Physical quantity sensor and semiconductor device including the same

Abstract

To provide a physical quantity sensor capable of reducing inspection time in a process of inspection at low cost.SOLUTION: A physical quantity sensor 10A comprises: a first power terminal 11; a second power terminal 12; an input terminal 13; an output terminal 14; an input logic change detection circuit 21 detecting logic of a signal inputted via the input terminal 13, and outputting a polarity changeover signal corresponding to the detected logic while outputting an operation trigger signal when a change in the logic of the signal to be inputted is detected; a physical quantity detection circuit 23 detecting a physical quantity of polarity corresponding to the logic of the polarity changeover signal, and outputting a physical quantity detection signal corresponding to detection result of the physical quantity; an intermittent drive control circuit 22 causing the physical quantity detection circuit 23 to perform intermittent driving for repeating an operation period and an idle period at a certain period, and in response to receiving the operation trigger signal, outputting an intermittent drive control signal of causing the physical quantity detection circuit to transition from the idle period to the operation period; and an output driver 24, in response to the receiving the physical quantity detection signal, outputting an output signal to the output terminal 14.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a physical quantity sensor and a semiconductor device including the same. [Background technology]

[0002] In physical quantity sensors, such as magnetic sensors, an intermittent drive method that alternates between an active period and a rest period is widely used to reduce average current consumption. While the intermittent drive method has the advantage of significantly reducing average current consumption, it also has the disadvantage of increasing the inspection time and cost in the mass production inspection process.

[0003] Furthermore, a physical quantity sensor that has a sensing pole switching terminal in addition to a first power supply terminal, a second power supply terminal, and an output terminal and that employs an intermittent drive method has the disadvantage that it takes a long time from the start of the operating period after switching to the desired sensing pole until the desired detection result is obtained. From the perspective of eliminating this disadvantage, the above-mentioned conventional physical quantity sensor that employs an intermittent drive method and has a first power supply terminal, a second power supply terminal, an output terminal, and a sensing pole switching terminal is further configured to have an enable terminal to which a trigger that starts the operating period can be applied (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-217161 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in a physical quantity sensor in a four-terminal package with four terminals, if a circuit configuration having an enable terminal to which a trigger that starts an operating period can be applied is adopted without any ingenuity, the number of terminals will be insufficient. If a semiconductor device including an intermittent drive type physical quantity sensor having a first power supply terminal, a second power supply terminal, an output terminal, and a sensing pole switching terminal is formed in a four-terminal package using a conventional circuit configuration, it is not possible to provide an enable terminal, and the disadvantage of a long time from switching to the desired sensing pole until the desired sensing result is obtained cannot be overcome.

[0006] On the other hand, if it were possible to form a semiconductor device in a four-terminal package that includes a physical quantity sensor capable of applying a trigger to start an operating period, not only would the disadvantages described above be eliminated, but it would also lead to savings in materials, which would be a great benefit in terms of resource conservation and cost.

[0007] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide a physical quantity sensor that can reduce the inspection time in an inspection process at a lower cost than conventional methods, and a semiconductor device including the same. [Means for solving the problem]

[0008] The physical quantity sensor according to the present invention is characterized by comprising: a first power supply terminal, a second power supply terminal, an input terminal, an output terminal; an input logic change detection circuit that detects the logic of a signal input via the input terminal and outputs a polarity switching signal corresponding to the detected logic, while outputting an operation trigger signal when it detects a change in the logic of the input signal; a physical quantity detection circuit that detects a physical quantity of a polarity corresponding to the logic of the polarity switching signal and outputs a physical quantity detection signal corresponding to the physical quantity detection result; an intermittent drive control circuit that intermittently drives the physical quantity detection circuit to alternate between an operation period and a pause period at a predetermined cycle, and that outputs an intermittent drive control signal to transition from the pause period to the operation period in response to the operation trigger signal; and an output driver that receives the physical quantity detection signal and outputs an output signal to the output terminal. [Effects of the Invention]

[0009] According to the present invention, the inspection time in the inspection process can be reduced at a lower cost than conventional methods. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a block diagram schematically showing the configuration of a physical quantity sensor and a semiconductor device according to a first embodiment of the present invention. [Figure 2] 1A is a characteristic diagram showing the south pole detection operation of a magnetic sensor that is an example of a physical quantity sensor according to a first embodiment of the present invention, and FIG. 1B is a characteristic diagram showing the north pole detection operation of the magnetic sensor. [Figure 3] FIG. 3 is a timing chart showing the operation of the physical quantity sensor according to the first embodiment of the present invention. [Figure 4] FIG. 4 is a block diagram schematically showing the configuration of a physical quantity sensor and a semiconductor device according to a second embodiment of the present invention. [Figure 5] FIG. 10A is a characteristic diagram showing the south pole detection operation of a magnetic sensor, which is an example of a physical quantity sensor according to a second embodiment of the present invention; FIG. 10B is a characteristic diagram showing the bipolar detection operation of the magnetic sensor; and FIG. 10C is a characteristic diagram showing the north pole detection operation of the magnetic sensor. [Figure 6] FIG. 6 is a timing chart showing the operation of the physical quantity sensor according to the second embodiment of the present invention. [Figure 7] FIG. 10 is a block diagram schematically showing the configuration of a physical quantity sensor and a semiconductor device according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, each embodiment of the present invention will be described with reference to the drawings.

[0012] (First embodiment) FIG. 1 is a block diagram showing a physical quantity sensor 10A according to a first embodiment of the present invention and a semiconductor device 1A including the physical quantity sensor 10A. The semiconductor device 1A includes a semiconductor substrate 2 on which a physical quantity sensor 10A is formed. The physical quantity sensor 10A is, for example, a magnetic sensor that detects magnetism as a physical quantity. The physical quantity sensor 10A includes a first power supply terminal 11, a second power supply terminal 12, an input terminal 13, an output terminal 14, an input logic change detection circuit 21, an intermittent drive control circuit 22, a physical quantity detection circuit 23 including a physical quantity detection element (not shown), and an output driver 24.

[0013] An input logic change detection circuit 21 is connected to the input terminal 13. A physical quantity detection circuit 23 is connected to the input logic change detection circuit 21, and an intermittent drive control circuit 22 is also connected to the input logic change detection circuit 21. The physical quantity detection circuit 23 is connected to the intermittent drive control circuit 22. An output driver 24 is connected to the physical quantity detection circuit 23. An output terminal 14 is connected to the output driver 24.

[0014] Next, the operation of the physical quantity sensor 10A according to the first embodiment of the present invention will be described. A first power supply voltage is supplied to the first power supply terminal 11, and a second power supply voltage different from the first power supply voltage is supplied to the second power supply terminal 12. A signal (hereinafter simply referred to as "input signal") IN for selecting the pole detection operation is supplied to the input terminal 13. The input signal IN supplied to the input terminal 13 is a binary logic signal; for example, L logic results in S pole detection operation, and H logic results in N pole detection operation. The input logic change detection circuit 21 generates a polarity switching signal Sps corresponding to the logic of the input signal IN supplied to the input terminal 13 and outputs it to the physical quantity detection circuit 23. On the other hand, when the input logic change detection circuit 21 detects a change in the logic of the input signal IN supplied from the input terminal 13, it outputs an operation trigger signal TRIG to the intermittent drive control circuit 22. During steady state when the operation trigger signal TRIG is not supplied, the intermittent drive control circuit 22 outputs an intermittent drive control signal Sco to the physical quantity detection circuit 23 at a set cycle, which transitions the physical quantity sensor 10A from an idle period to an operation period so that the physical quantity sensor 10A alternates between an operation period and an idle period at a predetermined cycle. Furthermore, during non-steady state when the operation trigger signal TRIG is supplied, the intermittent drive control circuit 22 uses the operation trigger signal TRIG as a trigger to output the intermittent drive control signal Sco to the physical quantity detection circuit 23 regardless of the set cycle. During the operation period, the physical quantity detection circuit 23 detects a physical quantity of a polarity corresponding to the logic of the polarity switching signal Sps and outputs a physical quantity detection signal Sde corresponding to the detected physical quantity to the output driver 24. The output driver 24 outputs an output voltage OUT as an output signal to the output terminal 14 .

[0015] 2A is a characteristic diagram showing the south pole detection operation of a magnetic sensor, which is an example of the physical quantity sensor 10 A. Here, the horizontal axis represents the magnetic flux density B, and the vertical axis represents the output voltage OUT of the output terminal 14. When the input signal IN at the input terminal 13 is at logic low (IN="L"), the physical quantity sensor 10A operates in an S-pole detection state, detecting the magnetic flux density of the S-pole when the magnetic flux density B is in the region to the right of the vertical axis (magnetic flux density B=0), where B>0. The physical quantity sensor 10A has magnetoelectric conversion characteristics with hysteresis, where the operating point and the reset point are different. Specifically, when the magnetic flux density B increases from the N-pole side, which is the region to the left of the vertical axis (B<0), to the S-pole side, which is the region to the right of the vertical axis (B>0), the N-pole is not detected, and the output voltage OUT remains at the H level. Furthermore, when the magnetic flux density B increases and changes to the S-pole side, and the magnetic flux density B exceeds the magnetic flux density B0PS, which is the S-pole operating point (B>B0PS>0), the physical quantity sensor 10A transitions to an S-pole detection state, detecting the magnetic flux density B of the S-pole, and the output voltage OUT changes from the H level to the L level. On the one hand, when the magnetic flux density B changes in the direction of decreasing from the S pole (B>0) side to the N pole (B<0) side, the output voltage OUT maintains the L level even if the magnetic flux density B falls below the magnetic flux density BOPS. Further, when the magnetic flux density B changes in the decreasing direction and falls below the magnetic flux density BRPS (>0) which is the S pole return point (B<BRPS), the S pole detection state is released and the output voltage OUT changes from the L level to the H level.

[0016] FIG. 2(B) is a characteristic diagram showing the N pole detection operation of a magnetic sensor which is an example of the physical quantity sensor 10A. Here, the horizontal axis represents the magnetic flux density B and the vertical axis represents the output voltage OUT of the output terminal 14. When the input signal IN is at the H logic (IN = “H”), the physical quantity sensor 10A performs an N pole detection operation to detect the N pole side where the magnetic flux density B<0. When the magnetic flux density B changes in the direction of decreasing from the S pole side to the N pole side, it is not detected on the S pole side and the output voltage OUT remains at the H level. Further, when the magnetic flux density B decreases and the magnetic flux density B changes to the N pole side and falls below the magnetic flux density BOPN which is the N pole side operating point (B<BOPN<0), the physical quantity sensor 10A transitions to the N pole detection state for detecting the magnetic flux density B of the N pole, and the output voltage OUT changes from the H level to the L level. On the other hand, when the magnetic flux density B changes in the direction of increasing from the N pole side to the S pole side, the output voltage OUT remains at the L level even if the magnetic flux density B exceeds the magnetic flux density BOPN, but when the magnetic flux density B exceeds the magnetic flux density BRPN (<0) which is the N pole return point, the N pole detection state is released and the output voltage OUT changes from the L level to the H level.

[0017] FIG. 3 is a timing diagram showing the operation of the physical quantity sensor 10A. FIG. 3 includes five graphs with the time t on the horizontal axis, and in order from the top, represents the relationships of the consumption current, input signal IN, operation trigger signal TRIG, magnetic flux density B, and output voltage OUT with respect to the time t. The input signal IN and the magnetic flux density B shown in FIG. 3 are set as an example for explaining the operation timing of the physical quantity sensor 10A. Here, as illustrated in FIG. 3, the operation of the physical quantity sensor 10A when the input signal IN and the magnetic flux density B change respectively will be explained. Also, at time t = 0 which is the intersection with the vertical axis, it is assumed that the physical quantity sensor 10A is in a released state where it is performing an S-pole detection operation but not detecting the pole. The operation timing of the physical quantity sensor 10A (FIG. 3) will be explained in sequence starting from time t = 0. During the first pause period (the leftmost side in the uppermost graph of FIG. 3), that is, before the start of the first operation period after time t = 0, the state of the physical quantity sensor 10A at time t = 0 (hereinafter referred to as the "initial state") is maintained. That is, the output voltage OUT remains at the H level. This is because during the pause period, regardless of the presence or absence of a change in the magnetic flux density B, the detection state or the released state does not change.

[0018] When the first pause period ends, the first operation period starts. In the first operation period, since the input signal IN is at the L logic (IN = "L"), the physical quantity sensor 10A maintains the S-pole detection operation. Also, the magnetic flux density B exceeds the magnetic flux density BOPS upward (B > BOPS). When the first operation period of the physical quantity sensor 10A during the S-pole detection operation ends and the second pause period starts, it changes from the released state to the S-pole detection state, and the output voltage OUT changes from the H level to the L level. During the second pause period, the magnetic flux density B decreases and changes to a level where it exceeds the magnetic flux density BOPN downward (B < BOPN). However, during the pause period, since the detection state or the released state of the physical quantity sensor 10A does not change, the S-pole detection state of the physical quantity sensor 10A is maintained, and the output voltage OUT remains at the L level.

[0019] When the second operation period following the second pause period starts, the input signal IN is at the L logic, and since the magnetic flux density B exceeds the magnetic flux density BOPN downward, it exceeds the magnetic flux density BRPS (not shown in FIG. 3) serving as the S - pole side return point downward. Thus, in the second operation period, since the condition that the input signal IN is at the L logic and the magnetic flux density B exceeds the magnetic flux density BRPS downward (B < BRPS) is satisfied, when the second operation period ends and the third pause period starts, the physical quantity sensor 10A changes from the S - pole detection state to the release state, and the output voltage OUT changes from the L level to the H level. During the third pause period and before the trigger signal TRIG is supplied to the intermittent drive control circuit 22, the release state is maintained, and the output voltage OUT remains at the H level.

[0020] When the logic of the input signal IN changes from the L logic to the H logic during the third pause period, the input logic change detection circuit 21 detects the change in the logic of the input signal IN and outputs the operation trigger signal TRIG. The intermittent drive control circuit 22 that receives the operation trigger signal TRIG outputs the intermittent drive control signal Sco to the physical quantity detection circuit 23, and forcibly transitions the physical quantity sensor 10A from the pause period to the operation period. Hereinafter, the operation period forcibly started with the operation trigger signal TRIG as a trigger is referred to as the "trigger operation period". At the start of the first trigger operation period (the left - most trigger operation period in FIG. 3), since the logic of the input signal IN is the H logic, the physical quantity sensor 10A performs the N - pole detection operation. At the start of the first trigger operation period, since the physical quantity sensor 10A performs the N - pole detection operation and the condition that the magnetic flux density B exceeds the magnetic flux density BOPN downward (B < BOPN) is satisfied, when the first trigger operation period ends and the fourth pause period starts, the physical quantity sensor 10A becomes in the N - pole detection state, and the output voltage OUT becomes the L level. During the fourth pause period, the magnetic flux density B rises and exceeds the magnetic flux density BRPN (not shown in FIG. 3) which is the N-pole return point, and then transitions to a level that exceeds the magnetic flux density BOPS (B>BOPS). However, during the pause period, the detection state or release state of the physical quantity sensor 10A does not change, so the N-pole detection state is maintained and the output voltage OUT remains at the L level.

[0021] When the fourth idle period ends and the third operation period begins, as described above, the magnetic flux density B exceeds the magnetic flux density BRPN to the upper side. When the third operation period begins, the input signal IN is at H logic, satisfying the condition that the magnetic flux density B exceeds the magnetic flux density BRPN to the upper side (B>BRPN). Therefore, when the third operation period ends and the fifth idle period begins, the physical quantity sensor 10A changes from the N pole detection state to the release state, and the output voltage OUT changes from the L level to the H level.

[0022] During the fifth pause period and before the trigger signal TRIG is supplied to the intermittent drive control circuit 22, the release state of the physical quantity sensor 10A is maintained, and the output voltage OUT remains at the H level. When the logic of the input signal IN changes from logic H to logic L during the fifth idle period, the input logic change detection circuit 21 detects the change in the logic of the input signal IN and outputs an operation trigger signal TRIG. Upon receiving the operation trigger signal TRIG, the intermittent drive control circuit 22 outputs an intermittent drive control signal Sco to the physical quantity detection circuit 23, and forcibly transitions the physical quantity sensor 10A from the idle period to the operation period. In other words, the second trigger operation period begins. At the start of the second trigger operation period, the input signal IN is at logical L, so the physical quantity sensor 10A is in S pole detection operation. Also, the magnetic flux density B is maintained at a level that exceeds the magnetic flux density BOPS (B>BOPS). At the start of the second trigger operation period, the input signal IN is at logical L, and the condition that the magnetic flux density B exceeds the magnetic flux density BOPS is met. Therefore, at the end of the second trigger operation period and the start of the sixth pause period, the physical quantity sensor 10A changes from the release state to the S pole detection state, and the output voltage OUT changes from the H level to the L level. During the sixth pause period, the state in which the physical quantity sensor 10A detects the south pole is maintained, and the output voltage OUT remains at the L level.

[0023] As described above, physical quantity sensor 10A and semiconductor device 1A of this embodiment are configured so that input terminal 13, which is one of the four terminals, can switch the sensing pole and start the trigger operation period, thereby realizing the function of starting the trigger operation period without providing a separate enable terminal. Furthermore, physical quantity sensor 10A and semiconductor device 1A can be configured in a four-terminal package without compromising the function of starting the trigger operation period, so that the inspection time in the inspection process can be shortened at lower cost than conventional methods.

[0024] (Second embodiment) FIG. 4 is a block diagram showing a semiconductor device 1B including a physical quantity sensor 10B according to a second embodiment of the present invention. The semiconductor device 1B differs from the semiconductor device 1A in that it includes a physical quantity sensor 10B instead of the physical quantity sensor 10A, but is otherwise substantially the same. Furthermore, the physical quantity sensor 10B differs from the physical quantity sensor 10A in that it further includes a multi-value input circuit 25, but is otherwise substantially the same. Therefore, in this embodiment, the multi-value input circuit 25 will be mainly described, and from this embodiment onward, in the description of the physical quantity sensor 10B and the semiconductor device 1B, components that are substantially the same as those in the physical quantity sensor 10A and the semiconductor device 1A will be assigned the same reference numerals and will not be described again.

[0025] The multi-value input circuit 25 is provided between the input terminal 13 and the input logic change detection circuit 21. The multi-value input circuit 25 and the input logic change detection circuit 21 are connected via a signal line capable of transmitting a signal of 2 or more bits. The multi-value input circuit 25 supplies the input logic change detection circuit 21 with an encoded signal Sen including three or more different logic values ​​based on the input signal IN input from the input terminal 13.

[0026] Next, the operation of the physical quantity sensor 10B according to the second embodiment of the present invention will be described using the physical quantity sensor 10B including a ternary input circuit as the multi-value input circuit 25 as an example. The input signal IN supplied from the input terminal 13 is, for example, a signal including three-valued logic consisting of L, M, and H. For example, the physical quantity sensor 10B performs an S pole detection operation when the input signal IN is L logic, an omnipolar detection operation when it is M logic, and an N pole detection operation when it is H logic.

[0027] Here, the south pole detection operation, the omnipolar detection operation, and the north pole detection operation in the magnetic sensor serving as the physical quantity sensor 10B will be described. 5(A), 5(B), and 5(C) are characteristic diagrams showing the relationship between the magnetic flux density B and the output voltage OUT of a magnetic sensor serving as physical quantity sensor 10B, with the horizontal axis representing magnetic flux density B and the vertical axis representing output voltage OUT. 5(A), 5(B), and 5(C) respectively show the south pole detection operation, the omnipolar detection operation, and the north pole detection operation of the magnetic sensor.

[0028] Note that the S pole detection operation shown in FIG. 5(A) and the N pole detection operation shown in FIG. 5(C) are not substantially different from the S pole detection operation (FIG. 2(A)) and the N pole detection operation (FIG. 2(B)) in the magnetic sensor serving as the physical quantity sensor 10A, and therefore detailed explanations thereof will be omitted.

[0029] The bipolar detection operation shown in FIG. 5(B) is an operation in which the south pole detection operation shown in FIG. 5(A) and the north pole detection operation shown in FIG. 5(C) are superimposed, and therefore a detailed description thereof will be omitted.

[0030] Fig. 6 is a timing diagram showing the operation of the physical quantity sensor 10B. Like Fig. 3, Fig. 6 includes five graphs each showing the relationship of current consumption, input signal IN, operation trigger signal TRIG, magnetic flux density B, and output voltage OUT with respect to time t. The input signal IN and the magnetic flux density B shown in FIG. 6 are set as an example in explaining the operation timing of the physical quantity sensor 10B. Here, as illustrated in FIG. 6, the operation of the physical quantity sensor 10B when the input signal IN and the magnetic flux density B change respectively will be explained. Also, at time t = 0 which is the intersection point with the vertical axis, it is assumed that the physical quantity sensor 10B is in a released state where it is performing the S-pole detection operation but not detecting the pole. The operation timing of the physical quantity sensor 10B (FIG. 6) will be explained in sequence from time t = 0. During the first pause period, that is, before the start of the first operation period (the leftmost side in the uppermost graph of FIG. 6), since the initial state of the physical quantity sensor 10B is maintained, the output voltage OUT remains at the H level.

[0031] The output voltage OUT remains at the H level. When the first pause period ends, the first operation period starts. In the first operation period, since the input signal IN is at L logic (IN = “L”), the physical quantity sensor 10B maintains the S-pole detection operation. Also, the magnetic flux density B exceeds the magnetic flux density BOPS upward (B>BOPS). When the first operation period of the physical quantity sensor 10B during the S-pole detection operation ends and the second pause period starts, it changes from the released state to the S-pole detection state, and the output voltage OUT changes from the H level to the L level. During the second pause period, the magnetic flux density B decreases and changes to a level where it exceeds the magnetic flux density BOPN downward (B < BOPN). However, during the pause period, since the detection state or the released state of the physical quantity sensor 10B does not change, the S-pole detection state of the physical quantity sensor 10B is maintained, and the output voltage OUT remains at the L level.

[0032] When the second pause period ends and the second operation period starts, the input signal IN is at L logic, and since the magnetic flux density B exceeds the magnetic flux density BOPN downward, it exceeds the magnetic flux density BRPS (not shown in FIG. 6) that becomes the S - pole - side return point downward. Thus, in the second operation period, since the condition that the input signal IN is at L logic and the magnetic flux density B exceeds the magnetic flux density BRPS downward (B < BRPS) is satisfied, when the second operation period ends and the third pause period starts, the physical quantity sensor 10B becomes in the released state, and the output voltage OUT becomes at the H level. During the third pause period and before the trigger signal TRIG is supplied to the intermittent drive control circuit 22, the released state is maintained, and the output voltage OUT remains at the H level.

[0033] When the logic of the input signal IN changes from L logic to M logic (IN = “M”) during the third pause period and the input logic change detection circuit 21 detects the change in the logic of the input signal IN, it outputs the operation trigger signal TRIG. The intermittent drive control circuit 22 that receives the operation trigger signal TRIG outputs the intermittent drive control signal Sco to the physical quantity detection circuit 23, and forcibly transitions the physical quantity sensor 10B from the pause period to the operation period. At the start of the first trigger operation period (the left - most trigger operation period in FIG. 6), since the logic of the input signal IN has transitioned from L logic to M logic, the physical quantity sensor 10B performs the bipolar detection operation. Since the condition that the logic of the input signal IN is at M logic and the magnetic flux density B exceeds the magnetic flux density BOPN downward (B < BOPN) is satisfied, when the first trigger operation period ends and the fourth pause period starts, the physical quantity sensor 10B changes from the released state to the N - pole detection state, and the output voltage OUT changes from the H level to the L level. During the fourth rest period, the magnetic flux density B starts from a level exceeding the magnetic flux density BOPN downward, temporarily maintains this level, then increases at a certain rate, exceeds the magnetic flux density BRPN (not shown in FIG. 6), further exceeds the horizontal axis (magnetic flux density B = 0), and reaches a predetermined level (0 < B < BOPS) below the magnetic flux density BOPS and then maintains a constant level to end. However, during the rest period, since the detection state or release state of the physical quantity sensor 10B does not change, the output voltage OUT remains at the L level.

[0034] When the fourth rest period ends and the third operation period starts, as described above, the magnetic flux density B exceeds the magnetic flux density BRPN upward. At the time when the third operation period starts, the input signal IN is at M logic (IN = “M”) and the magnetic flux density B satisfies the condition of BOPS > B > BRPN. Therefore, when the third operation period ends and the fifth rest period starts, the physical quantity sensor 10B changes from the N - pole detection state to the release state, and the output voltage OUT changes from the L level to the H level. During the fifth rest period, the magnetic flux density B temporarily maintains a predetermined level (0 < B < BOPS) that exceeds the horizontal axis (magnetic flux density B = 0) and is below the magnetic flux density BOPS, then increases at a certain rate, and maintains a constant level when it reaches a predetermined level exceeding the magnetic flux density BOPS upward (B > BOPS). However, during the rest period, since the detection state or release state of the physical quantity sensor 10B does not change, the release state is maintained, and the output voltage OUT remains at the H level.

[0035] When the fifth idle period ends and the fourth operating period begins, the input signal IN is at M logic (IN="M") and the magnetic flux density B exceeds the magnetic flux density BOPS (B>BOPS). When the fourth operating period begins, the physical quantity sensor 10B, which is performing the omnipole detection operation, satisfies the condition that the magnetic flux density B exceeds the magnetic flux density BOPS (B>BOPS). Therefore, when the fourth operating period ends and the sixth idle period begins, the physical quantity sensor 10B changes from the released state to the S-pole detection state, and the output voltage OUT changes from the H level to the L level. During the sixth idle period and before the trigger signal TRIG is supplied to the intermittent drive control circuit 22, the S-pole detection state of the physical quantity sensor 10B is maintained, and the output voltage OUT remains at the L level.

[0036] When the input signal IN changes from M logic to H logic (IN="H") during the sixth idle period, the input logic change detection circuit 21 detects the change in logic of the input signal IN and outputs an operation trigger signal TRIG. Upon receiving the operation trigger signal TRIG, the intermittent drive control circuit 22 outputs an intermittent drive control signal Sco to the physical quantity detection circuit 23, and forcibly transitions the physical quantity sensor 10B from the idle period to the operation period. In other words, the second trigger operation period begins. At the start of the second trigger operation period, the input signal IN is at logic H, so the physical quantity sensor 10B is in north pole detection operation. Furthermore, the magnetic flux density B is maintained at a level that exceeds the magnetic flux density BOPS (B>BOPS). At the start of the second trigger operation period, the input signal IN is at logic H, and the condition that the magnetic flux density B exceeds the magnetic flux density BRPN (B>BRPN) is satisfied. Therefore, at the end of the second trigger operation period and the start of the seventh pause period, the physical quantity sensor 10B changes from the south pole detection state to the release state, and the output voltage OUT changes from the low level to the high level. During the seventh pause period, the magnetic flux density B decreases at a constant rate from a level exceeding the magnetic flux density BOPS upward, crosses the horizontal axis (magnetic flux density B = 0), and when it reaches a level exceeding the magnetic flux density BOPN downward (B < BOPN), it is maintained at a constant level. During the seventh pause period, the release state of the physical quantity sensor 10B is maintained, and the output voltage OUT remains at the H level.

[0037] When the seventh pause period ends and the fifth operation period starts, since the input signal IN is at the H logic (IN = “H”) and the magnetic flux density B exceeds the magnetic flux density BOPN downward (B < BOPN), when the fifth operation period ends and the eighth pause period starts, the physical quantity sensor 10B changes from the release state to the N-pole detection state, and the output voltage OUT changes from the H level to the L level. During the eighth pause period, the N-pole detection state is maintained, and the output voltage OUT remains at the L level.

[0038] As described above, according to the physical quantity sensor 10B and the semiconductor device 1B of the present embodiment, even if the input signal IN is a signal including a logic of three values or more such as a ternary value, the same effects as the physical quantity sensor 10A and the semiconductor device 1A can be obtained.

[0039] (Third Embodiment) FIG. 7 is a block diagram showing a physical quantity sensor 10C of the third embodiment of the present invention and a semiconductor device 1C including the physical quantity sensor 10C. The semiconductor device 1C is different from the semiconductor device 1B in that it includes a physical quantity sensor 10C instead of the physical quantity sensor 10B, but is substantially the same in other respects. Also, the physical quantity sensor 10C is different from the physical quantity sensor 10B in that it further includes a switch 26, but is substantially the same in other respects. Therefore, in the present embodiment, the switch 26 will be mainly described, and in the description of the physical quantity sensor 10C and the semiconductor device 1C, components that are substantially the same as those of the physical quantity sensor 10B and the semiconductor device 1B will be denoted by the same reference numerals as those of the physical quantity sensor 10B and the semiconductor device 1B, and the description thereof will be omitted.

[0040] The physical quantity sensor 10C differs from the physical quantity sensor 10B in that it further includes a two-input, one-output switch 26. A first input terminal of the switch 26 is connected to the input terminal 13. A second input terminal of the switch 26 is connected to the output terminal of the multi-value input circuit 25. An output terminal of the switch 26 is connected to the input terminal of the input logic change detection circuit 21.

[0041] Next, the operation of the physical quantity sensor 10C according to the third embodiment of the present invention will be described. In physical quantity sensor 10C, a switch 26 switches between a first path connecting input terminal 13 directly to input logic change detection circuit 21 and a second path connecting input terminal 13 to input logic change detection circuit 21 via multi-value input circuit 25. When switch 26 is switched to the first path, physical quantity sensor 10C is substantially the same as physical quantity sensor 10A. When switch 26 is switched to the second path, physical quantity sensor 10C is substantially the same as physical quantity sensor 10B. The operation of the circuits downstream from switch 26, i.e., input logic change detection circuit 21, intermittent drive control circuit 22, physical quantity detection circuit 23, and output driver 24, is the same as the input logic change detection circuit 21, intermittent drive control circuit 22, physical quantity detection circuit 23, and output driver 24 in physical quantity sensors 10A and 10B. With physical quantity sensor 10C and semiconductor device 1C, the path can be switched by switch 26, making it possible to alternatively select physical quantity sensor 10A and semiconductor device 1A, or physical quantity sensor 10B and semiconductor device 1B. Therefore, with physical quantity sensor 10C and semiconductor device 1C, it is possible to obtain the same effects as with physical quantity sensor 10A and semiconductor device 1A, or physical quantity sensor 10B and semiconductor device 1B, depending on the path selected.

[0042] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. In the implementation stage, various forms other than the above-described embodiments can be implemented, and various omissions, additions, substitutions, or modifications can be made without departing from the spirit of the invention. For example, in the above-described embodiments, a semiconductor device including a magnetic sensor as a physical quantity sensor was described as an example, but the physical quantity sensor is not limited to a magnetic sensor. In this embodiment, the physical quantity sensor may be various sensor elements capable of detecting physical quantities having polarity (or direction) other than magnetism, such as pressure, speed, acceleration, and voltage. Furthermore, the multi-value input circuit connected to the input terminal is not limited to a ternary input circuit. It may also be a multi-value input circuit that supports four or more different values.

[0043] These embodiments and their variations are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0044] 1A Semiconductor device (first embodiment) 1B Semiconductor Device (Second Embodiment) 1C Semiconductor device (third embodiment) 2. Semiconductor substrate 10A Physical quantity sensor (first embodiment) 10B Physical quantity sensor (second embodiment) 10C Physical Quantity Sensor (Third Embodiment) 11 1st power terminal 12 2nd power terminal 13 Input terminal 14 Output terminal 21 Input logic change detection circuit 22 Intermittent drive control circuit 23 Physical quantity detection circuit 24 output drivers 25 Multi-value input circuit 26 Switch

Claims

1. a first power supply terminal; a second power supply terminal; An input terminal, An output terminal; an input logic change detection circuit that detects the logic of a signal input via the input terminal and outputs a polarity switching signal corresponding to the detected logic, and that outputs an operation trigger signal when it detects a change in the logic of the input signal; a physical quantity detection circuit that detects a physical quantity of a polarity corresponding to the logic of the polarity switching signal and outputs a physical quantity detection signal corresponding to the detected physical quantity; an intermittent drive control circuit that causes the physical quantity detection circuit to intermittently alternate between an operating period and a pause period at a predetermined cycle, and that outputs an intermittent drive control signal that transitions the pause period to the operating period in response to the operation trigger signal; an output driver that receives the physical quantity detection signal and outputs an output signal to the output terminal; A physical quantity sensor comprising:

2. 2. The physical quantity sensor according to claim 1, further comprising a multi-value input circuit provided between the input terminal and the input logic change detection circuit, the multi-value input circuit supplying an encoded signal having different multi-values ​​in the logic to the input logic change detection circuit based on a signal input from the input terminal.

3. 3. The physical quantity sensor according to claim 2, further comprising a switch capable of switching either a signal input from the input terminal or a signal output from the multi-value input circuit to a signal to be supplied to the input logic change detection circuit.

4. A semiconductor device comprising the physical quantity sensor according to claim 1 .

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