5V) is supplied to the terminal T1 instead of the Hall IC calibration time is referred to as the normal use time.

[0023] The switching element TR1 has its drain connected to the ground terminal G of the sensor element 11 and the anode of the Zener diode ZD1 as described above, its source connected to the terminal T3, and its gate connected to the terminal T2. The switching element TR1 has operating characteristics as shown in, for example, Fig. 9, where a drain-source current flows when the gate voltage is between 2.5 V and 5 V, and no drain-source current flows when the gate voltage is 0 V. As shown in Fig. 7, the output limiting circuit 12 outputs a voltage having a value equal to or greater than half of the power supply voltage during normal use. The output voltage of this output limiting circuit 12 is applied to the gate of the switching element TR1 via the resistor R1. Therefore, the switching element TR1 is always on during normal use. On the other hand, when the terminals T2 and T3 are short-circuited (or connected with a resistance value sufficiently low with respect to the resistor R1), the gate voltage becomes 0 V (or approximately 0 V), and the switching element TR1 turns off.

[0024] Also, the Zener diodes ZD1 and ZD2 are provided as a protection circuit and have a Zener voltage greater than the power supply voltage of 5 V during normal operation. The Zener diode ZD1 has its anode connected to the ground terminal G of the sensor element 11 and its cathode connected to the terminal T1. The Zener diode ZD2 has its anode connected to the terminal T3 and its cathode connected to the terminal T2.

[0025] (Operation example of the sensor) After manufacture, during Hall IC calibration, the sensor 10 is connected to the calibration device 50, the spool 42 is actually moved, the output signal of the Hall IC 13 is measured, and calibration data is written to the EEPROM 14 based on the measurement result. At that time, a high voltage for data writing (for example, 12.5 V) is applied between the terminals T1 and T3 for a predetermined period. When the calibration device 50 applies a high voltage for data writing between the terminals T1 and T3, it shorts the terminals T2 and T3. When the terminals T2 and T3 are short-circuited, the switching element TR1 turns off, and no power is supplied to the sensor element 11. Therefore, a voltage exceeding the allowable power supply voltage is not applied to the sensor element 11 (the first circuit 1).

[0026] On the one hand, when it is attached to and used with the hydraulic pump 61 (during normal use), the sensor 10 is connected to a predetermined one or more controllers, and the power supply voltage during normal use is applied between the terminal T1 and the terminal T3. In this case, the switching element TR1 is always on, and power is always supplied to the sensor element 11.

[0027] (Configuration of the calibration device) The calibration device 50 shown in FIG. 1 includes a predetermined jig (not shown), and the sensor 10 fixed to the jig is electrically connected via the connector 3 (connected to the terminals T1 to T4), and is a device for writing calibration data to the EEPROM 14 of the sensor 10 and the like. The calibration device 50 includes a control unit 51, a power supply unit 52, a switch 53, a drive unit 54, and an actuator 55.

[0028] The control unit 51 is composed of a computer such as a microcomputer or a personal computer, peripheral circuits, peripheral devices, etc., and controls each part according to a predetermined instruction operation by the operator. The control unit 51, for example, inputs the signal of the terminal T2 and monitors the output signal of the output limit circuit 12. Also, the control unit 51, for example, inputs the signal of the terminal T4 and monitors the output signal of the Hall IC 13. Also, the control unit 51 inputs the signal of the terminal T4 during Hall IC calibration and monitors the response signal from the Hall IC 13. Also, the control unit 51 turns on the switch 53 during Hall IC calibration to short-circuit between the terminal T2 and the terminal T3 (ground). Also, the control unit 51 controls the actuator 55 via the drive unit 54 to change the stroke of the spool 42. Also, the control unit 51 controls the output voltage of the power supply unit 52.

[0029] The power supply unit 52 switches the power supply voltage during normal use (for example, 5V) and the high voltage used during Hall IC calibration (for example, 12.5V) according to the instruction of the control unit 51 and outputs it to the terminal T1, or changes the voltage value in a predetermined pattern based on the communication specification of the Hall IC 13 and outputs it to the terminal T1 to transmit data to the Hall IC 13.

[0030] The switch 53 is a switch such as a semiconductor switch or an electromagnetic relay, with one end connected to the terminal T2 and the other end connected to the terminal T3 (ground). The switch 53 short - circuits or opens the connection between the terminal T2 and the terminal T3 according to the instruction of the control unit 51.

[0031] The drive unit 54 drives the actuator 55 according to the instruction of the control unit 51. The actuator 55 has a telescopic part 56, and changes the position of the spool 42 by expanding and contracting the telescopic part 56 in the direction of the arrow A0.

[0032] Note that in FIG. 1, the combination of the sensor 10 and the calibration device 50 constitutes the calibration system 100.

[0033] (Operation example of the calibration device) Next, with reference to FIG. 12, the flow of the calibration process using the calibration device 50 will be described. In the process shown in FIG. 12, first, the operator connects the sensor 10 to the calibration device 50 (S11). When a predetermined start operation is performed, the calibration device 50 (control unit 51) sets the power supply voltage Vsup to 5V (specified value) (S12). At this time, the calibration device 50 opens the connection between Sig1 and GND (S13). Next, the calibration device 50 moves the spool 42 of the sensor 10 to the position A (extended position) (S14). Next, the calibration device 50 measures the Sig2 voltage and stores it in the variable Va (S15). Next, the calibration device 50 moves the spool 42 of the sensor 10 to the position B (contracted position) (S16). Next, the calibration device 50 measures the Sig2 voltage and stores it in the variable Vb (S17). Next, the calibration device 50 calculates the calibration parameters based on the target voltages given in advance at positions A and B and Va and Vb (S18). Next, the calibration device 50 short - circuits the connection between Sig1 and GND (S19). Next, the calibration device 50 transmits the calibration parameters from Vsup and Sig2 (S20). Next, the calibration device 50 applies a voltage of 12.5V for EEPROM writing to Vsup (S21). Next, the calibration device 50 changes the position of the spool 42 of the sensor 10, evaluates the relationship between Sig2 and the stroke (S22), and ends the process.

[0034] (Operation and Effect of the First Embodiment) According to the first embodiment, the power supplies of a circuit (second circuit 2) that uses a high voltage and a circuit (first circuit 1) to which a high voltage is not to be applied can be shared with a simple configuration.

[0035] (Modification Example of the First Embodiment) FIG. 13 shows another example of the output characteristics of the output limiting circuit 12. FIG. 13 shows an example of the relationship between the input signal (output signal of the sensor element 11) of the output limiting circuit 12 and the output signal of the output limiting circuit 12. The horizontal axis represents the vibration acceleration, and the vertical axis represents the voltage. In the example shown in FIG. 13, the output signal of the output limiting circuit 12 is limited to 1 / 2 or more of the power supply voltage by offsetting the input signal by a predetermined value and suppressing the change rate of the output signal. In this case, the information on the positive and negative of the vibration acceleration can be maintained.

[0036] [Second Embodiment] FIG. 14 is a block diagram showing a configuration example of a sensor and a calibration device according to the second embodiment of the present disclosure. The second embodiment is a configuration corresponding to the switching element TR1 of the first embodiment, in which the switching element TR1a is changed to a p-type MOSFET, and the main change is the point provided between the positive power supply terminal V of the sensor element 11 and the terminal T1. In the second embodiment, the calibration system 100a includes a sensor 10a and a calibration device 50a.

[0037] In sensor 10a, the drain of switching element TR1a is connected to the positive power supply terminal V of sensor element 11, the source is connected to terminal T1, and the gate is connected to terminal T2. Also, the anode of Zener diode ZD1a corresponding to Zener diode ZD1 is connected to terminal T3, and the cathode is connected to the positive power supply terminal V of sensor element 11. Further, output limiting circuit 12a corresponding to output limiting circuit 12 is a circuit that performs analog absolute value processing, and outputs, from terminal O, a voltage signal of a value obtained by subtracting the absolute value of (input voltage - half of the power supply voltage) from half of the power supply voltage. In this case, output limiting circuit 12a outputs, to the outside via terminal T2, a sensor signal (output signal of sensor element 11) controlled within a predetermined voltage range (a range of half of the power supply voltage or less and ground voltage or more).

[0038] Output limiting circuit 12a outputs a voltage having a value of half of the power supply voltage or less during normal use. The output voltage of this output limiting circuit 12a is applied to the gate of switching element TR1a via resistor R1. Therefore, switching element TR1a is always on during normal use. On the other hand, when terminals T1 and T2 are short-circuited (or connected with a resistance value sufficiently low with respect to resistor R1), the gate voltage becomes 0V (or approximately 0V), and switching element TR1a turns off.

[0039] On the other hand, in calibration device 50a, switch 53a corresponding to switch 53 connects between terminals T1 and T2, and is controlled to be on or off by control unit 51a corresponding to control unit 51.

[0040] In the above configuration, after manufacturing, during the Hall IC calibration, the sensor 10a is connected to the calibration device 50a, the spool 42 is actually moved, the output signal of the Hall IC 13 is measured, and calibration data is written to the EEPROM 14 based on the measurement result. At this time, a high voltage for data writing (for example, 12.5 V) is applied between the terminal T1 and the terminal T3 for a predetermined period. When the calibration device 50a applies a high voltage for data writing between the terminal T1 and the terminal T3, the terminal T1 and the terminal T2 are short-circuited. When the terminal T1 and the terminal T2 are short-circuited, the switching element TR1a is turned off, and the sensor element 11 is not supplied with power. Therefore, a voltage exceeding the allowable power supply voltage is not applied to the sensor element 11 (the first circuit 1).

[0041] According to the second embodiment, similar to the first embodiment, the power supplies of the circuit using a high voltage (the second circuit 2) and the circuit to which a high voltage is not to be applied (the first circuit 1) can be shared with a simple configuration.

[0042] [Third Embodiment] FIG. 15 is a block diagram showing a configuration example of a sensor and a calibration device according to the third embodiment of the present disclosure. The third embodiment is different from the first embodiment in that the second circuit 2b for the second circuit 2 in the first embodiment is changed to a circuit that stores calibration data using fuses F1 to F3 instead of the Hall IC 13. The second circuit 2b includes fuses F1 to F3 and Zener diodes ZD3 to ZD5 (high voltage operation circuit). Also, in the connector 3b corresponding to the connector 3, the terminal T4 is not used (or omitted). The first circuit 1b corresponding to the first circuit 1 includes a sensor element 11b corresponding to the sensor element 11. The sensor element 11b newly includes a plurality of setting terminals S, and calibrates output characteristics and the like according to whether the setting terminals S are short-circuited to the ground.

[0043] Fuses F1 to F3 and Zener diodes ZD3 to ZD5 are each connected in series. One terminal of each of fuses F1 to F3 is connected to terminal T3, and the cathodes of Zener diodes ZD3 to ZD5 are connected to terminal T1. The other terminals of fuses F1 to F3 and the anodes of Zener diodes ZD3 to ZD5 are connected to each one of a plurality of terminals S. The Zener voltages of Zener diodes ZD3 to ZD5 are higher than the normal power supply voltage and are different from each other.

[0044] When a voltage exceeding the Zener voltage of Zener diodes ZD3 to ZD5 is applied between terminal T1 and terminal T3, the second circuit 2b blows fuses F1 to F3.

[0045] On the other hand, a calibration device 50b corresponding to the calibration device 50 includes a control unit 51b having a configuration corresponding to the control unit 51, a power supply unit 52b having a configuration corresponding to the power supply unit 52, and a switch 53. The power supply unit 52b switches and outputs a normal voltage and each voltage for blowing fuses F1 to F3. The control unit 51b measures the output signal Sig1 of the sensor element 11b, for example, by applying a predetermined vibration or the like, determines fuses F1 to F3 to be blown based on the measurement result, and causes the power supply unit 52 to output a high voltage necessary for blowing in a state where the switch 53 is turned on.

[0046] According to the third embodiment, similarly to the first and second embodiments, the power supplies of a circuit using a high voltage (second circuit 2b) and a circuit to which a high voltage is not to be applied (first circuit 1b) can be shared with a simple configuration.

[0047] [Aspects of Each Embodiment] The first aspect includes power supply terminals (T1, T3), a first circuit (1, 1b) and a second circuit (2, 2b) that share the power supply supplied externally via the power supply terminals, switching elements (TR1, TR1a), and a sensor signal output terminal (T2) that outputs a sensor signal controlled within a predetermined voltage range (equal to or higher than half of the power supply voltage or equal to or lower than half of the power supply voltage) to the outside. The power supply is supplied to the first circuit via the switching element. The second circuit includes a high-voltage operation circuit (EEPROM14, Zener diodes ZD4 to ZD6, and fuses F1 to F3) that operates at a power supply voltage higher than the allowable power supply voltage of the first circuit. The switching element is a sensor that turns on when the voltage of the sensor signal output terminal is within the voltage range and turns off when the voltage of the sensor signal output terminal is controlled from the outside to be outside the voltage range.

[0048] The second aspect is a sensor in which the first circuit includes a sensor element (11, 11b), and further includes an output limiting circuit (12) that limits the output signal of the sensor element within the voltage range and outputs it to the sensor signal output terminal.

[0049] The third aspect further includes a second sensor signal output terminal (T4). The high-voltage operation circuit is a non-volatile memory (EEPROM13). The second circuit includes a second sensor element (a hall element not shown in the hall IC13). The sensor processes the output signal of the second sensor element based on the stored content of the non-volatile memory and outputs it to the second sensor signal output terminal.

[0050] The fourth aspect is a calibration device (50, 50a, 50b) that is connected to the sensor of the first aspect, controls the voltage of the sensor signal output terminal to be outside the voltage range, and supplies the high voltage to the power supply terminal to operate the high-voltage operation circuit.

[0051] The fifth aspect is a calibration device in which the high-voltage operation circuit is a non-volatile memory.

[0052] As described above, the embodiments of the present invention have been described with reference to the drawings. However, the specific configuration is not limited to the above embodiments, and design changes and the like within the scope not departing from the gist of the present invention are also included.

[0053] For example, when the negative power supply terminal (ground terminal) sets the metal housing of the sensor 10 to the ground potential, the terminal T3 of the connector 3 may be omitted and used as the housing ground. Also, in the configuration shown in FIG. 1, for example, a sensor element 11 and an output limiting circuit are provided in the first circuit 1 so that the power can be turned on or off by the switching element TR1, and when the terminals T2 and T3 are not short-circuited, a circuit may be added to apply an on voltage to the gate of the switching element TR1 using the voltage of the terminal T1.

Explanation of Reference Numerals

[0054] 1, 1b... First circuit, 2, 2b... Second circuit, 10, 10a, 10b... Sensors, 11, 11b... Sensor elements, 13... Hall IC, 14... EEPROM, 50, 50a, 50b... Measuring devices, TR1, TR1a... Switching elements, T1... Terminal (power supply terminal), T2... Terminal (sensor signal output terminal), T3... Terminal (power supply terminal), T4... Terminal (second sensor signal output terminal)

Claims

1. A power supply terminal, a first circuit and a second circuit that share a power supply supplied from the outside via the power supply terminal, a switching element, a sensor signal output terminal that outputs, to the outside, a sensor signal of a sensor element included in the first circuit, the sensor signal being controlled within a predetermined voltage range, comprising: the power supply is supplied to the first circuit via the switching element, the second circuit includes a high-voltage operation circuit that operates at a power supply voltage higher than the allowable power supply voltage of the first circuit, the switching element turns on when the voltage of the sensor signal output terminal is within the voltage range, and turns off when the voltage of the sensor signal output terminal is controlled from the outside to be outside the voltage range, when the high-voltage power supply voltage is supplied from the power supply terminal to operate the high-voltage operation circuit, the voltage of the sensor signal output terminal is controlled from the outside to be outside the voltage range, and the switching element turns off, so that the high-voltage power supply voltage is not supplied to the first circuit, a sensor.

2. The sensor according to claim 1, further comprising an output limiting circuit that limits an output signal of the sensor element within the voltage range and outputs the signal to the sensor signal output terminal. The sensor according to claim 1.

3. further comprising a second sensor signal output terminal, the high-voltage operation circuit is a non-volatile memory, the second circuit includes a second sensor element, and processes an output signal of the second sensor element based on stored content of the non-volatile memory and outputs the signal to the second sensor signal output terminal, The sensor according to claim 1 or 2.

4. A power supply terminal, a first circuit and a second circuit that share a power supply supplied from the outside via the power supply terminal, a switching element, a sensor signal output terminal that outputs, to the outside, a sensor signal of a sensor element included in the first circuit, the sensor signal being controlled within a predetermined voltage range, comprising: the power supply is supplied to the first circuit via the switching element, the second circuit includes a high-voltage operation circuit that operates at a power supply voltage higher than the allowable power supply voltage of the first circuit, the switching element turns on when the voltage of the sensor signal output terminal is within the voltage range, and turns off when the voltage of the sensor signal output terminal is controlled from the outside to be outside the voltage range, connected to the sensor When supplying the high-voltage power supply voltage from the power supply terminal to operate the high-voltage operation circuit, the voltage of the sensor signal output terminal is controlled outside the voltage range to turn off the switching element, so that the high-voltage power supply voltage is not supplied to the first circuit. Calibration device.

5. The high-voltage operation circuit is a non-volatile memory. The calibration device according to claim 4.

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