Current sensor

Abstract

The invention provides a current sensor. This current sensor is provided with: a first lead frame that includes a first terminal part and a conductor part connected to the first terminal part, and through which a measurement current measured by at least one magnetoelectric conversion element flows; and a signal processing IC that is disposed on a second surface side of the conductor section opposite to the first surface, has a circuit surface on which the at least one magnetoelectric conversion element is disposed, and processes a signal output from the at least one magnetoelectric conversion element. The conductor portion has: a first corner portion located between a first end surface on the opposite side from the side connected to the first terminal portion and a second surface facing the signal processing IC; and a second corner section located between the first end surface and the first surface on the opposite side of the second surface facing the signal processing IC. An area of an outer surface of the first corner portion is larger than an area of an outer surface of the second corner portion.

Description

Technical Field

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

[0002] Patent Document 1 discloses a current sensor including a conductive wire that connects a magnetic sensor and a signal processing IC without crossing a primary conductor.

[0003] [Prior art literature]

[0004] [Patent Document]

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

[0006] A current sensor according to one embodiment of the present invention may include at least one magnetoelectric conversion element. The current sensor includes a first lead frame, the first lead frame includes a first terminal portion and a conductor portion connected to the first terminal portion, and the measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion. The current sensor includes a signal processing IC, the signal processing IC is arranged on the second surface side opposite to the first surface of the conductor portion, has a circuit surface on which the at least one magnetoelectric conversion element is arranged and opposite to the second surface, and processes the signal output from the at least one magnetoelectric conversion element. The current sensor includes a sealing portion, the sealing portion sealing the at least one magnetoelectric conversion element, the conductor portion and the signal processing IC. The conductor portion has a first corner and a second corner, the first corner is located between a first end surface on the opposite side of the side connected to the first terminal portion and a second surface opposite to the signal processing IC, and the second corner is located between the first end surface and a first surface on the opposite side of the second surface opposite to the signal processing IC. The area of ​​the outer surface of the first corner is larger than the area of ​​the outer surface of the second corner.

[0007] In the current sensor, the first corner portion may be a chamfered surface.

[0008] In any of the current sensors, either a width in a direction along the second surface of the conductor portion when the first corner is projected in a direction along the first end surface, or a width in a direction along the first end surface when the first corner is projected in a direction along the second surface of the conductor portion may be larger than 15 μm and shorter than the thickness of the conductor portion.

[0009] In any of the current sensors, the width of the first corner in the direction along the second surface of the conductor portion when projected in the direction along the first end surface may be longer than the width of the first corner in the direction along the second surface of the conductor portion when projected in the direction along the second surface of the conductor portion.

[0010] In any of the current sensors, the conductor portion may include: a first portion connected to the first terminal portion; and a second portion arranged opposite to the circuit surface of the signal processing IC, and connected to the first portion by being offset relative to the first portion in a direction away from the circuit surface of the signal processing IC in a thickness direction. The second portion has a third corner portion, and the third corner portion is located between a second end surface on a side connected to the first portion and a first surface on the opposite side of the second surface opposite to the circuit surface of the signal processing IC. The area of ​​the outer surface of the third corner portion is larger than the area of ​​the outer surface of the fourth corner portion, and the fourth corner portion is located between the second end surface of the second portion and the first surface of the first portion on the same side as the first surface of the second portion.

[0011] In any of the current sensors, the third corner may be a chamfered surface.

[0012] In any of the current sensors, either a width in a direction along a first surface opposite to the second surface of the conductor portion when the third corner is projected in a direction along the second end surface, or a width in a direction along the second end surface when the third corner is projected in a direction along the first surface of the conductor portion may be greater than 15 μm and shorter than the thickness of the conductor portion.

[0013] In any of the above current sensors, an offset amount of the second portion relative to the first portion may be equal to or smaller than 0.6 times the thickness of the conductor portion.

[0014] In any of the current sensors, the second end surface of the second portion may have a shear surface.

[0015] In any of the current sensors, the current sensor may further include a second lead frame, the second lead frame includes a second terminal portion and a support portion, and is electrically insulated from the first lead frame, the second terminal portion is arranged opposite to the first terminal portion across the signal processing IC when viewed from above and is electrically connected to the signal processing IC, and the support portion uses a first surface to support the surface of the signal processing IC on the opposite side of the circuit surface on the conductor side. The first portion has a fifth corner portion, and the fifth corner portion is located between a third end surface on one side connecting the second portion and a second surface on the same side as the second surface of the second portion. The area of ​​the outer surface of the fifth corner portion is larger than the area of ​​the outer surface of the sixth corner portion, and the sixth corner portion is located between the third end surface of the first portion and the second surface of the second portion.

[0016] In any of the above current sensors, the fifth corner may be a chamfered surface.

[0017] In any of the current sensors, either a width of the fifth corner in a direction along the second surface of the first portion when projected in a direction along the third end surface, or a width of the fifth corner in a direction along the third end surface when projected in a direction along the second surface of the first portion may be greater than 15 μm and shorter than the thickness of the conductor portion.

[0018] In any of the current sensors, the support portion may include a seventh corner and an eighth corner, the seventh corner being located between the first surface supporting the signal processing IC and the fourth end surface on the first terminal portion side, and the eighth corner being located between the second surface on the opposite side of the first surface supporting the signal processing IC and the fourth end surface. The area of ​​the outer surface of the seventh corner is larger than the area of ​​the outer surface of the eighth corner.

[0019] In any of the above current sensors, the sealing portion may be formed of a mold resin, the mold resin may contain a filler having a diameter of 20 μm or more, and a filling rate of the filler may be 60% or more.

[0020] In any of the current sensors, the at least one magneto-electric transducer may protrude from the circuit surface to a position overlapping with the conductor portion when viewed from a direction intersecting a thickness direction of the at least one magneto-electric transducer.

[0021] In any of the above current sensors, the at least one magneto-electric conversion element may be formed of a chip different from a chip forming the signal processing IC.

[0022] In any of the current sensors, the at least one magneto-electric conversion element may be built in a chip constituting the signal processing IC.

[0023] In any of the current sensors, the conductor portion may include at least one slit portion, and the at least one magneto-electric conversion element may be disposed in the at least one slit portion in a plan view so as to be at least partially surrounded by the conductor portion.

[0024] In any of the current sensors, the at least one magneto-electric conversion element may be fixed to the circuit surface by chip bonding in the at least one slit portion when viewed from above, and may be electrically connected to the signal processing IC by wire bonding.

[0025] In any of the current sensors, the magnetically sensitive surface of the at least one magnetoelectric transducer may be arranged at a position overlapping with the side surface of the conductor portion having the at least one slit when viewed from a direction intersecting the thickness direction of the at least one magnetoelectric transducer.

[0026] In any of the above current sensors, the at least one magneto-electric conversion element may be a Hall element that detects a longitudinal magnetic field in a thickness direction of the conductor portion.

[0027] In any of the current sensors, the at least one magneto-electric conversion element may be a magnetoresistive element that detects a transverse magnetic field in a direction along the second surface of the conductor portion.

[0028] A current sensor according to one embodiment of the present invention may include at least one magnetoelectric conversion element. The current sensor includes a first lead frame, the first lead frame includes a first terminal portion and a conductor portion connected to the first terminal portion, and the measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion. The current sensor includes a signal processing IC, the signal processing IC is arranged on the second surface side opposite to the first surface of the conductor portion, has a circuit surface on which the at least one magnetoelectric conversion element is arranged and opposite to the second surface, and processes the signal output from the at least one magnetoelectric conversion element. The current sensor includes a sealing portion, the sealing portion sealing the at least one magnetoelectric conversion element, the conductor portion and the signal processing IC. The conductor portion includes: a first portion connected to the first terminal portion; and a second portion arranged opposite to the circuit surface of the signal processing IC, offset relative to the first portion in the direction away from the circuit surface of the signal processing IC in the thickness direction and connected to the first portion. The second portion has a third corner portion, the third corner portion is located between a second end surface on a side connected to the first portion and a first surface on an opposite side of a second surface opposite to the circuit surface of the signal processing IC. The area of ​​an outer surface of the third corner portion is larger than the area of ​​an outer surface of a fourth corner portion, the fourth corner portion is located between the second end surface of the second portion and a first surface of the first portion on the same side as the first surface of the second portion.

[0029] In any of the current sensors, the second end surface of the second portion may have a shear surface.

[0030] A current sensor according to one embodiment of the present invention may include at least one magnetoelectric conversion element. The current sensor includes a first lead frame, the first lead frame includes a first terminal portion and a conductor portion connected to the first terminal portion, and the measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion. The current sensor includes a signal processing IC, the signal processing IC has a circuit surface on which the at least one magnetoelectric conversion element is configured, and processes the signal output from the at least one magnetoelectric conversion element. The current sensor includes a second lead frame, the second lead frame includes a second terminal portion and a support portion, and is electrically insulated from the first lead frame, the second terminal portion is arranged opposite to the first terminal portion across the signal processing IC when viewed from above and is electrically connected to the signal processing IC, and the support portion supports the signal processing IC using the first surface. The current sensor includes a sealing portion, and the sealing portion seals the at least one magnetoelectric conversion element, the conductor portion, the signal processing IC, and the support portion. The conductor portion has a first shear surface, which is located closer to the first terminal portion than the signal processing IC when viewed from above, faces the second terminal portion, and is a step or end surface having the shear surface. The area of ​​the outer surface of the fifth corner among the corners of the first shear surface is larger than the area of ​​the outer surface of the sixth corner. The fifth corner is located on the side of the second surface opposite to the first surface of the support portion, and the sixth corner is located on the side away from the second surface.

[0031] A current sensor according to one embodiment of the present invention may include at least one magnetoelectric conversion element. The current sensor includes a first lead frame, the first lead frame includes a first terminal portion and a conductor portion connected to the first terminal portion, and the measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion. The current sensor includes a signal processing IC, the signal processing IC has a circuit surface on which the at least one magnetoelectric conversion element is configured, and processes the signal output from the at least one magnetoelectric conversion element. The current sensor includes a second lead frame, the second lead frame includes a second terminal portion and a support portion, and is electrically insulated from the first lead frame, the second terminal portion is arranged opposite to the first terminal portion across the signal processing IC when viewed from above and is electrically connected to the signal processing IC, and the support portion supports the signal processing IC using the first surface. The current sensor includes a sealing portion, and the sealing portion seals the at least one magnetoelectric conversion element, the conductor portion, the signal processing IC, and the support portion. The support portion has a seventh corner and an eighth corner, the seventh corner is located between the first surface supporting the signal processing IC and the second end surface on the first terminal portion side, and the eighth corner is located between the second surface on the opposite side of the first surface supporting the signal processing IC and the second end surface. The area of ​​the outer surface of the seventh corner is larger than the area of ​​the outer surface of the eighth corner.

[0032] A current sensor according to one embodiment of the present invention may include at least one magnetoelectric converter. The current sensor includes a first lead frame, the first lead frame includes a first terminal portion and a conductor portion connected to the first terminal portion, and the measurement current measured by the at least one magnetoelectric converter flows through the first terminal portion and the conductor portion. The current sensor includes a signal processing portion, the signal processing portion is arranged on the second surface side opposite to the first surface of the conductor portion, has a circuit surface opposite to the second surface of the conductor portion, the at least one magnetoelectric converter is arranged on the circuit surface, and processes the signal output from the at least one magnetoelectric converter. The current sensor includes a second lead frame, the second lead frame includes a support portion and a second terminal portion, the support portion supports the support surface on the opposite side of the circuit surface of the signal processing portion using the first surface, the second terminal portion is connected to the support portion, and outputs the signal from the signal processing portion. The current sensor includes a sealing portion, the sealing portion seals the at least one magnetoelectric converter, the conductor portion, the signal processing portion, and the support portion. The conductor portion may include: a first corner portion located between a first end surface on the opposite side to the side connected to the first terminal portion and a second surface opposite to the signal processing portion; and a second corner portion located between the first end surface and the first surface of the conductor portion. The support portion may include: a third corner portion located between a second end surface on the opposite side to the side connected to the second terminal portion and the first surface of the support portion supporting the signal processing portion; and a fourth corner portion located between the second end surface and a second surface on the opposite side to the first surface of the support portion. The area of ​​the outer surface of the second corner portion is larger than the area of ​​the outer surface of the first corner portion, or the area of ​​the outer surface of the fourth corner portion is larger than the area of ​​the outer surface of the third corner portion.

[0033] In the current sensor, the outer surface area of ​​the second corner portion may be larger than that of the first corner portion, and the conductor portion may be bent to approach the second surface of the support portion in the sealing portion and connected to the first terminal portion.

[0034] In any of the current sensors, the area of ​​the outer surface of the second corner portion may be larger than the area of ​​the outer surface of the first corner portion, and the conductor portion may be bent and connected to the first terminal portion in such a manner that the surface of the second surface of the conductor portion that is connected to the first terminal portion is closer to the second surface on the second surface side of the supporting portion in the sealing portion than the surface of the second surface of the conductor portion that is opposite to the circuit surface of the signal processing portion, and the second surface of the conductor portion that is connected to the first terminal portion is more than half the thickness of the conductor portion.

[0035] In any of the current sensors, the outer surface area of ​​the fourth corner portion may be larger than that of the third corner portion, and the support portion may be bent to approach the first surface of the conductor portion in the sealing portion on the first surface side to be connected to the second terminal portion.

[0036] In any of the current sensors, the area of ​​the outer surface of the fourth corner portion may be larger than the area of ​​the third corner portion, and the supporting portion may be bent and connected to the second terminal portion in such a manner that the surface of the first surface of the supporting portion that is connected to the second terminal portion is closer to the first surface on the first surface side of the conductor portion in the sealing portion than the surface of the first surface of the supporting portion that supports the signal processing portion by more than half the thickness of the supporting portion.

[0037] In any of the current sensors, the area of ​​the outer surface of the second corner portion may be larger than the area of ​​the outer surface of the first corner portion, and the second corner portion may be a chamfered surface.

[0038] In any of the current sensors, the outer surface area of ​​the fourth corner portion may be larger than the outer surface area of ​​the third corner portion, and the fourth corner portion may be a chamfered surface.

[0039] The linear expansion coefficient of the first lead frame or the second lead frame may be larger than the linear expansion coefficient of the mold resin constituting the sealing portion at a predetermined minimum temperature.

[0040] In any of the current sensors, when the area of ​​the outer surface of the second corner is larger than the area of ​​the outer surface of the first corner, either a width of the second corner in the direction along the first surface of the conductor portion when projected in the direction along the first end surface, or a width of the second corner in the direction along the first end surface when projected in the direction along the first surface of the conductor portion is larger than 15 μm and shorter than the thickness of the conductor portion.

[0041] In any of the above current sensors, the sealing portion may be formed of a mold resin, the mold resin may contain a filler having a diameter of 20 μm or more, and a filling rate of the filler may be 60% or more.

[0042] In any of the current sensors, the area of ​​the outer surface of the fourth corner may be larger than the area of ​​the outer surface of the third corner, and either the width of the fourth corner in the direction along the second surface of the support portion when projecting the fourth corner in the direction along the second end surface, or the width of the fourth corner in the direction along the second surface of the support portion when projecting the fourth corner in the direction along the second surface of the support portion is larger than 15 μm and shorter than the thickness of the support portion.

[0043] In any of the above current sensors, the sealing portion may be formed of a mold resin, the mold resin may contain a filler having a diameter of 20 μm or more, and a filling rate of the filler may be 60% or more.

[0044] In any of the above current sensors, the conductor portion may be covered with a mold resin constituting the sealing portion and may have no interface with any part other than the mold resin.

[0045] In any of the current sensors, the first lead frame may be thicker than the second lead frame.

[0046] In any of the current sensors, the first terminal portion may protrude from a first side surface of the sealing portion, and the second terminal portion may protrude from a second side surface opposite to the first side surface of the sealing portion in a first direction. The area of ​​the outer surface of the second corner portion is larger than the area of ​​the outer surface of the first corner portion, and when the distance between the first surface of the conductor portion on the first side of the sealing portion and the first surface of the conductor portion is set to t1, the width of the portion of the conductor portion opposite to the signal processing portion in the second direction intersecting the first direction along the first surface of the conductor portion is set to l1, the distance between the second surface of the conductor portion and the circuit surface of the signal processing portion is set to t2, and the width in the second direction along the circuit surface of the signal processing portion is set to l2, then l1 / t1>l2 / t2 is satisfied.

[0047] In any of the current sensors, the first terminal portion may protrude from a first side surface of the sealing portion, and the second terminal portion may protrude from a second side surface opposite to the first side surface of the sealing portion in a first direction. The area of ​​the outer surface of the fourth corner portion is larger than the area of ​​the outer surface of the third corner portion, and when the distance between the second surface of the second surface side of the support portion in the sealing portion and the second surface of the support portion is set to t3, the width of the portion of the support portion supporting the signal processing portion in the second direction along the second surface of the support portion and intersecting the first direction is set to l3, the distance between the second surface of the conductor portion and the circuit surface of the signal processing portion is set to t2, and the width along the second direction of the circuit surface of the signal processing portion is set to l2, then l3 / t3>l2 / t2 is satisfied.

[0048] In any of the current sensors, the signal processing unit may be an IC chip. The at least one magnetoelectric conversion unit may be a magnetoelectric conversion element independent of the IC chip. The magnetoelectric conversion element has a magnetically sensitive surface that protrudes from a surface of the IC chip that faces the conductor unit.

[0049] In any of the current sensors, the signal processing unit may be an IC chip, the magneto-electric converter may be built in the IC chip, and a magnetically sensitive surface of the magneto-electric converter may not protrude from a surface of the IC chip that faces the conductor.

[0050] In addition, the above summary of the invention does not list all the features of the present invention. In addition, sub-combinations of these feature groups can also constitute the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1A This is a schematic plan view of the current sensor according to the first embodiment as viewed from the top surface side (Z-axis direction).

[0052] Figure 1B yes Figure 1A AA line cross-sectional view of the current sensor shown.

[0053] Figure 1C It is a schematic plan view of a current sensor according to a modified example of the first embodiment, as viewed from the top surface side (Z-axis direction).

[0054] Figure 1D yes Figure 1C AA line cross-sectional view of the current sensor shown.

[0055] Figure 2 Yes means Figure 1B FIG. 3 is a diagram showing an example of an enlarged view of a surrounded portion indicated by reference numeral 300 .

[0056] Figure 3A This is a diagram showing an example of a simulation result of an electric field intensity when a potential difference is provided between the terminal portion 142 and the terminal portion 152 in a structure in which the first corner portion 1401 is not chamfered.

[0057] Figure 3B This is a diagram showing an example of a simulation result of an electric field when a potential difference is provided between the terminal portion 142 and the terminal portion 152 in a structure in which the first corner portion 1401 is chamfered.

[0058] Figure 4 This is a diagram showing an example of the relationship between the size of the chamfer and the maximum electric field.

[0059] Figure 5A 14 is a diagram showing an example of the chamfered shape of the first corner portion 1401 .

[0060] Figure 5B 14 is a diagram showing an example of the chamfered shape of the first corner portion 1401 .

[0061] Figure 5C 14 is a diagram showing an example of the chamfered shape of the first corner portion 1401 .

[0062] Fig. 6A This is a diagram showing an example of a simulation result of a corresponding stress in a structure where the third corner portion 1403 is not chamfered.

[0063] Figure 6B This is a diagram showing an example of a simulation result of a corresponding stress in a structure in which the third corner portion 1403 is chamfered.

[0064] Figure 7 This is a diagram showing an example of the relationship between the size of the chamfer and the size of the corresponding stress.

[0065] Fig. 8A 14 is a diagram showing an example of a simulation result of thermal stress in a structure in which the fifth corner 1405 and the seventh corner 1501 are not chamfered.

[0066] Figure 8B An example of simulation results of thermal stress in a structure in which the fifth corner 1405 and the seventh corner 1501 are chamfered is shown.

[0067] Fig. 9 This is a diagram showing an example of an enlarged view of the vicinity of a conductor portion of the current sensor according to the second embodiment.

[0068] Fig.10 This is a diagram showing an example of an enlarged view of the vicinity of a conductor portion of the current sensor according to the third embodiment.

[0069] Fig.11 It is a schematic plan view of the current sensor according to the fourth embodiment as viewed from the top surface side (Z-axis direction).

[0070] Fig.12 This is a diagram showing an example of an enlarged view of the vicinity of a conductor portion of the current sensor according to the fourth embodiment.

[0071] Fig.13A It is a schematic plan view of the current sensor according to the fifth embodiment as viewed from the top surface side (Z-axis direction).

[0072] Fig. 13B yes Fig.13A AA line cross-sectional view of the current sensor shown.

[0073] Fig. 13C yes Fig.13A A BB line cross-sectional view of the current sensor shown.

[0074] Fig.14A is from Fig.13A This is a schematic plan view of a current sensor according to a modified example of the embodiment shown, as viewed from the top surface side (Z-axis direction).

[0075] Fig. 14B yes Fig.14AAA line cross-sectional view of the current sensor shown.

[0076] Fig.15 express Fig. 13B An example of an enlarged view of the enclosed portion indicated by reference numeral 300 is shown.

[0077] Fig.16A 1 is a diagram showing an example of the chamfered shape of the second corner portion.

[0078] Fig. 16B 1 is a diagram showing an example of the chamfered shape of the second corner portion.

[0079] Fig. 16C 1 is a diagram showing an example of the chamfered shape of the second corner portion.

[0080] Fig.17A This is a diagram showing an example of a simulation result of thermal stress when a current sensor is placed in an environment of -65 degrees, the minimum temperature required in a durability test, in a structure in which the second corner portion is not chamfered.

[0081] Fig. 17B This is a diagram showing an example of a simulation result of thermal stress when a current sensor is placed in an environment of -65 degrees, the minimum temperature required in a durability test, in a structure in which the second corner portion is chamfered.

[0082] Fig.18A This is a cross-sectional view of the current sensor according to the sixth embodiment as viewed from the X-axis direction.

[0083] Fig.18B This is a cross-sectional view of the current sensor according to the sixth embodiment as viewed from the Y-axis direction.

[0084] Fig.19 express Fig.18A An example of an enlarged view of the enclosed portion indicated by reference numeral 300 is shown.

[0085] Fig. 20 1 is a diagram showing an example of the chamfered shape of the fourth corner.

[0086] [Explanation of Reference Numerals]

[0087] 10Current sensor

[0088] 20a, 20b magnetoelectric conversion element

[0089] 22, 22a, 22b, 108 wires

[0090] 100 signal processing IC

[0091] 130 Sealing part

[0092] 140, 150 lead frame

[0093] 141 Conductor

[0094] 141a, 141b Slit portion

[0095] 142 Terminals

[0096] 142a, 142b, 152a terminals

[0097] 144, 155 steps

[0098] 152 Terminals

[0099] 151, 154 support part

[0100] 155 Steps

[0101] 1401 First Corner

[0102] 1402 Second Corner

[0103] 1403, 1503 third corner

[0104] 1404, 1504 Fourth Corner

[0105] 1405 Fifth Corner

[0106] 1406 Sixth Corner

[0107] 1411 Part 1

[0108] 1412 Part 2

[0109] 1501 Seventh Corner

[0110] 1502 Eighth Corner DETAILED DESCRIPTION

[0111] 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, the combination of features described in the embodiments is not necessarily all essential to the solution means of the invention.

[0112] 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 This is a schematic plan view of the current sensor 10 according to the first embodiment as 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.

[0113] 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 one of the X-axis, Y-axis, and Z-axis is orthogonal to the other axes.

[0114] 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 .

[0115] The lead frame 140 includes a conductor portion 141 and a terminal portion 142. The terminal portion 142 includes a pair of terminals 142a and 142b. The conductor portion 141 is sealed in the sealing portion 130 and partially surrounds the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b. The measurement current flows through the terminal portion 142 and the conductor portion 141. The pair of terminals 142a and 142b are physically integrated with the conductor portion 141 and exposed to the outside of the sealing portion 130. The lead frame 140 is an example of a first lead frame.

[0116] The lead frame 140 does not need to be manufactured in such a manner that the conductor portion 141 and the terminal portion 142 are formed by connecting a plurality of metal plates, and may be manufactured using a single-piece metal member.

[0117] The lead frame 150 includes a support portion 154 and a terminal portion 152. The terminal portion 152 includes a plurality of terminals 152a. The support portion 154 is sealed in the sealing portion 130 and supports the signal processing IC 100. A portion of the plurality of terminals 152a is physically integrated with the support portion 154. At least a portion of each 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 second lead frame. The lead frame 140 and the lead frame 150 can be made of a conductive material having copper as a main component. The support portion 154 can also be made of an insulating member such as a metal plate independent of the lead frame 150, a plate made of a semiconductor, or a chip mounting film.

[0118] 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 direction intersecting the thickness direction may be a direction along a plane (XY plane) orthogonal to the thickness direction. 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 on the opposite side of the side surface 130a of the sealing portion 130. Figure 1BAs shown, a pair of terminals 142a, 142b and a plurality of terminals 152a may protrude outward from different heights in the thickness direction of the sealing portion 130 of the side surfaces 130a and 130b of the sealing portion 130 that are opposite to each other. The surfaces 1521 of the plurality of terminals 152a on the same side as the surface 100a of the signal processing IC 100 may be located at the same height as the surfaces 1421 of the pair of terminals 142a, 142b on the same side as the surface 100a of the signal processing IC 100 in the thickness direction (Z-axis direction) of the sealing portion 130. Alternatively, the surfaces 1521 of the plurality of terminals 152a may be located below the surfaces 1421 of the pair of terminals 142a, 142b in the thickness direction of the sealing portion 130.

[0119] That is, the height of the surface 1521 of the plurality of terminals 152a at the position intersecting the side surface 130a of the sealing portion 130 on the same side as the surface 100a of the signal processing IC 100 in the thickness direction (Z-axis direction) of the sealing portion 130 and the height of the surface 1421 of the pair of terminals 142a, 142b at the position intersecting the side surface 130b of the sealing portion 130 on the same side as the surface 100a of the signal processing IC 100 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 intersecting the side surface 130a 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 intersecting the side surface 130b of the sealing portion 130 in the thickness direction (Z-axis direction) of the sealing portion 130.

[0120] A pair of terminals 142a, 142b protrude from the side 130a toward the negative side in the Y-axis direction, and then bend toward the negative side in the Z-axis direction. Multiple terminals 152a protrude from the side 130b toward the positive side in the Y-axis direction, and then bend toward the negative side in the Z-axis direction. A pair of terminals 142a, 142b may also protrude from the side 130a toward the negative side in the Y-axis direction, and then bend toward the positive side in the Z-axis direction. Multiple terminals 152a may also protrude from the side 130b toward the positive side in the Y-axis direction, and then bend toward the positive side in the Z-axis direction. A pair of terminals 142a, 142b and multiple terminals 152a may also not be bent. That is, a pair of terminals 142a, 142b may also protrude from the side 130a toward the negative side in the Y-axis direction, and not bend 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 and the negative side in the Z-axis direction.

[0121] The support portion 154 may have a step portion 155 in which the portion supporting the signal processing IC 100 is recessed in the direction away from the conductor portion 141 (the 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 to the surface 154a of the portion supporting the signal processing IC 100 via an adhesive layer. The adhesive layer may be a chip mounting film. The lead frame 140 has a step portion 144 in which the relative portion opposite to the signal processing IC 100 protrudes in the thickness direction in the direction away from the signal processing IC 100. The step portion 144 is an example of a second step portion. The step portion 155 and the step portion 144 may be formed by performing a half-punching process on the lead frame 150 and the lead frame 140. In this case, there are shear surfaces on the step portion 155 and the step portion 144.

[0122] The conductor portion 141 has two slit portions 141a and 141b. The magnetoelectric conversion element 20a is arranged in the slit portion 141a when viewed from above, so that it is partially surrounded by the conductor portion 141. The magnetoelectric conversion element 20b is arranged in the slit portion 141b when viewed from above, so that it is partially surrounded by the conductor portion 141. The magnetoelectric conversion elements 20a and 20b can be fixed to the circuit surface of the signal processing IC100 by chip bonding, and are electrically connected to the signal processing IC100 by wire bonding. That is, the magnetoelectric conversion elements 20a and 20b can be electrically connected to the signal processing IC100 via a plurality of wires 22a and 22b. The magnetoelectric conversion elements 20a and 20b can also be electrically connected to the signal processing IC100 by flip chip bonding. The magnetoelectric conversion elements 20a and 20b output the signal processed by the signal processing IC100 to the signal processing IC100. The magnetoelectric transducers 20a and 20b may be configured independently of the signal processing IC 100. That is, the magnetoelectric transducers 20a and 20b may be configured by a chip different from the chip configuring the signal processing IC 100. The magnetoelectric transducers 20a and 20b may also be built in a chip configuring the signal processing IC 100.

[0123] The magnetically sensitive surfaces of the magnetoelectric conversion elements 20a and 20b can be arranged at positions overlapping with the side surfaces provided with the slit portions 141a and 141b when viewed from a direction (X-axis direction or Y-axis direction) intersecting the thickness direction (Z-axis direction) of the magnetoelectric conversion elements 20a and 20b.

[0124] The signal processing IC 100 is electrically connected to the plurality of terminals 152a via the wires 108. The wires 22a, 22b and the wires 108 can be formed of a conductive material mainly composed of Au, Ag, Cu, or Al.

[0125] The magnetoelectric transducers 20a and 20b may protrude from the surface 100a of the signal processing IC 100 so that the magnetosensitive surfaces of the magnetoelectric transducers 20a and 20b overlap with the conductor 141 in a side view. This can improve the sensitivity of the magnetoelectric transducers 20a and 20b.

[0126] 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 through 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.

[0127] The magnetoelectric conversion elements 20a and 20b may have a substrate made of silicon or a compound semiconductor and a magnetoelectric conversion portion disposed on the substrate. The thickness of the substrate is adjusted by grinding the surface on the negative side in the Z-axis direction. Since the magnetic field in the Z-axis direction is detected, for example, a Hall element that detects the longitudinal magnetic field in the thickness direction of the conductor portion 141 is suitable 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 a magnetic field in any axial direction on the XY plane, for example, if they are arranged at a position to detect a magnetic field in the X-axis direction, a magnetoresistive element or a fluxgate element is suitable as the magnetoelectric conversion elements 20a and 20b. More specifically, it can be arranged to overlap with the conductor 141 when viewed from above in the Z-axis direction. Figure 1C and Figure 1D This is an example of the current sensor 10 in which a magneto-electric conversion element is arranged at a position for detecting a magnetic field in the X-axis direction. Figure 1C The internal structure of a semiconductor package in which the current sensor 10 functions as a modification of the first embodiment is shown. Figure 1C It is a schematic plan view of the current sensor 10 according to the modified example of the first embodiment, as viewed from the top surface side (Z-axis direction). Figure 1D yes Figure 1C AA line cross-sectional view of the current sensor 10 shown. In the current sensor 10 according to the modification of the first embodiment, the magneto-electric conversion elements 20 a and 20 b are built in a chip constituting the signal processing IC 100 .

[0128] The signal processing IC100 is a large-scale integrated circuit (LSI). The signal processing IC100 is a monolithic IC. More specifically, the signal processing IC100 is a signal processing circuit composed of a Si monolithic semiconductor formed on a Si substrate. The signal processing IC100 has a circuit surface configured with magnetoelectric conversion elements 20a, 20b. In the first embodiment, the circuit surface is a surface 100a corresponding to the top surface of the semiconductor package constituting the signal processing IC100. The surface 100a is an example of the first surface of the signal processing IC100. The signal processing circuit processes an output signal corresponding to the magnitude of the magnetic field output from the magnetoelectric conversion elements 20a, 20b. The signal processing circuit corrects the measured current flowing through the conductor portion 141 based on the output signal, and outputs an output signal representing an accurate current value via the terminal 152a. The signal processing circuit reduces the noise components contained in the output signals of the magnetoelectric conversion element 20a and the output signals of the magnetoelectric conversion element 20b based on the difference between the output signals of the magnetoelectric conversion element 20a and the output signals of the magnetoelectric conversion element 20b, amplifies the output signals of the magnetoelectric conversion element 20a and the output signals 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 signals, and outputs an output signal representing the current value.

[0129] The sealing unit 130 seals the magnetoelectric conversion elements 20a and 20b, the conductor 141, the support 154, the signal processing IC 100, the wires 22a and 22b, and the wire 108 with a molding resin. The molding resin is composed of, for example, a thermosetting epoxy resin containing silicon dioxide, and can be formed into a semiconductor package by transfer molding.

[0130] Figure 2 express Figure 1B 1 is an example of an enlarged view of the enclosed portion indicated by reference numeral 300. The conductor portion 141 includes a first portion 1411 connected to the terminal portion 142, and a second portion 1412 arranged opposite to the surface 100a of the signal processing IC 100 and connected to the first portion 1411 by being offset from the first portion 1411 in the direction away from the surface 100a of the signal processing IC 100 in the thickness direction. The second portion 1412 is offset from the first portion 1411 by performing a half-punching process on the conductor portion 141.

[0131] Second portion 1412 has first corner 1401 between first end face 1412c on the opposite side to the side connected to terminal portion 142 and second face 1412b facing signal processing IC 100, and second corner 1402 between first end face 1412c and first face 1412a on the opposite side to second face 1412b facing signal processing IC 100. Second portion 1412 has third corner 1403 between second end face 1412d on the side connected to first portion 1411 and first face 1412a on the opposite side to second face 1412b facing face 100a of signal processing IC 100. First portion 1411 has fifth corner 1405 between third end face 1411c on the side connected to second portion 1412 and second face 1411b on the same side as second face 1412b of second portion 1412.

[0132] The supporting portion 154 of the lead frame 150 has: a seventh corner portion 1501, located between a surface 154a supporting the signal processing IC100 and a fourth end surface 154c on the terminal portion 142 side; and an eighth corner portion 1502, located between a second surface 154b on the opposite side of the surface 154a supporting the signal processing IC100 and the fourth end surface 154c.

[0133] Here, the first corner 1401, the third corner 1403, the fifth corner 1405, and the seventh corner 1501 are chamfered surfaces. The area of ​​the outer surface of the first corner 1401 is greater than the area of ​​the outer surface of the second corner 1402. The area of ​​the outer surface of the first corner 1401 is the area of ​​the chamfered surface. The area of ​​the outer surface of the first corner 1401 is the area of ​​the outer surface defined from the boundary between the second surface 1412b and the first corner 1401 to the boundary between the first end surface 1412c and the first corner 1401. The area of ​​the outer surface of the second corner 1402 is the area of ​​the outer surface defined from the boundary between the first end surface 1412c and the second corner 1402 to the boundary between the first surface 1412a and the second corner. The second corner 1402 may be a substantially straight line along the X-axis direction. The area of ​​the outer surface of the second corner 1402 may be substantially zero.

[0134] The area of ​​the outer surface of the third corner 1403 is larger than the area of ​​the outer surface of the fourth corner 1404 between the second end surface 1412d of the second portion 1412 and the first surface 1411a of the first portion 1411 on the same side as the first surface 1412a of the second portion 1412. The area of ​​the outer surface of the third corner 1403 is the area of ​​the chamfered surface. The area of ​​the outer surface of the third corner 1403 is the area of ​​the outer surface defined from the boundary between the first surface 1412a and the third corner 1403 to the boundary between the second end surface 1412d and the third corner 1403. The area of ​​the outer surface of the fourth corner 1404 is the area of ​​the outer surface defined from the boundary between the second end surface 1412d and the fourth corner 1404 to the boundary between the first surface 1411a and the fourth corner 1404. The fourth corner 1404 may be a substantially straight line along the X-axis direction. The area of ​​the outer surface of the fourth corner 1404 may be substantially zero.

[0135] The area of ​​the outer surface of the fifth corner 1405 is larger than the area of ​​the outer surface of the sixth corner 1406 between the third end face 1411c of the first portion 1411 and the second face 1412b of the second portion 1412. The area of ​​the outer surface of the fifth corner 1405 is the area of ​​the chamfered surface. The area of ​​the outer surface of the fifth corner 1405 is the area of ​​the outer surface defined from the boundary between the third end face 1411c and the fifth corner 1405 to the boundary between the fifth corner 1405 and the second face 1411b. The area of ​​the outer surface of the sixth corner 1406 is the area of ​​the outer surface defined from the boundary between the second face 1412b and the sixth corner 1406 to the boundary between the sixth corner 1406 and the third end face 1411c. The sixth corner 1406 may be a substantially straight line along the X-axis direction. The area of ​​the outer surface of the sixth corner 1406 may be substantially zero.

[0136] The area of ​​the outer surface of the seventh corner 1501 is greater than the area of ​​the outer surface of the eighth corner 1502. The area of ​​the outer surface of the seventh corner 1501 is the area of ​​the chamfered surface. The area of ​​the outer surface of the seventh corner 1501 is the area of ​​the outer surface defined from the boundary between the surface 154a and the seventh corner 1501 to the boundary between the seventh corner 1501 and the fourth end face 154c. The area of ​​the outer surface of the eighth corner 1502 is the area of ​​the outer surface defined from the boundary between the surface 154b and the eighth corner 1502 to the boundary between the eighth corner 1502 and the fourth end face 154c. The eighth corner 1502 may be a substantially straight line along the X-axis direction. The area of ​​the outer surface of the eighth corner 1502 may be substantially zero.

[0137] By chamfering the first corner 1401, the third corner 1403, the fifth corner 1405, and the seventh corner 1501, the concentration of electric field and stress near the corners can be suppressed, thereby improving the durability of the current sensor 10. In other words, the occurrence of a withstand voltage failure due to the short distance between the signal processing IC 100 and the conductor 141 can be suppressed.

[0138] The chamfered shapes of the first corner 1401, the third corner 1403, the fifth corner 1405, and the seventh corner 1501 may be any shape, or may be composed of a plurality of surfaces formed by combining a plurality of substantially flat surfaces. Figure 5A As shown, it can be composed of a substantially flat surface, or it can be composed of a substantially flat surface. Figure 5B As shown in the figure, it is composed of one side of the R surface (curved surface), and it can also be Figure 5C As shown, it is composed of two surfaces formed by combining two roughly flat surfaces. Figure 5B As shown, when the first corner 1401, the third corner 1403, the fifth corner 1405 and the seventh corner 1501 are R-surfaces, the areas of the outer surfaces of the first corner 1401, the third corner 1403, the fifth corner 1405 and the seventh corner 1501 are the areas of the curved surface portions. The boundaries between the first corner 1401, the third corner 1403, the fifth corner 1405 and the seventh corner 1501 and their respective adjacent surfaces are the portions where their respective curved surfaces begin.

[0139] The following describes the reason why concentration of electric field or concentration of stress near the corner portions can be suppressed by chamfering the first corner portion 1401 , the third corner portion 1403 , the fifth corner portion 1405 , and the seventh corner portion 1501 .

[0140] Figure 3A An example of simulation results of electric field strength when a potential difference is provided between the terminal portion 142 and the terminal portion 152 in a structure where the first corner portion 1401 is not chamfered is shown. The terminal portion 142 may become a high voltage during the application of the current to be measured. Figure 3B An example of simulation results of electric field intensity when a potential difference is provided between the terminal portion 142 and the terminal portion 152 in a structure in which the first corner portion 1401 is chamfered is shown. Figure 3A and Figure 3B A curve showing the contours of the electric field. Figure 3A and Figure 3B It can be seen that near the first corner 1401, Figure 3A The contour ratio of the electric field shown is Figure 3B That is, it can be seen that the electric field is easily concentrated near the first corner 1401 when chamfering is not performed.

[0141] When the lead frame 140 on the current conductor side and the lead frame 150 on the signal terminal side are configured to overlap in the thickness direction, the portion where the electric field is most likely to concentrate is the first corner 1401 of the second portion 1412 in the conductor portion 141 of the lead frame 140 on the current conductor side. Therefore, by chamfering the first corner 1401 of the second portion 1412, the concentration of the electric field can be suppressed, and the durability of the current sensor 10 can be improved.

[0142] Figure 4 This is an example showing the relationship between the chamfer size and the maximum electric field. Figure 4 As shown, even if chamfering is performed by only about 25 μm, the maximum electric field can be significantly reduced.

[0143] The molded resin constituting the sealing portion 130 contains a large amount of filler. The molded resin contains filler having a filler diameter (diameter) of 20 μm or more, and the filling rate of the filler is 60% or more. The mode of the diameter of the filler contained in the molded resin is about 20 μm. Furthermore, in the case of a three-dimensional sphere having a diameter of about 20 μm, when observed on the line segment of the chamfered portion, the dimension is reduced to one dimension, so the filler diameter is 15 μm (20 μm×(√3 / 2) 2 ). Moreover, when the filler is about to generate discharge, it blocks the discharge path, making it difficult to generate discharge. Therefore, if the width of the chamfered surface is equal to or greater than the filler diameter, the possibility of filler existing in the chamfered portion becomes very high, making it difficult to generate discharge. In addition, Figure 4 The simulation results shown are the results of simulations performed on the assumption that the filler is uniformly contained in the molding resin.

[0144] Figure 5A , Figure 5B and Figure 5C An example of the chamfered shape of the first corner portion 1401 is shown. The width of the first direction Y axis when the first corner portion 1401 is projected in the Z-axis direction is set as width w1, and the width of the first corner portion 1401 in the Z-axis direction along the first end surface 1412c when the first corner portion 1401 is projected in the Y-axis direction along the second surface 1412b of the conductor portion 141 is set as width w2. In this case, either the width w1 or the width w2 is greater than 15μm and shorter than the thickness of the conductor portion 141. As a result, as described above, the possibility of the presence of filler in the chamfered portion can be increased.

[0145] In addition, even when the first corner 1401 is chamfered, electric field concentration occurs at the corner. In particular, the electric field is easily concentrated at the corner near the signal processing IC 100. Figure 5C As shown in FIG. 14 , the width w1 is preferably longer than the width w2 . This can further reduce the concentration of the electric field near the first corner portion 1401 .

[0146] As described above, the second portion 1412 is offset relative to the first portion 1411 by performing the half-punching process on the conductor portion 141. By offsetting the second portion 1412 relative to the first portion 1411 by the half-punching process, the processing accuracy of the conductor portion 141 is improved. Therefore, even if the conductor portion 141 is arranged close to the signal processing IC 100, the possibility of the conductor portion 141 contacting the signal processing IC 100 due to manufacturing errors during the manufacturing process can be reduced.

[0147] On the other hand, for example, in the manufacturing process of the current sensor 10, stress may be generated in the sealing portion 130 due to the lead frame 140 being pressed or the current sensor 10 vibrating in a state where the current sensor 10 is mounted. In this case, stress is concentrated on the corners of the lead frame 140. In particular, stress is concentrated near the third corner 1403, which is a portion close to the outer surface of the sealing portion 130. The third corner 1403 formed by the half-punching process is sharper than the case of other processing methods such as bending to form a step. Therefore, cracks are more likely to occur in the sealing portion 130 near the third corner 1403 than in other portions.

[0148] Fig. 6A and Figure 6B The simulation results of the equivalent stress near the third corner 1403 are shown. Fig. 6A An example of simulation results of the equivalent stress in a structure where the third corner portion 1403 is not chamfered is shown. Figure 6B An example of simulation results showing the equivalent stress in a structure where the third corner 1403 is chamfered. The denser the stress contour lines are, the more concentrated the stress is. Fig. 6A and Figure 6B As shown, it can be seen that by chamfering the third corner 1403, stress concentration near the third corner 1403 can be suppressed. In other words, by chamfering the third corner 1403, the generation of cracks can be suppressed.

[0149] Figure 7 This is an example showing the relationship between the size of the chamfer and the size of the equivalent stress. Figure 7 As shown, the larger the chamfer, the more it can reduce the corresponding stress.

[0150] Here, in the case where a small crack is generated from a location with considerable stress, it is important to improve the toughness of the location in order to suppress the progress of the crack. In the case where the interface between the filler and the base material in the molding resin is peeled off, since the peeling energy is high, by including the filler, the toughness can be improved for the cracking of the base material such as epoxy resin, which is a fragile material. Therefore, it is preferred that the interface between the filler and the base material exists in the chamfered area where stress is concentrated.

[0151] As described above, the molding resin contains a filler having a filler diameter (diameter) of 20 μm or more, and the filling rate of the filler is 60% or more. When observed on the line segment of the chamfered portion, the dimension is reduced to one dimension, so the filler diameter is about 15 μm. If the filling rate of the filler is considered to be 60% or more, then in the case where the surface is greater than 15 μm × 0.4 / 0.6 = 10 μm, there is an interface between the filler and the base material in the area chamfered with a probability higher than 60%. Therefore, it is preferred that the length of the edge of the chamfered surface is 10 μm or more, and it is preferred to ensure a one-dimensional filler diameter of 15 μm or more.

[0152] Therefore, it is preferable that either the width of the third corner portion 1403 in the direction (Y-axis direction) along the first surface 1412a on the opposite side of the second surface 1412b of the conductor portion 141 when projected in the direction (Z-axis direction) along the second end surface 1412d, or the width of the third corner portion 1403 in the direction (Y-axis direction) along the second end surface 1412d when projected in the direction (Y-axis direction) along the first surface 1412a of the conductor portion 141 is greater than 15 μm and shorter than the thickness of the conductor portion 141. Thus, the initial development of the crack can be suppressed, and the reliability of the current sensor 10 can be further improved.

[0153] In addition, if Figure 2 As shown, the offset S of the second portion 1412 relative to the first portion 1411 is preferably 0.6 times or less of the thickness H of the conductor 141. Thus, the amount of protrusion of the second portion 1412 relative to the first portion 1411 is reduced, and the concentration of stress on the mold resin can be alleviated.

[0154] Fig. 8A as well as Figure 8B FIG. 4 shows the distribution of thermal stress when the temperature around the current sensor 10 is lowered and the mold resin shrinks. Fig. 8A An example of simulation results of thermal stress in a structure where the fifth corner 1405 and the seventh corner 1501 are not chamfered is shown. Figure 8B An example of simulation results of thermal stress in a structure in which the fifth corner 1405 and the seventh corner 1501 are chamfered is shown.

[0155] like Fig. 8A and Figure 8B As shown, it can be seen that the concentration of thermal stress in the area P1 near the fifth corner 1405 and the area P2 of the seventh corner 1501 when the fifth corner 1405 and the seventh corner 1501 are chamfered is less severe than the concentration of thermal stress in the area P1 near the fifth corner 1405 and the area P2 of the seventh corner 1501 when the fifth corner 1405 and the seventh corner 1501 are not chamfered.

[0156] As in the case of the third corner portion 1403, it is preferred that either the width of the fifth corner portion 1405 in the direction along the second surface 1411b of the first portion 1411 (the Y-axis direction) when projecting the fifth corner portion 1405 in the direction along the third end surface 1411c (the Z-axis direction) or the width of the fifth corner portion 1405 in the direction along the third end surface 1411c when projecting the fifth corner portion 1405 in the direction along the second surface 1411b of the first portion 1411 is greater than 15 μm and shorter than the thickness of the conductor portion 141. Thus, the interface between the filler and the base material can be easily present near the corner portion where the thermal stress is concentrated, the initial development of the crack can be suppressed, and the reliability of the current sensor 10 can be further improved.

[0157] In the first embodiment, the current sensor 10 includes two magneto-electric transducers 20a and 20b. However, the current sensor 10 only needs to include one or more magneto-electric transducers.

[0158] In the above, in the current sensor 10 of the first embodiment, an example in which the first corner 1401, the third corner 1403, the fifth corner 1405, and the seventh corner 1501 are chamfered is described. However, even if the chamfered corner is only at least one of the first corner 1401, the third corner 1403, the fifth corner 1405, and the seventh corner 1501, the concentration of electric field or stress can be alleviated.

[0159] Fig. 9 An example of an enlarged view of the conductor part 141 and the vicinity of the current sensor 10 according to the second embodiment is shown. In the second embodiment, only the third corner 1403 of the conductor part 141 is chamfered. The area of ​​the outer surface of the third corner 1403 is larger than the area of ​​the outer surface of the fourth corner 1404 between the second end surface 1412d of the second part 1412 and the first surface 1411a of the first part 1411 on the same side as the first surface 1412a of the second part 1412. When the third corner 1403 is projected in the direction along the second end surface 1412d (Z-axis direction) in the direction along the first surface 1412a of the conductor part 141 (Y-axis direction), either one of the width of the third corner 1403 in the direction along the second end surface 1412d (Z-axis direction) and the width of the third corner 1403 in the direction along the first surface 1412d (Z-axis direction) in the direction along the first surface 1412a of the conductor part 141 (Y-axis direction) may be greater than 15 μm and shorter than the thickness of the conductor part 141. According to the current sensor 10 of the second embodiment, by chamfering the third corner portion 1403 , it is possible to suppress stress concentration near the third corner portion 1403 , and suppress the occurrence of cracks.

[0160] Fig.10An example of an enlarged view of the vicinity of the conductor portion 141 of the current sensor 10 according to the third embodiment is shown. In the third embodiment, only the fifth corner 1405 of the conductor portion 141 and the seventh corner 1501 of the indicator portion 154 are chamfered. In addition, only one of the fifth corner 1405 of the conductor portion 141 and the seventh corner 1501 of the indicator portion 154 may be chamfered. The area of ​​the outer surface of the fifth corner 1405 is larger than the area of ​​the outer surface of the sixth corner 1406 between the third end face 1411c of the first portion 1411 and the second face 1412b of the second portion 1412. The area of ​​the outer surface of the seventh corner 1501 is larger than the area of ​​the outer surface of the eighth corner 1502.

[0161] Preferably, either the width of the first portion 1411 in the direction along the second surface 1411b (Y-axis direction) when the fifth corner portion 1405 is projected in the direction along the third end surface 1411c (Z-axis direction), or the width of the fifth corner portion 1405 in the direction along the third end surface 1411c when the fifth corner portion 1405 is projected in the direction along the second surface 1411b of the first portion 1411 is larger than 15 μm and shorter than the thickness of the conductor portion 141.

[0162] Preferably, either the width of the seventh corner portion 1501 in the direction along the surface 154a of the support portion 154 (Y-axis direction) when the seventh corner portion 1501 is projected in the direction along the fourth end surface 154c (Z-axis direction), or the width of the seventh corner portion 1501 in the direction along the fourth end surface 154c of the support portion 154 when the seventh corner portion 1501 is projected in the direction along the surface 154a of the support portion 154 is greater than 15 μm and shorter than the thickness of the support portion 154.

[0163] According to the current sensor 10 of the third embodiment, the interface between the filler and the base material can be easily present near the corner where the thermal stress concentrates, and the initial progress of the crack can be suppressed, so that the reliability of the current sensor 10 can be further improved.

[0164] Fig.11 It is a schematic plan view of the current sensor 10 according to the fourth embodiment as viewed from the top surface side (Z-axis direction). Fig.12 express Fig.11 An example of an enlarged view of the vicinity of the conductor portion 141 in the AA line cross section of the current sensor shown.

[0165] The current sensor 10 of the fourth embodiment is different from the current sensors 10 of the first to third embodiments in that the conductor portion 141 does not have a slit portion surrounding the magneto-electric conversion elements 20 a and 20 b .

[0166] In the fourth embodiment, the conductor part 141 has a fifth corner 1405 located between a surface 1411b on the opposite side of the surface 1411a on the same side as the surface 154a of the support part 154 and a third end surface 1411c on the terminal part 152 side, and a sixth corner 1406 located between the surface 1411a of the conductor part 141 and the third end surface 1411c. The area of ​​the outer surface of the fifth corner 1405 is larger than the area of ​​the outer surface of the sixth corner 1406. When the fifth corner 1405 is projected in the direction (Z-axis direction) along the third end surface 1411c, and when the fifth corner 1405 is projected in the direction along the surface 1411b of the conductor part 141, the width of the fifth corner 1405 in the direction (Y-axis direction) along the third end surface 1411c is greater than 15 μm and shorter than the thickness of the conductor part 141.

[0167] In addition, the support portion 154 has a seventh corner portion 1501 located between a surface 154a supporting the signal processing IC 100 and a fourth end surface 154c on the terminal portion 142 side, and an eighth corner portion 1502 located between a surface 154b on the opposite side of the surface 154a supporting the signal processing IC 100 and the fourth end surface 154c. The area of ​​the outer surface of the seventh corner portion 1501 is larger than the area of ​​the outer surface of the eighth corner portion.

[0168] According to the current sensor 10 of the fourth embodiment, the interface between the filler and the base material can be easily present near the corner where the thermal stress concentrates, and the initial progress of the crack can be suppressed, so that the reliability of the current sensor 10 can be further improved.

[0169] Fig.13A , Fig. 13B as well as Fig. 13C The internal structure of a semiconductor package that functions as the current sensor 10 according to the fifth embodiment is shown. Fig.13A It is a schematic plan view of the current sensor 10 according to the fifth embodiment as viewed from the top surface side (Z-axis direction). Fig. 13B yes Fig.13A The current sensor 10 is shown in a cross-sectional view taken along line AA. Fig. 13C yes Fig.13A The BB line cross-sectional view of the current sensor 10 shown in FIG. Figure 1A and Figure 1B The components denoted by the same reference numerals as those described in the illustrated current sensor 10 may be omitted in description.

[0170] The current sensor 10 includes a signal processing IC 100 , magnetoelectric conversion elements 20 a and 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 . This point is the same as the current sensor 10 of the first embodiment.

[0171] The lead frame 150 includes a support portion 151 and a terminal portion 152. The terminal portion 152 includes a plurality of terminals 152a. The support portion 151 is sealed in the sealing portion 130 and supports the signal processing IC 100. A portion of the plurality of terminals 152a is physically integrated with the support portion 151. At least a portion of each 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 second lead frame. The lead frame 140 and the lead frame 150 can be made of a conductive material having copper as a main component. The support portion 151 can also be combined with an insulating member such as a metal plate independent of the lead frame 150, a plate made of a semiconductor, or a chip bonding film.

[0172] 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 direction intersecting the thickness direction may be a direction along a plane (XY plane) orthogonal to the thickness direction. 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.

[0173] like Fig. 13B As shown, a pair of terminals 142a, 142b and a plurality of terminals 152a may protrude outward from different heights in the thickness direction of the sealing portion 130 of the side surfaces 130a and 130b of the sealing portion 130 that are opposite to each other. The surfaces 1521 of the plurality of terminals 152a on the same side as the first surface 100a of the signal processing IC 100 may be located at the same height as the surfaces 1421 of the pair of terminals 142a, 142b on the same side as the surfaces on the opposite side to the first surface 100a of the signal processing IC 100 in the thickness direction (Z-axis direction) of the sealing portion 130. Alternatively, the surfaces 1521 of the plurality of terminals 152a may be located below the surfaces 1421 of the pair of terminals 142a, 142b in the thickness direction of the sealing portion 130.

[0174] That is, the height of the surface 1521 of the plurality of terminals 152a at the position intersecting the side surface 130a of the sealing portion 130 on the same side as the surface 100a of the signal processing IC 100 in the thickness direction (Z-axis direction) of the sealing portion 130 may be the same as the height of the surface 1421 of the pair of terminals 142a, 142b at the position intersecting the side surface 130b of the sealing portion 130 on the same side as the surface on the opposite side to the surface 100a of the signal processing IC 100 in the thickness direction (Z-axis direction) of the sealing portion 130. Alternatively, the height of the surface 1521 of the plurality of terminals 152a at the position intersecting the side surface 130a 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 intersecting the side surface 130b of the sealing portion 130 in the thickness direction (Z-axis direction) of the sealing portion 130.

[0175] When lead frame 140 and lead frame 150 are overlapped in the thickness direction, in order to ensure insulation between lead frame 140 and lead frame 150 or signal processing IC 100 , a step needs to be provided in at least one of lead frame 140 and lead frame 150 in the thickness direction.

[0176] The conductor portion 141 is bent in the sealing portion 130 so as to approach the second surface 130f on the second surface 151b side of the support portion 151 in the sealing portion 130 and is connected to the terminal portion 142. The conductor portion 141 may be bent so as to be connected to the terminal portion 142 so as to approach the second surface 130f on the second surface 151b side of the support portion 151 in the sealing portion 130 by more than half the thickness of the conductor portion 141 compared to the surface of the second surface 141b of the conductor portion 141 facing the first surface 100a which is the circuit surface of the signal processing IC 100 and be connected to the terminal portion 142. That is, the height difference between the surface of the second surface 141b of the conductor portion 141 facing the first surface 100a which is the circuit surface of the signal processing IC 100 and the portion of the second surface 141b of the conductor portion 141 connected to the terminal portion 142 may be more than half the thickness of the conductor portion 141. The conductor portion 141 may be bent in the sealing portion 130 so as to approach the second surface 130f on the second surface 151b side of the support portion 151 in the sealing portion 130 and connected to the terminal portion 142. The conductor portion 141 may be bent by a bending process.

[0177] Fig.14A and Fig. 14B This is an example of the current sensor 10 in which a magneto-electric conversion element is arranged at a position for detecting a magnetic field in the X-axis direction. Fig.14A Indicate as Fig.13AThe internal structure of a semiconductor package in which the current sensor 10 according to the modification of the embodiment shown in the figure functions. Fig.14A yes Fig.13A The illustrated embodiment is a schematic plan view of a current sensor 10 according to a modified example of the embodiment, as viewed from the top surface side (Z-axis direction). Fig. 14B yes Fig.14A The AA line cross-sectional view of the current sensor 10 is shown. Fig.13A In the current sensor 10 according to the modified example of the embodiment shown, the magneto-electric conversion elements 20 a and 20 b are built in a chip constituting the signal processing IC 100 .

[0178] In the fifth embodiment, an example in which the current sensor 10 includes two magneto-electric transducers 20a and 20b is described. However, the current sensor 10 only needs to include at least one magneto-electric transducer.

[0179] The sealing unit 130 seals the magnetoelectric conversion elements 20a and 20b, the conductor 141, the support 151, the signal processing IC 100, the wires 22 and 108 with a mold resin. The mold resin is composed of, for example, a thermosetting epoxy resin containing silicon dioxide, and can be formed into a semiconductor package by transfer molding.

[0180] Fig.15 express Fig. 13B An example of an enlarged view of the enclosed portion indicated by reference numeral 300 is shown in the figure. The conductor portion 141 has: a first corner portion 1401 located between a first end surface 141c on the opposite side to the side connected to the terminal portion 142 and a surface 141b facing the signal processing IC 100; and a second corner portion 1402 located between the first end surface 141c and a first surface 141a on the opposite side to the second surface 141b facing the first surface 100a of the signal processing IC 100.

[0181] The second corner 1402 is a chamfered surface. The area of ​​the outer surface of the second corner 1402 is larger than the area of ​​the outer surface of the first corner 1401. The area of ​​the outer surface of the first corner 1401 is the area of ​​the outer surface defined from the boundary between the second surface 141b and the first corner 1401 to the boundary between the first end surface 141c and the first corner 1401. The area of ​​the outer surface of the second corner 1402 is the area of ​​the outer surface defined from the boundary between the first end surface 141c and the second corner 1402 to the boundary between the first surface 141a and the second corner 1402. The first corner 1401 may be a substantially straight line along the X-axis direction. The area of ​​the outer surface of the first corner 1401 may be substantially zero.

[0182] By chamfering the second corner portion 1402 in this manner, it is possible to suppress the concentration of thermal stress near the corner portion, suppress the occurrence of cracks in the sealing portion 130 , and improve the durability of the current sensor 10 .

[0183] The chamfered shape of the second corner portion 1402 may be any shape, or may be composed of a plurality of surfaces formed by combining a plurality of substantially flat surfaces. Fig.16A As shown, it can be composed of a substantially flat surface, or it can be composed of a substantially flat surface. Fig. 16B As shown in the figure, it is composed of one side of the R surface (curved surface), and it can also be Fig. 16C As shown, it is composed of two surfaces formed by combining two roughly flat surfaces. Fig. 16B As shown, when the second corner 1402 is an R surface, the area of ​​the outer surface of the second corner 1402 is the area of ​​the curved surface portion. The boundary between the first end surface 141c and the second corner 1402 and the boundary between the first surface 141a and the second corner 1402 are the starting points of the curved surface.

[0184] The reason why the concentration of thermal stress near the corner portion can be suppressed by chamfering the second corner portion 1402 will be described below.

[0185] Here, in the durability test of the current sensor 10, there is a test in which the state of the current sensor 10 is measured in an environment of a predetermined minimum temperature, for example, -65 degrees. In such an environment, the linear expansion coefficient of the lead frame 140 is larger than the linear expansion coefficient of the molding resin constituting the sealing portion 130. Therefore, a force is applied to the lead frame 140 in a direction in which the lead frame 140 contracts more than the sealing portion 130. Therefore, the contraction speed of the sealing portion 130 cannot keep up with the contraction speed of the lead frame 140, and the sealing portion 130 is stretched by the lead frame 140. As a result, cracks may be generated in the sealing portion 130.

[0186] In the case of a structure in which the lead frame 140 and the lead frame 150 overlap in the thickness direction, the distance between the top surface (surface 130e) of the sealing portion 130 and the lead frame 140 is relatively short. That is, the molded resin between the top surface of the sealing portion 130 and the lead frame 140 becomes thinner. Alternatively, the distance between the bottom surface (surface 130f) of the sealing portion 130 and the lead frame 150 is relatively short. That is, the molded resin between the bottom surface of the sealing portion 130 and the lead frame 150 becomes thinner. Therefore, cracks may occur between the top surface (surface 130e) of the sealing portion 130 and the lead frame 140, or between the bottom surface (surface 130f) of the sealing portion 130 and the lead frame 150.

[0187] In the case of a structure in which the lead frame 140 and the lead frame 150 overlap in the thickness direction, the step generated by the bending process in the sealing portion is preferably at least half of the thickness of the lead frame 140 or the lead frame 150. As a result, the accuracy of the bending process is improved. In addition, there is no need to perform a bending process for providing a step in the support portion 151 of the lead frame 150. However, the distance between the surface of the sealing portion 130 and the lead frame 140 or the lead frame 150 is likely to be shortened.

[0188] exist Fig. 13B and Fig. 13C In the embodiment, the conductor part 141 has a step generated by the bending process in the sealing part 130. That is, the conductor part 141 has a flat part 143, a step part 144 and a flat part 145 that are physically connected. In addition, in the conductor part 141, the flat part 143 is the part closest to the top surface of the seal. Here, as Fig. 13B and Fig. 13C As shown, when the distance between the first surface 130e on the first surface 141a side of the conductor part 141 in the sealing part 130 and the first surface 141a of the conductor part 141 is t1, the width of the flat part 143 in the X-axis direction intersecting the Y-axis direction along the first surface 141a of the conductor part 141 is l1, the distance between the second surface 141b of the conductor part 141 and the first surface 100a of the signal processing IC 100 is t2, and the portion of the width of the flat part 143 in the X-axis direction along the first surface 100a of the signal processing IC 100 that faces the second surface 141b is l2, l1 / t1>l2 / t2 is satisfied. Alternatively, in this case, the aspect ratio of the molding resin with a thickness of t1 is greater than the aspect ratio of the molding resin with a thickness of t2, and the stress of the first corner 1401 of the surface closest to the sealing part 130 in the interface between the lead frame 140 and the sealing part 130 subjected to the bending process in the sealing part 130 is the largest.

[0189] In the flat portion 143, the length in the Y-axis direction along the first surface 141a of the conductor portion 141 is set to l1, and the portion of the flat portion 143 opposite to the second surface 141b in the width in the Y-axis direction along the first surface 100a of the signal processing IC 100 is set to l2. When l1 / t1>l2 / t2 is satisfied, in the sealing portion 130, the stress of the first corner portion 1401 of the surface closest to the sealing portion 130 in the interface between the lead frame 140 and the sealing portion 130 subjected to bending processing is the largest.

[0190] Fig.17A An example of simulation results of thermal stress when the current sensor 10 is placed in an environment of -65 degrees, the minimum temperature required in a durability test, in a structure where the second corner portion 1402 is not chamfered is shown. Fig. 17BAn example of simulation results of thermal stress when the current sensor 10 is placed in an environment of -65 degrees, the minimum temperature required in a durability test, in a structure in which the second corner portion 1402 is chamfered is shown. Fig.17A and Fig. 17B Curve showing the contours of thermal stress. Fig.17A and Fig. 17B It can be seen that near the second corner 1402, Fig.17A The contour ratio of thermal stress shown Fig. 17B That is, it can be seen that when chamfering is not performed, thermal stress is likely to concentrate near the second corner 1402.

[0191] In the case of a structure in which the lead frame 140 on the current conductor side and the lead frame 150 on the signal terminal side overlap in the thickness direction, the location where thermal stress is most likely to be concentrated is the second corner 1402 of the tip portion of the sealing portion 130 in the conductor portion 141 of the lead frame 140 on the current conductor side. Therefore, by chamfering the second corner 1402, the concentration of thermal stress can be suppressed, and the durability of the current sensor 10 can be improved.

[0192] The molded resin constituting the sealing portion 130 contains a large amount of filler. The molded resin contains filler having a filler diameter (diameter) of 20 μm or more, and the filling rate of the filler is 60% or more. The mode of the diameter of the filler contained in the molded resin is about 20 μm. Furthermore, in the case of a three-dimensional sphere having a diameter of about 20 μm, when observed on the line segment of the chamfered portion, the dimension is reduced to one dimension, so the filler diameter is 15 μm (20 μm×(√3 / 2) 2 )about.

[0193] Here, in the case where a tiny crack is generated from a position with considerable stress, it is important to improve the toughness of the position in order to suppress the progress of the crack. In the case where the interface between the filler and the base material in the molded resin peels off, since the energy of the peeling is high, by including the filler, the toughness can be improved for the cracking of the base material such as epoxy resin, which is a fragile material. Therefore, it is preferred that the interface between the filler and the base material exists in the chamfered area where stress is concentrated. That is, when the filler exists on the surface of the conductor part 141, it is difficult for the filler to peel off from the surface of the conductor part 141, and it is difficult for cracks to occur in the sealing part 130. Therefore, if the width of the chamfered surface is greater than the filler diameter, the possibility of the filler existing in the chamfered part becomes very high, and it is difficult for cracks to occur in the sealing part 130.

[0194] As described above, the molding resin constituting the sealing portion 130 contains a filler having a filler diameter (diameter) of 20 μm or more, and the filling rate of the filler is 60% or more. When observed on the line segment of the chamfered portion, the dimension is reduced to one dimension, so the filler diameter is about 15 μm. If the filling rate of the filler is considered to be 60% or more, then when the surface is greater than 15 μm × 0.4 / 0.6 = 10 μm, there is an interface between the filler and the base material in the chamfered area with a probability of more than 60%. Therefore, it is preferred that the length of the edge of the chamfered surface is greater than 10 μm, and it is preferred to ensure that the one-dimensional filler diameter is greater than 15 μm.

[0195] Fig.16A , Fig. 16B and Fig. 16C An example of the chamfered shape of the second corner 1402 is shown. The width of the first direction Y axis when the second corner 1402 is projected in the Z axis direction is set to width w1, and the width of the second corner 1402 in the Z axis direction along the first end surface 1412c when the second corner 1402 is projected in the Y axis direction along the first surface 141a of the conductor part 141 is set to width w2. In this case, either the width w1 or the width w2 is greater than 15μm and shorter than the thickness of the conductor part 141. As a result, as described above, the possibility of the presence of filler in the chamfered portion can be increased. As a result, the initial development of the crack can be suppressed, and the reliability of the current sensor 10 can be improved.

[0196] According to the current sensor 10 of the fifth embodiment, the interface between the filler and the base material can be easily present near the corner where the thermal stress concentrates, and the initial progress of the crack can be suppressed, thereby improving the reliability of the current sensor 10.

[0197] In the above-mentioned embodiment, the description is given of a mode in which the lead frame 140 is bent. However, the lead frame 150 may be bent instead of the lead frame 140 .

[0198] Fig.18A It is a cross-sectional view of the current sensor 10 as viewed from the X-axis direction. Fig.18B It is a cross-sectional view of the current sensor 10 as viewed from the Y-axis direction.

[0199] The current sensor 10 of the sixth embodiment is different from the current sensor 10 of the fifth embodiment in that a lead frame 150 is bent instead of the lead frame 140 , and a fourth corner 1504 of a support portion 151 is chamfered instead of a second corner 1401 of a conductor portion 141 .

[0200] The support portion 151 is bent so as to approach the first surface 130e on the first surface 141a side of the conductor portion 141 in the sealing portion 130 and is connected to the terminal portion 152. The support portion 151 may be bent so as to be connected to the terminal portion 152 so as to approach the first surface 130e on the first surface 141a side of the conductor portion 141 in the sealing portion 130 by more than half the thickness of the support portion 151 compared to the surface of the first surface 151a of the support portion 151 supporting the signal processing IC 100.

[0201] The pair of terminals 142a and 142b protrude from the side surface 130a toward the negative side in the Y-axis direction and bend toward the negative side in the Z-axis direction. The plurality of terminals 152a protrude from the side surface 130b toward the positive side in the Y-axis direction and bend toward the negative side in the Z-axis direction.

[0202] When the measured current flows through the lead frame 140, heat corresponding to the resistance is generated, so it is preferable to increase the thickness of the plate to reduce the resistance. On the other hand, when the lead frame is bent, a step of any size can be formed regardless of the thickness of the plate. Therefore, even if a thin lead frame is used for the lead frame 150 in order to reduce the material used, a desired step can be formed. As a result, the lead frame 150 can be thinner than the lead frame 140.

[0203] As described above, in the case of a structure in which the lead frame 140 and the lead frame 150 overlap in the thickness direction, the distance between the bottom surface (surface 130f) of the sealing portion 130 and the lead frame 150 is relatively short. That is, the molded resin between the bottom surface of the sealing portion 130 and the lead frame 150 becomes thinner. Therefore, there is a possibility that cracks will occur between the bottom surface of the sealing portion 130 and the lead frame 150.

[0204] In the case of a structure in which the lead frame 140 and the lead frame 150 overlap in the thickness direction, the step generated by the bending process is preferably at least half of the thickness of the lead frame 140 or the lead frame 150. Thus, the accuracy of the bending process is improved. In addition, there is no need to perform a bending process for providing a step on the conductor portion 141 of the lead frame 140. However, the distance between the surface of the sealing portion 130 and the lead frame 150 is likely to be shortened.

[0205] exist Fig. 6A and Figure 6B In the embodiment, the support portion 151 has a step generated by bending in the sealing portion 130. That is, the support portion 151 has a flat portion 153, a step portion 154, and a flat portion 155 that are physically connected. In addition, in the support portion 151, the flat portion 153 is the portion closest to the bottom surface of the seal. Here, as Fig.18A and Fig.18BAs shown, when the distance between the second surface 130f on the second surface 151b side of the support portion 151 in the sealing portion 130 and the second surface 151b of the support portion 151 is t3, the width along the second surface 151b of the support portion 151 in the X-axis direction is l3, the distance between the second surface 141b of the conductor portion 141 and the first surface 100a of the signal processing IC 100 is t2, and the width of the portion of the width along the X-axis direction of the first surface 100a of the signal processing IC 100 that faces the second surface 141b of the conductor portion 141 is l2, l3 / t3>l2 / t2 is satisfied. In this case, the aspect ratio of the molding resin with a thickness of t3 is greater than the aspect ratio of the molding resin with a thickness of t2, and the stress of the fourth corner 1504 of the surface closest to the sealing portion 130 in the interface between the lead frame 150 and the sealing portion 130 subjected to the bending process in the sealing portion 130 is the largest.

[0206] In the flat portion 153, the length in the Y-axis direction along the second surface 151b of the supporting portion 151 is set to l1, and the portion of the width in the Y-axis direction along the first surface 100a of the signal processing IC100 that is opposite to the second surface 141b of the conductor portion 141 is set to l2. When l1 / t1>l2 / t2 is satisfied, in the sealing portion 130, the stress of the first corner 1401 of the surface closest to the sealing portion 130 in the interface between the lead frame 140 and the sealing portion 130 subjected to bending processing is the largest.

[0207] Fig.19 express Fig.18A An example of an enlarged view of the enclosed portion indicated by reference numeral 400 is shown in the figure. The support portion 151 has: a third corner portion 1503 located between a second end surface 151c on the opposite side to the side connected to the terminal portion 152 and a first surface 151a of the support portion 151 supporting the signal processing IC 100; and a fourth corner portion 1504 located between the second end surface 151c and a second surface 151b on the opposite side to the first surface 151a of the support portion 151.

[0208] The area of ​​the outer surface of the third corner portion 1503 is the area of ​​the outer surface defined from the boundary between the third face 151a and the third corner portion 1503 to the boundary between the second end face 151c and the third corner portion 1503. The area of ​​the outer surface of the fourth corner portion 1504 is the area of ​​the outer surface defined from the boundary between the second end face 151c and the fourth corner portion 1504 to the boundary between the second face 151b and the fourth corner portion 1504. The area of ​​the outer surface of the third corner portion 1503 may be substantially zero.

[0209] As described above, the stress of the fourth corner 1504 closest to the surface of the sealing portion 130 is the largest. Therefore, the fourth corner 1504 is chamfered. That is, the area of ​​the outer surface of the fourth corner 1504 is larger than the area of ​​the outer surface of the third corner 1503. In this way, by chamfering the fourth corner 1504, the concentration of thermal stress near the corner portion can be suppressed, the generation of cracks in the sealing portion 130 can be suppressed, and the durability of the current sensor 10 can be improved.

[0210] Fig. 20 An example of the chamfered shape of the fourth corner 1504 is shown. The width of the fourth corner 1504 in the direction along the second surface 151b of the support portion 151 when projected in the Z-axis direction along the second end surface 151c is set to w3, and the width of the fourth corner 1504 in the Z-axis direction along the second end surface 151c when projected in the Y-axis direction along the second surface 151b of the support portion 151 is set to w4. In this case, either the width w3 or the width w4 is greater than 15μm and shorter than the thickness of the support portion 151. As a result, as described above, the possibility of the presence of filler in the chamfered portion can be increased. As a result, the initial development of the crack can be suppressed, and the reliability of the current sensor 10 can be improved.

[0211] 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. According to the description of the claims, the method to which such changes or improvements are made is also included in the technical scope of the present invention.

[0212] It should be noted that the execution order of each process such as actions, steps, steps and stages in the device, system, program and method shown in the claims, specifications and drawings can be implemented in any order unless it is specifically stated as "before", "before", etc., and as long as 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.

[0213] (Other possible projects)

[0214] (Item 1)

[0215] An electromagnetic conversion device, comprising:

[0216] at least one magnetoelectric conversion element;

[0217] a first lead frame including a first terminal portion and a conductor portion connected to the first terminal portion, and a measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion;

[0218] a signal processing IC disposed on a second surface side opposite to the first surface of the conductor portion, having a circuit surface on which the at least one magnetoelectric conversion element is disposed and opposite to the second surface, and processing a signal output from the at least one magnetoelectric conversion element; and

[0219] a sealing portion, sealing the at least one magnetoelectric conversion element, the conductor portion and the signal processing IC,

[0220] The conductor portion has a first corner portion and a second corner portion, the first corner portion is located between a first end surface on the opposite side to the side connected to the first terminal portion and a second surface opposite to the signal processing IC, and the second corner portion is located between the first end surface and a first surface on the opposite side to the second surface opposite to the signal processing IC.

[0221] An area of ​​an outer surface of the first corner portion is larger than an area of ​​an outer surface of the second corner portion.

[0222] (Item 2)

[0223] The current sensor according to item 1, wherein:

[0224] The first corner portion is a chamfered surface.

[0225] (Item 3)

[0226] The current sensor according to item 1, wherein:

[0227] Either a width of the first corner portion in a direction along the second surface of the conductor portion when projected in a direction along the first end surface or a width of the first corner portion in a direction along the first end surface when projected in a direction along the second surface of the conductor portion is greater than 15 μm and shorter than a thickness of the conductor portion.

[0228] (Item 4)

[0229] The current sensor according to item 1, wherein:

[0230] A width of the first corner portion in a direction along the second surface of the conductor portion when projected in a direction along the first end surface is longer than a width of the first corner portion in a direction along the first end surface when projected in a direction along the second surface of the conductor portion.

[0231] (Item 5)

[0232] The current sensor according to item 1, wherein:

[0233] The conductor portion has:

[0234] A first portion connected to the first terminal portion; and

[0235] The second portion is arranged opposite to the circuit surface of the signal processing IC, is offset relative to the first portion in a direction away from the circuit surface of the signal processing IC in a thickness direction, and is connected to the first portion.

[0236] The second portion has a third corner portion, and the third corner portion is located between a second end surface on the side connected to the first portion and a first surface on the opposite side of the second surface facing the circuit surface of the signal processing IC.

[0237] An outer surface area of ​​the third corner portion is larger than an outer surface area of ​​a fourth corner portion located between the second end surface of the second portion and a first surface of the first portion on the same side as the first surface of the second portion.

[0238] (Item 6)

[0239] The current sensor according to item 5, wherein:

[0240] The third corner portion is a chamfered surface.

[0241] (Item 7)

[0242] The current sensor according to item 5, wherein:

[0243] Either a width of the third corner in a direction along the first surface opposite to the second surface of the conductor portion when projected in a direction along the second end surface, or a width of the third corner in a direction along the second end surface when projected in a direction along the first surface of the conductor portion is greater than 15 μm and shorter than the thickness of the conductor portion.

[0244] (Item 8)

[0245] The current sensor according to item 5, wherein:

[0246] An offset amount of the second portion relative to the first portion is equal to or less than 0.6 times the thickness of the conductor portion.

[0247] (Item 9)

[0248] The current sensor according to item 5, wherein:

[0249] The second end surface of the second portion has a shear surface.

[0250] (Item 10)

[0251] The current sensor according to item 5, wherein:

[0252] The current sensor further includes a second lead frame, the second lead frame includes a second terminal portion and a support portion, and is electrically insulated from the first lead frame, the second terminal portion is arranged opposite to the first terminal portion across the signal processing IC when viewed from above and is electrically connected to the signal processing IC, and the support portion supports a surface of the signal processing IC on the opposite side of the circuit surface on the conductor portion side with a first surface,

[0253] The first portion has a fifth corner portion, and the fifth corner portion is located between a third end surface on one side connected to the second portion and a second surface on the same side as the second surface of the second portion.

[0254] An outer surface area of ​​the fifth corner portion is larger than an outer surface area of ​​a sixth corner portion, and the sixth corner portion is located between the third end surface of the first portion and the second surface of the second portion.

[0255] (Item 11)

[0256] The current sensor according to item 10, wherein:

[0257] The fifth corner is a chamfered surface.

[0258] (Item 12)

[0259] The current sensor according to item 10, wherein:

[0260] Either a width of the fifth corner portion in a direction along the second surface of the first portion when projected in a direction along the third end surface, or a width of the fifth corner portion in a direction along the third end surface when projected in a direction along the second surface of the first portion is greater than 15 μm and shorter than the thickness of the conductor portion.

[0261] (Item 13)

[0262] The current sensor according to item 10, wherein:

[0263] The support portion has a seventh corner and an eighth corner, the seventh corner is located between the first surface supporting the signal processing IC and the fourth end surface on the first terminal portion side, and the eighth corner is located between the second surface on the opposite side of the first surface supporting the signal processing IC and the fourth end surface,

[0264] An area of ​​an outer surface of the seventh corner portion is larger than an area of ​​an outer surface of the eighth corner portion.

[0265] (Item 14)

[0266] A current sensor according to any one of items 3, 7 and 11, wherein:

[0267] The sealing portion is formed of a mold resin, the mold resin contains a filler having a diameter of 20 μm or more, and the filling rate of the filler is 60% or more.

[0268] (Item 15)

[0269] The current sensor according to item 1, wherein:

[0270] The at least one magneto-electric transducer element protrudes from the circuit surface to a position overlapping with the conductor portion when viewed from a direction intersecting with a thickness direction of the at least one magneto-electric transducer element.

[0271] (Item 16)

[0272] The current sensor according to item 1, wherein:

[0273] The at least one magneto-electric conversion element is formed of a chip different from a chip forming the signal processing IC.

[0274] (Item 17)

[0275] The current sensor according to item 1, wherein:

[0276] The at least one magneto-electric conversion element is built into a chip constituting the signal processing IC.

[0277] (Item 18)

[0278] The current sensor according to item 1, wherein:

[0279] The conductor portion has at least one slit portion,

[0280] The at least one magneto-electric conversion element is respectively arranged in the at least one slit portion in a plan view so as to be at least partially surrounded by the conductor portion.

[0281] (Item 19)

[0282] The current sensor according to item 18, wherein:

[0283] The at least one magneto-electric conversion element is fixed to the circuit surface by die bonding in the at least one slit portion when viewed from above, and is electrically connected to the signal processing IC by wire bonding.

[0284] (Item 20)

[0285] The current sensor according to item 19, wherein:

[0286] When viewed from a direction intersecting the thickness direction of the at least one magneto-electric transducer element, the magneto-sensitive surface of the at least one magneto-electric transducer element is arranged at a position overlapping with the side surface of the conductor portion provided with the at least one slit.

[0287] (Item 21)

[0288] The current sensor according to item 1, wherein:

[0289] The at least one magneto-electric conversion element is a Hall element that detects a longitudinal magnetic field in a thickness direction of the conductor portion.

[0290] (Item 22)

[0291] The current sensor according to item 1, wherein:

[0292] The at least one magneto-electric conversion element is a magnetoresistive element that detects a transverse magnetic field in a direction along the second surface of the conductor portion.

[0293] (Item 23)

[0294] An electromagnetic conversion device, comprising:

[0295] at least one magnetoelectric conversion element;

[0296] a first lead frame including a first terminal portion and a conductor portion connected to the first terminal portion, and a measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion;

[0297] a signal processing IC disposed on a second surface side opposite to the first surface of the conductor portion, having a circuit surface on which the at least one magnetoelectric conversion element is disposed and opposite to the second surface, and processing a signal output from the at least one magnetoelectric conversion element; and

[0298] a sealing portion, sealing the at least one magnetoelectric conversion element, the conductor portion and the signal processing IC,

[0299] The conductor portion has:

[0300] A first portion connected to the first terminal portion; and

[0301] The second portion is arranged opposite to the circuit surface of the signal processing IC, is offset relative to the first portion in a direction away from the circuit surface of the signal processing IC in a thickness direction, and is connected to the first portion.

[0302] The second portion has a third corner portion, and the third corner portion is located between a second end surface on the side connected to the first portion and a first surface on the opposite side of the second surface facing the circuit surface of the signal processing IC.

[0303] An outer surface area of ​​the third corner portion is larger than an outer surface area of ​​a fourth corner portion, and the fourth corner portion is located between the second end surface of the second portion and a first surface of the first portion on the same side as the first surface of the second portion.

[0304] (Item 24)

[0305] The current sensor according to item 23, wherein:

[0306] The second end surface of the second portion has a shear surface.

[0307] (Item 25)

[0308] A current sensor comprising:

[0309] at least one magnetoelectric conversion element;

[0310] a first lead frame including a first terminal portion and a conductor portion connected to the first terminal portion, and a measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion;

[0311] a signal processing IC having a circuit surface on which the at least one magnetoelectric conversion element is disposed, and processing a signal output from the at least one magnetoelectric conversion element;

[0312] a second lead frame including a second terminal portion and a support portion, and being electrically insulated from the first lead frame, wherein the second terminal portion is arranged opposite to the first terminal portion with the signal processing IC interposed therebetween in a plan view and is electrically connected to the signal processing IC, and the support portion supports the signal processing IC with a first surface; and

[0313] a sealing portion that seals the at least one magnetoelectric conversion element, the conductor portion, the signal processing IC, and the support portion,

[0314] The conductor portion has a first shear surface, which is located closer to the first terminal portion than the signal processing IC when viewed from above, faces the second terminal portion, and is a step or end surface having the shear surface. The area of ​​the outer surface of the fifth corner among the corners of the first shear surface is larger than the area of ​​the outer surface of the sixth corner. The fifth corner is located on the side of the second surface opposite to the first surface of the support portion, and the sixth corner is located on the side away from the second surface.

[0315] (Item 26)

[0316] A current sensor comprising:

[0317] at least one magnetoelectric conversion element;

[0318] a first lead frame including a first terminal portion and a conductor portion connected to the first terminal portion, and a measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion;

[0319] a signal processing IC having a circuit surface on which the at least one magnetoelectric conversion element is disposed, and processing a signal output from the at least one magnetoelectric conversion element;

[0320] a second lead frame including a second terminal portion and a support portion, and being electrically insulated from the first lead frame, wherein the second terminal portion is arranged opposite to the first terminal portion with the signal processing IC interposed therebetween in a plan view and is electrically connected to the signal processing IC, and the support portion supports the signal processing IC with a first surface; and

[0321] a sealing portion that seals the at least one magnetoelectric conversion element, the conductor portion, the signal processing IC, and the support portion,

[0322] The support portion has a seventh corner and an eighth corner, the seventh corner is located between the first surface supporting the signal processing IC and the second end surface on the first terminal portion side, and the eighth corner is located between the second surface on the opposite side of the first surface supporting the signal processing IC and the second end surface,

[0323] An area of ​​an outer surface of the seventh corner portion is larger than an area of ​​an outer surface of the eighth corner portion.

[0324] (Other possible projects)

[0325] (Item 1)

[0326] A current sensor comprising:

[0327] at least one magnetoelectric converter;

[0328] A first lead frame including a first terminal portion and a conductor portion connected to the first terminal portion, and a measurement current measured by the at least one magnetoelectric converter portion flows through the first terminal portion and the conductor portion;

[0329] a signal processing unit, arranged on a second surface side opposite to the first surface of the conductor unit, having a circuit surface opposite to the second surface of the conductor unit, on which the at least one magnetoelectric converter is arranged, and processing a signal output from the at least one magnetoelectric converter;

[0330] A second lead frame including a support portion and a second terminal portion, wherein the support portion supports a support surface on the opposite side of the circuit surface of the signal processing portion with a first surface, and the second terminal portion is connected to the support portion and outputs a signal from the signal processing portion; and

[0331] a sealing portion, sealing the at least one magnetoelectric conversion portion, the conductor portion, the signal processing portion and the support portion,

[0332] The conductor portion has: a first corner portion located between a first end surface on the opposite side to the side connected to the first terminal portion and a second surface opposite to the signal processing portion; and a second corner portion located between the first end surface and the first surface of the conductor portion,

[0333] The support portion includes: a third corner portion located between a second end surface on the opposite side to the side connected to the second terminal portion and the first surface of the support portion supporting the signal processing portion; and a fourth corner portion located between the second end surface and the second surface on the opposite side to the first surface of the support portion,

[0334] The area of ​​the outer surface of the second corner portion is larger than the area of ​​the outer surface of the first corner portion, or the area of ​​the outer surface of the fourth corner portion is larger than the area of ​​the outer surface of the third corner portion.

[0335] (Item 2)

[0336] The current sensor according to item 1, wherein:

[0337] The outer surface area of ​​the second corner portion is larger than that of the first corner portion, and the conductor portion is bent so as to approach the second surface of the sealing portion on the second surface side of the support portion to be connected to the first terminal portion.

[0338] (Item 3)

[0339] The current sensor according to item 1, wherein:

[0340] The area of ​​the outer surface of the second corner portion is larger than the area of ​​the outer surface of the first corner portion, and the conductor portion is bent and connected to the first terminal portion in a manner that is closer to the second surface on the second surface side of the supporting portion in the sealing portion than the surface of the second surface of the conductor portion opposite to the circuit surface of the signal processing portion, and the surface of the second surface of the conductor portion connected to the first terminal portion is more than half the thickness of the conductor portion.

[0341] (Item 4)

[0342] The current sensor according to item 1, wherein:

[0343] The outer surface area of ​​the fourth corner portion is larger than that of the third corner portion, and the support portion is bent so as to approach the first surface of the conductor portion in the sealing portion and connected to the second terminal portion.

[0344] (Item 5)

[0345] The current sensor according to item 1, wherein:

[0346] The area of ​​the outer surface of the fourth corner portion is larger than the area of ​​the third corner portion, and the support portion is bent and connected to the second terminal portion in a manner that the surface of the first surface of the support portion that supports the signal processing portion is closer to the first surface on the first surface side of the conductor portion in the sealing portion by more than half the thickness of the support portion.

[0347] (Item 6)

[0348] The current sensor according to item 1, wherein:

[0349] The area of ​​the outer surface of the second corner portion is larger than the area of ​​the outer surface of the first corner portion, and the second corner portion is a chamfered surface.

[0350] (Item 7)

[0351] The current sensor according to item 1, wherein:

[0352] The area of ​​the outer surface of the fourth corner portion is larger than the area of ​​the outer surface of the third corner portion, and the fourth corner portion is a chamfered surface.

[0353] (Item 8)

[0354] The current sensor according to item 1, wherein:

[0355] At a predetermined minimum temperature, a linear expansion coefficient of the first lead frame or the second lead frame is larger than a linear expansion coefficient of a mold resin constituting the sealing portion.

[0356] (Item 9)

[0357] The current sensor according to item 1, wherein:

[0358] When the area of ​​the outer surface of the second corner is larger than the area of ​​the outer surface of the first corner, either the width of the second corner in the direction along the first surface of the conductor part when projected in the direction along the first end surface, or the width of the second corner in the direction along the first end surface when projected in the direction along the first surface of the conductor part is greater than 15 μm and shorter than the thickness of the conductor part.

[0359] (Item 10)

[0360] The current sensor according to item 9, wherein:

[0361] The sealing portion is formed of a mold resin, the mold resin contains a filler having a diameter of 20 μm or more, and the filling rate of the filler is 60% or more.

[0362] (Item 11)

[0363] The current sensor according to item 1, wherein:

[0364] The area of ​​the outer surface of the fourth corner is larger than the area of ​​the outer surface of the third corner, and either the width of the fourth corner in the direction along the second surface of the support portion when projected in the direction along the second end surface, or the width of the fourth corner in the direction along the second end surface when projected in the direction along the second surface of the support portion is larger than 15 μm and shorter than the thickness of the support portion.

[0365] (Item 12)

[0366] The current sensor according to item 11, wherein:

[0367] The sealing portion is formed of a mold resin, the mold resin contains a filler having a diameter of 20 μm or more, and the filling rate of the filler is 60% or more.

[0368] (Item 13)

[0369] The current sensor according to item 1, wherein:

[0370] The conductor portion is covered with the mold resin constituting the sealing portion and has no interface with anything other than the mold resin.

[0371] (Item 14)

[0372] The current sensor according to item 1, wherein:

[0373] The first lead frame is thicker than the second lead frame.

[0374] (Item 15)

[0375] The current sensor according to item 1, wherein:

[0376] The first terminal portion protrudes from a first side surface of the sealing portion, and the second terminal portion protrudes from a second side surface of the sealing portion that is opposite to the first side surface in a first direction.

[0377] The area of ​​the outer surface of the second corner portion is larger than the area of ​​the outer surface of the first corner portion,

[0378] When the distance between the first surface of the conductor part in the sealing part and the first surface of the conductor part is set to t1, the width of the portion of the conductor part opposite to the signal processing part in the second direction intersecting the first direction along the first surface of the conductor part is set to l1, the distance between the second surface of the conductor part and the circuit surface of the signal processing part is set to t2, and the width in the second direction along the circuit surface of the signal processing part is set to l2, l1 / t1>l2 / t2 is satisfied.

[0379] (Item 16)

[0380] The current sensor according to item 1, wherein:

[0381] The first terminal portion protrudes from a first side surface of the sealing portion, and the second terminal portion protrudes from a second side surface of the sealing portion opposite to the first side surface in a first direction.

[0382] The outer surface area of ​​the fourth corner portion is larger than the outer surface area of ​​the third corner portion,

[0383] When the distance between the second surface on the second surface side of the supporting part in the sealing part and the second surface of the supporting part is set to t3, the width of the part of the supporting part supporting the signal processing part in the second direction intersecting the first direction along the second surface of the supporting part is set to l3, the distance between the second surface of the conductor part and the circuit surface of the signal processing part is set to t2, and the width in the second direction along the circuit surface of the signal processing part is set to l2, then l3 / t3>l2 / t2 is satisfied.

[0384] (Item 17)

[0385] A current sensor according to any one of items 1 to 16, wherein

[0386] The signal processing unit is an IC chip,

[0387] The at least one magnetoelectric conversion unit is a magnetoelectric conversion element independent of the IC chip,

[0388] The magneto-electric conversion element has a magneto-sensitive surface that protrudes from a surface of the IC chip that faces the conductor portion.

[0389] (Item 18)

[0390] A current sensor according to any one of items 1 to 16, wherein

[0391] The signal processing unit is an IC chip,

[0392] The magnetoelectric conversion unit is built into the IC chip.

[0393] The magneto-sensitive surface of the magneto-electric converter does not protrude from a surface of the IC chip that faces the conductor portion.

Claims

1. A current sensor comprising: at least one magnetoelectric conversion element; a first lead frame including a first terminal portion and a conductor portion connected to the first terminal portion, and a measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion; a signal processing IC disposed on a second surface side opposite to the first surface of the conductor portion, having a circuit surface on which the at least one magnetoelectric conversion element is disposed and opposite to the second surface, and processing a signal output from the at least one magnetoelectric conversion element; and a sealing portion, sealing the at least one magnetoelectric conversion element, the conductor portion and the signal processing IC, The conductor portion has a first corner portion and a second corner portion, the first corner portion is located between a first end surface on the opposite side to the side connected to the first terminal portion and a second surface opposite to the signal processing IC, and the second corner portion is located between the first end surface and a first surface on the opposite side to the second surface opposite to the signal processing IC. An area of ​​an outer surface of the first corner portion is larger than an area of ​​an outer surface of the second corner portion.

2. The current sensor according to claim 1, wherein: The first corner portion is a chamfered surface.

3. The current sensor according to claim 1, wherein: Either a width of the first corner portion in a direction along the second surface of the conductor portion when projected in a direction along the first end surface or a width of the first corner portion in a direction along the first end surface when projected in a direction along the second surface of the conductor portion is greater than 15 μm and shorter than a thickness of the conductor portion.

4. The current sensor according to claim 1, wherein: A width of the first corner portion in a direction along the second surface of the conductor portion when projected in a direction along the first end surface is longer than a width of the first corner portion in a direction along the first end surface when projected in a direction along the second surface of the conductor portion.

5. The current sensor according to claim 1, wherein: The conductor portion has: A first portion connected to the first terminal portion; and The second portion is arranged opposite to the circuit surface of the signal processing IC, is offset relative to the first portion in a direction away from the circuit surface of the signal processing IC in a thickness direction, and is connected to the first portion. The second portion has a third corner portion, and the third corner portion is located between a second end surface on the side connected to the first portion and a first surface on the opposite side of the second surface facing the circuit surface of the signal processing IC. An outer surface area of ​​the third corner portion is larger than an outer surface area of ​​a fourth corner portion located between the second end surface of the second portion and a first surface of the first portion on the same side as the first surface of the second portion.

6. The current sensor according to claim 5, wherein: The third corner portion is a chamfered surface.

7. The current sensor according to claim 5, wherein: Either a width of the third corner in a direction along the first surface opposite to the second surface of the conductor portion when projected in a direction along the second end surface, or a width of the third corner in a direction along the second end surface when projected in a direction along the first surface of the conductor portion is greater than 15 μm and shorter than the thickness of the conductor portion.

8. The current sensor according to claim 5, wherein: An offset amount of the second portion relative to the first portion is equal to or less than 0.6 times the thickness of the conductor portion.

9. The current sensor according to claim 5, wherein: The second end surface of the second portion has a shear surface.

10. The current sensor according to claim 5, wherein: The current sensor further includes a second lead frame, the second lead frame includes a second terminal portion and a support portion, and is electrically insulated from the first lead frame, the second terminal portion is arranged opposite to the first terminal portion across the signal processing IC when viewed from above and is electrically connected to the signal processing IC, and the support portion supports a surface of the signal processing IC on the opposite side of the circuit surface on the conductor portion side with a first surface, The first portion has a fifth corner portion, and the fifth corner portion is located between a third end surface on one side connected to the second portion and a second surface on the same side as the second surface of the second portion. An outer surface area of ​​the fifth corner portion is larger than an outer surface area of ​​a sixth corner portion, and the sixth corner portion is located between the third end surface of the first portion and the second surface of the second portion.

11. The current sensor according to claim 10, wherein: The fifth corner is a chamfered surface.

12. The current sensor according to claim 10, wherein: Either a width of the fifth corner portion in a direction along the second surface of the first portion when projected in a direction along the third end surface, or a width of the fifth corner portion in a direction along the third end surface when projected in a direction along the second surface of the first portion is greater than 15 μm and shorter than the thickness of the conductor portion.

13. The current sensor according to claim 10, wherein: The support portion has a seventh corner and an eighth corner, the seventh corner is located between the first surface supporting the signal processing IC and the fourth end surface on the first terminal portion side, and the eighth corner is located between the second surface on the opposite side of the first surface supporting the signal processing IC and the fourth end surface, An area of ​​an outer surface of the seventh corner portion is larger than an area of ​​an outer surface of the eighth corner portion.

14. The current sensor according to any one of claims 3, 7 and 11, wherein: The sealing portion is formed of a mold resin, the mold resin contains a filler having a diameter of 20 μm or more, and the filling rate of the filler is 60% or more.

15. The current sensor according to claim 1, wherein: When viewed from a direction intersecting a thickness direction of the at least one magneto-electric transducer element, the at least one magneto-electric transducer element protrudes from the circuit surface to a position overlapping with the conductor portion.

16. The current sensor according to claim 1, wherein: The at least one magneto-electric conversion element is formed of a chip different from a chip forming the signal processing IC.

17. The current sensor according to claim 1, wherein: The at least one magneto-electric conversion element is built into a chip constituting the signal processing IC.

18. The current sensor according to claim 1, wherein: The conductor portion has at least one slit portion, The at least one magneto-electric conversion element is respectively arranged in the at least one slit portion in a plan view so as to be at least partially surrounded by the conductor portion.

19. The current sensor according to claim 18, wherein: The at least one magneto-electric conversion element is fixed to the circuit surface by die bonding in the at least one slit portion when viewed from above, and is electrically connected to the signal processing IC by wire bonding.

20. The current sensor according to claim 19, wherein: When viewed from a direction intersecting the thickness direction of the at least one magneto-electric transducer element, the magneto-sensitive surface of the at least one magneto-electric transducer element is arranged at a position overlapping with the side surface of the conductor portion provided with the at least one slit.

21. The current sensor according to claim 1, wherein: The at least one magneto-electric conversion element is a Hall element that detects a longitudinal magnetic field in a thickness direction of the conductor portion.

22. The current sensor according to claim 1, wherein: The at least one magneto-electric conversion element is a magnetoresistive element that detects a transverse magnetic field in a direction along the second surface of the conductor portion.

23. A current sensor comprising: at least one magnetoelectric conversion element; a first lead frame including a first terminal portion and a conductor portion connected to the first terminal portion, and a measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion; a signal processing IC disposed on a second surface side opposite to the first surface of the conductor portion, having a circuit surface on which the at least one magnetoelectric conversion element is disposed and opposite to the second surface, and processing a signal output from the at least one magnetoelectric conversion element; and a sealing portion, sealing the at least one magnetoelectric conversion element, the conductor portion and the signal processing IC, The conductor portion has: A first portion connected to the first terminal portion; and The second portion is arranged opposite to the circuit surface of the signal processing IC, is offset relative to the first portion in a direction away from the circuit surface of the signal processing IC in a thickness direction, and is connected to the first portion. The second portion has a third corner portion, and the third corner portion is located between a second end surface on the side connected to the first portion and a first surface on the opposite side of the second surface facing the circuit surface of the signal processing IC. An outer surface area of ​​the third corner portion is larger than an outer surface area of ​​a fourth corner portion located between the second end surface of the second portion and a first surface of the first portion on the same side as the first surface of the second portion.

24. The current sensor according to claim 23, wherein: The second end surface of the second portion has a shear surface.

25. A current sensor comprising: at least one magnetoelectric conversion element; a first lead frame including a first terminal portion and a conductor portion connected to the first terminal portion, and a measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion; a signal processing IC having a circuit surface on which the at least one magnetoelectric conversion element is disposed, and processing a signal output from the at least one magnetoelectric conversion element; a second lead frame including a second terminal portion and a support portion, and being electrically insulated from the first lead frame, wherein the second terminal portion is arranged opposite to the first terminal portion across the signal processing IC in a plan view and is electrically connected to the signal processing IC, and the support portion supports the signal processing IC using a first surface; and a sealing portion that seals the at least one magnetoelectric conversion element, the conductor portion, the signal processing IC, and the support portion, The conductor portion has a first shear surface, which is located closer to the first terminal portion than the signal processing IC when viewed from above, faces the second terminal portion, and is a step or end surface having the shear surface. The area of ​​the outer surface of the fifth corner among the corners of the first shear surface is larger than the area of ​​the outer surface of the sixth corner. The fifth corner is located on the side of the second surface opposite to the first surface of the support portion, and the sixth corner is located on the side away from the second surface.

26. A current sensor comprising: at least one magnetoelectric conversion element; a first lead frame including a first terminal portion and a conductor portion connected to the first terminal portion, and a measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion; a signal processing IC having a circuit surface on which the at least one magnetoelectric conversion element is disposed, and processing a signal output from the at least one magnetoelectric conversion element; a second lead frame including a second terminal portion and a support portion, and being electrically insulated from the first lead frame, wherein the second terminal portion is arranged opposite to the first terminal portion across the signal processing IC when viewed from above and is electrically connected to the signal processing IC, and the support portion supports the signal processing IC using a first surface; and a sealing portion that seals the at least one magnetoelectric conversion element, the conductor portion, the signal processing IC, and the support portion, The support portion has a seventh corner and an eighth corner, the seventh corner is located between the first surface supporting the signal processing IC and the second end surface on the first terminal portion side, and the eighth corner is located between the second surface on the opposite side of the first surface supporting the signal processing IC and the second end surface, An area of ​​an outer surface of the seventh corner portion is larger than an area of ​​an outer surface of the eighth corner portion.

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