ANGLE DETECTION DEVICE, MOTOR DEVICE AND LOGIC SIGNAL GENERATOR

Abstract

An angle detection device comprises an angle sensor configured to detect a rotating magnetic field that changes periodically in response to a rotation angle of a motor, and outputs a first detection signal and a second detection signal with a phase difference whose value is not an integer multiple of 90°, and a logic signal generation section configured to generate a first logic signal using the first detection signal, generate a second logic signal with a phase different from that of the first logic signal using the second detection signal, and generate a third logic signal with a phase different from that of the first and second logic signals using the first and second logic signals.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention

[0001] The present invention relates to an angle detection device configured to detect the rotation angle of a motor, a motor device including a motor and the angle detection device, and a logic signal generator. 2. Description of the state of the art

[0002] A brushless motor (also called a brushless DC motor) uses an angle detector to detect its rotation angle. Common examples of angle detectors include a detector that uses a magnetic detection element, such as a Hall element, and an optical detector that uses light. The detection signal from the angle detector is used to control the rotation angle and / or rotation speed of the brushless motor.

[0003] A brushless motor is typically a three-phase motor driven by a three-phase AC voltage. A three-phase motor comprises a plurality of coils that are controlled to apply the voltages at different times. If the three-phase motor includes three coils, the voltage application times can be controlled with three logic signals (signals each indicating two states, "high" and "low") with 120° different phases. The detection signal of the angle detector is used to generate the three logic signals.

[0004] JP S60-134792 A discloses a drive device that generates control signals for exciting the three-phase coils of a motor from a three-phase sinusoidal signal obtained from a magnetic sensor element. EP 2546611 A1 discloses that a magnetic sensor including three magnetic detection elements with 60°-shifted sensitivity axis directions and configured to output three-phase output signals is applied to the rotation control of a brushless motor. EP 2843825 A1 discloses a motor control device that controls the three-phase drive power by using an angle detection output signal approximating a linear function, which is generated from four detection output signals obtained from the output signals of two magnetic detection sections.

[0005] DE 19619806 A1 discloses a sensor device including a bridge circuit. The bridge circuit includes a pair of magnetoresistive sensor elements with bias layer sections whose magnetization directions are parallel to a reference line and antiparallel to each other, and another magnetoresistive sensor element with a bias layer section whose magnetization direction forms an angle of 45° with the reference line.

[0006] To reduce the cost of a brushless motor driver circuit, the driver circuit configuration is simplified as desired. However, conventional methods have had the problem that the overall cost of the driver circuit is difficult to reduce due to the complicated configuration of the angle detector and the logic signal generator, which generates a plurality of logic signals from the angle detector's detection signal. SUMMARY OF THE INVENTION

[0007] The object of the present invention is to provide a simply constructed angle detection device for use for a drive circuit of a motor device, a motor device including the angle detection device, and a logic signal generator used for the angle detection device.

[0008] An angle detection device according to the present invention is used for a driving circuit for a motor.The angle detection device according to the present invention includes an angle sensor configured to detect a physical quantity that periodically changes in response to a rotation angle of the motor, and output a first detection signal and a second detection signal having a phase difference whose value is not an integer multiple of 90°, and a logic signal generating section configured to generate a first logic signal using the first detection signal, generate a second logic signal having a phase different from that of the first logic signal using the second detection signal, and generate a third logic signal having a phase different from those of the first and second logic signals using the first and second detection signals.

[0009] A motor device according to the present invention includes the angle detection device and the motor according to the present invention.

[0010] A logic signal generator according to the present invention is configured to generate three logic signals, each with different phases. The logic signal generator according to one embodiment of the method is configured to receive a first detection signal and a second detection signal with a phase difference whose value is not an integer multiple of 90°, generate and output a first logic signal using the first detection signal, generate and output a second logic signal with a phase different from that of the first logic signal using the second detection signal, and generate and output a third logic signal with a phase different from that of the first and second logic signals using the first and second detection signals.

[0011] According to one embodiment of the present invention, the first to third logic signals, each with a different phase, are generated using the first and second detection signals with a phase difference whose value is not an integer multiple of 90°. According to one embodiment of the present invention, a simply constructed angle detection device can thus be realized.

[0012] Other and further objects, features and advantages of the present invention will be set forth more fully in the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments and, together with the description, serve to explain the principles of the technology. Fig. 1 is an explanatory diagram showing a configuration of a motor device according to a first embodiment of the invention. Fig. 2 is an explanatory diagram showing the interior of an angle detection device according to the first embodiment of the invention. Fig. 3 is a circuit diagram showing a circuit configuration of the angle detection device according to the first embodiment of the invention. Fig. 4 is an explanatory diagram showing the definitions of directions and angles in the first embodiment of the invention. Fig. 5 is a perspective view showing a part of a resistor portion in the first embodiment of the invention. Fig. 6 is a waveform diagram showing the waveform of each of the first and second detection signals in the first embodiment of the invention. Fig. 7 is a timing chart showing the first to third logic signals in the first embodiment of the invention. Fig. 8 is an explanatory diagram for describing an action of an angle sensor in the first embodiment of the invention. Fig. 9 is an explanatory diagram showing a configuration of a motor device according to a second embodiment of the invention. Fig. 10 is a characteristic diagram showing a relationship between the rotation angle of a motor and the angle of a rotating magnetic field in the second embodiment of the invention. Fig. 11 is a waveform diagram showing the waveform of each of the first and second detection signals in a comparative example. Fig. 12 is a timing chart showing the first to third logic signals of the comparative example. Fig. 13 is a waveform diagram showing the waveform of each of the first and second detection signals in the second embodiment of the invention. Fig. 14 is a timing chart showing the first to third logic signals in the second embodiment of the invention. Fig. 15 is an explanatory diagram showing the angle detecting device according to a third embodiment of the invention. Fig. 16 is an explanatory diagram showing the interior of a first electronic component in a fourth embodiment of the invention. Fig. 17 is an explanatory diagram showing the interior of a second electronic component in the fourth embodiment of the invention. Fig. 18 is a circuit diagram showing a circuit configuration of an angle sensor in a fifth embodiment of the invention. Fig. 19 is an explanatory diagram showing a first example of a configuration of an angle detection device according to the fifth embodiment of the invention. Fig. 20 is an explanatory diagram showing a second example of the configuration of the angle detection device according to the fifth embodiment of the invention. Fig. 21 is a circuit diagram showing a circuit configuration of an angle detecting apparatus according to a sixth embodiment of the invention. Fig. 22 is a waveform diagram showing the waveform of each of the first and second detection signals in the sixth embodiment of the invention. Fig. 23 is a timing chart showing the first to third logic signals in the sixth embodiment of the invention. Fig. 24 is a circuit diagram showing a circuit configuration of an angle detection device according to a seventh embodiment of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] In the following, some exemplary embodiments and modification examples of the technology will be described in detail with reference to the accompanying drawings. It should be noted that the following description refers to illustrative examples of the disclosure and should not be construed as limiting the technology. Factors including, without limitation, numerical values, shapes, materials, components, positions of the components, and the manner in which the components are connected to each other are only illustrative and should not be construed as limiting the technology. Furthermore, elements in the following exemplary embodiments that are not recited in any of the broadest independent claims of the disclosure are optional and may be provided as needed. The drawings are schematic and not to be considered as being to scale.Similar elements are designated by the same reference numbers to avoid redundant descriptions. Please note that the description is given in the following order. [First embodiment]

[0015] A schematic structure of a motor device according to a first embodiment of the present invention will first be described with reference to Fig. 1 described. Fig. 1 is an explanatory diagram showing a configuration of a motor device 100 according to the present embodiment.

[0016] The motor device 100 according to the present embodiment includes an angle detection device 1 according to the present embodiment, a motor 110, and a drive circuit 120 for driving the motor 110. The motor 110 is, for example, a three-phase brushless motor (also referred to as a brushless DC motor). The following description will be given for the case where the motor 110 is, for example, a three-phase brushless motor. In such a case, the motor 110 includes a shaft (not shown) configured to rotate about a rotation axis C, a rotor 111 fixed to the shaft (not shown), a stator 112, and a plurality of coils.

[0017] Fig. 1 shows an example in which the stator 112 has three slots. In this example, the motor 110 includes a first coil 113u, a second coil 113v, and a third coil 113w as a plurality of coils. The first coil 113u, the second coil 113v, and the third coil 113w are also referred to as U-phase coils, V-phase coils, and W-phase coils, respectively. The first coil 113u, the second coil 113v, and the third coil 113w are arranged at intervals of 120° around the rotation axis C.

[0018] The rotor 111 is formed by a magnetic field generator 5, which generates a magnetic field. The magnetic field generator 5 corresponds to a "magnetic field generation section" within the scope of the present invention. Fig. 1 shows a cylindrical magnet as an example of the magnetic field generator 5. This magnet is a bipolar magnet with an N-pole and an S-pole, which are arranged symmetrically around an imaginary plane in which the rotation axis C lies.

[0019] The number of slots of the stator 112 is not limited to three, but may also be more than three, for example, six or nine. Likewise, the number of poles of the magnetic field generator 5 is not limited to two. The magnetic field generator 5 may be a multi-pole magnet, such as a four- or eight-pole magnet.

[0020] The direction of the magnetic field generated by the magnetic field generator 5 rotates with the rotation of the motor 110, ie, with the rotation of the shaft (not shown). The magnetic field generated by the magnetic field generator 5 is referred to below as the rotating magnetic field MF. The rotating magnetic field MF is Fig. 4 and will be described later. The angle detection device 1 is configured to detect the rotating magnetic field MF and generate three logic signals to be used to control the timing of the voltage applied to the first to third coils 113u, 113v, and 113w. Specifically, in the present embodiment, the angle detection device 1 is arranged on the rotation axis C and opposite an end face of the magnetic field generator 5. The structure of the angle detection device 1 will be described in detail later.

[0021] The driver circuit 120 includes a control circuit 121 and an output circuit 122. The control circuit 121 is configured to receive the three logic signals generated by the angle detection device 1 and an external speed command Sc. The control circuit 121 controls the output circuit 122 based on the three logic signals and the speed command Sc. The output circuit 122 applies a voltage to each of the first to third coils 113u, 113v, and 113w based on the commands from the control circuit 121.

[0022] The output circuit 122 includes six switching elements (not shown). Each of the six switching elements includes, for example, a transistor. The control circuit 121 turns the six switching elements on and off, thereby controlling the timing of voltage application to each of the first to third coils 113u, 113v, and 113w, so that a magnetic field in which the magnetic fields generated by the first to third coils 113u, 113v, and 113w are combined rotates (hereinafter referred to as a composite magnetic field). The timing is controlled based on the three logic signals. The rotor 111 rotates due to the interaction of the magnetic field generated by the magnetic field generator 5 (rotating magnetic field MF) and the composite magnetic field.

[0023] The control circuit 121 compares the speed command Sc and the speed of the motor 110 obtained from the three logic signals and controls the output circuit 122 so that the speed of the motor 110 follows the speed command Sc.

[0024] The angle detection device 1 is described below using the Fig. 2 and Fig. 3 described in more detail. Fig. 2 is an explanatory diagram showing the interior of the angle detection device 1. Fig. 3 is a circuit diagram showing a circuit configuration of the angle detection device 1.

[0025] First, the structure of the angle detection device 1 is outlined. The angle detection device 1 is used, as described above, for the drive circuit 120 for the motor 110. The angle detection device 1 includes an angle sensor 10 and a logic signal generating section 20. The angle sensor 10 and the logic signal generating section 20 can each be formed as a single chip with a rectangular solid shape. The chip including the angle sensor 10 is referred to below as the first chip 2. The chip including the logic signal generating section 20 is referred to as the second chip 3. The angle detection device 1 includes the first chip 2 and the second chip 3.

[0026] As in Fig. As shown in FIG. 2, one of the first and second chips 2 and 3 is mounted on the other of the first and second chips 2 and 3. The angle detection device 1 further includes a substrate 4. Specifically, in the present embodiment, the second chip 3 is mounted on the substrate 4, and the first chip 2 is mounted on the second chip 3.

[0027] The angle detection device 1 further includes a plurality of wires 41 connecting the first chip 2 and the second chip 3, a plurality of leads 43, a plurality of wires 42 connecting the second chip 3 and the plurality of leads 43, and a sealing resin 44 sealing the first chip 2 and the second chip 3.

[0028] Next, a configuration of the angle sensor 10 will be described. The angle sensor 10 is configured to detect a physical quantity that periodically changes in response to the rotation angle of the motor 110 and output a first detection signal S1 and a second detection signal S2 with a phase difference whose value is not an integer multiple of 90°. In the present embodiment, the physical quantity is the rotating magnetic field MF generated by the magnetic field generator 5. The direction of the rotating magnetic field MF rotates with the rotation angle of the motor 110.

[0029] The definitions of directions and angles in the present embodiment will now be explained with reference to the Fig. 1, Fig. 2 and Fig. 4 described. Fig. Figure 4 is an explanatory diagram illustrating the definitions of directions and angles in the present embodiment. First, a direction parallel to the rotation axis C is Fig. 1 is defined as the Z direction. In Fig. 2, the Z-direction is shown as an upward direction. As in Fig. As shown in Figure 2, the first chip 2 (angle sensor 10) and the second chip 3 (logic signal generating section 20) are stacked in the Z direction. Subsequently, two directions perpendicular to the Z direction and orthogonal to each other are defined as the X direction and the Y direction. Fig. 2 and Fig. 4, the X-direction is shown as a direction to the right. In Fig. 2, the Y-direction is defined as a direction from the near to the far side of Fig. 2. In Fig. In Figure 4, the Y direction is shown as the upward direction. The direction opposite the X direction is defined as the -X direction, the direction opposite the Y direction as the -Y direction, and the direction opposite the Z direction as the -Z direction.

[0030] In Fig. 4, the symbol PL denotes an imaginary plane perpendicular to the rotation axis C. This imaginary plane is hereinafter referred to as the reference plane PL. In the present embodiment, the angle sensor 10 is configured to detect the components of the rotating magnetic field MF in directions parallel to the reference plane PL at a reference position PR within the reference plane PL. In the following description, the direction of the rotating magnetic field MF refers to the direction within the reference plane PL. The reference position PR may be the position where the reference plane PL and the rotation axis C intersect.

[0031] In Fig. 4, the direction of the rotating magnetic field MF is represented by the arrow with the symbol MF. In the present embodiment, the direction of the rotating magnetic field MF is expressed as an angle (hereinafter referred to as the rotating magnetic field angle) θ formed with a reference magnetic field direction DR. The reference magnetic field direction DR is the X direction. The direction of the rotating magnetic field MF rotates in Fig. 4 counterclockwise. The angle of the rotating magnetic field θ is represented by a positive value when viewed counterclockwise from the reference magnetic field direction DR, and by a negative value when viewed clockwise from the reference magnetic field direction DR.

[0032] The angle sensor 10 includes a power supply terminal 10a, a ground terminal 10b, a first output terminal 10c, a second output terminal 10d, a first resistance portion 11, a second resistance portion 12, a third resistance portion 13, a fourth resistance portion 14, and a plurality of magnetic detection elements constituting the first to fourth resistance portions 11 to 14. Each of the plurality of magnetic detection elements is configured to detect the rotating magnetic field MF.

[0033] As in Fig. 3, the first resistance portion 11 is provided between the power supply terminal 10a and the first output terminal 10c in a circuit configuration. The second resistance portion 12 is provided between the ground terminal 10b and the first output terminal 10c in the circuit configuration. The third resistance portion 13 is provided between the power supply terminal 10a and the second output terminal 10d in the circuit configuration. The fourth resistance portion 14 is provided between the ground terminal 10b and the second output terminal 10d in the circuit configuration. In the present application, the term "in a circuit configuration" is used to indicate a layout in a circuit diagram, rather than a layout in a physical configuration.

[0034] A voltage or current of a specific magnitude is applied to the power supply terminal 10a. The ground terminal 10b is connected to ground.

[0035] The first output terminal 10c outputs a signal corresponding to the potential at the junction point of the first resistance section 11 and the second resistance section 12 as the first detection signal S1. The second output terminal 10d outputs a signal corresponding to the potential at the junction point of the third resistance section 13 and the fourth resistance section 14 as the second detection signal S2.

[0036] The plurality of magnetic detection elements will now be described. Each of the plurality of magnetic detection elements may be a magnetoresistive element. The magnetoresistive element may be a tunneling magnetoresistive (TMR) element, a giant magnetoresistive (GMR) element, or an anisotropic magnetoresistive (AMR) element. Alternatively, each of the plurality of magnetic detection elements may be a non-magnetoresistive element that detects a magnetic field, such as a Hall element.

[0037] In the present embodiment, each of the plurality of magnetic detection elements is a spin-valve magnetoresistive element (hereinafter referred to as an "MR element"). The spin-valve MR element includes a magnetization-pinned layer having a first magnetization whose direction is fixed, a free layer having a second magnetization whose direction is variable depending on the rotating magnetic field MF, and an intermediate layer located between the magnetization-pinned layer and the free layer. The spin-valve MR element can be a TMR element or a GMR element. The intermediate layer of the TMR element is a tunnel barrier layer. The intermediate layer of the GMR element is a non-magnetic conductive layer.The resistance of the spin-valve MR element varies depending on the angle formed by the second magnetization direction of the free layer with the first magnetization direction of the magnetization-pinned layer, and has a minimum resistance when the aforementioned angle is 0° and a maximum resistance when the aforementioned angle is 180°. In . Fig. 3, the filled arrows indicate the magnetization directions of the magnetization-pinned layers of the MR elements.

[0038] Fig. 5 is a perspective view showing a part of one of the first to fourth resistor sections 11 to 14. The resistor section includes a plurality of lower electrodes 61, a plurality of MR elements 50, and a plurality of upper electrodes 62. The plurality of lower electrodes 61 are arranged on a substrate (not shown). Each lower electrode 61 has a long, slender shape. A gap is provided between two longitudinally adjacent lower electrodes 61. As shown in Fig. 5, the MR elements 50 are located near the two longitudinal ends of the upper surface of each lower electrode 61. Each MR element 50 includes an antiferromagnetic layer 51, a magnetization-pinned layer 52, an intermediate layer 53, and a free layer 54, which are stacked in this order from the lower electrode 61 side. The antiferromagnetic layer 51 is electrically connected to the lower electrode 61. The antiferromagnetic layer 51 is made of an antiferromagnetic material. The antiferromagnetic layer 51 is in exchange coupling with the magnetization-pinned layer 52, thereby fixing the magnetization direction of the magnetization-pinned layer 52. The plurality of upper electrodes 62 are arranged on the plurality of MR elements 50.Each upper electrode 62 has a long, slender shape and electrically connects the free layers 54 of two adjacent MR elements 50 arranged on two longitudinally adjacent lower electrodes 61. In such a configuration, the electrode shown in . Fig. 5, the resistance section includes the plurality of MR elements 50 connected in series by the plurality of lower electrodes 61 and the plurality of upper electrodes 62.

[0039] The magnetization-pinned layer 52 may be a so-called self-pinned layer (synthetic ferri-pinned layer, SFP layer). The self-pinned layer has a stacked ferri-structure in which a ferromagnetic layer, a non-magnetic intermediate layer, and a ferromagnetic layer are stacked, and the two ferromagnetic layers are antiferromagnetically coupled. In a case where the magnetization-pinned layer 52 is the self-pinned layer, the antiferromagnetic layer 51 may be omitted.

[0040] The layers 51 to 54 of each MR element 50 can be arranged in a Fig. 5 be stacked in reverse order.

[0041] Next, the direction of the first magnetization of the magnetization-pinned layers 52 in each of the first to fourth resistance sections 11 to 14 is determined with reference to the Fig. 3 and Fig. 4. In Fig. 4, symbol D1 indicates a first reference direction parallel to the sensitivity axis of each of the first and second resistance sections 11 and 12. Specifically, in the present embodiment, the first reference direction D1 is a reference direction for the direction of the first magnetization of the magnetization-pinned layer 52 in each of the plurality of MR elements 50 of the first and second resistance sections 11 and 12. Symbol D2 indicates a second reference direction parallel to the sensitivity axis of each of the third and fourth resistance sections 13 and 14. Specifically, in the present embodiment, the second reference direction D2 is a reference direction for the direction of the first magnetization of the magnetization-pinned layer 52 in each of the plurality of MR elements 50 of the third and fourth resistance sections 13 and 14.

[0042] In the present embodiment, the first reference direction D1 and the second reference direction D2 satisfy the following first requirement: The direction of the rotating magnetic field MF detected by each of the plurality of MR elements 50 of the first and second resistance sections 11 and 12 at a predetermined time when the rotating magnetic field MF periodically changes is referred to as a first magnetic field direction. The direction of the rotating magnetic field MF detected by each of the plurality of MR elements 50 of the third and fourth resistance sections 13 and 14 at the same predetermined time is referred to as a second magnetic field direction. The first requirement is that the difference between an angle that the first magnetic field direction forms with the first reference direction D1 and an angle that the second magnetic field direction forms with the second reference direction D2 is an angle that is not an integer multiple of 90°.

[0043] In the present embodiment, the first reference direction D1 and the second reference direction D2 further satisfy the following second requirement: The second requirement is that an angle formed between the first reference direction D1 and the second reference direction D2 is not an integer multiple of 90°.

[0044] Specifically, in the present embodiment, the first reference direction D1 is the Y direction. The second reference direction D2 is a direction rotated 60° from the Y direction (first reference direction D1) to the -X direction. In this case, the difference between the angle formed by the first magnetic field direction with the first reference direction D1 and the angle formed by the second magnetic field direction with the second reference direction D2 is 60°. The angle formed between the first reference direction D1 and the second reference direction D2 is also 60°.

[0045] The first magnetization of the magnetization-pinned layer 52 in each of the plurality of MR elements 50 of the first resistance section 11 includes a component in the first reference direction D1 (Y direction). The first magnetization of the magnetization-pinned layer 52 in each of the plurality of MR elements 50 of the second resistance section 12 includes a component in the direction opposite to the first reference direction D1 (-Y direction).

[0046] The first magnetization of the magnetization-pinned layer 52 in each of the plurality of MR elements 50 of the third resistance section 13 includes a component in the second reference direction D2. The first magnetization of the magnetization-pinned layer 52 in each of the plurality of MR elements 50 of the fourth resistance section 14 includes a component in the direction opposite to the second reference direction D2.

[0047] If the first magnetization of the magnetization-pinned layer 52 includes a component in a specific reference direction, the component in the specific reference direction may be the main component of the first magnetization of the magnetization-pinned layer 52. Alternatively, the first magnetization of the magnetization-pinned layer 52 may be free of a component in a direction orthogonal to the specific reference direction. In the present embodiment, if the first magnetization of the magnetization-pinned layer 52 includes a component in the specific reference direction, the direction of the first magnetization of the magnetization-pinned layer 52 is equal to or substantially equal to the specific reference direction.

[0048] Next, the first detection signal S1 and the second detection signal S2 will be described. In the angle sensor 10, the potential at the connection point of the first resistance section 11 and the second resistance section 12 changes with the strength of a component (hereinafter referred to as the first component) of the rotating magnetic field MF in a direction parallel to the first reference direction D1. The angle sensor 10 thus detects the strength of the first component and outputs a signal indicative of the strength as the first detection signal S1. The first detection signal S1 has a correspondence with the strength of the first component. The strength of the first component has a correspondence with the angle of the rotating magnetic field θ (see Fig. 4). The strength of the first component can be represented by a positive value if the direction of the first component coincides with the first reference direction D1, and by a negative value if the direction of the first component coincides with the direction opposite to the first reference direction D1.

[0049] In the angle sensor 10, the potential at the connection point of the third resistance section 13 and the fourth resistance section 14 changes with the strength of a component (hereinafter referred to as the second component) of the rotating magnetic field MF in a direction parallel to the second reference direction D2. The angle sensor 10 thus detects the strength of the second component and outputs a signal indicating the strength as a second detection signal S2. The second detection signal S2 has a correspondence with the strength of the second component. The strength of the second component has a correspondence with the angle of the rotating magnetic field θ (see Fig. 4). The strength of the second component may be represented by a positive value if the direction of the second component coincides with the second reference direction D2, and by a negative value if the direction of the second component coincides with the direction opposite to the second reference direction D2.

[0050] Fig. Fig. 6 is a waveform diagram showing the waveform of each of the first and second detection signals S1 and S2. In Fig. In Figure 6, the horizontal axis shows the rotation angle θM of the motor 110, and the vertical axis shows the magnitude of the signals. The vertical axis is expressed in arbitrary units. In the present embodiment, the value of the rotation angle θM is the same as, or substantially the same as, the angle of the rotating magnetic field θ.

[0051] As in Fig. As shown in Figure 6, in the present embodiment, the phase difference between the first detection signal S1 and the second detection signal S2 is 60°. In other words, in the present embodiment, the angle formed between the first reference direction D1 and the second reference direction D2 is the same as the angle corresponding to the phase difference between the first detection signal S1 and the second detection signal S2.

[0052] Next, a configuration of the logic signal generating section 20 will be described. The logic signal generating section 20 is configured to receive the first detection signal S1 and the second detection signal S2, generate and output a first logic signal Su using the first detection signal S1, generate and output a second logic signal Sv having a phase different from that of the first logic signal Su using the second detection signal S2, and generate and output a third logic signal Sw having a phase different from those of the first and second logic signals Su and Sv using the first and second detection signals S1 and S2.

[0053] The logic signal generation section 20 can be implemented, for example, by an application-specific integrated circuit (ASIC). The logic signal generation section 20, which, like the logic signal generation section 20 implemented by an ASIC, can be implemented as a chip, is also referred to as a "logic signal generator."

[0054] The logic signal generating section 20 includes a power supply terminal 20a, a ground terminal 20b, a first input terminal 20c, a second input terminal 20d, a first output terminal 20e, a second output terminal 20f, a third output terminal 20g, a first comparator 21, a second comparator 22, a third comparator 23, and two resistors 24 and 25. The first comparator 21 includes a first input port 21a, a second input port 21b, and an output port 21c. The second comparator 22 has a first input port 22a, a second input port 22b, and an output port 22c. The third comparator 23 has a first input port 23a, a second input port 23b, and an output port 23c.

[0055] One end of resistor 24 is connected to the power supply terminal 20a. One end of resistor 25 is connected to the other end of resistor 24. The other end of resistor 25 is connected to the ground terminal 20b. A voltage of a certain magnitude is applied to the power supply terminal 20a. The ground terminal 20b is grounded.

[0056] The first input port 21a of the first comparator 21 and the first input port 23a of the third comparator 23 are connected to the first input terminal 20c. The first input port 22a of the second comparator 22 and the second input port 23b of the third comparator 23 are connected to the second input terminal 20d. The second input port 21b of the first comparator 21 and the second input port 22b of the second comparator 22 are connected to the connection point of the resistors 24 and 25.

[0057] The first output terminal 10c of the angle sensor 10 is connected to the first input terminal 20c of the logic signal generating section 20. The first output terminal 10c is thus connected via the first input terminal 20c to the first input port 21a of the first comparator 21 and the first input port 23a of the third comparator 23. The second output terminal 10d of the angle sensor 10 is connected to the second input terminal 20d of the logic signal generating section 20. The second output terminal 10d is connected via the second input terminal 20d to the first input port 22a of the second comparator 22 and the second input port 23b of the third comparator 23.

[0058] The output port 21c of the first comparator 21 is connected to the first output terminal 20e. The first output terminal 20e outputs the signal output from the output port 21c of the first comparator 21 as the first logic signal Su.

[0059] The output terminal 22c of the second comparator 22 is connected to the second output terminal 20f. The second output terminal 20f outputs the signal output from the output port 22c of the second comparator 22 as the second logic signal Sv.

[0060] The output port 23c of the third comparator 23 is connected to the third output terminal 20g. The third output terminal 20g outputs the signal output from the output port 23c of the third comparator 23 as the third logic signal Sw.

[0061] Next, the first to third logic signals Su, Sv and Sw are calculated with reference to the Fig. 6 and Fig. 7 described. Fig. Figure 7 is a timing chart showing the first to third logic signals Su, Sv and Sw.

[0062] First, the first logic signal Su will be described. The first detection signal S1 is input to the first input port 21a of the first comparator 21. A reference voltage with a magnitude leading to a value of 0 on the vertical axis of Fig. 6, is input to the second input port 21b of the first comparator 21. The first comparator 21 compares the value of the first detection signal S1 with that of the reference voltage and outputs the first logic signal Su. As shown in Fig. 6, the value of the first detection signal S1 is greater than that of the reference voltage (0 on the vertical axis of Fig. 6) when the rotation angle θM is greater than 0° and less than 180°. The value of the first detection signal S1 is smaller than that of the reference voltage (0 on the vertical axis of Fig. 6) when the rotation angle θM is greater than 180° and less than 360°. Thus, the first comparator 21 outputs a high-level signal when the rotation angle θM is greater than 0° and less than 180°, and outputs a low-level signal when the rotation angle θM is greater than 180° and less than 360°.

[0063] Next, the second logic signal Sv will be described. The second detection signal S2 is input to the first input port 22a of the second comparator 22. The reference voltage with the magnitude corresponding to the value 0 on the vertical axis of Fig. 6, is input to the second input port 22b of the second comparator 22. The second comparator 22 compares the value of the second detection signal S2 with that of the reference voltage and outputs the second logic signal Sv. As shown in Fig. 6, the value of the second detection signal S2 is greater than that of the reference voltage (0 on the vertical axis of Fig. 6) when the rotation angle θM is greater than 60° and less than 240°. The value of the second detection signal S2 is smaller than that of the reference voltage (0 on the vertical axis of Fig. 6) when the rotation angle θM is greater than or equal to 0° and less than 60°, or greater than 240° and less than or equal to 360°. The second comparator 22 thus outputs a high-level signal when the rotation angle θM is greater than 60° and less than 240°, and outputs a low-level signal when the rotation angle θM is greater than or equal to 0° and less than 60°, or greater than 240° and less than or equal to 360°.

[0064] Next, the third logic signal Sw will be described. The first detection signal S1 is input to the first input port 23a of the third comparator 23. The second detection signal S2 is input to the second input port 23b of the third comparator 23. The third comparator 23 compares the value of the first detection signal S1 with the value of the second detection signal S2 and outputs the third logic signal Sw. As shown in Fig. As shown in Figure 6, the value of the first detection signal S1 is greater than that of the second detection signal S2 when the rotation angle θM is greater than or equal to 0° and less than 120°, or greater than 300° and less than or equal to 360°. The value of the first detection signal S1 is smaller than that of the second detection signal S2 when the rotation angle θM is greater than 120° and less than 300°. Thus, the third comparator 23 outputs a high-level signal when the rotation angle θM is greater than or equal to 0° and less than 120°, or greater than 300° and less than or equal to 360°, and outputs a low-level signal when the rotation angle θM is greater than 120° and less than 300°.

[0065] In the present embodiment, the control circuit 121 detects the rotation angle θM using the first to third logic signals Su, Sv, and Sw. Specifically, when the first to third logic signals Su, Sv, and Sw are at the high level, the low level, and the high level, respectively, the control circuit 121 determines that the rotation angle θM is in the range of 0° to 60°. When the first to third logic signals Su, Sv, and Sw are at the high level, the high level, and the high level, respectively, the control circuit 121 determines that the rotation angle θM is in the range of 60° to 120°. In this way, the control circuit 121 detects the rotation angle θM in units of 60° (every 1 / 6 of a turn) depending on the combination of the levels of the first to third logic signals Su, Sv, and Sw.

[0066] In the present embodiment, the phase difference between the first logic signal Su and the second logic signal Sv is 60°. The phase difference between the first logic signal Su and the third logic signal Sw is 60°. The phase difference between the second logic signal Sv and the third logic signal Sw is 120°.

[0067] Next, a method for manufacturing the angle sensor 10 will be briefly described. The method for manufacturing the angle sensor 10 includes the step of forming the plurality of MR elements 50, the step of forming the power supply terminal 10a, the ground terminal 10b, the first output terminal 10c, and the second output terminal 10d, and the step of forming a plurality of wiring pieces that connect the plurality of MR elements 50 to the power supply terminal 10a, the ground terminal 10b, the first output terminal 10c, and the second output terminal 10d.

[0068] In the step of forming the plurality of first MR elements 50, a plurality of initial MR elements are first formed, which later become the plurality of MR elements 50. Each of the plurality of initial MR elements includes at least one initial magnetization-pinned layer, which later becomes the magnetization-pinned layer 52, as well as the free layer 54 and the intermediate layer 53.

[0069] Next, the magnetization directions of the initially magnetization-pinned layers are fixed in the aforementioned predetermined directions using laser light and external magnetic fields. For example, the plurality of initial MR elements, which will later become the plurality of MR elements 50 of the first resistance section 11, are irradiated with the laser light while applying an external magnetic field in the first reference direction D1 (Y direction). When the laser light irradiation is completed, the magnetization directions of the initially magnetization-pinned layers are fixed in the first reference direction D1. The initially magnetization-pinned layers thereby become the magnetization-pinned layers 52, and the plurality of initial MR elements become the plurality of MR elements 50 of the first resistance section 11.

[0070] For another plurality of initial MR elements, which will later become the plurality of MR elements 50 of the second resistance section 12, the direction of the external magnetic field is set to the direction opposite to the first reference direction D1 (-Y direction). The magnetization direction of the initially magnetization-pinned layer in each of the other plurality of initial MR elements can thereby be set to the direction opposite to the first reference direction D1. In this way, the plurality of MR elements 50 of the second resistance section 12 are formed.

[0071] Similarly, for another plurality of initial MR elements that will later become the plurality of MR elements 50 of the third resistance section 13, the direction of the external magnetic field is set to the second reference direction D2. The magnetization direction of the magnetization-pinned layer in each of the other plurality of initial MR elements can thereby be set to the second reference direction D2. In this way, the plurality of MR elements 50 of the third resistance section 13 are formed.

[0072] Similarly, for the other plurality of initial MR elements that will later become the plurality of MR elements 50 of the fourth resistance section 14, the direction of the external magnetic field is set to the direction opposite to the second reference direction D2. The magnetization direction of the magnetization-pinned layer in each of the other plurality of initial MR elements can thereby be set to the direction opposite to the second reference direction D2. In this way, the plurality of MR elements 50 of the fourth resistance section 14 are formed.

[0073] The following describes the operation and effects of the angle detection device 1 according to the present embodiment. In the present embodiment, the angle sensor 10 generates the first and second detection signals S1 and S2 to generate the first to third logic signals Su, Sv, and Sw. According to the present embodiment, the configuration of the angle sensor 10 can thereby be simplified compared to the case where three detection signals with corresponding differential phases are generated to generate the three logic signals. For example, according to the present embodiment, magnetic detection elements whose sensitivity axes lie in a direction intersecting both the first and second reference directions D1 and D2 can be omitted.

[0074] If Hall elements are used as magnetic detection elements, a temperature sensor is required to compensate for temperature-related fluctuations in the output characteristics of the Hall elements. However, if the MR elements 50 are used as magnetic detection elements, the temperature sensor can be omitted. This effect will now be explained with reference to Fig. 8 described.

[0075] Fig. 8 is an explanatory diagram (waveform diagram) for describing the action of the angle sensor 10. In Fig. In Figure 8, the horizontal axis shows the angle of rotation θM of the motor 110, and the vertical axis shows the magnitude of the signals. The vertical axis is given in an arbitrary unit. In Fig. 8, the curve denoted by symbol S1r represents the waveform of the first detection signal S1 at room temperature. The curve denoted by symbol S1h represents the waveform of the first detection signal S1 at high temperature. The curve denoted by symbol S2r represents the waveform of the second detection signal S2 at room temperature. The curve denoted by symbol S2h represents the waveform of the second detection signal S2 at high temperature.

[0076] As from Fig. As can be seen from Fig. 8, the amplitudes of the first and second detection signals S1 and S2 change with temperature changes. However, the phases of the first and second detection signals S1 and S2 do not change even if the temperature changes. Therefore, the timing at which each of the first to third logic signals Su, Sv, and Sw switches between the high and low levels does not change, and the detection result of the rotation angle θM of the motor 110 does not change either. Since the detection result of the rotation angle θM of the motor 110 does not change even with temperature changes, the temperature sensor can be omitted if the MR elements 50 are used as the magnetic detection elements.

[0077] In the present embodiment, the angle sensor 10 can be formed in a single chip by forming the plurality of MR elements 50 using laser light and external magnetic fields with predetermined directions as described above. This can also simplify the configuration of the angle sensor 10. [Second embodiment]

[0078] Next, a second embodiment of the present invention will be described. First, a schematic structure of a motor device according to the second embodiment of the present invention will be described with reference to Fig. 9 described. Fig. 9 is an explanatory diagram showing the structure of the motor device according to the present embodiment.

[0079] In the present embodiment, the angle detection device 1 is located outside the rotation axis C. For example, the angle detection device 1 is located outside the outer peripheral region of the magnetic field generator 5. As described in the first embodiment, the angle sensor 10 is designed to detect the components of the rotating magnetic field MF in directions parallel to the reference plane PL at the reference position PR within the reference plane PL (see Fig. 4). In the present embodiment, the reference position PR is away from the rotation axis C (for example, at a position where the angle detection device 1 is located).

[0080] In the present embodiment, at least one of the first and second reference directions D1 and D2 is different from that in the first embodiment. Otherwise, the configuration of the motor device 100 according to the present embodiment is the same as that of the first embodiment.

[0081] Next, the reason why at least one of the first and second reference directions D1 and D2 differs from the first embodiment will be described. Fig. Figure 10 is a characteristic diagram showing a relationship between the rotation angle θM of the motor 110 and the angle of the rotating magnetic field θ. In Fig. In Figure 10, the horizontal axis shows the rotation angle θM, and the vertical axis shows the angle of the rotating magnetic field θ. Ideally, the value of the angle of the rotating magnetic field θ that the direction of the rotating magnetic field MF makes with the direction of the reference magnetic field DR is the same as the rotation angle θM. However, in the present embodiment, the value of the angle of the rotating magnetic field θ deviates from that of the rotation angle θM, and the amount of deviation of the angle of the rotating magnetic field θ varies depending on the value of the rotation angle θM. This is because, at the reference position PR in the present embodiment, the waveform indicating a change in the strength of a component of the rotating magnetic field MF in one direction (hereinafter referred to as the magnetic field strength waveform) is distorted from a sine curve.

[0082] Assume that an angle detection device of a comparative example is located at the same position as the angle detection device 1 according to the present embodiment. The angle detection device of the comparative example includes an angle sensor of the comparative example and a logic signal generation section of the comparative example. The angle sensor of the comparative example has the same configuration as the angle sensor 10 of the first embodiment, including the first and second reference directions D1 and D2, that is, the direction of the first magnetization of the magnetization-pinned layer 52 in each of the plurality of MR elements 50. The angle sensor of the comparative example is configured to output a first detection signal S101 and a second detection signal S102 corresponding to the first detection signal S1 and the second detection signal S2, respectively.

[0083] The logic signal generating section of the comparative example has the same configuration as the logic signal generating section 20 according to the first embodiment. The logic signal generating section of the comparative example is configured to generate the first to third logic signals Su, Sv, and Sw of the comparative example based on the first and second detection signals S101 and S102.

[0084] Fig. 11 is a waveform diagram showing the waveform of each of the first and second detection signals S101 and S102 according to the comparative example. In Fig. In Figure 11, the horizontal axis shows the angle of rotation θM of motor 110, and the vertical axis shows the magnitude of the signals. The vertical axis is given in any unit.

[0085] The first detection signal S101 corresponds to the strength of the rotating magnetic field MF component in the direction parallel to the Y direction (the same direction as the first reference direction D1 in the first embodiment) at the reference position PR. The second detection signal S102 corresponds to the strength of the rotating magnetic field MF component in a direction parallel to a direction rotated 60° from the Y direction to the -X direction (the same direction as the second reference direction D2 in the first embodiment) at the reference position PR. As described above, the waveform of the magnetic field strength is distorted by a sine curve. The waveform of each of the first and second detection signals S101 and S102 is therefore also distorted by a sine curve.

[0086] Fig. Figure 12 is a timing chart showing the first to third logic signals Su, Sv, and Sw of the comparative example. In the comparative example, the timing (rotation angle θM) at which the second logic signal Sv switches between the high and low levels is different from that in Fig. 7 of the first embodiment. Similarly, in the comparative example, the timing (rotation angle θM) at which the third logic signal Sw switches between the high and low levels differs from that in Fig. 7 shown in the first embodiment.

[0087] As described above, in the comparative example, the timing at which each of the second and third logic signals Sv and Sw changes between the high and low levels is different from that of the first embodiment. This is because the waveform of each of the first and second detection signals S101 and S102 is distorted from a sine wave. Therefore, the timing (rotation angle θM) at which the waveforms of the first and second detection signals S101 and S102 intersect is different from the timing at which the waveforms of the first and second detection signals S101 and S102 intersect Fig. 6 intersect the first and second detection signals S1 and S2 of the first embodiment. As a result, the timing at which each of the second and third logic signals Sv and Sw switches between the high and low levels differs from that in the first embodiment.

[0088] The timing at which the first logic signal Su changes between the high level and the low level is essentially the same as that in Fig. 7 in the first embodiment. This is because the phase of the first detection signal S1 and that of the first detection signal S101 are adjusted for comparison purposes.

[0089] As from Fig. As can be seen from Fig. 12, in the comparative example, the rotation angle θ M cannot be detected in units of 60° (every 1 / 6 of a revolution). In contrast, in the present embodiment, the phase and amplitude of at least one of the first and second detection signals S1 and S2 are adjusted so that the rotation angle θ M can be detected in units of 60° (every 1 / 6 of a revolution).

[0090] In the present embodiment, the phase of at least one of the first and second detection signals S1 and S2 is adjusted by adjusting at least one of the first and second reference directions D1 and D2 differently than in the first embodiment. The case of adjusting the phase and amplitude of the second detection signal S2 will now be described as an example.

[0091] The phase of the second detection signal S2 can be adjusted by adjusting the second reference direction D2, which serves as a reference for the direction of the first magnetization of the magnetization-pinned layer 52 in each of the plurality of MR elements 50 of the third and fourth resistance sections 13 and 14. In the present embodiment, the second reference direction D2 is a direction rotated from the Y direction (first reference direction D1) to the -X direction by an angle greater than 60°, or from the Y direction to the -X direction by an angle smaller than 60°. The amplitude of the second detection signal S2 can be adjusted, for example, with an amplifier. The amplifier can be included in the angle sensor 10 or the logic signal generation section 20.

[0092] In the present embodiment, the phase and amplitude of the second detection signal S2 are adjusted so that the waveform of the first detection signal S1 and that of the second detection signal S2 overlap at the same timing (rotation angle θ M) as in the first embodiment. The timing at which each of the first to third logic signals Su, Sv, and Sw switches between the high and low levels can thereby be made identical to that of the first embodiment.

[0093] Fig. 13 is a waveform diagram showing the waveform of each of the first and second detection signals S1 and S2 in the present embodiment. In Fig. In Figure 13, the horizontal axis shows the angle of rotation θM of the motor 110, and the vertical axis shows the magnitude of the signals. The vertical axis is given in an arbitrary unit. The waveform of the Fig. 13 is the same as that of the first detection signal S101 of the Fig. 11 shown comparison example. Fig. 13 also shows the waveform of the second detection signal S102 of the Fig. 11. The second detection signal S102 essentially corresponds to the second detection signal S2 before phase and amplitude adjustment.

[0094] As in Fig. As shown in Fig. 13, in the present embodiment, the second detection signal S2 is set so that the waveform of the first detection signal S1 and that of the second detection signal S2 intersect at rotation angles θM of 120° and 300°. In the present embodiment, the angle formed between the first reference direction D1 and the second reference direction D2 is different from the angle corresponding to the phase difference between the first detection signal S1 and the second detection signal S2.

[0095] Fig. 14 is a timing chart showing the first to third logic signals Su, Sv, and Sw. As shown in Fig. 14, the timing at which each of the first to third logic signals Su, Sv and Sw changes between the high and low levels is substantially the same as that shown in Fig. 7 in the first embodiment. Thus, according to the present embodiment, the rotation angle θ M can be detected in units of 60° (every 1 / 6 of a revolution).

[0096] In the present embodiment, the phase and amplitude of the first detection signal S1 may be adjusted instead of adjusting the phase and amplitude of the second detection signal S2. Alternatively, the phases and amplitudes of both the first and second detection signals S1 and S2 may be adjusted.

[0097] As already described, in the present embodiment, the direction of at least one of the first and second reference directions D1 and D2 is different from that of the first embodiment to enable the detection of the rotation angle θM in units of 60° (every 1 / 6 of a turn).

[0098] The structure, operation and effects of the present embodiment are otherwise the same as those of the first embodiment. [Third Embodiment]

[0099] Next, a third embodiment of the present invention will be described with reference to Fig. 15 described. Fig. 15 is an explanatory diagram showing the interior of an angle detection device according to the present embodiment.

[0100] An angle detection device 1 according to the present embodiment includes a rectangular solid-shape chip 6 instead of the first and second chips 2 and 3 in the first embodiment. The chip 6 is mounted on the substrate 4. The chip 6 includes the angle sensor 10 and the logic signal generating section 20. In the chip 6, either the angle sensor 10 or the logic signal generating section 20 may be stacked on the other of the angle sensor 10 and the logic signal generating section 20. Alternatively, the angle sensor 10 and the logic signal generating section 20 may be arranged at respective different positions in a direction parallel to the XY plane.

[0101] The angle detection device 1 according to the present embodiment also includes a plurality of wires 45 connecting the chip 6 and the plurality of leads 43 instead of the plurality of wires 41 and the plurality of wires 42 in the first embodiment.

[0102] The structure, operation and effects of the present embodiment are otherwise the same as those of the first or second embodiment. [Fourth Embodiment]

[0103] Next, a fourth embodiment of the present invention will be described with reference to the Fig. 16 and Fig. 17 described. Fig. 16 is an explanatory diagram showing the interior of a first electronic component in the present embodiment. Fig. 17 is an explanatory diagram showing the interior of a second electronic component in the present embodiment.

[0104] An angle detection device 1 according to the present embodiment includes a first electronic component 1A and a second electronic component 1B instead of the substrate 4, the plurality of wires 41, the plurality of wires 42, the plurality of leads 43, and the sealing resin 44 in the first embodiment. The first electronic component 1A includes the first chip 2 with the angle sensor 10. The second electronic component 1B includes the second chip 3, which includes the logic signal generating section 20.

[0105] The first electronic component 1A further includes a substrate 4A on which the first chip 2 (angle sensor 10) is mounted, a plurality of leads 43A, a plurality of wires 41A connecting the first chip 2 and the plurality of leads 43A, and a sealing resin 44A sealing the first chip 2.

[0106] The second electronic component 1B further includes a substrate 4B on which the second chip 3 (logic signal generating section 20) is mounted, a plurality of leads 43B, a plurality of wires 42B connecting the second chip 3 and the plurality of leads 43B, and a sealing resin 44B sealing the second chip 3.

[0107] The first electronic component 1A may be located at the same position as the angle detection device 1 according to the first embodiment or at the same position as the angle detection device 1 according to the second embodiment. The second electronic component 1B may be arranged near the first electronic component 1A or away from the first electronic component 1A.

[0108] The structure, operation and effects of the present embodiment are otherwise the same as those of the first or second embodiment. [Fifth Embodiment]

[0109] Next, a fifth embodiment of the present invention will be described. A configuration of an angle sensor 10 in the present embodiment will first be described with reference to Fig. 18 described. Fig. 18 is a circuit diagram showing a circuit configuration of the angle sensor 10 in the present embodiment.

[0110] The angle sensor 10 in the present embodiment includes a first detection circuit 10A and a second detection circuit 10B. The first detection circuit 10A includes a power supply terminal 10Aa, a ground terminal 10Ab, a first output terminal 10Ac, a first resistance portion 11, and a second resistance portion 12. Each of the first and second resistance portions 11 and 12 has the same configuration as in the first embodiment.

[0111] The first resistance portion 11 is provided in the circuit configuration between the power supply terminal 10Aa and the first output terminal 10Ac. The second resistance portion 12 is provided in the circuit configuration between the ground terminal 10Ab and the first output terminal 10Ac. A voltage or current of a predetermined magnitude is applied to the power supply terminal 10Aa. The ground terminal 10Ab is grounded. The first output terminal 10Ac outputs a signal corresponding to the potential at the connection point of the first resistance portion 11 and the second resistance portion 12 as a first detection signal S1.

[0112] The second detection circuit 10B includes a power supply terminal 10Ba, a ground terminal 10Bb, a second output terminal 10Bc, a third resistance portion 13, and a fourth resistance portion 14. Each of the third and fourth resistance portions 13 and 14 has the same configuration as in the first embodiment.

[0113] The third resistance section 13 is provided in the circuit configuration between the power supply terminal 10Ba and the second output terminal 10Bc. The fourth resistance section 14 is provided in the circuit configuration between the ground terminal 10Bb and the second output terminal 10Bc. A voltage or current of a predetermined magnitude is applied to the power supply terminal 10Ba. The ground terminal 10Bb is grounded. The second output terminal 10Bc outputs a signal corresponding to the potential at the connection point of the third resistance section 13 and the fourth resistance section 14 as the second detection signal S2.

[0114] The first output terminal 10Ac of the first detection circuit 10A is connected to the first input terminal 20c (see Fig. 3) of the logic signal generating section 20. The second output terminal 10Bc of the second detection circuit 10B is connected to the second input terminal 20d (see Fig. 3) of the logic signal generating section 20.

[0115] Next, a first example and a second example of the configuration of the angle detection device 1 according to the present embodiment will be described. The first example will first be described with reference to Fig. 19 described. Fig. 19 is an explanatory diagram showing the first example of the configuration of the angle detection device 1. In the first example, the angle detection device 1 includes rectangular solid-shape chips 2A and 2B instead of the first chip 2 in the first embodiment. The chips 2A and 2B are both mounted on the second chip 3 (logic signal generating section 20). The chip 2A includes the first detection circuit 10A. The chip 2B includes the second detection device 10B.

[0116] In the first example, the angle detection device 1 includes a plurality of wires 41C connecting the chip 2A and the second chip 3, and a plurality of wires 41D connecting the chip 2B and the second chip 3, instead of the plurality of wires 41 in the first embodiment.

[0117] Next, the second example is presented with reference to Fig. 20 described. Fig. Fig. 20 is an explanatory diagram showing the second example of the configuration of the angle detection device 1. In the second example, as in the first example, the angle detection device 1 includes the chips 2A and 2B. Specifically, in the second example, the chips 2A and 2B are stacked on the second chip 3 (logic signal generating section 20). In the Fig. In the example shown in Figure 20, chip 2B is mounted on the second chip 3. Chip 2A is mounted on chip 2B.

[0118] In the second example, the angle detection device 1 includes a plurality of wires 41E connecting the chip 2A and the second chip 3 instead of the plurality of wires 41 in the first embodiment. The second detection circuit 10B in the chip 2B can be connected to the logic signal generating section 20 in the second chip 3 via the chip 2A and the plurality of wires 41E. Alternatively, the second detection circuit 10B in the chip 2B can be connected to the logic signal generating section 20 in the second chip 3 without involving the chip 2A or the plurality of wires 41E.

[0119] The structure, operation and effects of the present embodiment are otherwise the same as those of the first or second embodiment. [Sixth Embodiment]

[0120] A sixth embodiment of the present invention will be described below. First, a configuration of an angle detection device 1 according to the present embodiment will be described with reference to Fig. 21 described. Fig. 21 is a circuit diagram showing a circuit configuration of the angle detection device 1.

[0121] In the present embodiment, the second reference direction D2 (see Fig. 4) Different from the first embodiment. As described in the first embodiment, the second reference direction D2 is a reference direction for the first magnetization direction of the magnetization-pinned layer 52 in each of the plurality of MR elements 50 of the third and fourth resistance sections 13 and 14 of the angle sensor 10. In the present embodiment, the second reference direction D2 is a direction 30° rotated from the -X direction to the -Y direction. An angle formed between the first reference direction D1 (Y direction) and the second reference direction D2 is 120°.

[0122] In the present embodiment, the angle sensor 10 is configured to output a second detection signal S21 instead of the second detection signal S2 in the first embodiment. The second detection signal S21 is a signal corresponding to the potential at the connection point of the third resistance portion 13 and the fourth resistance portion 14, and is output from the second output terminal 10d of the angle sensor 10. The second detection signal S21 has a correspondence with the strength of the component of the rotating magnetic field MF in a direction parallel to the second reference direction D2. A phase difference between the first detection signal S1 and the second detection signal S21 is 120°.

[0123] In the present embodiment, the logic signal generating section 20 includes another power supply terminal 20h, another ground terminal 20i, an inverting amplifier 26, and resistors 27 and 28. The inverting amplifier 26 includes a first input port 26a, a second input port 26b, and an output port 26c.

[0124] One end of resistor 27 is connected to the power supply terminal 20h. One end of resistor 28 is connected to the other end of resistor 27. The other end of resistor 28 is connected to the ground terminal 20i. A voltage of a certain magnitude is applied to the power supply terminal 20h. The ground terminal 20i is grounded.

[0125] The first input port 26a of the inverting amplifier 26 is connected to the junction point of the resistor 27 and the resistor 28. The second input port 26b of the inverting amplifier 26 is connected to the second terminal 20d of the logic signal generating section 20.

[0126] In the present embodiment, the first input port 22a of the second comparator 22 and the second input port 23b of the third comparator 23 are connected to the output terminal 26c of the inverting amplifier 26 instead of the second input terminal 20d.

[0127] The inverting amplifier 26 is configured to output a signal obtained by inverting the phase of the second detection signal S21 by 180°. The signal obtained by inverting the phase of the second detection signal S21 by 180° is hereinafter referred to as the second detection signal S22. The second detection signal S22 corresponds to the strength of the component of the rotating magnetic field MF in the direction parallel to the second reference direction D2.

[0128] Otherwise, the configuration of the angle detection device 1 according to the present embodiment is the same as that of the first embodiment.

[0129] Next, the first detection signal S1, the second detection signals S21 and S22, and the first to third logic signals Su, Sv, and Sw in the present embodiment will be described. Fig. Fig. 22 is a waveform diagram showing the waveform of each of the first and second detection signals S1, S21, and S22 in the present embodiment. Fig. In Figure 22, the horizontal axis shows the angle of rotation θM of the motor 110, and the vertical axis shows the magnitude of the signals. The vertical axis is given in an arbitrary unit. As shown in Fig. 22, the phase difference between the first detection signal S1 and the second detection signal S22 is 60°.

[0130] Fig. 23 is a timing chart showing the first to third logic signals Su, Sv, and Sw in the present embodiment. In the present embodiment, as in the first embodiment, the first comparator 21 outputs a high-level signal when the rotation angle θM is greater than 0° and less than 180°, and outputs a low-level signal when the rotation angle θM is greater than 180° and less than 360°.

[0131] In the present embodiment, the second detection signal S22 is input to the first input port 22a of the second comparator 22. As shown in Fig. 22, the value of the second detection signal S22 is greater than that of the reference voltage (0 on the vertical axis of Fig. 22) when the rotation angle θM is greater than or equal to 0° and less than 120° or greater than 300° and less than or equal to 360°. The value of the second detection signal S22 is smaller than the value of the reference voltage (0 on the vertical axis of Fig. 22) when the rotation angle θM is greater than 120° and less than 300°. The second comparator 22 thus outputs a high-level signal when the rotation angle θM is greater than or equal to 0° and less than 120°, or greater than 300° and less than or equal to 360°, and outputs a low-level signal when the rotation angle θM is greater than 120° and less than 300°.

[0132] In the present embodiment, the second detection signal S22 is input to the second input port 23b of the third comparator 23. The third comparator 23 compares the value of the first detection signal S1 and that of the second detection signal S22 and outputs the third logic signal Sw. As shown in Fig. As shown in Fig. 22, the value of the first detection signal S1 is greater than that of the second detection signal S22 when the rotation angle θM is greater than 60° and less than 240°. The value of the first detection signal S1 is smaller than that of the second detection signal S22 when the rotation angle θM is greater than or equal to 0° and less than 60°, or greater than 240° and less than or equal to 360°. Thus, the third comparator 23 outputs a high-level signal when the rotation angle θM is greater than 60° and less than 240°, and outputs a low-level signal when the rotation angle θM of the motor 110 is greater than or equal to 0° and less than 60°, or greater than 240° and less than 360°.

[0133] In the present embodiment, when the first to third logic signals Su, Sv, and Sw are at the high level, the high level, and the low level, respectively, the control circuit 121 of the logic signal generating section 20 determines that the rotation angle θM is in the range of 0° to 60°. When the first to third logic signals Su, Sv, and Sw are at the high level, the high level, and the high level, respectively, the control circuit 121 determines that the rotation angle θM of the motor 110 is in the range of 60° to 120°. In this way, the control circuit 121 detects the rotation angle θM of the motor 110 in units of 60° (every 1 / 6 revolution) based on the combination of the levels of the first to third logic signals Su, Sv, and Sw.

[0134] The inverting amplifier 26 may be included in the angle sensor 10 instead of the logic signal generating section 20. In such a case, the second detection signal S22 is output from the second output terminal 10d of the angle sensor 10. The configuration and operation of the logic signal generating section 20 are the same as in the first embodiment.

[0135] Otherwise, the configuration of the angle detection device 1 according to the present embodiment is the same as that of the first or second embodiment. [Seventh Embodiment]

[0136] Next, a seventh embodiment of the present invention will be described with reference to Fig. 24 described. Fig. 24 is a circuit diagram showing a circuit configuration of an angle detection device 1.

[0137] The angle detection device 1 according to the present embodiment includes an angle sensor 200 instead of the angle sensor 10 of the first embodiment. The angle sensor 200 is configured to detect the rotating magnetic field MF and output the first detection signal S1 and the second detection signal S2.

[0138] The angle sensor 200 includes power supply terminals 200a1 and 200a2, ground terminals 200b1 and 200b2, a first output terminal 200c, a second output terminal 200d, a first bridge circuit 210, a second bridge circuit 220, a first differential amplifier 231, and a second differential amplifier 232.

[0139] The first bridge circuit 210 includes a first resistance section 211, a second resistance section 212, a third resistance section 213, a fourth resistance section 214, and a plurality of MR elements 50 constituting the first to fourth resistance sections 211 to 214.

[0140] One end of each of the first and third resistance sections 211 and 213 is connected to a connection point P11. One end of the second and fourth resistance sections 212 and 214 is connected to a connection point P12. The other ends of the first and second resistance sections 211 and 212 are connected to a connection point P13. The other ends of the third and fourth resistance sections 213 and 214 are connected to a connection point P14.

[0141] Connection point P11 is connected to the power supply terminal. Connection point P12 is connected to the ground terminal 200b1. A voltage or current of a specified magnitude is applied to the power supply terminal 200a1. The ground terminal 200b1 is grounded.

[0142] An output port of the first differential amplifier 231 is connected to the first output terminal 200c. The first differential amplifier 231 generates a signal corresponding to a potential difference between the connection points P13 and P14 as a first detection signal S1. The first output terminal 200c outputs the first detection signal S1.

[0143] In the present embodiment, the first magnetization of the magnetization-pinned layer 52 in each of the plurality of MR elements 50 constituting the first and fourth resistance sections 211 and 214 includes a component in the first reference direction D1 (see Fig. 4). The first magnetization of the magnetization-pinned layer 52 in each of the plurality of MR elements 50 constituting the second and third resistance sections 212 and 213 includes a component in the direction opposite to the first reference direction D1. The first detection signal S1 corresponds to the strength of the component of the rotating magnetic field MF in a direction parallel to the first reference direction D1.

[0144] The second bridge circuit 220 includes a first resistance section 221, a second resistance section 222, a third resistance section 223, a fourth resistance section 224, and the plurality of MR elements 50 constituting the first to fourth resistance sections 221 to 224.

[0145] One end of each of the first and third resistance sections 221 and 223 is connected to a connection point P21. One end of the second and fourth resistance sections 222 and 224 is connected to a connection point P22. The other ends of the first and second resistance sections 221 and 222 are connected to a connection point P23. The other ends of the third and fourth resistance sections 223 and 224 are connected to a connection point P24.

[0146] Connection point P21 is connected to the power supply terminal 200a2. Connection point P22 is connected to the ground terminal 200b2. A specific voltage or current is applied to the power supply terminal 200a2 of the power supply. The ground terminal 200b2 is grounded.

[0147] An output port of the second differential amplifier 232 is connected to the second output terminal 200d. The second differential amplifier 232 generates a signal corresponding to a potential difference between the connection points P23 and P24 as the second detection signal S2. The second output terminal 200d outputs the second detection signal S2.

[0148] In the present embodiment, the first magnetization of the magnetization-pinned layer 52 in each of the plurality of MR elements 50 constituting the first and fourth resistance sections 221 and 224 includes a component in the second reference direction D2 (see Fig.4). The first magnetization of the magnetization-pinned layer 52 in each of the plurality of MR elements 50 constituting the second and third resistance sections 222 and 223 includes a component in the direction opposite to the second reference direction D2. The second detection signal S2 corresponds to the strength of the component of the rotating magnetic field MF in a direction parallel to the reference direction D2.

[0149] The logic signal generating section 20 has the same configuration as the first embodiment. The first output terminal 200c of the angle sensor 200 is connected to the first input terminal 20c of the logic signal generating section 20. The second output terminal 200d of the angle sensor 200 is connected to the second input terminal 20d of the logic signal generating section 20.

[0150] Otherwise, the configuration of the angle detection device 1 according to the present embodiment is the same as that of the first or second embodiment.

[0151] The present invention is not limited to the aforementioned embodiments, and various modifications may be made. For example, the third and fourth resistance portions 13 and 14 of the angle sensor 10 may have the same configuration as the first and second resistance portions 11 and 12 of the angle sensor 10, including the directions of the first magnetizations of the magnetization-pinned layers 52. In such a case, the pair of first and second resistance portions 11 and 12 and the pair of third and fourth resistance portions 13 and 14 are arranged at different positions, respectively, so that the value of a phase difference between the first detection signal S1 and the second detection signal S2 is not an integer multiple of 90°.

[0152] At least part of the control circuit 121 and the logic signal generating section 20 can be implemented by an ASIC or a microcomputer.

[0153] The angle detection device 1 may also contain an optical angle sensor instead of the angle sensor 10 or 200.

[0154] As described above, the angle detection device according to the present invention is used for a driving circuit for a motor.The angle detection device according to the present invention includes an angle sensor configured to detect a physical quantity that periodically changes in response to a rotation angle of the motor, and output a first detection signal and a second detection signal having a phase difference whose value is not an integer multiple of 90°, and a logic signal generating section configured to generate a first logic signal using the first detection signal, generate a second logic signal having a phase different from that of the first logic signal using the second detection signal, and generate a third logic signal having a phase different from that of the first and second logic signals using the first and second detection signals.

[0155] In the angle detection device according to the present invention, the logic signal generating section may include a first comparator configured to generate the first logic signal, a second comparator configured to generate the second logic signal, and a third comparator configured to generate the third logic signal. The angle sensor may include a first output terminal that outputs the first detection signal and a second output terminal that outputs the second detection signal. Each of the first, second, and third comparators may have a first input port and a second input port. The first output terminal may be connected to the first input port of the first comparator and the first input port of the third comparator. The second output terminal may be connected to the first input port of the second comparator and the second input port of the third comparator.

[0156] In the angle detection device according to the invention, the physical quantity may be a magnetic field whose direction changes in response to a change in the angle of rotation. The angle sensor may include a plurality of magnetic detection elements, each configured to detect a magnetic field. The plurality of magnetic detection elements may include a plurality of first magnetic detection elements configured to generate the first detection signal and a plurality of second magnetic detection elements configured to generate the second detection signal.Each of the plurality of first and second magnetoresistive elements may include a magnetization-pinned layer having a first magnetization whose direction is fixed, a free layer having a second magnetization whose direction is variable depending on the magnetic field, and an intermediate layer located between the magnetization-pinned layer and the free layer.A difference between an angle that a first magnetic field direction forms with a first reference direction and an angle that a second magnetic field direction forms with a second reference direction may be an angle that is not an integer multiple of 90°, wherein the first reference direction is a reference direction for the direction of the first magnetization in each of the plurality of first magnetoresistive elements, the second reference direction is a reference direction for the direction of the first magnetization in each of the plurality of second magnetoresistive elements, the first magnetic field direction is a direction of the magnetic field detected by each of the plurality of first magnetoresistive elements at a predetermined time when the magnetic field changes periodically, and the second magnetic field direction is a direction of the magnetic field detected by each of the plurality of second magnetoresistive elements at the predetermined time.

[0157] When the plurality of magnetic detection elements includes the plurality of first magnetoresistive elements and the plurality of second magnetoresistive elements, an angle formed between the first reference direction and the second reference direction may not be an integer multiple of 90°. In such a case, the angle formed between the first reference direction and the second reference direction may be the same as an angle corresponding to the phase difference between the first detection signal and the second detection signal, or may be different from the angle corresponding to the phase difference between the first detection signal and the second detection signal. The angle detection device according to the present invention may further include a chip including the plurality of first magnetoresistive elements and the plurality of second magnetoresistive elements.

[0158] The angle detection device according to the present invention may further include a first chip including the angle sensor and a second chip including the logic signal generating section. One of the first and second chips may be mounted on the other of the first and second chips.

[0159] The angle detection device according to the present invention may further include a chip including the angle sensor and the logic signal generating section.

[0160] A motor device according to the present invention includes the angle detection device according to the present invention and the motor.

[0161] The motor device according to the present invention may further include a magnetic field generating section configured to generate a magnetic field whose direction changes in response to a change in the rotation angle. The physical quantity may be the magnetic field. The angle sensor may be configured to detect the magnetic field generated by the magnetic field generating section.

[0162] A logic signal generator according to the present invention is configured to generate three logic signals each having different phases. The logic signal generator according to the present invention is configured to receive a first detection signal and a second detection signal having a phase difference whose value is not an integer multiple of 90°, generate and output a first logic signal using the first detection signal, generate and output a second logic signal having a phase different from that of the first logic signal using the second detection signal, and generate and output a third logic signal having a phase different from that of the first and second logic signals using the first and second detection signals.

[0163] Obviously, many modifications and variations of the present invention are possible in light of the above teachings. Thus, it is to be understood that, within the scope of the appended claims and their equivalents, the present invention may be practiced in forms other than those described above. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP S60-134792 A

[0004] EP 2546611 A1

[0004] EP 2843825 A1

[0004] DE 19619806 A1

[0005]

Claims

[1] An angle detection device (1) used for a driving circuit (120) for a motor (110), comprising: an angle sensor (10) configured to detect a physical quantity that periodically changes in response to a rotation angle (θM) of the motor (110), and to output a first detection signal (S1) and a second detection signal (S2; S21, S22) with a phase difference whose value is not an integer multiple of 90°; and a logic signal generating section (20) configured to generate a first logic signal (Su) using the first detection signal (S1), to generate a second logic signal (Sv) having a phase different from that of the first logic signal (Su) using the second detection signal (S2; S21, S22), and to generate a third logic signal (Sw) having a phase different from that of the first logic signal (Su) and the second logic signal (Sv) using the first detection signal (S1) and the second detection signal (S2; S21, S22). [2] The angle detection device (1) according to claim 1, wherein the logic signal generating section (20) includes a first comparator (21) configured to generate the first logic signal (Su), a second comparator (22) configured to generate the second logic signal (Sv), and a third comparator (23) configured to generate the third logic signal (Sw). [3] The angle detection device (1) according to claim 2, wherein: the angle sensor (10) includes a first output terminal (10c; 10Ac; 200c) which outputs the first detection signal (S1) and a second output terminal (10d; 10Bc; 200d) which outputs the second detection signal (S2; S21, S22); the first comparator (21), the second comparator (22) and the third comparator (23) each have a first input port (21a, 22a, 23a) and a second input port (21b, 22b, 23b); the first output terminal (10c; 10Ac; 200c) is connected to the first input port (21a) of the first comparator (21) and the first input port (23a) of the third comparator (23); and the second output terminal (10d; 10Bc; 200d) is connected to the first input port (22a) of the second comparator (22) and the second input port (23b) of the third comparator (23). [4] The angle detection device (1) according to claim 1, wherein: the physical quantity is a magnetic field (MF) whose direction rotates in response to a change in the angle of rotation (θM); and the angle sensor (10) includes a plurality of magnetic detection elements (50) each configured to detect the magnetic field (MF). [5] The angle detection device (1) according to claim 4, wherein: the plurality of magnetic detection elements (50) include a plurality of first magnetoresistive elements configured to generate the first detection signal (S1) and a plurality of second magnetoresistive elements configured to generate the second detection signal (S2; S21, S22); each of the plurality of first and second magnetoresistive elements includes a magnetization-pinned layer (52) having a first magnetization whose direction is fixed, a free layer (54) having a second magnetization whose direction is variable depending on the magnetic field (MF), and an intermediate layer (53) disposed between the magnetization-pinned layer (52) and the free layer (54); and a difference between an angle formed by a first magnetic field direction with a first reference direction (D1) and an angle formed by a second magnetic field direction with a second reference direction (D2) is an angle that is not an integer multiple of 90°, wherein the first reference direction (D1) is a reference direction for the direction of the first magnetization in each of the plurality of first magnetoresistive elements, the second reference direction (D2) is a reference direction for the direction of the first magnetization in each of the plurality of second magnetoresistive elements, the first magnetic field direction is the direction of the magnetic field (MF) detected by each of the plurality of first magnetoresistive elements at a predetermined time when the magnetic field (MF) changes periodically, and the second magnetic field direction is the direction of the magnetic field (MF),which is detected by each of the plurality of second magnetoresistive elements at the predetermined time., [6] The angle detection device (1) according to claim 5, wherein an angle formed between the first reference direction (D1) and the second reference direction (D2) is not an integer multiple of 90°. [7] The angle detection device (1) according to claim 5, wherein an angle formed between the first reference direction (D1) and the second reference direction (D2) is the same as an angle corresponding to the phase difference between the first detection signal (S1) and the second detection signal (S2; S21, S22). [8] The angle detection device (1) according to claim 5, wherein an angle formed between the first reference direction (D1) and the second reference direction (D2) is different from an angle corresponding to the phase difference between the first detection signal (S1) and the second detection signal (S2). [9] The angle detection device (1) according to claim 5, further comprising a chip (2; 6; 2A, 2B) having the plurality of first magnetoresistive elements and the plurality of second magnetoresistive elements. [10] The angle detection device (1) according to claim 1, further comprising: a first chip (2; 2A, 2B) having the angle sensor (10); and a second chip (3) having the logic signal generating section (20). [11] The angle detection device (1) according to claim 10, wherein one of the first chip (2; 2A, 2B) and the second chip (3) is mounted on the other of the first chip (2; 2A, 2B) and the second chip (3). [12] The angle detection device (1) according to claim 1, further comprising a chip (6) including the angle sensor (10) and the logic signal generating section (20). [13] A motor device (100) comprising: the angle detection device (1) according to one of claims 1 to 12; and the engine (110). [14] The motor device (100) according to claim 13, further comprising a magnetic field generating section (5) configured to generate a magnetic field (MF) whose direction rotates in response to a change in the rotation angle (θ M), wherein: the physical quantity is the magnetic field (MF); and the angle sensor (10) is designed to detect the magnetic field (MF) generated by the magnetic field generating section (5). [15] A logic signal generator (20) which is designed to generate three logic signals each having different phases, the logic signal generator (20) is designed to to obtain a first detection signal (S1) and a second detection signal (S2; S21, S22) with a phase difference whose value is not an integer multiple of 90°, to generate and output a first logic signal (Su) using the first detection signal (S1), to generate and output a second logic signal (Sv) having a phase different from the phase of the first logic signal (Su) using the second detection signal (S2; S21, S22), and to generate and output a third logic signal (Sw) having a phase different from the phase of the first logic signal (Su) and the phase of the second logic signal (Sw) using the first detection signal (S1) and the second detection signal (S2; S21, S22).

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