Current sensor

Abstract

The invention provides a current sensor. This current sensor is provided with a first lead frame, a signal processing IC, a first magnetoelectric conversion element, a second magnetoelectric conversion element, and a second lead frame that partially surrounds the first magnetoelectric conversion element and the second magnetoelectric conversion element. In a plan view, the first magnetoelectric conversion element and the second magnetoelectric conversion element may be disposed so as to face each other with an intermediate portion, which is a part of the second lead frame, interposed therebetween, and the intermediate portion causes a current to flow in a second direction intersecting a first direction from the first magnetoelectric conversion element toward the second magnetoelectric conversion element. The plurality of first wires may be electrically connected to the signal processing IC so as to extend in a direction different from the second magnetoelectric conversion element side in plan view and so as not to traverse the second lead frame. The plurality of second wires may be electrically connected to the signal processing IC so as to extend in a direction different from the first magnetoelectric conversion element side in plan view and so as not to traverse the second lead frame.

Description

Technical Field

[0001] The present invention relates to a current sensor. Background Art

[0002] Patent document 1 describes "a current sensor comprising: a primary conductor having an opening extending from an upper surface to a lower surface and through which a current to be measured flows; a lead frame electrically separated from the primary conductor and having a portion overlapping with the opening of the primary conductor; and a magnetic sensor provided on the lead frame at a position overlapping with the opening of the primary conductor and detecting the current to be measured."

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-036237 Summary of the invention

[0006] Problems to be solved by the invention

[0007] In a primary conductor having a shape like that of Patent Document 1, the current is divided into two paths and flows in the same direction, so the magnetic field penetrating the magnetic sensor may not be effectively increased. As a result, the sensitivity of the magnetic sensor may not be improved, and the S / N ratio may not be effectively improved.

[0008] Means for solving problems

[0009] A current sensor according to one embodiment of the present invention may include a first lead frame having a first terminal portion. The current sensor may include a signal processing IC, the second surface of which is supported on the first surface of the first lead frame, and the signal processing IC is electrically connected to the first lead frame. The current sensor may include a first magnetoelectric conversion element and a second magnetoelectric conversion element, which are independently configured from the signal processing IC, are mounted on the first surface of the signal processing IC on the side opposite to the second surface, and output a signal to be processed by the signal processing IC to the signal processing IC. The current sensor may include a second lead frame, which has a second terminal portion opposite to the first terminal portion when viewed from above, at least a portion of the second lead frame is arranged opposite to the first surface of the signal processing IC, and the second lead frame partially surrounds the first magnetoelectric conversion element and the second magnetoelectric conversion element when viewed from above, and a measurement current to be measured by the first magnetoelectric conversion element and the second magnetoelectric conversion element flows through the second lead frame. When viewed from above, the first magnetoelectric conversion element and the second magnetoelectric conversion element can be arranged relative to each other with an intermediate portion as a part of the second lead frame sandwiched therebetween, and the intermediate portion allows current to flow in a second direction intersecting the first direction, the first direction being a direction from the first magnetoelectric conversion element toward the second magnetoelectric conversion element. The first magnetoelectric conversion element can be electrically connected to the signal processing IC via a plurality of first wires. The plurality of first wires can be electrically connected to the signal processing IC in a manner that extends in a direction different from the second magnetoelectric conversion element side when viewed from above and does not cross the second lead frame. The second magnetoelectric conversion element can be electrically connected to the signal processing IC via a plurality of second wires. The plurality of second wires can be electrically connected to the signal processing IC in a manner that extends in a direction different from the first magnetoelectric conversion element side when viewed from above and does not cross the second lead frame.

[0010] In the current sensor, the second terminal portion may have a pair of terminals. The second lead frame may have: a first portion extending from one of the pair of terminals to the first terminal portion side; a second portion extending from the other of the pair of terminals to the first terminal portion side; and a connecting portion connecting the end of the second portion to the end of the first portion. The first magnetoelectric conversion element may be surrounded by the first portion, the connecting portion, and the second portion when viewed from above. The middle portion may be the second portion or the connecting portion. The distance between the first magnetoelectric conversion element and the middle portion may be shorter than the distance between the first magnetoelectric conversion element and the second lead frame in the second direction. The distance between the second magnetoelectric conversion element and the middle portion may be shorter than the distance between the second magnetoelectric conversion element and the second lead frame in the second direction.

[0011] In any of the current sensors, it may be that the second lead frame also has: a first extension portion, when the second portion is the middle portion, only one side of the first extension portion is joined to the connecting portion or the other terminal of the pair of terminals, when the connecting portion is the middle portion, only one side of the first extension portion is joined to the first portion, and the first extension portion is adjacent to the second magneto-electric conversion element; and a second extension portion, only one side of the second extension portion is joined to the first extension portion, the second extension portion is not joined to other parts of the second lead frame, and is adjacent to the second magneto-electric conversion element.

[0012] In any of the above current sensors, the width of the intermediate portion in the first direction may be equal to or smaller than the width of the first portion in a direction intersecting a direction in which the measurement current flows.

[0013] In any of the current sensors, when the intermediate portion is the second portion, the first direction may be a direction intersecting a direction connecting the second terminal portion and the first terminal portion.

[0014] In any of the current sensors, a width of the connecting portion in the second direction may be less than a width of the first portion in the first direction.

[0015] In any of the current sensors, the width of the signal processing IC in a direction from the second terminal portion toward the first terminal portion may be longer than the width of the signal processing IC in a direction intersecting the direction from the second terminal portion toward the first terminal portion when viewed from above.

[0016] In any of the above current sensors, the first lead frame may have an end surface on an imaginary line passing through the centers of the first magneto-electric transducer element and the second magneto-electric transducer element in a plan view.

[0017] In any of the current sensors, it may be that, when the distance between the center of the first magnetoelectric conversion element and the center of the second magnetoelectric conversion element is set to L and the thickness of the second lead frame is set to Ta, the distance H in the thickness direction between the signal processing IC and the second lead frame satisfies 0.01 mm. <H<3×L-0.5×Ta。

[0018] In any of the current sensors, when the widths of the first magnetoelectric transducer and the second magnetoelectric transducer in the first direction are denoted as Wb, 0.5×Ta+Wb may be satisfied. <L。

[0019] In any of the current sensors, when the height from the first surface of the signal processing IC to the magnetically sensitive surfaces of the first magnetoelectric transducer element and the second magnetoelectric transducer element is set to Tb and the width in the first direction is set to Wb, Tb≤3×Wb may be satisfied.

[0020] In any of the above current sensors, H≤3×Wb+0.5×Ta may be satisfied.

[0021] In any of the above current sensors, the first lead frame may include a first step portion that is a portion that is recessed in a direction away from the second lead frame in a thickness direction while supporting a portion that supports the signal processing IC.

[0022] In any of the above current sensors, the second lead frame may include a second step portion that is a portion that faces the signal processing IC and projects in a direction away from the signal processing IC in a thickness direction.

[0023] In any of the current sensors, the second step portion may protrude in the thickness direction relative to the second terminal portion by an amount greater than 0 times and not more than 0.6 times the thickness of the second lead frame.

[0024] In any of the current sensors, the wiring included in the top layer of the first surface side of the signal processing IC may be arranged at a position that does not overlap with the first magnetoelectric conversion element and the second magnetoelectric conversion element in the thickness direction, or the wiring included in the top layer of the first surface side of the signal processing IC may be arranged at a position that overlaps with the first magnetoelectric conversion element and the second magnetoelectric conversion element in the thickness direction and has a width that overlaps the entirety of the first magnetoelectric conversion element and the second magnetoelectric conversion element when viewed from above.

[0025] Any of the current sensors may further include a sealing portion, which uses a molded resin to seal a portion of the first lead frame other than the exposed portion of the first terminal portion, a portion of the second lead frame other than the exposed portion of the second terminal portion, the signal processing IC, the first magnetoelectric conversion element, and the second magnetoelectric conversion element in a state in which the second lead frame is separated from the first lead frame, the signal processing IC, the first magnetoelectric conversion element, and the second magnetoelectric conversion element.

[0026] In any of the current sensors, the first height may be the same as the second height, or the first height may be lower than the second height, the first height being the height of the first terminal portion at a position where the first side surface intersects with the first side surface on the same side as the first side of the signal processing IC in the thickness direction of the sealing portion, the first side surface being the surface of the sealing portion through which the first terminal portion is exposed, and the second height being the height of the second terminal portion at a position where the second side surface intersects with the second side surface on the same side as the second side of the signal processing IC in the thickness direction of the sealing portion, and the second side surface being the surface of the sealing portion through which the second terminal portion is exposed.

[0027] The first magnetoelectric conversion element, the second magnetoelectric conversion element and the middle part may be rectangular when viewed from above. When viewed from above, there may be no wires or elements in each area between the side surfaces of the first magnetoelectric conversion element and the second magnetoelectric conversion element that are opposite to the middle part and the side surfaces of the middle part that are opposite to the first magnetoelectric conversion element and the second magnetoelectric conversion element, respectively.

[0028] A current sensor according to one embodiment of the present invention may include a lead frame having a first terminal portion. The current sensor may include a signal processing IC, the second surface of which is supported on the first surface of the first lead frame, and the signal processing IC is electrically connected to the first lead frame. The current sensor may include a first magnetoelectric conversion element and a second magnetoelectric conversion element, which are independently configured from the signal processing IC, are mounted on the first surface of the signal processing IC on the side opposite to the second surface, and output a signal to be processed by the signal processing IC to the signal processing IC. The current sensor may include a second lead frame, which has a second terminal portion opposite to the first terminal portion when viewed from above, at least a portion of the second lead frame is arranged opposite to the first surface of the signal processing IC, and the second lead frame partially surrounds the first magnetoelectric conversion element and the second magnetoelectric conversion element when viewed from above, and a measurement current to be measured by the first magnetoelectric conversion element and the second magnetoelectric conversion element flows through the second lead frame. In a plan view, the first magnetoelectric conversion element and the second magnetoelectric conversion element may be arranged opposite to each other with an intermediate portion as a part of the second lead frame sandwiched therebetween, the intermediate portion allowing current to flow in a second direction intersecting the first direction, the first direction being a direction from the first magnetoelectric conversion element toward the second magnetoelectric conversion element. The first magnetoelectric conversion element may be electrically connected to the signal processing IC via a plurality of first wires that do not cross the second lead frame. The second magnetoelectric conversion element may be electrically connected to the signal processing IC via a plurality of second wires that do not cross the second lead frame. The second terminal portion may have a pair of terminals. The second lead frame may have: a first portion extending from one of the pair of terminals to the first terminal portion side; a second portion extending from the other of the pair of terminals to the first terminal portion side; and a connecting portion connecting the end of the second portion to the end of the first portion. The first magnetoelectric conversion element may be surrounded by the first portion, the connecting portion, and the second portion in a plan view. The intermediate portion may be the second portion or the connecting portion. The distance between the first magnetoelectric transducer and the middle portion may be shorter than the distance between the first magnetoelectric transducer and the second lead frame in the second direction. The distance between the second magnetoelectric transducer and the middle portion may be shorter than the distance between the second magnetoelectric transducer and the second lead frame in the second direction.

[0029] In the current sensor, when the middle portion is the second portion, the width of the middle portion in the first direction may be less than the width of the connecting portion in the second direction. When the middle portion is the connecting portion, the width of the middle portion in the first direction may be less than the width of the second portion in the second direction.

[0030] A current sensor according to one embodiment of the present invention may include a first lead frame having a first terminal portion. The current sensor may include a signal processing IC, the second surface of which is supported on the first surface of the first lead frame, and the signal processing IC is electrically connected to the first lead frame. The current sensor may include a first magnetoelectric conversion element and a second magnetoelectric conversion element, which are independently configured from the signal processing IC, are mounted on the first surface of the signal processing IC on the side opposite to the second surface, and output a signal to be processed by the signal processing IC to the signal processing IC. The current sensor may include a second lead frame, which has a second terminal portion opposite to the first terminal portion when viewed from above, at least a portion of the second lead frame is arranged opposite to the first surface of the signal processing IC, and the second lead frame partially surrounds the first magnetoelectric conversion element and the second magnetoelectric conversion element when viewed from above, and a measurement current to be measured by the first magnetoelectric conversion element and the second magnetoelectric conversion element flows through the second lead frame. When viewed from above, the first magnetoelectric conversion element and the second magnetoelectric conversion element can be arranged relative to each other with an intermediate portion as a part of the second lead frame sandwiched therebetween, and the intermediate portion allows current to flow in a second direction intersecting the first direction, the first direction being a direction from the first magnetoelectric conversion element toward the second magnetoelectric conversion element. The first magnetoelectric conversion element can be electrically connected to the signal processing IC via a plurality of first wires that do not cross the second lead frame. The second magnetoelectric conversion element can be electrically connected to the signal processing IC via a plurality of second wires that do not cross the second lead frame. The width of the signal processing IC in the direction from the second terminal portion toward the first terminal portion can be longer than the width of the signal processing IC in the direction intersecting the direction from the second terminal portion toward the first terminal portion when viewed from above.

[0031] In the current sensor, when the height from the first surface of the signal processing IC to the magnetically sensitive surfaces of the first magnetoelectric conversion element and the second magnetoelectric conversion element is set to Tb and the width in the first direction is set to Wb, 0.050mm≤Tb≤3×Wb is satisfied.

[0032] A current sensor according to one embodiment of the present invention may include a first lead frame having a first terminal portion. The current sensor may include a signal processing IC, the second surface of which is supported on the first surface of the first lead frame, and the signal processing IC is electrically connected to the first lead frame. The current sensor may include a first magnetoelectric conversion element and a second magnetoelectric conversion element, which are independently configured from the signal processing IC, are mounted on the first surface of the signal processing IC on the side opposite to the second surface, and output a signal to be processed by the signal processing IC to the signal processing IC. The current sensor may include a second lead frame, which has a second terminal portion opposite to the first terminal portion when viewed from above, at least a portion of the second lead frame is arranged opposite to the first surface of the signal processing IC, and the second lead frame partially surrounds the first magnetoelectric conversion element and the second magnetoelectric conversion element when viewed from above, and a measurement current to be measured by the first magnetoelectric conversion element and the second magnetoelectric conversion element flows through the second lead frame. The current sensor may include a plurality of first wires electrically connecting the first magnetoelectric conversion element and the signal processing IC. The current sensor may include a plurality of second wires electrically connecting the second magnetoelectric conversion element and the signal processing IC. The current sensor may include a plurality of first pads located on the signal processing IC and physically connected to the plurality of first wires, respectively. The current sensor may include a plurality of second pads located on the signal processing IC and physically connected to the plurality of second wires, respectively. When viewed from above, the first magnetoelectric conversion element and the second magnetoelectric conversion element may be arranged opposite to each other with a middle portion as a part of the second lead frame sandwiched therebetween, the middle portion causing current to flow in a second direction intersecting the first direction, the first direction being a direction from the first magnetoelectric conversion element toward the second magnetoelectric conversion element. The plurality of first pads and the plurality of second pads may not overlap with the second lead frame when viewed from above. The multiple first solder pads can be located on the first terminal part side and / or the second terminal part side relative to the first magnetoelectric conversion element when viewed from above, and the multiple second solder pads can be located on the first terminal part side and / or the second terminal part side relative to the second magnetoelectric conversion element when viewed from above.

[0033] It should be noted that the above summary of the invention does not list all the features of the present invention. In addition, subsets of these feature groups may also constitute inventions. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1AIt is a schematic plan view of the current sensor according to the first embodiment when viewed from the top surface side (Z-axis direction).

[0035] Figure 1B yes Figure 1A The current sensor 10 is shown in a cross-sectional view taken along line AA.

[0036] Figure 1C This is a diagram for explaining the positional relationship between the lead frame on the signal terminal side and the magneto-electric conversion element.

[0037] Figure 2A This is a schematic plan view of the lead frame and the magneto-electric conversion element on the current conductor side as viewed from the top surface side (Z-axis direction).

[0038] Figure 2B This is a schematic plan view of a lead frame on the current conductor side and a magneto-electric conversion element according to a modification example when viewed from the top surface side (Z-axis direction).

[0039] Figure 2C This is a schematic plan view of a lead frame on the current conductor side and a magneto-electric conversion element according to a modification example when viewed from the top surface side (Z-axis direction).

[0040] Figure 3 This is a diagram for explaining the distance between the magnetoelectric conversion element and the conductor.

[0041] Figure 4 yes Figure 1B An enlarged view of the surrounding area of ​​the magnetoelectric conversion element.

[0042] Figure 5 This is a diagram for explaining the positional relationship between the lead frame on the current conductor side and the magneto-electric conversion element.

[0043] Figure 6 This is a diagram for explaining the distance between magnetoelectric conversion elements.

[0044] Fig. 7A It is a schematic plan view of the current sensor according to the second embodiment when viewed from the top surface side (Z-axis direction).

[0045] Figure 7B yes Fig. 7A AA line cross-sectional view of the current sensor shown.

[0046] Description of symbols

[0047] 10Current sensor

[0048] 20a, 20b magnetoelectric conversion element

[0049] 22a, 22b, 108 wires

[0050] 23a, 23b pads

[0051] 100 signal processing IC

[0052] 130 Sealing part

[0053] 140 lead frame

[0054] 141 Conductor

[0055] 142 terminal part

[0056] 142a, 142b terminals

[0057] 143 Steps

[0058] 150 lead frame

[0059] 151IC suspension unit

[0060] 152 terminal part

[0061] 152a terminal

[0062] 154 Supporting part

[0063] 155 Steps

[0064] 156 imaginary line

[0065] 1411 Part 1

[0066] 1412 Part 2

[0067] 1413 Connection part

[0068] Extensions of 1414, 1414a, 1415, 1415a, 1416, and 1416a DETAILED DESCRIPTION

[0069] Hereinafter, the present invention will be described by way of the embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all combinations of features described in the embodiments are necessarily essential to the solution means of the invention.

[0070] Figure 1A and Figure 1B The internal structure of a semiconductor package that functions as the current sensor 10 according to the first embodiment is shown. Figure 1A It is a schematic plan view of the current sensor 10 according to the first embodiment when viewed from the top surface side (Z-axis direction). Figure 1B yes Figure 1A The current sensor 10 is shown in a cross-sectional view taken along line AA.

[0071] Regarding coordinates, Figure 1AIn the diagram, the direction parallel to the paper surface and from bottom to top is defined as the X-axis direction, the direction parallel to the paper surface and from right to left is defined as the Y-axis direction, and the direction perpendicular to the paper surface and from the back to the front is defined as the Z-axis direction. Any of the X-axis, Y-axis, and Z-axis is orthogonal to the other axes.

[0072] The current sensor 10 includes a signal processing IC 100 , a magnetoelectric transducer element 20 a , a magnetoelectric transducer element 20 b , a lead frame 140 on the current conductor side, a lead frame 150 on the signal terminal side, and a sealing portion 130 .

[0073] The lead frame 140 includes a conductor 141 and a terminal portion 142. The terminal portion 142 includes a pair of terminals 142a and 142b. The conductor 141 is sealed in the sealing portion 130, and partially surrounds the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b together with a portion of the terminal portion 142. A measurement current flows through the terminal portion 142 and the conductor 141. The pair of terminals 142a and 142b are physically integrated with the conductor 141, and at least a portion of the pair of terminals 142a and 142b is exposed to the outside of the sealing portion 130. The lead frame 140 is an example of a second lead frame.

[0074] The lead frame 140 does not need to be manufactured using a structure in which a plurality of conductors 141 and a plurality of terminal portions 142 are connected to each other, and may be manufactured using a structure in which a single metal member is formed.

[0075] The lead frame 150 includes an IC suspension portion 151 and a terminal portion 152. The terminal portion 152 includes a plurality of terminals 152a. The IC suspension portion 151 is sealed in the sealing portion 130 and supports the signal processing IC 100. The plurality of terminals 152a are physically integrally formed with the IC suspension portion 151, and at least a portion of the plurality of terminals 152a is exposed to the outside of the sealing portion 130. The lead frame 150 is an example of a first lead frame. The lead frame 140 and the lead frame 150 can be formed of a conductive material having copper as a main component. The X-axis is a direction along the surface of the lead frame 140 and the lead frame 150, and is a direction in which the plurality of terminals 152a are arranged. The Y-axis is a direction along the surface of the lead frame 140 and the lead frame 150, and is a direction intersecting the X-axis. The Y-axis is also a direction in which the plurality of terminals 152a and a pair of terminals 142a, 142b extend when viewed from above. The Z axis is a direction intersecting the surfaces of lead frame 140 and lead frame 150 , a direction intersecting the circuit surface of signal processing IC 100 , and a thickness direction of sealing portion 130 .

[0076] The pair of terminals 142a, 142b and the plurality of terminals 152a are arranged opposite to each other across the signal processing IC 100 in a direction (Y-axis direction) intersecting the thickness direction (Z-axis direction) of the signal processing IC 100. The pair of terminals 142a, 142b are exposed from the side surface 130a of the sealing portion 130. The plurality of terminals 152a are exposed from the side surface 130b of the sealing portion 130 opposite to the side surface 130a. Figure 1B As shown, a pair of terminals 142a, 142b and a plurality of terminals 152a may protrude outward from mutually opposite side surfaces 130a and 130b of the sealing portion 130 at different heights in the thickness direction of the sealing portion 130. The height of a surface 1521 of the plurality of terminals 152a on the same side as the surface 100a of the signal processing IC 100 at a position intersecting with the side surface 130b of the sealing portion 130 in the thickness direction (Z-axis direction) of the sealing portion 130 and the height of a surface 1421 of the pair of terminals 142a, 142b on the same side as the surface of the signal processing IC 100 opposite to the surface 100a at a position intersecting with the side surface 130a of the sealing portion 130 in the thickness direction (Z-axis direction) of the sealing portion 130 may be the same. Alternatively, the height of the surface 1521 of the plurality of terminals 152a at the position where the terminals intersect with the side surface 130b of the sealing portion 130 in the thickness direction (Z-axis direction) of the sealing portion 130 may be located below the height of the surface 1421 of the pair of terminals 142a, 142b at the position where the terminals intersect with the side surface 130a of the sealing portion 130 in the thickness direction (Z-axis direction) of the sealing portion 130.

[0077] A pair of terminals 142a, 142b protrude from the side surface 130a toward the negative side in the Y-axis direction, and are bent toward the negative side in the Z-axis direction. Multiple terminals 152a protrude from the side surface 130b toward the positive side in the Y-axis direction, and are bent toward the negative side in the Z-axis direction. A pair of terminals 142a, 142b may also protrude from the side surface 130a toward the negative side in the Y-axis direction, and be bent toward the positive side in the Z-axis direction. Multiple terminals 152a may also protrude from the side surface 130b toward the positive side in the Y-axis direction, and be bent toward the positive side in the Z-axis direction. A pair of terminals 142a, 142b and multiple terminals 152a may not be bent. That is, a pair of terminals 142a, 142b may also protrude from the side surface 130a toward the negative side in the Y-axis direction, and not be bent toward the positive and negative sides in the Z-axis direction. The plurality of terminals 152 a may protrude from the side surface 130 b toward the positive side in the Y-axis direction and may not be bent toward the positive side or the negative side in the Z-axis direction.

[0078] The IC suspension portion 151 includes a support portion 154 that supports the signal processing IC 100. The lead frame 150 may have a step portion 155, which is a portion of the support portion 154 that is recessed in a direction away from the conductor 141 (bottom surface side of the sealing portion 130) in the thickness direction (Z-axis direction). The step portion 155 is an example of a first step portion. The signal processing IC 100 may be fixed on the surface 154a of the support portion 154 via an adhesive layer. The adhesive layer may be a chip mounting film. The lead frame 140 has a step portion 143, which is a portion of the opposite portion opposite to the signal processing IC 100 that protrudes in a direction away from the signal processing IC 100 in the thickness direction. The step portion 143 is an example of a second step portion. The step portion 155 and the step portion 143 may be formed by performing a semi-through process on the lead frame 150 and the lead frame 140.

[0079] Figure 1C 1 is a diagram for explaining the positional relationship between the lead frame 150 and the magneto-electric conversion elements 20a and 20b constituting the current sensor 10 according to the first embodiment. Figure 1C As shown, the imaginary line 156 extending from the end surface of the terminal portion 142 side of the IC suspension portion 151 along the X direction can pass through the center of the magnetoelectric conversion element 20a and the center of the magnetoelectric conversion element 20b when viewed from above. Therefore, in the process of manufacturing the current sensor 10, when configuring the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b, their centers can pass through the imaginary line 156. Therefore, it is possible to improve the positional accuracy when the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b are configured above the signal processing IC 100. The imaginary line 156 can also be defined by a step, a notch, and a through hole formed in the IC suspension portion 151 instead of passing through the end surface of the IC suspension portion 151.

[0080] The step portion 143 preferably protrudes in the thickness direction relative to the terminal portion 142 by an amount greater than 0 times the thickness Ta of the lead frame 140 and not more than 0.6 times the thickness Ta. By suppressing the height of the step portion 143 to such a range, semi-through processing with high dimensional accuracy in both the height direction and the plane direction can be achieved, and as a result of a design that takes manufacturing variations into consideration, the distance between the conductor 141 and the signal processing IC 100 can be shortened.

[0081] The magnetoelectric conversion elements 20a and 20b are electrically connected to the signal processing IC 100 via a plurality of wires 22a and 22b. The magnetoelectric conversion elements 20a and 20b are independently configured from the signal processing IC 100, and output signals to be processed by the signal processing IC 100 to the signal processing IC 100. The signal processing IC 100 is electrically connected to a plurality of terminals 152a via wires 108. The wires 22a and 22b and the wires 108 can be formed of a conductive material mainly composed of Au, Ag, Cu or Al. Figure 1A As shown, the signal processing IC 100 has a plurality of pads 23a and 23b on the surface 100a, and the signal processing IC 100 is electrically connected to the magnetoelectric conversion elements 20a and 20b by connecting the plurality of pads 23a and 23b to the plurality of wires 22a and 22b. The plurality of pads 23a is an example of a plurality of first pads, and the plurality of pads 23b is an example of a plurality of second pads. The plurality of pads 23a connected to the plurality of wires 22a and the plurality of pads 23b connected to the plurality of wires 22b may not overlap with the lead frame 140 when viewed from above. The plurality of pads 23a may be located on the terminal portion 152 side and / or the terminal portion 142 side relative to the magnetoelectric conversion element 20a when viewed from above, and the plurality of pads 23b may be located on the terminal portion 152 side and / or the terminal portion 142 side relative to the magnetoelectric conversion element 20b when viewed from above.

[0082] The magnetoelectric transducers 20a and 20b may protrude from the surface 100a of the signal processing IC 100 in a side view so that the magnetically sensitive surfaces of the magnetoelectric transducers 20a and 20b overlap the conductor 141. This can improve the sensitivity of the magnetoelectric transducers 20a and 20b.

[0083] The magnetoelectric conversion elements 20a and 20b detect a magnetic field in a specific direction that changes according to the measurement current flowing through the conductor 141. The signal processing IC 100 amplifies a signal corresponding to the magnitude of the magnetic field and outputs the amplified signal via the terminal 152a. The magnetoelectric conversion elements 20a and 20b are composed of a compound semiconductor formed on a GaAs substrate and can be a chip cut out in a square or rectangular shape when viewed from above in the Z-axis direction.

[0084] The magnetoelectric conversion elements 20a and 20b can have a substrate made of silicon or a compound semiconductor and a magnetoelectric conversion unit arranged on the substrate. The thickness of the substrate is adjusted by grinding the surface on the negative side of the Z-axis direction. Since the magnetic field in the Z-axis direction is detected, for example, a horizontal Hall element is appropriate as the magnetoelectric conversion elements 20a and 20b. In addition, if the magnetoelectric conversion elements 20a and 20b are arranged at a position to detect the magnetic field in any axial direction on the XY plane, for example, if they are arranged at a position to detect the magnetic field in the X-axis direction, a magnetoresistive element or a fluxgate element is appropriate as the magnetoelectric conversion elements 20a and 20b.

[0085] The signal processing IC100 is a large-scale integrated circuit (LSI). The signal processing IC100 is a signal processing circuit composed of a Si monolithic semiconductor formed on a Si substrate. The signal processing circuit processes the output signal corresponding to the magnitude of the magnetic field output from the magnetoelectric conversion elements 20a and 20b. The signal processing circuit corrects the measured current flowing through the conductor 141 based on the output signal, and outputs the output signal representing the accurate current value through the terminal 152a. The signal processing circuit reduces the noise components contained in the output signal of the magnetoelectric conversion element 20a and the output signal of the magnetoelectric conversion element 20b based on the difference between the output signal of the magnetoelectric conversion element 20a and the output signal of the magnetoelectric conversion element 20b, amplifies the output signal of the magnetoelectric conversion element 20a and the output signal of the magnetoelectric conversion element 20b after the noise components are reduced, calculates the current value of the measured current based on the amplified output signal, and outputs the output signal representing the current value.

[0086] The width Wy of the signal processing IC 100 in the Y-axis direction is longer than the width Wx of the signal processing IC 100 in the X-axis direction. With such a structure, the wire 108 connecting the signal processing IC 100 and the plurality of terminals 152a can be separated from the conductor 141. Thus, it is possible to suppress the influence of noise accompanying the change of the current flowing through the conductor 141 on the signal outputted through the wire 108.

[0087] It should be noted that if the influence of noise associated with the change in the current flowing through the conductor 141 on the signal output through the wire 108 is within the allowable range, the width Wy of the signal processing IC 100 in the Y-axis direction may be less than the width Wx of the signal processing IC 100 in the X-axis direction.

[0088] The wiring included in the uppermost layer on the side of the surface 100a of the signal processing IC 100 is preferably arranged at a position that does not overlap with the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b in the thickness direction (Z-axis direction). Alternatively, the wiring included in the uppermost layer on the side of the surface 100a of the signal processing IC 100 is preferably arranged at a position that overlaps with the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b in the thickness direction (Z-axis direction), and has a width that overlaps with the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b in a top view. Thus, the unevenness of the portion where the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b are arranged on the surface 100a of the signal processing IC 100 can be eliminated. Thus, the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b can be reliably bonded to the surface 100a of the signal processing IC 100. This can prevent the magnetoelectric transducer elements 20 a and 20 b from peeling off from the surface 100 a of the signal processing IC 100 and adversely affecting the reliability of the bonding portion between the adjacent wires 22 a and 22 b and the signal processing IC 100 .

[0089] The sealing part 130 uses a molded resin to seal the magnetoelectric conversion elements 20a, 20b, the conductor 141, the IC suspension part 151, the portion other than the exposed portion of the terminal part 142, the portion other than the exposed portion of the terminal part 152, the signal processing IC 100, the wires 22a, 22b, and the wire 108. The lead frame 140 is electrically insulated from the magnetoelectric conversion elements 20a, 20b and the signal processing IC 100 by the sealing part 130, and there is no interface between the components. As a result, no discharge is transmitted along the interface under the use environment. The molded resin is composed of, for example, an epoxy-based thermosetting resin with silicon dioxide added, and can be formed into a semiconductor package by transfer molding.

[0090] In the first embodiment, an example in which the current sensor 10 includes two magneto-electric transducers 20 a and 20 b is described, but the current sensor 10 may include one or more magneto-electric transducers.

[0091] Figure 2A This is a schematic top view of the lead frame 140 and the magnetoelectric conversion elements 20a and 20b constituting the current sensor 10 according to the first embodiment, as viewed from the top surface side (Z-axis direction). The lead frame 140 has a first portion 1411, a second portion 1412, a connecting portion 1413, and an extended portion 1414. The second portion 1412 is an example of an intermediate portion. The extended portion 1414 is an example of a first extended portion.

[0092] The first portion 1411 extends from the terminal 142a along the Y-axis direction toward the terminal portion 152 side (the positive direction of the Y-axis). The second portion 1412 extends from the terminal 142b along the Y-axis direction toward the terminal portion 152 side (the positive direction of the Y-axis). The connecting portion 1413 extends from the first portion 1411 along the X-axis direction intersecting the Y-axis direction and is connected to the second portion 1412. The lead frame 140 further includes an extension portion 1414a extending from the extension portion 1414 toward the terminal 142b side and separated from the terminal 142b. The extension portion 1414a is an example of a second extension portion. The direction intersecting the Y-axis direction may be a direction orthogonal to the Y-axis direction, that is, a direction forming a 90-degree angle with respect to the Y-axis direction. The direction intersecting the Y-axis direction may be a direction forming an angle of 80 to 100 degrees with respect to the Y-axis direction or a direction forming an angle of 85 to 95 degrees with respect to the Y-axis direction.

[0093] The three side surfaces of the magnetoelectric transducer 20a are surrounded by the first portion 1411, the connecting portion 1413, and the second portion 1412 when viewed from above. The three side surfaces of the magnetoelectric transducer 20b are surrounded by the terminal 142b, the second portion 1412, and the extension portion 1414. The magnetoelectric transducer 20a and the magnetoelectric transducer 20b are arranged opposite to each other with the second portion 1412 interposed therebetween when viewed from above.

[0094] The shape of the lead frame 140 surrounding the three side surfaces of the magnetoelectric conversion elements 20a and 20b is not limited to Figure 2A Shape shown.

[0095] Figure 2B This is a schematic plan view of a lead frame 140 and magneto-electric conversion elements 20 a and 20 b according to another example of the current sensor 10 according to the first embodiment, as viewed from the top surface side (Z-axis direction).

[0096] The lead frame 140 includes a first portion 1411, a second portion 1412, a connecting portion 1413, and an extension portion 1415. The first portion 1411 extends from the terminal 142a along the Y-axis direction to the terminal portion 152 side (the positive direction of the Y-axis). The second portion 1412 extends from the terminal 142b along the Y-axis direction to the terminal portion 152 side (the positive direction of the Y-axis). The connecting portion 1413 extends from the first portion 1411 along the X-axis direction intersecting the Y-axis direction and is connected to the second portion 1412. The lead frame 140 also includes an extension portion 1415 extending from the terminal 142b along the Y-axis direction and surrounding the magnetoelectric conversion element 20b together with the terminal 142b and the second portion 1412. The second portion 1412 is an example of an intermediate portion. The extension portion 1415 is an example of a first extension portion. The lead frame 140 may further include an extension portion 1415 a extending from an end of the extension portion 1415 toward the connection portion 1413 and spaced apart from the connection portion 1413 .

[0097] No matter Figure 2A and Figure 2B In any lead frame 140, the width W2 of the second portion 1412 in the X-axis direction is less than the width W1 of the first portion 1411 in the X-axis direction. Thus, the magnetoelectric conversion elements 20a and 20b can detect changes in the magnetic field caused by the current passing through the second portion 1412 with a relatively narrow width. That is, the magnetoelectric conversion elements 20a and 20b can detect changes in the magnetic field caused by a relatively high current density, thereby improving the S / N of the current sensor 10.

[0098] Moreover, the width W3 of the connecting portion 1413 in the Y-axis direction is less than the width W1 of the first portion 1411 in the X-axis direction. Thus, the overlapping area in the thickness direction of the lead frame 140 and the signal processing IC 100 can be reduced. Thus, the signal processing IC 100 can be less susceptible to the noise caused by the voltage change ΔV / Δt when the current flows to the lead frame 140. In addition, the width W3 of the connecting portion 1413 in the Y-axis direction can be greater than the width W2 of the second portion 1412 in the X-axis direction. Thus, the current flowing through the second portion 1412 is concentrated, and in the magnetoelectric conversion elements 20a and 20b, the change in the magnetic field caused by the relatively high current density can be detected, so the S / N of the current sensor 10 can be improved.

[0099] Figure 2C This is a schematic plan view of a lead frame 140 and magneto-electric conversion elements 20 a and 20 b according to another example of the current sensor 10 according to the first embodiment, as viewed from the top surface side (Z-axis direction).

[0100] The lead frame 140 includes a first portion 1411, a second portion 1412, a connecting portion 1413, and an extension portion 1416. The first portion 1411 extends from the terminal 142a along the Y-axis direction to the terminal portion 152 side (the positive direction of the Y-axis). The second portion 1412 extends from the terminal 142b along the Y-axis direction to the terminal portion 152 side (the positive direction of the Y-axis). The connecting portion 1413 extends from the first portion 1411 along the X-axis direction intersecting the Y-axis direction and is connected to the second portion 1412. That is, the connecting portion 1413 connects the first portion 1411 and the second portion 1412. The lead frame 140 also includes an extension portion 1416 that extends from the terminal 142a and the terminal 142b along the Y-axis direction and surrounds the magnetoelectric conversion element 20b together with the connecting portion 1413. The connecting portion 1413 is an example of an intermediate portion. The extension portion 1416 is an example of a first extension portion. The lead frame 140 may further include an extension portion 1416a extending from an end portion of the extension portion 1416 toward the other extension portion 1416 and separated from the other extension portion 1416. The extension portion 1416a is an example of a second extension portion.

[0101] exist Figure 2C In the embodiment, the width W1 of the first portion 1411 in the X-axis direction and the width W2 of the second portion 1412 in the X-axis direction may have any size relationship. By increasing the width W1 of the first portion 1411 in the X-axis direction and the width W2 of the second portion 1412 in the X-axis direction to the same extent as the terminals 142a and 142b, the cross-sectional area of ​​the heat dissipation path can be ensured to be large while reducing the resistance value of the lead frame 140, so that a large current can flow.

[0102] exist Figure 2C , the width W3 of the connecting portion 1413 in the Y-axis direction is less than the widths W1 and W2 of the first portion 1411 and the second portion 1412 in the X-axis direction. By doing so, the magnetoelectric conversion elements 20a and 20b can each detect a change in the magnetic field caused by the current passing through the relatively narrow connecting portion 1413. That is, the magnetoelectric conversion elements 20a and 20b can each detect a change in the magnetic field caused by a relatively high current density, thereby improving the S / N of the current sensor 10.

[0103] Through Figure 2A , Figure 2B , Figure 2C By enclosing the magnetoelectric conversion element 20b with the lead frame 140 in the same manner as the magnetoelectric conversion element 20a, the coupling capacitance between the wire 22b and the lead frame 140 can be made close to the coupling capacitance between the wire 22a and the lead frame 140. This can reduce the influence of noise caused by the voltage change ΔV / Δt when current flows to the lead frame 140.

[0104] The plurality of wires 22a are electrically connected to the signal processing IC 100 in a manner that they extend in directions different from the magnetoelectric converter element 20b side when viewed from above and do not cross the lead frame 140. The plurality of wires 22a can be electrically connected to the signal processing IC 100 in a manner that they extend in directions different from the direction from the magnetoelectric converter element 20a toward the magnetoelectric converter element 20b in four directions when viewed from above and do not cross the lead frame 140. The plurality of wires 22a can be electrically connected to the signal processing IC 100 in a manner that they extend in directions different from the direction from the magnetoelectric converter element 20a toward the magnetoelectric converter element 20b in four directions when viewed from above. For example, the plurality of wires 22a are electrically connected to the signal processing IC 100 in a manner that they extend in directions different from the straight line connecting the magnetoelectric converter element 20a and the magnetoelectric converter element 20b in a direction different from the straight line connecting the magnetoelectric converter element 20a and the magnetoelectric converter element 20b in a direction different from the straight line connecting the magnetoelectric converter element 20a and the magnetoelectric converter element 20b and do not cross the conductor 141 of the lead frame 140. Figure 2A and Figure 2B The plurality of conductive wires 22 a shown may extend along a direction in which current flows through the second portion 1412 , ie, the Y-axis direction, when viewed from above. Figure 2C The plurality of wires 22a shown can extend along the direction in which the current flows through the connecting portion 1413, i.e., the X-axis direction, when viewed from above. By configuring in this way, the magnetically sensitive surface of the magnetoelectric conversion element 20a can be brought close to the second portion 1412 or the connecting portion 1413. This can improve the sensitivity of the magnetic sensor and effectively improve the S / N ratio.

[0105] The plurality of wires 22b are electrically connected to the signal processing IC 100 in a manner that they extend in a direction different from the magnetoelectric conversion element 20a side when viewed from above and do not cross the lead frame 140. The plurality of wires 22b can be electrically connected to the signal processing IC 100 in a manner that they extend in a direction different from the direction from the magnetoelectric conversion element 20b toward the magnetoelectric conversion element 20a in four directions when viewed from above and do not cross the lead frame 140. The plurality of wires 22b can be electrically connected to the signal processing IC 100 in a manner that they extend in a direction different from the direction from the magnetoelectric conversion element 20b toward the magnetoelectric conversion element 20a in four directions when viewed from above. For example, the plurality of wires 22b are electrically connected to the signal processing IC 100 in a manner that they extend in a direction different from the straight line connecting the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b in a direction different from the straight line connecting the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b and do not cross the conductor 141 of the lead frame 140. Figure 2A and Figure 2B The plurality of conductive wires 22 b shown may extend along a direction in which current flows through the second portion 1412 , ie, the Y-axis direction, when viewed from above. Figure 2C The plurality of wires 22b shown can extend along the direction in which the current flows through the connecting portion 1413, i.e., the X-axis direction, when viewed from above. By configuring in this way, the magnetically sensitive surface of the magnetoelectric conversion element 20b can be brought close to the second portion 1412 or the connecting portion 1413. This can improve the sensitivity of the magnetic sensor and effectively improve the S / N ratio.

[0106] When the portion sandwiched by the magnetoelectric conversion elements 20a and 20b in the second portion 1412 or the connecting portion 1413 is set as the middle portion, the distance between each magnetoelectric conversion element 20a and 20b and the middle portion can be shortened by extending the plurality of wires 22a and 22b in directions not facing the magnetoelectric conversion elements 20a and 20b in a plan view. Figure 3 As shown, the distance k1 between the magnetoelectric transducer 20a and the middle portion is shorter than the distance k2 between the magnetoelectric transducer 20a and the conductor 141 in the direction in which the wire 22a extends. In addition, the distance k3 between the magnetoelectric transducer 20b and the middle portion is shorter than the distance k4 between the magnetoelectric transducer 20b and the lead frame 140 in the direction in which the wire 22b extends.

[0107] exist Figure 2A , Figure 2B , Figure 2C In FIG. 1 , the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b are rectangular in a plan view. Figure 2A and Figure 2B In the embodiment, the second portion 1412 is a rectangle. Figure 2C In the embodiment, the connecting portion 1413 is rectangular. Figure 2A and Figure 2B In the top view, there are no wires or components in the areas between the side surfaces of the magnetoelectric transducer 20a and the magnetoelectric transducer 20b that are opposite to the second portion 1412 and the side surfaces of the second portion 1412 that are opposite to the magnetoelectric transducer 20a and the magnetoelectric transducer 20b. Figure 2C In the top view, there are no wires or elements in the areas between the side surfaces of the magnetoelectric conversion elements 20a and 20b that are opposite to the connecting portion 1413 and the side surfaces of the connecting portion 1413 that are opposite to the magnetoelectric conversion elements 20a and 20b, respectively. By forming such a structure, the magnetically sensitive surfaces of the magnetoelectric conversion elements 20a and 20b can be brought close to the second portion 1412 or the connecting portion 1413.

[0108] Thus, the magnetoelectric transducers 20a and 20b can each easily detect a change in the magnetic field caused by the current flowing through the intermediate portion, and the sensitivity of the magnetoelectric transducers 20a and 20b can be efficiently improved.

[0109] It should be noted that if the sensitivity of the magnetoelectric conversion elements 20a and 20b meets the required sensitivity, the distance k1 between the magnetoelectric conversion element 20a and the middle part may be longer than the distance k2 between the magnetoelectric conversion element 20a and the conductor 141 in the direction in which the wire extends. In addition, the distance k3 between the magnetoelectric conversion element 20 and the middle part may be longer than the distance k4 between the magnetoelectric conversion element 20b and the lead frame 140 in the direction in which the wire extends.

[0110] In addition, the plurality of wires 22a and 22b are electrically connected to the signal processing IC 100 in a manner that does not cross the lead frame 140. That is, the plurality of wires 22a and 22b are electrically connected to the signal processing IC 100 without crossing the lead frame 140. Thus, the length of each of the plurality of wires 22a and 22b can be shortened. Thus, the risk of the plurality of wires 22a and 22b contacting each other can be reduced. In addition, the situation in which the induced electromotive force generated in the plurality of wires 22a and 22b by the current flowing through the lead frame 140 and the noise generated in the output of the magnetoelectric conversion elements 20a and 20b can be suppressed.

[0111] It should be noted that, if the sensitivity required for the magnetoelectric transducer elements 20a and 20b satisfies the required sensitivity, the plurality of conductive wires 22a and 22b may be extended in the directions toward the magnetoelectric transducer elements 20b and 20a, respectively.

[0112] Here, if Figure 4 As shown, if the height Tb from the surface 100a of the signal processing IC 100 to the magnetically sensitive surface 21a, 21b of the magnetoelectric conversion element 20a, 20b is not less than 3 times the width Wb of the magnetoelectric conversion element 20a, 20b, the magnetoelectric conversion element 20a, 20b cannot be stably chip-bonded on the signal processing IC 100. In addition, when the magnetoelectric conversion element is a compound semiconductor, it is easy to break when it is thin. Therefore, it is appropriate for Tb to be 0.050mm or more. That is, it is preferred to satisfy 0.050mm <Tb≤3×Wb。

[0113] In addition, in order to improve the sensitivity of the magnetoelectric conversion elements 20a and 20b, Figure 5 As shown, when viewed from the side, the magnetically sensitive surfaces 21a and 21b of the magnetoelectric conversion elements 20a and 20b are preferably arranged at a position 0.5×Ta, half of the thickness Ta of the conductor 141, away from the surface 141b of the conductor 141 facing the signal processing IC 100, closer to the center in the thickness direction of the conductor 141. Therefore, when the distance between the surface 141b of the conductor 141 and the surface 100a of the signal processing IC 100 is set to H, H preferably satisfies H≤Tb+0.5×Ta, that is, H≤3×Wb+0.5×Ta.

[0114] On the other hand, when viewed from above, in order to improve the sensitivity of the magnetoelectric conversion elements 20a and 20b, the distance between the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b needs to ensure that the conductor 141 is located at the distance between the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b. In addition, by making the width of the conductor 141 larger than 0.5 times the thickness Ta of the conductor 141, stable-shaped processing can be achieved. Therefore, as Figure 6 shown, when the distance between the center of the magnetoelectric conversion element 20a and the center of the magnetoelectric conversion element 20b is set to L, it is preferably satisfied that 0.5×Ta + Wb < L. Thereby, a conductor 141 with stable dimensions can be arranged between the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b, and the sensitivity of the magnetoelectric conversion elements 20a and 20b can be improved.

[0115] Considering the above, it is preferably satisfied that 1 / 6×Ta + 1 / 3×H < L, that is, H < 3×L - 0.5×Ta. Here, H is an important distance for ensuring withstand voltage even when a high voltage is applied between the conductor 141 and the signal processing IC 100. Considering the intersection of step errors, H needs to be at least 0.01 mm or more, so it is preferably satisfied that 0.01 mm < H < 3×L - 0.5×Ta.

[0116] Fig. 7A and Figure 7B shows the internal structure of the semiconductor package in which the current sensor 10 according to the second embodiment functions. Fig. 7A is a schematic plan view when the current sensor 10 according to the second embodiment is viewed from the top surface side (Z-axis direction). Figure 7B is Fig. 7A a cross-sectional view taken along line A-A of the current sensor 10 shown.

[0117] The current sensor 10 according to the second embodiment is different from the current sensor 10 according to the first embodiment in that the step portion 155 is not provided on the support portion 154. In the case where the conductor 140 has a large plate thickness and the step portion 143 based on the semi-through processing can be formed large or a large step can be formed by bending processing, the distance between the signal processing IC 100 and the conductor 141 can be ensured even if the step portion 155 is not provided. The other structures of the current sensor 10 according to the second embodiment can be the same as the structure of the current sensor 10 according to the first embodiment. Therefore, the current sensor 10 according to the second embodiment has the same advantages as the current sensor 10 according to the first embodiment. In the primary conductor of the shape as in Patent Document 1, the current is divided into two paths and flows in the same direction, so sometimes it is impossible to effectively increase the magnetic field passing through the magnetic sensor. Therefore, sometimes it is impossible to improve the sensitivity of the magnetic sensor and the S / N ratio. On the other hand, according to the above-mentioned current sensor 10, the sensitivity of the current sensor 10 can be improved and the S / N ratio can be effectively improved.

[0118] The present invention has been described above using the embodiments, but the technical scope of the present invention is not limited to the scope described in the above embodiments. It is obvious to those skilled in the art that various changes or improvements can be made to the above embodiments. It is obvious from the description of the claims that the modes after such changes or improvements are also included in the technical scope of the present invention.

[0119] It should be noted that the execution order of each process such as actions, processes, steps and stages in the device, system, program and method shown in the claims, specifications and drawings can be implemented in any order as long as it is not specifically stated as "before", "prior to", etc. and the output of the previous process is not used in the subsequent process. Even if the action flow in the claims, specifications and drawings is described using "first", "next", etc. for convenience, it does not mean that it must be implemented in this order.

Claims

1. A current sensor comprising: a first lead frame having a first terminal portion; a signal processing IC, wherein a second surface of the signal processing IC is supported on a first surface of the first lead frame, and the signal processing IC is electrically connected to the first lead frame; The first magnetoelectric conversion element and the second magnetoelectric conversion element are independently formed from the signal processing IC, mounted on a first surface of the signal processing IC on the opposite side to the second surface, and output a signal to be processed by the signal processing IC to the signal processing IC; a second lead frame having a second terminal portion opposite to the first terminal portion when viewed from above, at least a portion of the second lead frame being arranged opposite to the first surface of the signal processing IC, the second lead frame partially surrounding the first magnetoelectric conversion element and the second magnetoelectric conversion element when viewed from above, and through which a measurement current to be measured by the first magnetoelectric conversion element and the second magnetoelectric conversion element flows, When viewed from above, the first magnetoelectric transducer and the second magnetoelectric transducer are arranged opposite to each other with a middle portion as a part of the second lead frame sandwiched therebetween, and the middle portion allows current to flow in a second direction intersecting with a first direction, wherein the first direction is a direction from the first magnetoelectric transducer toward the second magnetoelectric transducer, The first magnetoelectric conversion element is electrically connected to the signal processing IC via a plurality of first wires, and the plurality of first wires are electrically connected to the signal processing IC in a manner that they extend in a direction different from the second magnetoelectric conversion element side when viewed from above and do not cross the second lead frame. The second magnetoelectric conversion element is electrically connected to the signal processing IC via a plurality of second wires, and the plurality of second wires are electrically connected to the signal processing IC in a manner that they extend in a direction different from the first magnetoelectric conversion element side when viewed from above and do not cross the second lead frame.

2. The current sensor according to claim 1, wherein: The second terminal portion has a pair of terminals, The second lead frame has: a first portion extending from one of the pair of terminals toward the first terminal portion; a second portion extending from the other terminal of the pair of terminals toward the first terminal portion; and a connecting portion connecting an end portion of the second portion to an end portion of the first portion, The first magnetoelectric conversion element is surrounded by the first portion, the connecting portion, and the second portion in a plan view. The intermediate portion is the second portion or the connecting portion, The distance between the first magnetoelectric transducer and the intermediate portion is shorter than the distance between the first magnetoelectric transducer and the second lead frame in the second direction. A distance between the second magneto-electric transducer element and the intermediate portion is shorter than a distance between the second magneto-electric transducer element and the second lead frame in the second direction.

3. The current sensor according to claim 2, wherein: The second lead frame further comprises: a first extension portion, in the case where the second portion is the middle portion, only one side of the first extension portion is joined to the connecting portion or the other terminal of the pair of terminals, in the case where the connecting portion is the middle portion, only one side of the first extension portion is joined to the first portion, the first extension portion being adjacent to the second magnetoelectric conversion element; and A second extension portion, only one side of which is joined to the first extension portion, the second extension portion is not joined to other portions of the second lead frame, and is adjacent to the second magneto-electric conversion element.

4. The current sensor according to claim 2, wherein: The width of the intermediate portion in the first direction is equal to or smaller than the width of the first portion in a direction intersecting the direction in which the measurement current flows.

5. The current sensor according to claim 2, wherein: In a case where the intermediate portion is the second portion, the first direction is a direction intersecting a direction connecting the second terminal portion and the first terminal portion.

6. The current sensor according to claim 5, wherein: The width of the connecting portion in the second direction is less than or equal to the width of the first portion in the first direction.

7. The current sensor according to claim 1, wherein: A width of the signal processing IC in a direction from the second terminal portion toward the first terminal portion is longer than a width of the signal processing IC in a direction intersecting the direction from the second terminal portion toward the first terminal portion in a plan view.

8. The current sensor according to claim 1, wherein: The first lead frame has an end surface on an imaginary line passing through the centers of the first magneto-electric transducer element and the second magneto-electric transducer element in a plan view.

9. The current sensor according to claim 1, wherein: When the distance between the center of the first magnetoelectric transducer and the center of the second magnetoelectric transducer is L and the thickness of the second lead frame is Ta, the distance H in the thickness direction between the signal processing IC and the second lead frame satisfies 0.01 mm. <H<3×L-0.5×Ta。 10. The current sensor according to claim 9, wherein: When the width of the first magnetoelectric transducer and the second magnetoelectric transducer in the first direction is Wb, 0.5×Ta+Wb is satisfied. <L。 11. The current sensor according to claim 9, wherein: When the height from the first surface of the signal processing IC to the magnetically sensitive surfaces of the first magnetoelectric transducer element and the second magnetoelectric transducer element is Tb and the width in the first direction is Wb, Tb≤3×Wb is satisfied.

12. The current sensor according to claim 11, wherein: Satisfies H≤3×Wb+0.5×Ta.

13. The current sensor according to claim 1, wherein: The first lead frame has a first step portion which is a portion where a support portion supporting the signal processing IC is recessed in a direction away from the second lead frame in a thickness direction.

14. The current sensor according to claim 1, wherein: The second lead frame has a second step portion which is a portion that faces the signal processing IC and protrudes in a direction away from the signal processing IC in the thickness direction.

15. The current sensor according to claim 14, wherein: The second step portion protrudes in the thickness direction relative to the second terminal portion by an amount greater than 0 times and not more than 0.6 times the thickness of the second lead frame.

16. The current sensor according to claim 1, wherein: The wiring included in the uppermost layer on the first surface side of the signal processing IC is arranged at a position that does not overlap with the first magnetoelectric transducer element and the second magnetoelectric transducer element in the thickness direction, or, The wiring included in the uppermost layer on the first surface side of the signal processing IC is arranged at a position overlapping with the first magnetoelectric transducer element and the second magnetoelectric transducer element in the thickness direction, and has a width overlapping with the first magnetoelectric transducer element and the second magnetoelectric transducer element in a plan view.

17. The current sensor according to claim 1, wherein: The current sensor also has a sealing portion, which uses a molded resin to seal the portion of the first lead frame other than the exposed portion of the first terminal portion, the portion of the second lead frame other than the exposed portion of the second terminal portion, the signal processing IC, the first magnetoelectric conversion element, and the second magnetoelectric conversion element in a state in which the second lead frame is separated from the first lead frame, the signal processing IC, the first magnetoelectric conversion element, and the second magnetoelectric conversion element.

18. The current sensor according to claim 17, wherein: The first height is the same as the second height, or the first height is lower than the second height, the first height is the height of the surface of the first terminal part at the position where the first side intersects with the first side, on the same side as the first side of the signal processing IC, in the thickness direction of the sealing part, the first side is the surface of the sealing part where the first terminal part is exposed, and the second height is the height of the surface of the second terminal part at the position where the second side intersects with the second side, on the same side as the second side of the signal processing IC, in the thickness direction of the sealing part, and the second side is the surface of the sealing part where the second terminal part is exposed.

19. The current sensor according to claim 1, wherein: The first magnetoelectric conversion element, the second magnetoelectric conversion element and the middle portion are rectangular in a plan view. When viewed from above, there are no wires or elements in the areas between the side surfaces of the first magnetoelectric transducer element and the second magnetoelectric transducer element opposite to the middle portion and the side surfaces of the middle portion opposite to the first magnetoelectric transducer element and the second magnetoelectric transducer element respectively.

20. A current sensor comprising: a first lead frame having a first terminal portion; a signal processing IC, wherein a second surface of the signal processing IC is supported on a first surface of the first lead frame, and the signal processing IC is electrically connected to the first lead frame; The first magnetoelectric conversion element and the second magnetoelectric conversion element are independently formed from the signal processing IC, mounted on a first surface of the signal processing IC on the opposite side to the second surface, and output a signal to be processed by the signal processing IC to the signal processing IC; and a second lead frame having a second terminal portion opposite to the first terminal portion when viewed from above, at least a portion of the second lead frame being arranged opposite to the first surface of the signal processing IC, the second lead frame partially surrounding the first magnetoelectric conversion element and the second magnetoelectric conversion element when viewed from above, and through which a measurement current to be measured by the first magnetoelectric conversion element and the second magnetoelectric conversion element flows, When viewed from above, the first magnetoelectric transducer and the second magnetoelectric transducer are arranged opposite to each other with a middle portion as a part of the second lead frame sandwiched therebetween, and the middle portion allows current to flow in a second direction intersecting with a first direction, wherein the first direction is a direction from the first magnetoelectric transducer toward the second magnetoelectric transducer, The first magnetoelectric conversion element is electrically connected to the signal processing IC via a plurality of first conductive wires that do not cross the second lead frame. The second magnetoelectric conversion element is electrically connected to the signal processing IC via a plurality of second wires that do not cross the second lead frame. The second terminal portion has a pair of terminals, The second lead frame has: a first portion extending from one of the pair of terminals toward the first terminal portion; a second portion extending from the other terminal of the pair of terminals toward the first terminal portion; and a connecting portion connecting an end portion of the second portion to an end portion of the first portion, The first magnetoelectric conversion element is surrounded by the first portion, the connecting portion, and the second portion in a plan view. The intermediate portion is the second portion or the connecting portion, The distance between the first magnetoelectric transducer and the intermediate portion is shorter than the distance between the first magnetoelectric transducer and the second lead frame in the second direction. A distance between the second magneto-electric transducer element and the intermediate portion is shorter than a distance between the second magneto-electric transducer element and the second lead frame in the second direction.

21. The current sensor according to claim 20, wherein: When the middle portion is the second portion, the width of the middle portion in the first direction is less than the width of the connecting portion in the second direction. When the intermediate portion is the connecting portion, a width of the intermediate portion in the first direction is less than or equal to a width of the second portion in the second direction.

22. A current sensor comprising: a first lead frame having a first terminal portion; a signal processing IC, wherein a second surface of the signal processing IC is supported on a first surface of the first lead frame, and the signal processing IC is electrically connected to the first lead frame; A first magnetoelectric conversion element and a second magnetoelectric conversion element are independently formed from the signal processing IC, are mounted on a first surface of the signal processing IC on the opposite side to the second surface, and output a signal to be processed by the signal processing IC to the signal processing IC; and a second lead frame having a second terminal portion opposite to the first terminal portion when viewed from above, at least a portion of the second lead frame being arranged opposite to the first surface of the signal processing IC, the second lead frame partially surrounding the first magnetoelectric conversion element and the second magnetoelectric conversion element when viewed from above, and through which a measurement current to be measured by the first magnetoelectric conversion element and the second magnetoelectric conversion element flows, When viewed from above, the first magnetoelectric transducer and the second magnetoelectric transducer are arranged opposite to each other with a middle portion as a part of the second lead frame sandwiched therebetween, and the middle portion allows current to flow in a second direction intersecting with a first direction, wherein the first direction is a direction from the first magnetoelectric transducer toward the second magnetoelectric transducer, The first magnetoelectric conversion element is electrically connected to the signal processing IC via a plurality of first conductive wires that do not cross the second lead frame. The second magnetoelectric conversion element is electrically connected to the signal processing IC via a plurality of second wires that do not cross the second lead frame. A width of the signal processing IC in a direction from the second terminal portion toward the first terminal portion is longer than a width of the signal processing IC in a direction intersecting the direction from the second terminal portion toward the first terminal portion in a plan view.

23. The current sensor according to claim 22, wherein: When a height from the first surface of the signal processing IC to the magnetically sensitive surfaces of the first magnetoelectric transducer element and the second magnetoelectric transducer element is Tb and a width in the first direction is Wb, 0.050 mm ≤ Tb ≤ 3×Wb is satisfied.

24. A current sensor comprising: a first lead frame having a first terminal portion; a signal processing IC, wherein a second surface of the signal processing IC is supported on a first surface of the first lead frame, and the signal processing IC is electrically connected to the first lead frame; The first magnetoelectric conversion element and the second magnetoelectric conversion element are independently formed from the signal processing IC, mounted on a first surface of the signal processing IC on the opposite side to the second surface, and output a signal to be processed by the signal processing IC to the signal processing IC; a second lead frame having a second terminal portion opposite to the first terminal portion in a plan view, at least a portion of the second lead frame being arranged opposite to the first surface of the signal processing IC, the second lead frame partially surrounding the first magnetoelectric conversion element and the second magnetoelectric conversion element in a plan view, and through which a measurement current to be measured by the first magnetoelectric conversion element and the second magnetoelectric conversion element flows; A plurality of first wires electrically connecting the first magnetoelectric conversion element and the signal processing IC; A plurality of second wires electrically connecting the second magnetoelectric conversion element and the signal processing IC; a plurality of first pads, located on the signal processing IC and physically connected to the plurality of first wires respectively; and A plurality of second pads are located on the signal processing IC and are physically connected to the plurality of second wires respectively. When viewed from above, the first magnetoelectric transducer and the second magnetoelectric transducer are arranged opposite to each other with a middle portion as a part of the second lead frame sandwiched therebetween, and the middle portion allows current to flow in a second direction intersecting with a first direction, wherein the first direction is a direction from the first magnetoelectric transducer toward the second magnetoelectric transducer, The plurality of first pads and the plurality of second pads do not overlap with the second lead frame when viewed from above. The multiple first solder pads are located on the first terminal part side and / or the second terminal part side relative to the first magnetoelectric conversion element when viewed from above, and the multiple second solder pads are located on the first terminal part side and / or the second terminal part side relative to the second magnetoelectric conversion element when viewed from above.

Images