JP7062935B2 - Current sensor, current sensor manufacturing method and semiconductor device - Google Patents

Description

The present invention relates to a semiconductor device, particularly a current sensor used in a power semiconductor module, a method for manufacturing the same, and a semiconductor device including the current sensor.

In Patent Document 1, a substrate on which a semiconductor element is mounted, an external terminal fixed to a surface on the substrate on which the semiconductor element is mounted, and an external terminal fixed to the surface on the substrate on which the semiconductor element is mounted are provided so as to face each other. A wiring pattern electrically connected to the main electrode of a semiconductor element, a first printed circuit board having a first through hole into which the external terminal is inserted, and a surface of the first printed circuit board on which the wiring pattern is provided face each other. A second printed circuit board having a magnetic sensor mounted on a surface facing the wiring pattern and a second through hole into which the external terminal is inserted, and the first printed circuit board and the second printed circuit board. A semiconductor device (power semiconductor module) including a support provided between the first printed circuit boards and a support for maintaining the space between the first printed circuit board and the second printed circuit board at regular intervals is described. In such a semiconductor device, an overcurrent can be detected and a soft shutdown can be performed at high speed.

Japanese Unexamined Patent Publication No. 2017-168721

In the semiconductor device according to Patent Document 1, the current is generated by two magnetic sensors (first sensor 20A and second sensor 20B) having a circuit system shown by an equivalent circuit shown in FIG. 2 and each having a full bridge circuit. The current Id flowing through the path 16b ₀ is detected. Since these two magnetic sensors (first sensor 20A and second sensor 20B) have improved noise immunity by decoupling, the control system configured to protect the operation in the event of overcurrent erroneously controls the operation. The risk of soft shutdown of semiconductor devices is appropriately suppressed.

The present invention is a current sensor that can be installed in a semiconductor device or the like in order to realize operation protection at the time of overcurrent as described above, and is a current sensor capable of stably measuring current changes such as overcurrent. It is an object of the present invention to provide a semiconductor device including the manufacturing method thereof and the current sensor.

The current sensor according to one aspect of the present invention provided to solve the above problems is a first sensor having a plurality of measurement magnetic-electric conversion elements and having a bridge circuit, and a bridge having a plurality of decoupling magnetic-electric conversion elements. A second sensor having a circuit is provided, and the plurality of measurement magnetic-electric conversion elements and the plurality of decoupling magnetic-electric conversion elements are all arranged in a direction along the first direction, which is the current flow direction of the current path. Each of the plurality of measurement magnetic / electrical conversion elements is arranged so as to be adjacent to the corresponding decoupling magnetic / electrical conversion element in the bridge circuit along the first direction.

The plurality of measurement magnetic-electric conversion elements and the plurality of decoupling magnetic-electric conversion elements are all arranged side by side in the direction along the first direction, and the corresponding measurement magnetic-electric conversion element and the decoupling magnetic-electric conversion element are arranged in the bridge circuit. Since they are arranged so as to be adjacent to each other, the measurement magnetic-electric conversion element and the decoupling magnetic-electric conversion element are arranged alternately (every other) in the first direction. The induced magnetic field of the current flowing through the current path is applied to the first sensor and the second sensor, but since the two sensors are arranged as described above, the applied states of the induced magnetic fields in the two sensors are equal to each other. The output signal of the current sensor obtained by the difference between the output signal of the first sensor and the output signal of the second sensor is less likely to contain a noise component. From the viewpoint of improving the detection accuracy, the bridge circuit is preferably a full bridge circuit. In this case, the first sensor is provided with four measurement magnetic and electrical conversion elements, and the second sensor is equipped with four decoupling magnetic and electrical conversion elements. Equipped with an element.

In the above current sensor, the first wiring that connects the plurality of measurement magnetic / electrical conversion elements of the first sensor to form the bridge circuit and the plurality of decoupling magnetic / electrical conversion elements of the second sensor are connected. When the second wiring constituting the bridge circuit has a portion symmetrically arranged with the line along the first direction interposed therebetween, the electromagnetic noise received by the first wiring and the second wiring are generated. It tends to be equal to the received electromagnetic noise, and it is difficult for the output signal of the current sensor to include a noise signal.

In the above current sensor, a shield that attenuates the strength of the induced magnetic field of the current in the current path may be arranged between the first sensor and the second sensor and the current path. In this case, it is preferable that the first wiring and the second wiring have a portion having a narrower line width than a portion located in the region facing the shield other than the region facing the shield. By providing such a configuration, it is possible to reduce the parasitic capacitance generated between the shield and the wiring (first wiring, second wiring).

When the shield is arranged, the wiring for applying the drive voltage of the measurement magnetic / electrical conversion element in the first wiring may include a portion located outside the region facing the shield. ..

As another aspect of the present invention, the present invention comprises a first sensor having a plurality of magnetic and electrical conversion elements for measurement and having a bridge circuit, and a second sensor having a plurality of decoupling magnetic and electrical conversion elements and having a bridge circuit. Provide a manufacturing method. In such a manufacturing method, the plurality of measurement magnetic-electric conversion elements and the plurality of decoupling magnetic-electric conversion elements are all arranged side by side in a direction along a first direction which is a current flow direction of the current path, and the plurality of said. Each of the measurement magnetic-electric conversion elements of the above is arranged so as to be adjacent to the corresponding decoupling magnetic-electric conversion element in the bridge circuit along the first direction, and the plurality of measurement magnetic-electric conversion elements and the plurality of The decoupling magnetic-electric conversion element is manufactured by the same manufacturing process, and the plurality of measurement magnetic-electric conversion elements and the plurality of decoupling magnetic-electric conversion elements are covered with the same resin package. In this way, by manufacturing the measurement magnetic-electric conversion element and the decoupling magnetic-electric conversion element by the same manufacturing process, the magnetic-electric conversion in the magnetic-electric conversion element (measurement magnetic-electric conversion element, decoupling magnetic-electric conversion element) included in the current sensor. There is less variation in characteristics. Therefore, the noise component included in the output signal of the first sensor can be appropriately removed by using the output signal of the second sensor.

The present invention, as another aspect, is a semiconductor device including the above-mentioned current sensor.

INDUSTRIAL APPLICABILITY According to the present invention, a current sensor capable of stably measuring a current change such as an overcurrent, a method for manufacturing the same, and a semiconductor device including the current sensor are provided.

It is a circuit diagram of the current sensor which concerns on one Embodiment of this invention. It is an equivalent circuit of the circuit system of the semiconductor device which is an example of the device provided with the current sensor which concerns on one Embodiment of this invention. It is a figure which shows the relationship between the element unit part of the current sensor which concerns on one Embodiment of this invention, and a current path. It is a graph which shows the measurement result by the current sensor which concerns on one Embodiment of this invention. It is a graph which shows the measurement result by the current sensor which concerns on patent document 1. FIG.

Hereinafter, the current sensor according to the embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a circuit diagram of a current sensor according to an embodiment of the present invention. FIG. 2 is an equivalent circuit of a circuit system of a semiconductor device, which is an example of a device including a current sensor according to an embodiment of the present invention.

As shown in FIG. 1, the current sensor 10 according to the present embodiment has an element unit unit 20 including two sensors (first sensor 20A and second sensor 20B) each having a full bridge circuit, and an element unit unit 20. Differential amplifiers (first differential amplifier 21A, second differential amplifier 21B) that input the output signal from each full bridge circuit of the above, and these differential amplifiers (first differential amplifier 21A, second differential amplifier 21A, second differential amplifier). A third differential amplifier 23 that receives an output signal from the amplifier 21B) as an input is provided.

The element unit unit 20 includes a first sensor 20A and a second sensor 20B. In the first sensor 20A, a half bridge in which two measurement magnetic and electrical conversion elements 22Aa and 22Ab are connected in series and a half bridge in which two measurement magnetic and electrical conversion elements 22Ac and 22Ad are connected in series are input. It is connected in parallel between the terminal VddA and the ground terminal GND. The four measuring magnetoelectric conversion elements 22Aa to 22Ad are composed of a magnetoresistive effect element having a meander structure. The four measurement magnetic-electric conversion elements 22Aa to 22Ad have the same direction of the sensitivity axis (the sensitivity axis is indicated on each element by a white arrow in FIG. 3), but the measurement magnetic-electric conversion element 22Aa and the measurement magnetic-electric conversion In the element 22Ac, the direction of the sensitivity axis is also the same, whereas in the measurement magnetic-electric conversion element 22Ab and the measurement magnetic-electric conversion element 22Ad, the sensitivity axis is opposite to that of the measurement magnetic-electric conversion element 22Aa (see FIG. 3). Therefore, by inputting the intermediate potential VA1 of the two measurement magnetic and electrical conversion elements 22Aa and 22Ab and the intermediate potential VA2 of the two measurement magnetic and electrical conversion elements 22Ac and 22Ad into the first differential amplifier 21A, the first sensor 20A can be used. The output signal can be obtained from the first differential amplifier 21A.

The signal output from the first differential amplifier 21A includes not only the signal showing the measurement result by the four measurement magnetic and electrical conversion elements 22Aa, 22Ab, 22Ac, and 22Ad included in the first sensor 20A, but also noise such as environmental noise. The signal is also included. Therefore, the current sensor 10 according to the embodiment of the present invention includes the second sensor 20B so that noise can be removed. In the second sensor 20B, a half bridge in which two decoupling magnetic / electric conversion elements 22Ba and 22Bb are connected in series and a half bridge in which two decoupling magnetic / electric conversion elements 22Bc and 22Bd are connected in series are input. It is connected in parallel between the terminal VddB and the ground terminal GND. Here, the four measurement magnetic / electrical conversion elements 22Aa, 22Ab, 22Ac, 22Ad included in the first sensor 20A and the four decoupling magnetic / electrical conversion elements 22Ba, 22Bb, 22Bc, 22Bd included in the second sensor 20B are the same. It is preferably manufactured by a manufacturing process. Two magnetic and electrical conversion elements (specifically, a measurement magnetic and electrical conversion element 22Aa and a decoupling magnetic and electrical conversion element 22Ba, a measurement magnetic and electrical conversion element 22Ab and a decoupling magnetic and electrical conversion element 22Bb) corresponding to the first sensor 20A and the second sensor 20B. , The measuring magnetic electric conversion element 22Ac and the decoupling magnetic electric conversion element 22Bc, and the measuring magnetic electric conversion element 22Ad and the decoupling magnetic electric conversion element 22Bd) are manufactured by the same process, so that the magnetic and electric conversion characteristics of these elements can be made uniform. It is possible to remove noise more appropriately. Since the two corresponding magnetic / electric conversion elements in the first sensor 20A and the second sensor 20B are manufactured by the same process, the directions of the sensitivity axes of these two magnetic / electric conversion elements are the same.

A voltage such as 5V is input to the input terminal VddA of the first sensor 20A as a drive voltage, but no drive voltage is applied to the input terminal VddB of the second sensor 20B. Therefore, by inputting the intermediate potential VB1 of the two decoupling magnetic and electrical conversion elements 22Ba and 22Bb and the intermediate potential VB2 of the two decoupling magnetic and electrical conversion elements 22Bc and 22Bd in the second sensor 20B to the second differential amplifier 21B, A signal substantially equal to the noise signal included in the first differential amplifier 21A can be obtained as an output signal of the second differential amplifier 21B.

Therefore, by using the output signal of the first differential amplifier 21A and the output signal of the second differential amplifier 21B as the inputs of the third differential amplifier 23, only the signal indicating the measurement result of the first sensor 20A is the third difference. It can be obtained as the output of the dynamic amplifier 23.

As shown in FIG. 2, the element unit unit 20 is arranged, for example, in the vicinity of the current path 16b ₀ of the semiconductor device 100. The semiconductor device 100 of this embodiment is composed of a circuit including a semiconductor element, an input / output terminal, and a control terminal. The semiconductor element includes a switching element, and for example, a metal oxide semiconductor field effect transistor (PWM), an insulated gate bipolar transistor (IGBT), or the like can be adopted. Further, the semiconductor element may include a switching element and a diode element. Diodes can be connected to the switching element in antiparallel. When the semiconductor element is a MOSFET, the input / output terminals are the drain terminal and the source terminal, and the control terminal is the gate terminal. The voltage applied to the gate terminal controls the current Id flowing from the high potential drain terminal to the low potential source terminal. When the induced magnetic field of the current Id flowing through the current path 16b ₀ is applied to the magnetic and electric conversion elements (measurement magnetic and electric conversion elements 22Aa to 22Ad, decoupling magnetic and electric conversion elements 22Ba to 22Bd) of the element unit unit 20, the magnetic field strength is measured. By doing so, the current sensor 10 can measure the current value of the current path 16b ₀ and detect that an overcurrent has flowed in the current path 16b ₀ .

Hereinafter, the structure of the element unit unit will be described in detail with reference to FIG. FIG. 3 is a diagram showing the relationship between the element unit portion of the current sensor and the current path according to the embodiment of the present invention.

As described above, the element unit unit 20 includes a first sensor 20A having a bridge circuit including a plurality of measurement magnetic-electric conversion elements (specifically, four measurement magnetic-electric conversion elements 22Aa to 22Ad), and a plurality of decups. It includes a second sensor 20B having a ring magnetic / electrical conversion element (specifically, four decoupling magnetic / electrical conversion elements 22Ba to 22Bd) and a bridge circuit. Each of the plurality of measurement magnetic / electrical conversion elements 22Aa to 22Ad and the plurality of decoupling magnetic / electrical conversion elements 22Ba to 22Bd is the first direction D1 (Y1-Y2 in FIG. 3) which is the flow direction of the current Id in the current path 16b ₀ . It is arranged side by side in the direction along the direction). Further, each of the plurality of measurement magnetic / electrical conversion elements 22Aa to 22Ad is arranged so as to be adjacent to the corresponding decoupling magnetic / electrical conversion elements 22Ba to 22Bd in the bridge circuit along the first direction D1 (Y1-Y2 direction). To.

Therefore, the plurality of measurement magnetic / electrical conversion elements 22Aa to 22Ad and the plurality of decoupling magnetic / electrical conversion elements 22Ba to 22Bd are alternately arranged along the first direction D1 (Y1-Y2 direction). Specifically, as shown in FIG. 3, from the Y1 side in the Y1-Y2 direction, the decoupling magnetic-electric conversion element 22Ba, the measurement magnetic-electric conversion element 22Aa, the decoupling magnetic-electric conversion element 22Bb, the measurement magnetic-electric conversion element 22Ab, and the decup. The ring magnetic-electric conversion element 22Bc, the measurement magnetic-electric conversion element 22Ac, the decoupling magnetic-electric conversion element 22Bd, and the measurement magnetic-electric conversion element 22Ad are arranged along the first direction D1 (Y1-Y2 direction) in this order.

By being arranged in this way, the induced magnetic field of the current Id flowing through the current path _16b0 applied to each of the measurement magnetic and electrical conversion elements 22Aa to 22Ad constituting the bridge circuit of the first sensor 20A and the corresponding induced magnetic field thereof. Since the difference from the induced magnetic field of the current Id flowing through the current path 16b ₀ applied to the decoupling magnetic / electrical conversion elements 22Ba to 22Bd of the second sensor 20B is small, the output value from the second sensor 20B is the first sensor 20A. The value is close to the output value when no voltage is applied to the input terminal VddA of. Therefore, the output of the third differential amplifier 23 having the output from the first differential amplifier 21A and the output of the second differential amplifier 21B as inputs is brought closer to the true signal indicating the measurement result in the first sensor 20A. Will be realized.

The first wiring EL1 that connects the measurement magnetic and electric conversion elements 22Aa to 22Ad of the first sensor 20A to form a bridge circuit and the decoupling magnetic and electric conversion elements 22Ba to 22Bd of the second sensor 20B are connected to form a bridge circuit. The second wiring EL2 has a portion symmetrically arranged with a line Lc (indicated by a two-dot chain line in FIG. 3) along the first direction D1 (Y1-Y2 direction). Specifically, the second wiring EL2 of the second sensor 20B is moved to the Y2-Y2 direction Y2 side to the extent that it overlaps with the measurement magnetic-electric conversion elements 22Aa to 22Ad corresponding to each of the decoupling magnetic-electric conversion elements 22Ba to 22Bd. After that, it is formed so as to overlap with the first wiring EL1 of the first sensor 20A by rotating 180 degrees with the line Lc along the first direction D1 (Y1-Y2 direction) as the center line.

Since the first wiring EL1 and the second wiring EL2 are formed with high symmetry in this way, the noise picked up by the first wiring EL1 and the noise picked up by the second wiring EL2 tend to be equal to each other. Therefore, in the difference between the first wiring EL1 and the second wiring EL2, which are the output signals of the third differential amplifier 23, the noise component included in the output signal of the first differential amplifier 21A is likely to be efficiently removed.

From the viewpoint of simplifying the configuration of the first wiring EL1 of the first sensor 20A, the electrode portion EPA1 for the input terminal VddA connected to the measurement magnetic / electric conversion element 22Aa, the measurement magnetic / electric conversion element 22Aa, and the measurement magnetic / electric conversion element. Electrode part EPA2 for intermediate potential VA1 with 22Ab, electrode part EPA3 for ground terminal GND connected to magnetic and electric conversion element 22Ab for measurement and magnetic and electric conversion element 22Ac for measurement, and magnetic and electric conversion element 22Ac for measurement and measurement. The electrode portion EPA4 for the intermediate potential VA2 with the magnetic electric conversion element 22Ad is arranged along the first direction D1 (Y1-Y2 direction). The electrode portions (electrode portions EPB1 to EPB4) corresponding to these electrode portions (electrode portions EPA1 to EPA4) in the second wiring EL2 of the second sensor 20B are also the same as the electrode portions EPA1 to EPA4 in the first direction D1 (Y1). -It is arranged along the Y2 direction).

In the element unit unit 20 shown in FIG. 3, the strength of the induced magnetic field of the current Id of the current path 16b ₀ is attenuated so as to be located between the first sensor 20A and the second sensor 20B and the current path 16b ₀ . A shield (magnetic shield) 24 is arranged. In FIG. 3, since the shield 24 is arranged on the surface of the substrate SB on which the first sensor 20A and the second sensor 20B are arranged, which is opposite to the surface on which these sensors are arranged, the shield 24 is a broken line. Indicated by. The shield 24 is substantially rectangular, has a long axis in the direction along the flow direction of the current Id of the current path 16b ₀ (first direction D1 (Y1-Y2 direction)), and has a major axis of the current Id of the current path 16b ₀ . It has a minor axis in the direction along the application direction (X1-X2 direction) of the induced magnetic field. By arranging the shield 24 in this way, residual magnetization in the direction along the application direction (X1-X2 direction) of the induced magnetic field is less likely to occur in the shield 24 due to the shape magnetic anisotropy, which is preferable.

However, since parasitic capacitance may occur between the shield 24 and the wiring (first wiring EL1, second wiring EL2), the first wiring EL1 and the second wiring EL2 are in the region facing the shield 24. It is preferable to have a portion (narrow portion) ELN whose line width is narrower than that of a portion located outside the region facing the shield 24. In FIG. 3, such a narrow portion ELN is a portion between the measurement magnetic and electric conversion elements 22Aa to 22Ad and the electrode portions EPA1 to EPA4, and between the decoupling magnetic and electric conversion elements 22Ba to 22Bd and the electrode portions EPB1 to EPB4. Located in the part.

A relatively high voltage such as 5V is applied to the portion (wide portion) ELW to which the driving voltage of the measurement magnetic / electrical conversion elements 22Aa to 22Ad is applied in the first wiring EL1. Therefore, the wide portion ELW can be set to have a wide wiring width by including a portion located outside the region facing the shield 24. When the wiring width of the wide portion ELW of the first wiring EL1 is relatively wide as described above, the second wiring EL2 corresponds to the case where the wiring width of the first wiring EL1 and the second wiring EL2 is ensured to be high. It is preferable to widen the wiring width of the portion.

The method for manufacturing the current sensor 10 according to the embodiment of the present invention is not limited. As described above, it is preferable that the measuring magnetic-electric conversion elements 22Aa to 22Ad and the decoupling magnetic-electric conversion elements 22Ba to 22Bd are manufactured by the same manufacturing process. Further, from the viewpoint of facilitating uniform distortion applied to the magnetic / electric conversion element, it is preferable that the measurement magnetic / electric conversion elements 22Aa to 22Ad and the decoupling magnetic / electric conversion elements 22Ba to 22Bd are covered with the same resin package. .. Here, the material constituting the resin package may contain a component other than the resin, and inorganic particles such as silica are exemplified as such a component.

Although the present invention has been described with reference to the above embodiments, the present invention is not limited to the above embodiments, and can be improved or modified within the scope of the purpose of improvement or the idea of the present invention. In the above description, the magnetoelectric conversion element is a magnetoresistive effect element, but the present invention is not limited to this, and another magnetic / electric conversion element such as a Hall element may be used.

Hereinafter, the measurement results of the current sensor according to the embodiment of the present invention will be shown, and the effects of the present invention will be described in more detail.

A current sensor 10 including the element unit unit 20 having the structure shown in FIG. 3 is manufactured, and the element unit unit 20 is used for four measurements in the flow direction (first direction D1) of the current Id of the bus bar (current path 16b ₀ ). The magnetic-electric conversion elements 22Aa to 22Ad were arranged so as to be aligned with each other, and a predetermined current Id was passed through the bus bar (current path 16b ₀ ). The output of the first differential amplifier 21A, the output of the second differential amplifier 21B, and the output of the third differential amplifier 23 after the current Id was started to flow were measured. The measurement results and the theoretical values of the output of the third differential amplifier 23 are shown in Table 1 and FIG.

As shown in Table 1 and FIG. 4, a periodic signal derived from noise was superimposed on the output signal of the first differential amplifier 21A and the output signal of the second differential amplifier 21B. This periodic noise was appropriately removed from the output signal of the differential amplifier 23, and an output equal to the theoretical value was obtained several μS (microseconds) after the current Id was started to flow.

On the other hand, as shown in FIG. 6 of Patent Document 1, a current sensor in which two sensors (corresponding to the first sensor 20A and the second sensor 20B in the present invention) are arranged in a separated state is used. Similar measurements were made. The results are shown in Table 2 and FIG.

As shown in Table 2 and FIG. 5, the phase of the periodic noise included in the output signal of the first differential amplifier 21A and the phase of the periodic noise included in the output signal of the second differential amplifier 21B are out of phase. rice field. It is considered that this is because the positions of the two sensors included in the current sensor are separated from each other. When there is such a phase shift, even if the difference between the output signal of the first differential amplifier 21A and the output signal of the second differential amplifier 21B is obtained by the third differential amplifier 23, the third differential amplifier Periodic noise could not be completely removed from the output signal of 23, and a deviation from the theoretical value was observed.

10: Current sensor 16b ₀ : Current path 20: Element unit unit 20A: First sensor 20B: Second sensor 21A: First differential amplifier 21B: Second differential amplifier 22Aa: Measurement magnetic electric conversion element 22Ab: Measurement magnetic electric Conversion element 22Ac: Measurement magnetic electric conversion element 22Ad: Measurement magnetic electric conversion element 22Ba: Decoupling magnetic electric conversion element 22Bb: Decoupling magnetic electric conversion element 22Bc: Decoupling magnetic electric conversion element 22Bd: Decoupling magnetic electric conversion element 23: Third differential Amplifier 24: Shield 100: Semiconductor device D1: First direction EL1: First wiring EL2: Second wiring ELN: Narrow part ELW: Wide part EPA1: Electrode part EPA2: Electrode part EPA3: Electrode part EPA4: Electrode part EPB1: Electrode part EPB2: Electrode part EPB3: Electrode part EPB4: Electrode part GND: Ground terminal Id: Current SB: Substrate VA1: Intermediate potential VA2: Intermediate potential VB1: Intermediate potential VB2: Intermediate potential VddA: Input terminal VddB: Input terminal

Claims (6)

A first sensor that has a bridge circuit equipped with a plurality of magnetic and electrical conversion elements for measurement, and a drive voltage is applied to the bridge circuit during use .
It has a bridge circuit with a plurality of reference magnetic and electrical conversion elements, and has a second sensor to which a drive voltage is not applied to the bridge circuit during use .
It is a current sensor whose measurement target is the current path, which is the path of the current flowing from the high-potential terminal to the low-potential terminal of the semiconductor device .
The plurality of magnetic and electric conversion elements for measurement and the plurality of reference magnetic and electric conversion elements are all arranged side by side in a direction along a first direction which is a current flow direction of the current path at the time of use .
A current sensor, wherein each of the plurality of measurement magnetic / electrical conversion elements is arranged adjacent to the reference magnetic / electrical conversion element corresponding to the bridge circuit along the first direction. The bridge circuit by connecting the first wiring for connecting the plurality of measurement magnetic / electrical conversion elements of the first sensor to form the bridge circuit and the plurality of reference magnetic / electrical conversion elements of the second sensor. The current sensor according to claim 1, wherein the second wiring constituting the above-mentioned one has a portion symmetrically arranged with a line along the first direction interposed therebetween. A shield for attenuating the strength of the induced magnetic field of the current in the current path is arranged between the first sensor and the second sensor and the current path.
The current sensor according to claim 2 , wherein the first wiring and the second wiring have a portion having a narrower line width than a portion located in a region facing the shield other than the region facing the shield. The current sensor according to claim 3, wherein the portion of the first wiring for applying the drive voltage of the plurality of measurement magnetic / electrical conversion elements includes a portion located outside the region facing the shield. A first sensor that has a bridge circuit equipped with a plurality of magnetic and electrical conversion elements for measurement, and a drive voltage is applied to the bridge circuit during use .
It has a bridge circuit with a plurality of reference magnetic and electrical conversion elements, and has a second sensor to which a drive voltage is not applied to the bridge circuit during use .
It is a method of manufacturing a current sensor whose measurement target is a current path, which is a path of a current flowing from a high-potential terminal to a low-potential terminal of a semiconductor device .
The plurality of magnetic and electric conversion elements for measurement and the plurality of reference magnetic and electric conversion elements are all arranged side by side in a direction along a first direction which is a current flow direction of the current path at the time of use .
Each of the plurality of measurement magnetic / electrical conversion elements is arranged so as to be adjacent to the corresponding reference magnetic / electrical conversion element in the bridge circuit along the first direction.
The plurality of magnetic and electrical conversion elements for measurement and the plurality of reference magnetic and electrical conversion elements are manufactured by the same manufacturing process.
A method for manufacturing a current sensor, wherein the plurality of magnetic / electrical conversion elements for measurement and the plurality of reference magnetic / electrical conversion elements are covered with the same resin package. A semiconductor device comprising the current sensor according to any one of claims 1 to 4 and the current path , wherein the current sensor can measure a current flowing through the current path .

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