Current sensor

Abstract

SOLUTION: To provide a current sensor comprising a first lead frame which includes a first terminal part and a conductor part coupled to the first terminal part, and in which a measurement current to be measured by at least one magnetoelectric transducer flows via the first terminal part and the conductor part, and comprising a signal processing IC which is disposed on the second surface side of the opposite side of the first surface of the conductor part, and which has a circuit surface on which at least one magnetoelectric transducer is disposed, to process a signal output from the at least one magnetoelectric transducer, wherein the conductor part has a first corner part between the first end face of the opposite side of the side coupled to the first terminal part and a second face opposing the signal processing IC, and a second corner part between the first end face and the first surface of the opposite side of the second surface opposing the signal processing IC, and wherein the area of the exterior surface of the first corner part is larger than the area of the exterior surface of the second corner part.SELECTED DRAWING: Figure 2

Description

Technical Field

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

Background Art

[0002] Patent Document 1 discloses a current sensor including a magnetic sensor and a signal processing IC, and a conductive wire that connects the magnetic sensor and the signal processing IC without crossing a primary conductor. [Prior Art Document] [Patent Document] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-036237

Summary of the Invention

[0003] The current sensor according to one aspect of the present invention may include at least one magnetoelectric conversion element. The current sensor may include a first terminal portion and a conductor portion connected to the first terminal portion, and may include a first lead frame through which a measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion. The current sensor may be disposed on a second surface side opposite to a first surface of the conductor portion, and may include a signal processing IC that has a circuit surface facing the second surface and processes a signal output from the at least one magnetoelectric conversion element. The current sensor may include a sealing portion that seals the at least one magnetoelectric conversion element, the conductor portion, and the signal processing IC. The conductor portion may have a first corner portion between a first end surface on a side opposite to the side connected to the first terminal portion and a second surface facing the signal processing IC, and a second corner portion between the first end surface and a first surface on a side opposite to the second surface facing the signal processing IC. The area of the outer surface of the first corner portion may be larger than the area of the outer surface of the second corner portion.

[0004] In the current sensor, the first corner portion may be a chamfered surface.

[0005] In any of the current sensors, when the first corner is projected in the direction along the first end face, the width in the direction along the second face of the conductor part, and when the first corner is projected in the direction along the second face of the conductor part, either one of the widths in the direction along the first end face may be greater than 15 μm and shorter than the thickness of the conductor part.

[0006] In any of the current sensors, the width in the direction along the second face of the conductor part when the first corner is projected in the direction along the first end face may be longer than the width in the direction along the first end face when the first corner is projected in the direction along the second face of the conductor part.

[0007] In any of the current sensors, the conductor part may have a first portion connected to the first terminal part and a second portion disposed to face the circuit surface of the signal processing IC and shifted from the first portion in a direction away from the circuit surface of the signal processing IC in the thickness direction and connected to the first portion. The second portion may have a third corner between a second end face on the side connected to the first portion and a first face on the side opposite to the second face facing the circuit surface of the signal processing IC. The area of the outer surface of the third corner may be larger than the area of the outer surface of a fourth corner between the second end face of the second portion and the first face on the same side as the first face of the first portion of the second portion.

[0008] In any of the current sensors, the third corner may be a chamfered surface.

[0009] In any of the current sensors, either one of the width in the direction along the first face on the side opposite to the second face of the conductor part when the third corner is projected in the direction along the second end face, and the width in the direction along the second end face when the third corner is projected in the direction along the first face of the conductor part may be greater than 15 μm and shorter than the thickness of the conductor part.

[0010] In any of the current sensors, the shift amount of the second portion with respect to the first portion may be 0.6 times or less the thickness of the conductor portion.

[0011] In any of the current sensors, the second end face of the second portion may have a shearing surface.

[0012] Any of the current sensors may include a second terminal portion that is disposed opposite the first terminal portion with the signal processing IC therebetween in a plan view and is electrically connected to the signal processing IC, and a support portion that supports a surface of the signal processing IC opposite to the circuit surface on the conductor portion side with a first surface, and may further include a second lead frame that is electrically insulated from the first lead frame. The first portion may have a fifth corner between a third end face on a side where the first portion is connected to the second portion and a second face on the same side as the second face of the second portion. The area of the outer surface of the fifth corner may be larger than the area of the outer surface of a sixth corner between the third end face of the first portion and the second face of the second portion.

[0013] In any of the current sensors, the fifth corner may be a chamfered surface.

[0014] In any of the current sensors, either the width in the direction along the second face of the first portion when the fifth corner is projected in the direction along the third end face, or the width in the direction along the third end face when the fifth corner is projected in the direction along the second face of the first portion may be larger than 15 μm and shorter than the thickness of the conductor portion.

[0015] In any of the current sensors, the support portion may have a seventh corner between the first surface that supports the signal processing IC and a fourth end face on the first terminal portion side, and an eighth corner between a second surface opposite to the first surface that supports the signal processing IC and the fourth end face. The area of the outer surface of the seventh corner may be larger than the area of the outer surface of the eighth corner.

[0016] In any of the above current sensors, the sealing portion is made of a molding resin, the molding resin contains a filler having a diameter of 20 µm or more, and the filling rate of the filler may be 60% or more.

[0017] In any of the above current sensors, the at least one magnetoelectric conversion element may protrude from the circuit surface to a position overlapping the conductor portion when viewed from a direction intersecting the thickness direction of the at least one magnetoelectric conversion element.

[0018] In any of the above current sensors, the at least one magnetoelectric conversion element may be composed of a chip separate from the chip constituting the signal processing IC.

[0019] In any of the above current sensors, the at least one magnetoelectric conversion element may be built in the chip constituting the signal processing IC.

[0020] In any of the above current sensors, the conductor portion may have at least one slit portion. The at least one magnetoelectric 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.

[0021] In any of the above current sensors, in a plan view, the at least one magnetoelectric conversion element may be fixed to the circuit surface by die bonding and electrically connected to the signal processing IC by wire bonding within the at least one slit portion.

[0022] In any of the above current sensors, the magneto-sensitive surface of the at least one magnetoelectric conversion element may be disposed at a position overlapping the side surface provided with the at least one slit of the conductor portion when viewed from a direction intersecting the thickness direction of the at least one magnetoelectric conversion element.

[0023] In any of the above current sensors, the at least one magnetoelectric conversion element may be a Hall element that detects a longitudinal magnetic field in the thickness direction of the conductor portion.

[0024] In any of the above current sensors, the at least one magnetoelectric conversion element may be a magnetoresistive element that detects a transverse magnetic field in the direction along the second surface of the conductor portion.

[0025] A current sensor according to one aspect of the present invention may include at least one magnetoelectric conversion element. The current sensor includes a first terminal portion and a conductor portion connected to the first terminal portion, and may include a first lead frame through which a measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion. The current sensor is disposed 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 disposed and that faces the second surface, and may include a signal processing IC that processes a signal output from the at least one magnetoelectric conversion element. The current sensor may include a sealing portion that seals the at least one magnetoelectric conversion element, the conductor portion, and the signal processing IC. The conductor portion may have a first portion connected to the first terminal portion and a second portion that is disposed to face the circuit surface of the signal processing IC and that is shifted from the first portion in a direction away from the circuit surface of the signal processing IC in the thickness direction and is connected to the first portion. The second portion may have a third corner portion between a second end surface on the side connected to the first portion and a first surface on the side opposite to the second surface facing the circuit surface of the signal processing IC. The area of the outer surface of the third corner portion may be larger than the area of the outer surface of a fourth corner portion between the second end surface of the second portion and a first surface on the same side as the first surface of the first portion of the second portion.

[0026] In any of the above current sensors, the second end surface of the second portion may have a shearing surface.

[0027] A current sensor according to an aspect of the present invention may include at least one magnetoelectric conversion element. The current sensor includes a first terminal portion and a conductor portion connected to the first terminal portion, and may include a first lead frame through which a measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion. The current sensor may have a circuit surface on which the at least one magnetoelectric conversion element is disposed, and may include a signal processing IC that processes a signal output from the at least one magnetoelectric conversion element. The current sensor includes a second terminal portion that is disposed to face 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 a support portion that supports the signal processing IC on a first surface, and may include a second lead frame that is electrically insulated from the first lead frame. The current sensor may include 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 is on the side of the first terminal portion rather than the signal processing IC in a plan view, faces the second terminal portion side, has a first shear surface that is a step or an end surface having a shear surface, and among the corners of the first shear surface, the area of the outer surface of the fifth corner portion closer to the second surface on the opposite side of the first surface of the support portion may be larger than the area of the outer surface of the sixth corner portion farther from the second surface.

[0028] A current sensor according to an aspect of the present invention may include at least one magnetoelectric conversion element. The current sensor includes a first terminal portion and a conductor portion connected to the first terminal portion, and may include a first lead frame through which a measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion. The current sensor may have a circuit surface on which the at least one magnetoelectric conversion element is disposed, and may include a signal processing IC that processes a signal output from the at least one magnetoelectric conversion element. The current sensor includes a second terminal portion that is disposed 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 a support portion that supports the signal processing IC on a first surface, and may include a second lead frame that is electrically insulated from the first lead frame. The current sensor may include 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 may have a seventh corner portion between the first surface that supports the signal processing IC and a second end surface on the first terminal portion side, and an eighth corner portion between the second surface opposite to the first surface that supports the signal processing IC and the second end surface. An area of an outer surface of the seventh corner portion may be larger than an area of an outer surface of the eighth corner portion.

[0029] A current sensor according to an aspect of the present invention may include at least one magnetoelectric conversion unit. The current sensor includes a first terminal portion and a conductor portion connected to the first terminal portion, and may include a first lead frame through which a measurement current measured by the at least one magnetoelectric conversion unit flows through the first terminal portion and the conductor portion. The current sensor is a signal processing unit disposed on a second surface side opposite to a first surface of the conductor portion, has a circuit surface facing the second surface of the conductor portion, and is provided with a signal processing unit that processes a signal output from the at least one magnetoelectric conversion unit disposed on the circuit surface. The current sensor may include a second lead frame including a support portion that supports a support surface opposite to the circuit surface of the signal processing unit with a first surface, and a second terminal portion that is connected to the support portion and outputs a signal from the signal processing unit. The current sensor may include a sealing portion that seals the at least one magnetoelectric conversion unit, the conductor portion, the signal processing unit, and the support portion. The conductor portion may have a first corner portion between a first end surface on a side opposite to the side connected to the first terminal portion and a second surface facing the signal processing unit, and a second corner portion between the first end surface and the first surface of the conductor portion. The support portion may have a third corner portion between a second end surface on a side opposite to the side connected to the second terminal portion and the first surface of the support portion that supports the signal processing unit, and a fourth corner portion between the second end surface and a second surface opposite to the first surface of the support portion. 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, or the area of the outer surface of the fourth corner portion may be larger than the area of the outer surface of the third corner portion.

[0030] In the current sensor, when 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, the conductor portion may be bent and connected to the first terminal portion so as to approach the second surface on the second surface side of the support portion in the sealing portion.

[0031] In any of the current sensors, an area of an outer surface of the second corner portion is larger than an area of an outer surface of the first corner portion, and the conductor portion may be bent so as to approach a second surface on a side of the support portion in the sealing portion and connected to the first terminal portion, where a surface of a portion of the second surface of the conductor portion that is connected to the first terminal portion is not less than half of a thickness of the conductor portion, with respect to a surface of the second surface of the conductor portion that faces a circuit surface of the signal processing portion.

[0032] In any of the current sensors, an area of an outer surface of the fourth corner portion is larger than an area of the third corner portion, and the support portion may be bent so as to approach a first surface on a side of the conductor portion in the sealing portion and connected to the second terminal portion.

[0033] In any of the current sensors, an area of an outer surface of the fourth corner portion is larger than an area of the third corner portion, and the support portion may be bent so as to approach a first surface on a side of the conductor portion in the sealing portion and connected to the second terminal portion, where a surface of a portion of the first surface of the support portion that is connected to the second terminal portion is not less than half of a thickness of the support portion, with respect to a surface of the first surface of the support portion that supports the signal processing portion.

[0034] In any of the current sensors, an area of an outer surface of the second corner portion is larger than an area of an outer surface of the first corner portion, and the second corner portion may be a chamfered surface.

[0035] In any of the current sensors, an area of an outer surface of the fourth corner portion is larger than an area of an outer surface of the third corner portion, and the fourth corner portion may be a chamfered surface.

[0036] At a predetermined minimum temperature, a linear expansion coefficient of the first lead frame or the second lead frame may be larger than a linear expansion coefficient of a mold resin constituting the sealing portion.

[0037] In any of the above current sensors, when 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, either the width in the direction along the first surface of the conductor portion when the second corner portion is projected in the direction along the first end surface, or the width in the direction along the first end surface when the second corner portion is projected in the direction along the first surface of the conductor portion may be larger than 15 μm and shorter than the thickness of the conductor portion.

[0038] In any of the above current sensors, the encapsulation portion is made of a mold resin, the mold resin contains fillers with a diameter of 20 μm or more, and the filling rate of the fillers may be 60% or more.

[0039] In any of the above current sensors, when 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, either the width in the direction along the second surface of the support portion when the fourth corner portion is projected in the direction along the second end surface, or the width in the direction along the second end surface when the fourth corner portion is projected in the direction along the second surface of the support portion may be larger than 15 μm and shorter than the thickness of the support portion.

[0040] In any of the above current sensors, the encapsulation portion is made of a mold resin, the mold resin contains fillers with a diameter of 20 μm or more, and the filling rate of the fillers may be 60% or more.

[0041] In any of the above current sensors, the conductor portion may be covered with the mold resin constituting the encapsulation portion and may have no interface with other than the mold resin.

[0042] In any of the above current sensors, the first lead frame may be thicker than the second lead frame.

[0043] In any of the current sensors, the first terminal portion may protrude from the first side surface of the sealing portion, and the second terminal portion may protrude from the second side surface facing 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. Let the distance between the first surface on the first surface side of the conductor portion in the sealing portion and the first surface of the conductor portion be t1, the width in a second direction intersecting the first direction along the first surface of the conductor portion of the portion of the conductor portion facing the signal processing portion be l1, the distance between the second surface of the conductor portion and the circuit surface of the signal processing portion be t2, and the width in the second direction along the circuit surface of the signal processing portion be l2. In this case, l1 / t1 > l2 / t2 may be satisfied.

[0044] In any of the current sensors, the first terminal portion may protrude from the first side surface of the sealing portion, and the second terminal portion may protrude from the second side surface facing 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. Let the distance between the second surface on the second surface side of the support portion in the sealing portion and the second surface of the support portion be t3, the width in a second direction intersecting the first direction along the second surface of the support portion of the portion of the support portion supporting the signal processing portion be l3, the distance between the second surface of the conductor portion and the circuit surface of the signal processing portion be t2, and the width in the second direction along the circuit surface of the signal processing portion be l2. In this case, l3 / t3 > l2 / t2 may be satisfied.

[0045] In any of the current sensors, the signal processing portion may be an IC chip. The at least one magnetoelectric conversion portion may be a magnetoelectric conversion element separate from the IC chip. The magnetosensitive surface of the magnetoelectric conversion element may protrude from the surface facing the conductor portion of the IC chip.

[0046] In any of the current sensors, the signal processing portion may be an IC chip. The magnetoelectric conversion portion may be built in the IC chip. The magnetosensitive surface of the magnetoelectric conversion portion may not protrude from the surface facing the conductor portion of the IC chip.

[0047] Note that the above summary of the invention does not list all the features of the present invention. Also, sub-combinations of these feature groups can also be inventions.

Brief Description of the Drawings

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Mode for Carrying Out the Invention

[0049] Hereinafter, the present invention will be described through embodiments of the invention. However, the following embodiments do not limit the invention according to the claims. Also, not all combinations of features described in the embodiments are essential for the solution means of the invention.

[0050] FIGS. 1A and 1B show the internal configuration of a semiconductor package that functions as a current sensor 10 according to the first embodiment. FIG. 1A is a schematic plan view of the current sensor 10 according to the first embodiment as viewed from the ceiling surface side (Z-axis direction). FIG. 1B is a cross-sectional view taken along line A-A of the current sensor 10 shown in FIG. 1A.

[0051] The coordinates are defined in FIG. 1A as follows: the direction parallel to the paper surface and from bottom to top is the X-axis direction, the direction parallel to the paper surface and from right to left is the Y-axis direction, and the direction perpendicular to the paper surface and from back to front is the Z-axis direction. Any one of the X-axis, Y-axis, and Z-axis is orthogonal to the other axes.

[0052] The current sensor 10 includes a signal processing IC 100, a magnetoelectric conversion element 20a, a magnetoelectric conversion element 20b, a lead frame 140 on the current conductor side, a lead frame 150 on the signal terminal side, and a sealing portion 130.

[0053] 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 within the sealing portion 130 and partially surrounds the magnetoelectric conversion element 20a and the magnetoelectric conversion element 20b. A measurement current flows through the terminal portion 142 and the conductor portion 141. The pair of terminals 142a and 142b are physically integrally formed with the conductor portion 141 and are exposed outside the sealing portion 130. The lead frame 140 is an example of a first lead frame.

[0054] The lead frame 140 does not necessarily need to be manufactured in a form in which a plurality of metal plates are connected to form the conductor portion 141 and the terminal portion 142, and may be manufactured using individual metal parts.

[0055] 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 within the sealing portion 130 and supports the signal processing IC 100. Some of the plurality of terminals 152a are physically integrally formed with the support portion 154. At least a part of each of the plurality of terminals 152a is exposed outside 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 may be made of a conductive material mainly composed of copper. The support portion 154 may be composed of a metal plate separate from the lead frame 150, a plate made of a semiconductor, or an insulating member such as a die attach film.

[0056] A pair of terminals 142a and 142b and a plurality of terminals 152a are arranged to face each other via 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 the plane (XY plane) orthogonal to the thickness direction. The pair of terminals 142a and 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 opposite to the side surface 130a of the sealing portion 130. As shown in FIG. 1B, the pair of terminals 142a and 142b and the plurality of terminals 152a may protrude outward from different heights in the thickness direction of the sealing portion 130 of the opposing side surfaces 130a and 130b of the sealing portion 130. A surface 1521 on the same side as the surface 100a of the signal processing IC 100 of the plurality of terminals 152a may be located at the same height as a surface 1421 on the same side as the surface on the opposite side of the surface 100a of the signal processing IC 100 of the pair of terminals 142a and 142b in the thickness direction (Z-axis direction) of the sealing portion 130. Alternatively, the surface 1521 of the plurality of terminals 152a may be located below the surface 1421 of the pair of terminals 142a and 142b in the thickness direction of the sealing portion 130.

[0057] That is, the height in the thickness direction (Z-axis direction) of the sealing portion 130 of the surface 1521 on the same side as the surface 100a of the signal processing IC 100 of the plurality of terminals 152a at the position where it intersects the side surface 130a of the sealing portion 130 and the height in the thickness direction (Z-axis direction) of the sealing portion 130 of the surface 1421 on the same side as the surface on the opposite side of the surface 100a of the signal processing IC 100 of the pair of terminals 142a and 142b at the position where it intersects the side surface 130b of the sealing portion 130 may be the same. Alternatively, the height in the thickness direction (Z-axis direction) of the sealing portion 130 of the surface 1521 of the plurality of terminals 152a at the position where it intersects the side surface 130a of the sealing portion 130 may be located below the height in the thickness direction (Z-axis direction) of the sealing portion 130 of the surface 1421 of the pair of terminals 142a and 142b at the position where it intersects the side surface 130b of the sealing portion 130.

[0058] The pair of terminals 142a and 142b protrude from the side surface 130a to the negative side in the Y-axis direction, and are further bent to 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 are further bent to the negative side in the Z-axis direction. The pair of terminals 142a and 142b may protrude from the side surface 130a to the negative side in the Y-axis direction and may be further bent to the positive side in the Z-axis direction. The plurality of terminals 152a may protrude from the side surface 130b toward the positive side in the Y-axis direction and may be further bent to the positive side in the Z-axis direction. The pair of terminals 142a and 142b and the plurality of terminals 152a may not be bent. That is, the pair of terminals 142a and 142b may protrude from the side surface 130a to the negative side in the Y-axis direction and may not be bent to the positive side and the negative side in the Z-axis direction. The plurality of terminals 152a may protrude from the side surface 130b toward the positive side in the Y-axis direction and may not be bent to the positive side and the negative side in the Z-axis direction.

[0059] The support portion 154 may have a stepped portion 155 in which the portion supporting the signal processing IC 100 is recessed in a direction away from the conductor portion 141 in the thickness direction (Z-axis direction) (the bottom surface side of the sealing portion 130). The stepped portion 155 is an example of a first stepped portion. The signal processing IC 100 may be fixed on the surface 154a of the portion supporting the signal processing IC 100 via an adhesive layer. The adhesive layer may be a die attach film. The lead frame 140 has a stepped portion 144 in which the opposing portion facing the signal processing IC 100 protrudes in a direction away from the signal processing IC 100 in the thickness direction. The stepped portion 144 is an example of a second stepped portion. The stepped portion 155 and the stepped portion 144 may be formed by performing semi-through machining on the lead frame 150 and the lead frame 140. In that case, there are shearing surfaces on the stepped portion 155 and the stepped portion 144.

[0060] The conductor portion 141 has two slit portions 141a and 141b. The magnetoelectric conversion elements 20a are arranged within the slit portion 141a in a plan view and are thus partially surrounded by the conductor portion 141. The magnetoelectric conversion elements 20b are arranged within the slit portion 141b in a plan view and are thus partially surrounded by the conductor portion 141. The magnetoelectric conversion elements 20a and 20b may be fixed to the circuit surface of the signal processing IC 100 by die bonding and may be electrically connected to the signal processing IC 100 by wire bonding. That is, the magnetoelectric conversion elements 20a and 20b may be electrically connected to the signal processing IC 100 via a plurality of wires 22a and 22b. The magnetoelectric conversion elements 20a and 20b may be electrically connected to the signal processing IC 100 by flip chip bonding. The magnetoelectric conversion elements 20a and 20b output signals processed by the signal processing IC 100 to the signal processing IC 100. The magnetoelectric conversion elements 20a and 20b may be configured separately from the signal processing IC 100. That is, the magnetoelectric conversion elements 20a and 20b may be formed of chips separate from the chips constituting the signal processing IC 100. The magnetoelectric conversion elements 20a and 20b may be incorporated within the chips constituting the signal processing IC 100.

[0061] The magnetosensing surfaces of the magnetoelectric conversion elements 20a and 20b may be arranged at positions overlapping 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.

[0062] The signal processing IC 100 is electrically connected to a plurality of terminals 152a via a wire 108. The wires 22a, 22b and the wire 108 may be formed of a conductor material mainly composed of Au, Ag, Cu, or Al.

[0063] The magnetoelectric conversion elements 20a and 20b may protrude from the surface 100a of the signal processing IC 100 such that the magnetosensing surfaces of the magnetoelectric conversion elements 20a and 20b overlap the conductor portion 141 in a side view. Thereby, the sensitivity of the magnetoelectric conversion elements 20a and 20b can be increased.

[0064] 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 portion 141, and the signal processing IC 100 amplifies a signal corresponding to the magnitude of the magnetic field and outputs the amplified signal via the terminal 152a. The magnetoelectric conversion elements 20a and 20b may be made of a compound semiconductor formed on a GaAs substrate and may be chips cut out in a square or rectangular shape in a plan view from the Z-axis direction.

[0065] The magnetoelectric conversion elements 20a and 20b may include a substrate made of silicon or a compound semiconductor, and a magnetoelectric conversion portion provided on the substrate. The thickness of the substrate is adjusted by polishing the surface on the negative side in the Z-axis direction. Since a magnetic field in the Z-axis direction is to be detected, for example, a Hall element that detects a longitudinal magnetic field in the thickness direction of the conductor portion 141 is suitable as the magnetoelectric conversion elements 20a and 20b. Also, if the magnetoelectric conversion elements 20a and 20b are arranged at a position to detect a magnetic field in any one 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, they may be arranged so as to overlap the conductor 141 in a plan view from the Z-axis direction. FIGS. 1C and 1D are examples of the current sensor 10 in which magnetoelectric conversion elements are arranged at positions to detect a magnetic field in the X-axis direction. FIG. 1C shows the internal configuration of a semiconductor package that functions as the current sensor 10 according to a modification of the first embodiment. FIG. 1C is a schematic plan view seen from the ceiling surface side (Z-axis direction) of the current sensor 10 according to a modification of the first embodiment. FIG. 1D is a cross-sectional view taken along line A-A of the current sensor 10 shown in FIG. 1C. In the current sensor 10 according to a modification of the first embodiment, the magnetoelectric conversion elements 20a and 20b are built in the chip constituting the signal processing IC 100.

[0066] The signal processing IC 100 is a large-scale integrated circuit (LSI). The signal processing IC 100 is a monolithic IC. More specifically, the signal processing IC 100 is a signal processing circuit composed of a Si monolithic semiconductor formed on a Si substrate. The signal processing IC 100 has a circuit surface on which the magnetoelectric conversion elements 20a and 20b are arranged. In the first embodiment, the circuit surface is a surface 100a corresponding to the ceiling surface of the semiconductor package constituting the signal processing IC 100. The surface 100a is an example of the first surface of the signal processing IC 100. The signal processing circuit processes an output signal according to the magnitude of the magnetic field output from the magnetoelectric conversion elements 20a and 20b. The signal processing circuit corrects the measurement current flowing through the conductor portion 141 based on the output signal, and outputs an output signal indicating an accurate current value via the terminal 152a. The signal processing circuit reduces the noise components included in the output signal of the magnetoelectric conversion element 20a and the output signal of the magnetoelectric conversion element 20b based on the difference between the output signal of the magnetoelectric conversion element 20a and the output signal of the magnetoelectric conversion element 20b, amplifies the output signal of the magnetoelectric conversion element 20a and the output signal of the magnetoelectric conversion element 20b with the noise components reduced, calculates the current value of the measurement current based on the amplified output signal, and outputs an output signal indicating the current value.

[0067] The sealing portion 130 seals the magnetoelectric conversion elements 20a and 20b, the conductor portion 141, the support portion 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, an epoxy-based thermosetting resin added with silica, and may be formed into a semiconductor package by transfer molding.

[0068] FIG. 2 shows an example of an enlarged view of the surrounded portion indicated by reference numeral 300 shown in FIG. 1B. The conductor portion 141 has a first portion 1411 connected to the terminal portion 142, and a second portion 1412 that is disposed to face the surface 100a of the signal processing IC 100 and is shifted from the first portion 1411 in a direction away from the surface 100a of the signal processing IC 100 in the thickness direction and is connected to the first portion 1411. The second portion 1412 is shifted from the first portion 1411 due to the semi-through processing of the conductor portion 141.

[0069] The second part 1412 has a first corner 1401 between a first end face 1412c on a side opposite to the side connected to the terminal part 142 and a second face 1412b facing the signal processing IC 100, and a second corner 1402 between the first end face 1412c and a first face 1412a on a side opposite to the second face 1412b facing the signal processing IC 100. The second part 1412 has a third corner 1403 between a second end face 1412d on a side connected to the first part 1411 and a first face 1412a on a side opposite to the second face 1412b facing the face 100a of the signal processing IC 100. The first part 1411 has a fifth corner 1405 between a third end face 1411c on a side connected to the second part 1412 and a second face 1411b on the same side as the second face 1412b of the second part 1412.

[0070] The support part 154 of the lead frame 150 has a seventh corner 1501 between a face 154a supporting the signal processing IC 100 and a fourth end face 154c on the terminal part 142 side, and an eighth corner 1502 between the face 154a supporting the signal processing IC 100 and a second face 154b on a side opposite thereto and the fourth end face 154c.

[0071] Here, the first corner 1401, the third corner 1403, the fifth corner 1405, and the seventh corner 1501 are each chamfered faces. The area of the outer face of the first corner 1401 is larger than the area of the outer face of the second corner 1402. The area of the outer face of the first corner 1401 is the area of the chamfered face. The area of the outer face of the first corner 1401 is the area of the outer face defined from the boundary between the second face 1412b and the first corner 1401 to the boundary between the first end face 1412c and the first corner 1401. The area of the outer face of the second corner 1402 is the area of the outer face defined from the boundary between the first end face 1412c and the second corner 1402 to the boundary between the first face 1412a and the second corner. The second corner 1402 can be a substantially straight line along the X-axis direction. The area of the outer face of the second corner 1402 can be substantially zero.

[0072] The area of the outer surface of the third corner portion 1403 is larger than the area of the outer surface of the fourth corner portion 1404 between the second end surface 1412d of the second portion 1412 and the first surface 1411a on the same side as the first surface 1412a of the second portion 1412 of the first portion 1411. The area of the outer surface of the third corner portion 1403 is the area of the chamfered surface. The area of the outer surface of the third corner portion 1403 is the area of the outer surface defined from the boundary between the first surface 1412a and the third corner portion 1403 to the boundary between the second end surface 1412d and the third corner portion 1403. The area of the outer surface of the fourth corner portion 1404 is the area of the outer surface defined from the boundary between the second end surface 1412d and the fourth corner portion 1404 to the boundary between the first surface 1411a and the fourth corner portion 1404. The fourth corner portion 1404 can be a substantially straight line along the X-axis direction. The area of the outer surface of the fourth corner portion 1404 can be substantially zero.

[0073] The area of the outer surface of the fifth corner portion 1405 is larger than the area of the outer surface of the sixth corner portion 1406 between the third end surface 1411c of the first portion 1411 and the second surface 1412b of the second portion 1412. The area of the outer surface of the fifth corner portion 1405 is the area of the chamfered surface. The area of the outer surface of the fifth corner portion 1405 is the area of the outer surface defined from the boundary between the third end surface 1411c and the fifth corner portion 1405 to the boundary between the fifth corner portion 1405 and the second surface 1411b. The area of the outer surface of the sixth corner portion 1406 is the area of the outer surface defined from the boundary between the second surface 1412b and the sixth corner portion 1406 to the boundary between the sixth corner portion 1406 and the third end surface 1411c. The sixth corner portion 1406 can be a substantially straight line along the X-axis direction. The area of the outer surface of the sixth corner portion 1406 can be substantially zero.

[0074] 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 1502. The area of the outer surface of the seventh corner portion 1501 is the area of the chamfered surface. The area of the outer surface of the seventh corner portion 1501 is the area of the outer surface defined from the boundary between the surface 154a and the seventh corner portion 1501 to the boundary between the seventh corner portion 1501 and the fourth end surface 154c. The area of the outer surface of the eighth corner portion 1502 is the area of the outer surface defined from the boundary between the surface 154b and the eighth corner portion 1502 to the boundary between the eighth corner portion 1502 and the fourth end surface 154c. The eighth corner portion 1502 can be a substantially straight line along the X-axis direction. The area of the outer surface of the eighth corner portion 1502 can be substantially zero.

[0075] By chamfering each of the first corner portion 1401, the third corner portion 1403, the fifth corner portion 1405, and the seventh corner portion 1501 in this way, it is possible to suppress the concentration of the electric field and the concentration of stress in the vicinity of the corner portion, and improve the durability of the current sensor 10. That is, it is possible to suppress the occurrence of withstand voltage failure due to the short distance between the signal processing IC 100 and the conductor portion 141.

[0076] The chamfering shape of each of the first corner portion 1401, the third corner portion 1403, the fifth corner portion 1405, and the seventh corner portion 1501 may be an arbitrary shape, and may be composed of a plurality of surfaces combining a plurality of substantially flat surfaces. The chamfering shape may be composed of one substantially flat surface as shown in FIG. 5A described later, may be composed of one R surface (curved surface) as shown in FIG. 5B, or may be composed of two surfaces combining two substantially flat surfaces as shown in FIG. 5C. When the first corner portion 1401, the third corner portion 1403, the fifth corner portion 1405, and the seventh corner portion 1501 are R surfaces as shown in FIG. 5B, the area of the outer surface of the first corner portion 1401, the third corner portion 1403, the fifth corner portion 1405, and the seventh corner portion 1501 is the area of the curved surface portion. The boundaries between the first corner portion 1401, the third corner portion 1403, the fifth corner portion 1405, and the seventh corner portion 1501 and their respective adjacent surfaces are the portions where the respective curved surfaces start.

[0077] The reasons for suppressing the concentration of electric fields or stress near the corner portions by chamfering each of the first corner portion 1401, the third corner portion 1403, the fifth corner portion 1405, and the seventh corner portion 1501 will be described below.

[0078] FIG. 3A shows an example of the simulation result of the 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. During the process of applying the measured current, the terminal portion 142 may reach a high voltage. FIG. 3B shows an example of the simulation result of the 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 chamfered. FIGS. 3A and 3B show the plots of the electric field contour lines. Comparing FIGS. 3A and 3B, it can be seen that near the first corner portion 1401, the electric field contour line shown in FIG. 3A is denser than the electric field contour line shown in FIG. 3B. That is, it can be understood that without chamfering, the electric field is more likely to concentrate near the first corner portion 1401.

[0079] When the current conductor side lead frame 140 and the signal terminal side lead frame 150 are stacked in the thickness direction, the part where the electric field is most likely to concentrate is the first corner portion 1401 of the second part 1412 of the conductor portion 141 of the current conductor side lead frame 140. Therefore, by chamfering the first corner portion 1401 of the second part 1412, the concentration of the electric field can be suppressed, and the durability of the current sensor 10 can be improved.

[0080] FIG. 4 shows an example of the relationship between the chamfer size and the maximum electric field. As shown in FIG. 4, even by performing chamfering of about 25 μm, the maximum electric field can be significantly reduced.

[0081] The molding resin that constitutes the sealing portion 130 contains a large amount of filler. The molding resin contains fillers with a filler diameter (diameter) of 20 μm or more, and the filling rate of the fillers is 60% or more. The mode value of the diameter of the fillers contained in the molding resin is about 20 μm. And when there are spheres with a diameter of about 20 μm in three dimensions, when viewed on the line segment of the chamfered portion, the dimension decreases to one dimension, so the filler diameter is 15 μm (20 μm × (√3 / 2) 2 ) or so. And when discharge is about to occur, the fillers prevent the discharge path, making it difficult for discharge to occur. Therefore, if the width of the chamfered surface is equal to or greater than the filler diameter, the possibility of fillers existing in the chamfered portion becomes very high, and discharge can be made difficult to occur. Note that the simulation results shown in FIG. 4 are the results of simulation assuming that the fillers are uniformly contained in the molding resin.

[0082] FIGS. 5A, 5B, and 5C show an example of the chamfered shape of the first corner portion 1401. Let the width in the first direction Y-axis when the first corner portion 1401 is projected in the Z-axis direction be width w1, and let the width in the Z-axis direction along the first end face 1412c when the first corner portion 1401 is projected in the Y-axis direction along the second face 1412b of the conductor portion 141 be width w2. In this case, either one of the width w1 and the width w2 is larger than 15 μm and shorter than the thickness of the conductor portion 141. Thereby, as described above, the possibility of fillers existing in the chamfered portion can be increased.

[0083] Also, even when the first corner portion 1401 is chamfered, electric field concentration occurs at the corner. In particular, the electric field tends to concentrate at the corner closer to the signal processing IC 100. Therefore, as shown in FIG. 5C, it is preferable that the width w1 is longer than the width w2. Thereby, the concentration of the electric field near the first corner portion 1401 can be further reduced.

[0084] As described above, the second portion 1412 is shifted with respect to the first portion 1411 by semi-perforating the conductor portion 141. By shifting the second portion 1412 with respect to the first portion 1411 in this way by semi-perforating, 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 that the conductor portion 141 comes into contact with the signal processing IC 100 due to manufacturing errors in the manufacturing process can be reduced.

[0085] On the other hand, for example, in the manufacturing process of the current sensor 10, when the lead frame 140 is pressed or the current sensor 10 vibrates while the current sensor 10 is mounted, stress may be generated in the sealing portion 130. In this case, the stress concentrates at the corners of the lead frame 140. In particular, the stress concentrates in the portion near the outer surface of the sealing portion 130, that is, near the third corner portion 1403. The third corner portion 1403 generated by semi-perforating is sharper than in the case of using other processing methods for forming steps, such as bending. Therefore, near the third corner portion 1403, cracks are more likely to occur in the sealing portion 130 than in other portions.

[0086] FIGS. 6A and 6B show the simulation results of the equivalent stress near the third corner portion 1403. FIG. 6A shows an example of the simulation result of the equivalent stress in a structure where the third corner portion 1403 is not chamfered. FIG. 6B shows an example of the simulation result of the equivalent stress in a structure where the third corner portion 1403 is chamfered. The portion where the stress contour lines are denser is the portion where the stress is more concentrated. Therefore, as shown in FIGS. 6A and 6B, it can be seen that by chamfering the third corner portion 1403, the concentration of stress near the third corner portion 1403 can be suppressed. That is, by chamfering the third corner portion 1403, the occurrence of cracks can be suppressed.

[0087] FIG. 7 shows an example of the relationship between the chamfer size and the equivalent stress size. As shown in FIG. 7, the larger the chamfer, the more the equivalent stress can be reduced.

[0088] Here, when a microcrack occurs at a location with a large equivalent stress, in order to suppress crack propagation, it is important to increase the toughness of that location. When peeling occurs at the interface between the filler and the base material in the mold resin, since the energy of peeling is high, including the filler can increase the toughness against cracks in the base material such as epoxy, which is a brittle material. Therefore, it is preferable that an interface between the filler and the base material exists in the chamfered region where stress is concentrated.

[0089] As described above, the mold resin contains fillers with a filler diameter (diameter) of 20 μm or more, and the filling rate of the fillers is 60% or more. When viewed on the line segment of the chamfered portion, since the dimension decreases to one dimension, the filler diameter is about 15 μm. Considering that the filling rate of the fillers is 60% or more, when the area is larger than 15 μm × 0.4 / 0.6 = 10 μm, there is a higher probability that an interface between the filler and the base material exists in the chamfered region. Therefore, it is preferable to ensure that the length of the side of the chamfered surface is 10 μm or more, preferably 15 μm or more, which is the one-dimensional filler diameter.

[0090] Therefore, when the third corner portion 1403 is projected in the direction (Z-axis direction) along the second end face 1412d, the width in the direction (Y-axis direction) along the first face 1412a on the side opposite to the second face 1412b of the conductor portion 141, and when the third corner portion 1403 is projected in the direction (Y-axis direction) along the first face 1412a of the conductor portion 141, it is preferable that either the width in the direction (Z-axis) along the second end face 1412d is larger than 15 μm and shorter than the thickness of the conductor portion 141. Thereby, the initial propagation of cracks can be suppressed, and the reliability of the current sensor 10 can be further improved.

[0091] Also, as shown in FIG. 2, the shift amount S of the second portion 1412 with respect to the first portion 1411 is preferably 0.6 times or less of the thickness H of the conductor portion 141. Thereby, the amount by which the second portion 1412 protrudes with respect to the first portion 1411 becomes small, and the concentration of stress in the mold resin can be alleviated.

[0092] Figures 8A and 8B show the distribution of thermal stress when the temperature around the current sensor 10 is lowered and the molding resin shrinks. Figure 8A shows an example of the simulation result of thermal stress in a structure where the fifth corner 1405 and the seventh corner 1501 are not chamfered. Figure 8B shows an example of the simulation result of thermal stress in a structure where the fifth corner 1405 and the seventh corner 1501 are chamfered.

[0093] As shown in FIGS. 8A and 8B, the concentration of thermal stress in the region P1 near the fifth corner 1405 and the region P2 of the seventh corner 1501 when the fifth corner 1405 and the seventh corner 1501 are chamfered is alleviated compared to the concentration of thermal stress in the region P1 near the fifth corner 1405 and the region P2 of the seventh corner 1501 when the fifth corner 1405 and the seventh corner 1501 are not chamfered.

[0094] Similar to the case of the third corner 1403, either the width in the direction (Y-axis direction) along the second surface 1411b of the first portion 1411 when the fifth corner 1405 is projected in the direction (Z-axis direction) along the third end surface 1411c, or the width in the direction along the third end surface 1411c when the fifth corner 1405 is projected in the direction along the second surface 1411b of the first portion 1411 is preferably greater than 15 μm and shorter than the thickness of the conductor portion 141. Thereby, an interface between the filler and the base material can be easily present near the corner where thermal stress concentrates, the initial propagation of cracks can be suppressed, and the reliability of the current sensor 10 can be further improved.

[0095] In the first embodiment, the current sensor 10 includes two magnetoelectric conversion elements 20a and 20b. However, the current sensor 10 may include one or more magnetoelectric conversion elements.

[0096] In the current sensor 10 according to the first embodiment described above, an example in which each of the first corner portion 1401, the third corner portion 1403, the fifth corner portion 1405, and the seventh corner portion 1501 is chamfered has been described. However, even if only at least one of the first corner portion 1401, the third corner portion 1403, the fifth corner portion 1405, and the seventh corner portion 1501 is chamfered, it is effective in relaxing the concentration of the electric field or the stress.

[0097] FIG. 9 shows an example of an enlarged view of the vicinity of the conductor portion 141 of the current sensor 10 according to the second embodiment. In the second embodiment, only the third corner portion 1403 of the conductor portion 141 is chamfered. The outer surface area of the third corner portion 1403 is larger than the outer surface area of the fourth corner portion 1404 between the second end surface 1412d of the second portion 1412 and the first surface 1411a on the same side as the first surface 1412a of the second portion 1412 of the first portion 1411. Either the width in the direction (Y-axis direction) along the first surface 1412a on the side opposite to the second surface 1412b of the conductor portion 141 when the third corner portion 1403 is projected in the direction along the second end surface 1412d (Z-axis direction), or the width in the direction along the second end surface 1412d (Z-axis) when the third corner portion 1403 is projected in the direction along the first surface 1412a (Y-axis direction) of the conductor portion 141 may be larger than 15 μm and shorter than the thickness of the conductor portion 141. According to the current sensor 10 according to the second embodiment, by chamfering the third corner portion 1403, it is possible to suppress the concentration of stress in the vicinity of the third corner portion 1403 and suppress the occurrence of cracks.

[0098] FIG. 10 shows an example of an enlarged view of the vicinity of the conductor portion 141 of the current sensor 10 according to the third embodiment. In the third embodiment, only the fifth corner portion 1405 of the conductor portion 141 and the seventh corner portion 1501 of the indicating portion 154 are chamfered. Note that only either the fifth corner portion 1405 of the conductor portion 141 or the seventh corner portion 1501 of the indicating portion 154 may be chamfered. The outer surface area of the fifth corner portion 1405 is larger than the outer surface area of the sixth corner portion 1406 between the third end surface 1411c of the first portion 1411 and the second surface 1412b of the second portion 1412. The outer surface area of the seventh corner portion 1501 is larger than the outer surface area of the eighth corner portion 1502.

[0099] When the fifth corner portion 1405 is projected in the direction along the third end face 1411c (Z-axis direction), it is preferable that either the width in the direction along the second face 1411b of the first portion 1411 (Y-axis direction) or the width in the direction along the third end face 1411c when the fifth corner portion 1405 is projected in the direction along the second face 1411b of the first portion 1411 is greater than 15 μm and shorter than the thickness of the conductor portion 141.

[0100] When the seventh corner portion 1501 is projected in the direction along the fourth end face 154c (Z-axis direction), it is preferable that either the width in the direction along the face 154a of the support portion 154 (Y-axis direction) or the width in the direction along the fourth end face 154c of the support portion 154 when the seventh corner portion 1501 is projected in the direction along the face 154a of the support portion 154 is greater than 15 μm and shorter than the thickness of the support portion 154.

[0101] According to the current sensor 10 according to the third embodiment, an interface between the filler and the base material can be easily formed near the corner portion where thermal stress concentrates, the initial propagation of cracks can be suppressed, and the reliability of the current sensor 10 can be further improved.

[0102] FIG. 11 is a schematic plan view seen from the ceiling surface side (Z-axis direction) of the current sensor 10 according to the fourth embodiment. FIG. 12 shows an example of an enlarged view of the vicinity of the conductor portion 141 in the cross section taken along line A-A of the current sensor shown in FIG. 11.

[0103] The current sensor 10 according to the fourth embodiment is different from the current sensors 10 according to the first to third embodiments in that the conductor portion 141 does not have a slit portion surrounding the magnetoelectric conversion elements 20a and 20b.

[0104] In the fourth embodiment, the conductor portion 141 has a fifth corner portion 1405 between a surface 1411a on the same side as the surface 154a of the support portion 154 and a surface 1411b on the opposite side, and a third end surface 1411c on the terminal portion 152 side, and a sixth corner portion 1406 between the surface 1411a of the conductor portion 141 and the third end surface 1411c. The area of the outer surface of the fifth corner portion 1405 is larger than the area of the outer surface of the sixth corner portion 1406. Either the width in the direction along the surface 1411b of the conductor portion 141 when the fifth corner portion 1405 is projected in the direction along the third end surface 1411c (Z-axis direction), or the width in the direction along the third end surface 1411c when the fifth corner portion 1405 is projected in the direction along the surface 1411b of the conductor portion 141 is larger than 15 μm and shorter than the thickness of the conductor portion 141.

[0105] Further, the support portion 154 has a seventh corner portion 1501 between the surface 154a that supports the signal processing IC 100 and the fourth end surface 154c on the terminal portion 142 side, and an eighth corner portion 1502 between the surface 154b on the opposite side of the surface 154a that supports 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.

[0106] According to the current sensor 10 according to the fourth embodiment, an interface between the filler and the base material can be easily formed near the corner portion where thermal stress concentrates, the initial progress of cracks can be suppressed, and the reliability of the current sensor 10 can be further improved.

[0107] FIGS. 13A, 13B, and 13C show the internal configuration of a semiconductor package that functions as the current sensor 10 according to the fifth embodiment. FIG. 13A is a schematic plan view seen from the ceiling surface side (Z-axis direction) of the current sensor 10 according to the fifth embodiment. FIG. 13B is a cross-sectional view taken along line A-A of the current sensor 10 shown in FIG. 13A. FIG. 13C is a cross-sectional view taken along line B-B of the current sensor 10 shown in FIG. 13A. Hereinafter, descriptions of the constituent elements denoted by the same reference numerals as those described in the current sensor 10 shown in FIGS. 1A and 1B may be omitted.

[0108] The current sensor 10 includes a signal processing IC 100, magnetoelectric conversion elements 20a and 20b, a lead frame 140 on the current conductor side, a lead frame 150 on the signal terminal side, and a sealing portion 130. This is the same as the current sensor 10 according to the first embodiment.

[0109] 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 within the sealing portion 130 and supports the signal processing IC 100. Some of the plurality of terminals 152a are physically integrally formed with the support portion 151. At least a part of each of the plurality of terminals 152a is exposed outside 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 may be formed of a conductive material mainly composed of copper. The support portion 151 may be configured in combination with a metal plate separate from the lead frame 150, a plate formed of a semiconductor, or an insulating member such as a die attach film.

[0110] The pair of terminals 142a and 142b and the plurality of terminals 152a are arranged to face each other via 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 and 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 opposite to the side surface 130a of the sealing portion 130.

[0111] As shown in FIG. 13B, 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 on the opposing side surfaces 130a and 130b of the sealing portion 130. A surface 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 a surface 1421 of the pair of terminals 142a, 142b on the same side as the surface on the opposite side of the first surface 100a of the signal processing IC 100 in the thickness direction (Z-axis direction) of the sealing portion 130. Alternatively, the surface 1521 of the plurality of terminals 152a may be located below the surface 1421 of the pair of terminals 142a, 142b in the thickness direction of the sealing portion 130.

[0112] That is, the height in the thickness direction (Z-axis direction) of the sealing portion 130 of the surface 1521 of the plurality of terminals 152a on the same side as the first surface 100a of the signal processing IC 100 at the position where it intersects with the side surface 130a of the sealing portion 130 and the height in the thickness direction (Z-axis direction) of the sealing portion 130 of the surface 1421 of the pair of terminals 142a, 142b on the same side as the surface on the opposite side of the first surface 100a of the signal processing IC 100 at the position where it intersects with the side surface 130b of the sealing portion 130 may be the same. Alternatively, the height in the thickness direction (Z-axis direction) of the sealing portion 130 of the surface 1521 of the plurality of terminals 152a at the position where it intersects with the side surface 130a of the sealing portion 130 may be located below the height in the thickness direction (Z-axis direction) of the sealing portion 130 of the surface 1421 of the pair of terminals 142a, 142b at the position where it intersects with the side surface 130b of the sealing portion 130.

[0113] When the lead frame 140 and the lead frame 150 are arranged to overlap in the thickness direction, in order to ensure insulation between the lead frame 140 and the lead frame 150 or the signal processing IC 100, it is necessary to provide a step in the thickness direction on at least one of the lead frame 140 and the lead frame 150.

[0114] The conductor portion 141 is bent and 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 within the sealing portion 130. The conductor portion 141 is such that the surface of the second surface 141b of the conductor portion 141 that is connected to the terminal portion 142 is more than half of the thickness of the conductor portion 141 from the surface of the second surface 141b of the conductor portion 141 that faces the first surface 100a which is the circuit surface of the signal processing IC 100, and is bent and 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. That is, the height difference between the surface of the second surface 141b of the conductor portion 141 that faces 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 that is connected to the terminal portion 142 may be more than half of the thickness of the conductor portion 141. The conductor portion 141 may be curved and 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 within the sealing portion 130. The conductor portion 141 may be curved by bending.

[0115] FIGS. 14A and 14B are examples of the current sensor 10 in which the magnetoelectric conversion elements are arranged at positions for detecting the magnetic field in the X-axis direction. FIG. 14A shows the internal configuration of the semiconductor package that functions as the current sensor 10 according to a modification of the embodiment shown in FIG. 13A. FIG. 14A is a schematic plan view seen from the ceiling surface side (Z-axis direction) of the current sensor 10 according to a modification of the embodiment shown in FIG. 13A. FIG. 14B is a cross-sectional view taken along line A-A of the current sensor 10 shown in FIG. 14A. In the current sensor 10 according to a modification of the embodiment shown in FIG. 13A, the magnetoelectric conversion elements 20a and 20b are built in the chip that constitutes the signal processing IC 100.

[0116] In the fifth embodiment, an example in which the current sensor 10 includes two magnetoelectric conversion elements 20a and 20b will be described. However, the current sensor 10 only needs to include at least one magnetoelectric conversion element.

[0117] The sealing portion 130 seals the magnetoelectric conversion elements 20a and 20b, the conductor portion 141, the support portion 151, the signal processing IC 100, the wire 22, and the wire 108 with a molding resin. The molding resin may be composed of, for example, an epoxy-based thermosetting resin added with silica and may be formed into a semiconductor package by transfer molding.

[0118] FIG. 15 shows an example of an enlarged view of the surrounded portion indicated by reference numeral 300 shown in FIG. 13B. The conductor portion 141 includes a first corner portion 1401 between a first end face 141c on a side opposite to the side connected to the terminal portion 142 and a face 141b facing the signal processing IC 100, and a second corner portion 1402 between the first end face 141c and a first face 141a on a side opposite to a second face 141b facing the first face 100a of the signal processing IC 100.

[0119] The second corner portion 1402 is a chamfered surface. The area of the outer surface of the second corner portion 1402 is larger than the area of the outer surface of the first corner portion 1401. The area of the outer surface of the first corner portion 1401 is the area of the outer surface defined from the boundary between the second face 141b and the first corner portion 1401 to the boundary between the first end face 141c and the first corner portion 1401. The area of the outer surface of the second corner portion 1402 is the area of the outer surface defined from the boundary between the first end face 141c and the second corner portion 1402 to the boundary between the first face 141a and the second corner portion 1402. The first corner portion 1401 may be a substantially straight line along the X-axis direction. The area of the outer surface of the first corner portion 1401 may be substantially zero.

[0120] By chamfering the second corner portion 1402 in this way, it is possible to suppress the concentration of thermal stress in the vicinity of the corner portion, suppress the occurrence of cracks in the sealing portion 130, and improve the durability of the current sensor 10.

[0121] The chamfered shape of the second corner portion 1402 may be any shape and may be composed of a plurality of surfaces formed by combining a plurality of substantially flat surfaces. The chamfered shape may be composed of one surface of a substantially flat surface as shown in FIG. 16A, may be composed of one surface of an R surface (curved surface) as shown in FIG. 16B, or may be composed of two surfaces formed by combining two substantially flat surfaces as shown in FIG. 16C. When the second corner portion 1402 is an R surface as shown in FIG. 16B, the area of the outer surface of the second corner portion 1402 is the area of the curved surface portion. The boundaries between the first end surface 141c and the second corner portion 1402, and between the first surface 141a and the second corner portion 1402 are the portions where the curved surface starts, respectively.

[0122] Hereinafter, the reason why the concentration of thermal stress in the vicinity of the corner portion can be suppressed by chamfering the second corner portion 1402 will be described.

[0123] Here, in the durability test of the current sensor 10, there is a test for measuring the state of the current sensor 10 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 mold resin constituting the sealing portion 130. Therefore, a force acts on the lead frame 140 in a direction of shrinking more than the sealing portion 130. Therefore, the shrinking speed of the sealing portion 130 cannot catch up with the shrinking speed of the lead frame 140, and the sealing portion 130 is pulled by the lead frame 140. As a result, there is a possibility that cracks may occur in the sealing portion 130.

[0124] In the case of a structure where the lead frame 140 and the lead frame 150 overlap in the thickness direction, the distance between the ceiling surface (surface 130e) of the sealing portion 130 and the lead frame 140 becomes relatively short. That is, the mold resin between the ceiling surface of the sealing portion 130 and the lead frame 140 becomes thin. Alternatively, the distance between the bottom surface (surface 130f) of the sealing portion 130 and the lead frame 150 becomes relatively short. That is, the mold resin between the bottom surface of the sealing portion 130 and the lead frame 150 becomes thin. Therefore, cracks may occur between the ceiling 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.

[0125] In the case of a structure where the lead frame 140 and the lead frame 150 overlap in the thickness direction, within the sealing portion, the step formed by bending is preferably set to be half or more of the thickness of the lead frame 140 or the lead frame 150. Thereby, the accuracy of the bending process is improved. Also, it is not necessary to perform a bending process for providing a step on 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 short.

[0126] In FIGS. 13B and 13C, the conductor portion 141 has a step formed by bending within the sealing portion 130. That is, the conductor portion 141 has a physically continuous flat portion 143, a stepped portion 144, and a flat portion 145. Among the conductor portion 141, the flat portion 143 is the portion closest to the ceiling surface of the seal. Here, as shown in FIGS. 13B and 13C, the distance between the first surface 130e on the first surface 141a side of the conductor portion 141 in the sealing portion 130 and the first surface 141a of the conductor portion 141 is t1, the width in the X-axis direction intersecting the Y-axis direction along the first surface 141a of the conductor portion 141 of the flat portion 143 is l1, 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 among the widths in the X-axis direction along the first surface 100a of the signal processing IC 100, the portion facing the second surface 141b of the flat portion 143 is l2. In this case, l1 / t1 > l2 / t2 is satisfied. Or, in this case, the aspect ratio of the mold resin with the thickness of t1 is larger than the aspect ratio of the mold resin with the thickness of t2, and among the interfaces between the lead frame 140 subjected to bending and the sealing portion 130 within the sealing portion 130, the stress at the first corner portion 1401 closest to the surface of the sealing portion 130 becomes the maximum.

[0127] In the flat portion 143, when the length in the Y-axis direction along the first surface 141a of the conductor portion 141 is l1 and the portion facing the second surface 141b of the flat portion 143 among the widths in the Y-axis direction along the first surface 100a of the signal processing IC 100 is l2, and l1 / t1 > l2 / t2 is satisfied, among the interfaces between the lead frame 140 subjected to bending and the sealing portion 130 within the sealing portion 130, the stress at the first corner portion 1401 closest to the surface of the sealing portion 130 becomes the maximum.

[0128] FIG. 17A shows an example of the simulation result of thermal stress when the current sensor 10 is placed in an environment with a minimum temperature of -65 degrees required in the durability test in a structure where the second corner portion 1402 is not chamfered. FIG. 17B shows an example of the simulation result of thermal stress when the current sensor 10 is placed in an environment with a minimum temperature of -65 degrees required in the durability test in a structure where the second corner portion 1402 is chamfered. FIGS. 17A and 17B show plots of the contour lines of thermal stress. Comparing FIGS. 17A and 17B, it can be seen that in the vicinity of the second corner portion 1402, the contour lines of thermal stress shown in FIG. 17A are denser than those shown in FIG. 17B. That is, it can be seen that without chamfering, thermal stress is more likely to concentrate near the second corner portion 1402.

[0129] When the lead frame 140 on the current conductor side and the lead frame 150 on the signal terminal side are stacked in the thickness direction, the part where thermal stress is most likely to concentrate is the second corner portion 1402 at the tip 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 portion 1402, the concentration of thermal stress can be suppressed, and the durability of the current sensor 10 can be improved.

[0130] The mold resin constituting the sealing portion 130 contains a large amount of fillers. The mold resin contains fillers with a filler diameter (diameter) of 20 μm or more, and the filling rate of the fillers is 60% or more. The modal value of the diameter of the fillers contained in the mold resin is about 20 μm. And when there are spheres with a diameter of about 20 μm in three dimensions, when viewed on the line segment of the chamfered portion, the dimension decreases to one dimension, so the filler diameter is about 15 μm (20 μm × (√3 / 2) 2 ) or so.

[0131] Here, when a minute crack occurs from a location where the equivalent stress is large, in order to suppress the crack propagation, it is important to increase the toughness of that location. When peeling occurs at the interface between the filler and the base material in the mold resin, since the energy of peeling is high, including the filler can increase the toughness against cracks in the base material such as epoxy, which is a brittle material. Therefore, it is preferable that an interface between the filler and the base material exists in the chamfered region where stress concentrates. That is, when the filler exists on the surface of the conductor portion 141, it is difficult for the filler to peel from the surface of the conductor portion 141, and cracks are less likely to occur in the sealing portion 130. Therefore, if the width of the chamfered surface is equal to or greater than the filler diameter, the probability that the filler exists in the chamfered portion becomes very high, and cracks are less likely to occur in the sealing portion 130.

[0132] As described above, the mold 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 viewed on the line segment of the chamfered portion, since the dimension decreases to one dimension, the filler diameter is about 15 μm. Considering that the filling rate of the filler is 60% or more, when the area is larger than 15 μm × 0.4 / 0.6 = 10 μm, the interface between the filler and the base material exists in the chamfered region with a probability higher than 60%. Therefore, it is preferable to ensure that the length of the side of the chamfered surface is 10 μm or more, preferably 15 μm or more, which is the one-dimensional filler diameter.

[0133] FIGS. 16A, 16B, and 16C show an example of the chamfered shape of the second corner portion 1402. Let the width in the first direction Y-axis when the second corner portion 1402 is projected in the Z-axis direction be width w1, and let the width in the Z-axis direction along the first end face 1412c when the second corner portion 1402 is projected in the Y-axis direction along the first face 141a of the conductor portion 141 be width w2. In this case, either one of the width w1 and the width w2 is larger than 15 μm and shorter than the thickness of the conductor portion 141. Thereby, as described above, the possibility that the filler exists in the chamfered portion can be increased. Thereby, the initial propagation of the crack can be suppressed, and the reliability of the current sensor 10 can be improved.

[0134] According to the current sensor 10 according to the fifth embodiment, an interface between the filler and the base material can be easily formed near the corner where thermal stress concentrates, the initial propagation of cracks can be suppressed, and the reliability of the current sensor 10 can be improved.

[0135] In the above embodiment, the form in which the lead frame 140 is bent has been described. However, the lead frame 150 may be bent instead of the lead frame 140.

[0136] FIG. 18A is a cross-sectional view of the current sensor 10 as viewed from the X-axis direction. FIG. 18B is a cross-sectional view of the current sensor 10 as viewed from the Y-axis direction.

[0137] The current sensor 10 according to the sixth embodiment is different from the current sensor 10 according to the fifth embodiment in that the lead frame 150 is bent instead of the lead frame 140, and the fourth corner 1504 of the support portion 151 is chamfered instead of the second corner 1401 of the conductor portion 141.

[0138] The support portion 151 is bent and 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. The support portion 151 may be bent and connected to the terminal portion 152 such that the surface of the portion of the first surface 151a of the support portion 151 that is connected to the terminal portion 152 is at least half the thickness of the support portion 151 and approaches the first surface 130e on the first surface 141a side of the conductor portion 141 in the sealing portion 130, compared to the surface of the first surface 151a of the support portion 151 that supports the signal processing IC 100.

[0139] The pair of terminals 142a and 142b protrude from the side surface 130a to the negative side in the Y-axis direction, and are further bent to 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 are further bent to the negative side in the Z-axis direction.

[0140] When current to be measured flows through the lead frame 140, heat generation occurs according to the electrical resistance. Therefore, it is preferable to reduce the electrical resistance by increasing the plate thickness or the like. On the other hand, when bending is performed on the lead frame, a step of any size can be formed regardless of the plate thickness. Therefore, even if the lead frame 150 uses a thin lead frame to reduce the material used, a desired step can be formed. As a result, the lead frame 150 may be thinner than the lead frame 140.

[0141] 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 becomes relatively short. That is, the molding resin between the bottom surface of the sealing portion 130 and the lead frame 150 becomes thin. Therefore, there is a possibility that cracks may occur between the bottom surface of the sealing portion 130 and the lead frame 150.

[0142] 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 set to be half or more of the thickness of the lead frame 140 or the lead frame 150. Thereby, the accuracy of the bending process is improved. In addition, it is not necessary to perform a bending process for providing a step in 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 tends to be short.

[0143] In FIGS. 6A and 6B, the support portion 151 has a step formed by bending within the sealing portion 130. That is, the support portion 151 has a physically continuous flat portion 153, a stepped portion 154, and a flat portion 155. Among the support portions 151, the flat portion 153 is the portion closest to the bottom surface of the seal. Here, as shown in FIGS. 18A and 18B, 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 in the X-axis direction along the second surface 151b of the support portion 151 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 among the widths in the X-axis direction along the first surface 100a of the signal processing IC 100, the width of the portion facing the second surface 141b of the conductor portion 141 is l2. In this case, l3 / t3 > l2 / t2 is satisfied. In this case, the aspect ratio of the mold resin with a thickness of t3 becomes larger than the aspect ratio of the mold resin with a thickness of t2, and among the interfaces between the lead frame 150 subjected to bending and the sealing portion 130 within the sealing portion 130, the stress at the fourth corner portion 1504 closest to the surface of the sealing portion 130 becomes the maximum.

[0144] In the flat portion 153, when the length in the Y-axis direction along the second surface 151b of the support portion 151 is l1 and the width of the portion facing the second surface 141b of the conductor portion 141 among the widths in the Y-axis direction along the first surface 100a of the signal processing IC 100 is l2, and l1 / t1 > l2 / t2 is satisfied, among the interfaces between the lead frame 140 subjected to bending and the sealing portion 130 within the sealing portion 130, the stress at the first corner portion 1401 closest to the surface of the sealing portion 130 becomes the maximum.

[0145] FIG. 19 shows an example of an enlarged view of the surrounded portion indicated by reference numeral 400 shown in FIG. 18A. The support portion 151 has a third corner portion 1503 between the second end surface 151c on the side opposite to the side connected to the terminal portion 152 and the first surface 151a of the support portion 151 that supports the signal processing IC 100, and a fourth corner portion 1504 between the second end surface 151c and the second surface 151b on the side opposite to the first surface 151a of the support portion 151.

[0146] 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 surface 151a and the third corner portion 1503 to the boundary between the second end surface 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 surface 151c and the fourth corner portion 1504 to the boundary between the second surface 151b and the fourth corner portion 1504. The area of the outer surface of the third corner portion 1503 can be substantially zero.

[0147] As described above, the stress of the fourth corner portion 1504 closest to the surface of the sealing portion 130 becomes the maximum. Therefore, the fourth corner portion 1504 is chamfered. That is, the area of the outer surface of the fourth corner portion 1504 is larger than the area of the outer surface of the third corner portion 1503. In this way, by chamfering the fourth corner portion 1504, the concentration of thermal stress in the vicinity of 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.

[0148] FIG. 20 shows an example of the chamfered shape of the fourth corner portion 1504. When the fourth corner portion 1504 is projected in the Z-axis direction along the second end surface 151c, the width in the direction along the second surface 151b of the support portion 151 is defined as w3, and when the fourth corner portion 1504 is projected in the Y-axis direction along the second surface 151b of the support portion 151, the width in the Z-axis direction along the second end surface 151c is defined as w4. In this case, either one of the width w3 and the width w4 is larger than 15 μm and shorter than the thickness of the support portion 151. Thereby, as described above, the possibility that a filler exists in the chamfered portion can be increased. Thereby, the initial progress of cracks can be suppressed, and the reliability of the current sensor 10 can be improved.

[0149] As described above, the present invention has been described using embodiments, but the technical scope of the present invention is not limited to the scope described in the above embodiments. It is obvious to those skilled in the art that various changes or improvements can be made to the above embodiments. It is clear from the description of the claims that forms with such changes or improvements can also be included in the technical scope of the present invention.

[0150] In the claims, the specification, and the drawings, the execution order of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown is not explicitly indicated as "earlier" or "preceding" etc. in particular, and it should be noted that it can be realized in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flows in the claims, the specification, and the drawings, even if explanations are made using "first," "next," etc. for convenience, it does not mean that it is essential to implement in this order. (Other possible items) (Item 1) 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, wherein a measured 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 the second surface side opposite to the first surface of the conductor portion, having a circuit surface facing the at least one magnetoelectric conversion element, and processing a signal output from the at least one magnetoelectric conversion element, A sealing portion for sealing the at least one magnetoelectric conversion element, the conductor portion, and the signal processing IC Comprising, The conductor portion has a first corner between a first end face on a side opposite to the side connected to the first terminal portion and a second face facing the signal processing IC, and a second corner between the first end face and a first face on a side opposite to the second face facing the signal processing IC, An area of an outer surface of the first corner is larger than an area of an outer surface of the second corner, a current sensor. (Item 2) The first corner is a chamfered surface, the current sensor according to item 1. (Item 3) Either a width in a direction along the second face of the conductor portion when the first corner is projected in a direction along the first end face, or a width in a direction along the first end face when the first corner is projected in a direction along the second face of the conductor portion is larger than 15 μm and shorter than a thickness of the conductor portion, the current sensor according to item 1. (Item 4) The width of the conductor part in the direction along the second surface when the first corner part is projected in the direction along the first end surface is longer than the width in the direction along the first end surface when the first corner part is projected in the direction along the second surface of the conductor part, the current sensor according to Item 1. (Item 5) The conductor part a first part connected to the first terminal part; a second part disposed opposite to the circuit surface of the signal processing IC and shifted from the first part in a direction away from the circuit surface of the signal processing IC in the thickness direction and connected to the first part and has The second part has a third corner part between a second end surface on the side connected to the first part and a first surface on the side opposite to the second surface facing the circuit surface of the signal processing IC. The area of the outer surface of the third corner part is larger than the area of the outer surface of the fourth corner part between the second end surface of the second part and the first surface on the same side as the first surface of the first part of the second part, the current sensor according to Item 1. (Item 6) The third corner part is a chamfered surface, the current sensor according to Item 5. (Item 7) Either the width in the direction along the first surface on the side opposite to the second surface of the conductor part when the third corner part is projected in the direction along the second end surface or the width in the direction along the second end surface when the third corner part is projected in the direction along the first surface of the conductor part is larger than 15 μm and shorter than the thickness of the conductor part, the current sensor according to Item 5. (Item 8) The shift amount of the second part with respect to the first part is 0.6 times or less of the thickness of the conductor part, the current sensor according to Item 5. (Item 9) The second end surface of the second part has a shearing surface, the current sensor according to Item 5. (Item 10) A second terminal portion that is disposed opposite to the first terminal portion with the signal processing IC therebetween in a plan view and is electrically connected to the signal processing IC, and a support portion that supports a surface of the signal processing IC opposite to the circuit surface side of the conductor portion with a first surface, further comprising a second lead frame that is electrically insulated from the first lead frame, The first portion has a fifth corner between a third end surface on a side where the second portion is connected and a second surface on the same side as the second surface of the second portion, The current sensor according to item 5, wherein an area of an outer surface of the fifth corner is larger than an area of an outer surface of a sixth corner between the third end surface of the first portion and the second surface of the second portion. (Item 11) The current sensor according to item 10, wherein the fifth corner is a chamfered surface. (Item 12) The current sensor according to item 10, wherein either a width in a direction along the second surface of the first portion when the fifth corner is projected in a direction along the third end surface, or a width in a direction along the third end surface when the fifth corner is projected in a direction along the second surface of the first portion is larger than 15 μm and shorter than a thickness of the conductor portion. (Item 13) The support portion has a seventh corner between the first surface that supports the signal processing IC and a fourth end surface on the first terminal portion side, and an eighth corner between the second surface opposite to the first surface that supports the signal processing IC and the fourth end surface, The current sensor according to item 10, wherein an area of an outer surface of the seventh corner is larger than an area of an outer surface of the eighth corner. (Item 14) The sealing portion is made of a molding resin, the molding resin contains a filler having a diameter of 20 μm or more, and a filling rate of the filler is 60% or more. The current sensor according to any one of items 3, 7, and 11. (Item 15) The at least one magnetoelectric conversion element protrudes from the circuit surface to a position overlapping the conductor portion when viewed from a direction intersecting the thickness direction of the at least one magnetoelectric conversion element. The current sensor according to item 1. (Item 16) The current sensor according to item 1, wherein the at least one magnetoelectric conversion element is formed on a chip different from the chip constituting the signal processing IC. (Item 17) The current sensor according to item 1, wherein the at least one magnetoelectric conversion element is built in the chip constituting the signal processing IC. (Item 18) The conductor portion has at least one slit portion, The current sensor according to item 1, wherein the at least one magnetoelectric conversion element is respectively disposed within the at least one slit portion in a plan view, and is at least partially surrounded by the conductor portion. (Item 19) The current sensor according to item 18, wherein the at least one magnetoelectric conversion element is fixed to the circuit surface by die bonding respectively within the at least one slit portion in a plan view, and is electrically connected to the signal processing IC by wire bonding. (Item 20) The current sensor according to item 19, wherein the magnetosensitive surface of the at least one magnetoelectric conversion element is disposed at a position overlapping with the side surface provided with the at least one slit of the conductor portion when viewed from a direction intersecting the thickness direction of the at least one magnetoelectric conversion element. (Item 21) The current sensor according to item 1, wherein the at least one magnetoelectric conversion element is a Hall element that detects a longitudinal magnetic field in the thickness direction of the conductor portion. (Item 22) The current sensor according to item 1, wherein the at least one magnetoelectric conversion element is a magnetoresistive element that detects a transverse magnetic field in a direction along the second surface of the conductor portion. (Item 23) 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, wherein a measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion. It is disposed on the second surface side opposite to the first surface of the conductor portion, has a circuit surface facing the second surface, and is a signal processing IC that processes a signal output from the at least one magnetoelectric conversion element. A sealing portion that seals the at least one magnetoelectric conversion element, the conductor portion, and the signal processing IC Comprising The conductor portion A first portion connected to the first terminal portion It is disposed opposite to the circuit surface of the signal processing IC, and in the thickness direction, in a direction away from the circuit surface of the signal processing IC, it is shifted with respect to the first portion and connected to the first portion. A second portion Having The second portion has a third corner portion between a second end surface on the side connected to the first portion and a first surface on the side opposite to 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 between the second end surface of the second portion and a first surface on the same side as the first surface of the first portion of the second portion. Current sensor. (Item 24) The second end surface of the second portion has a shear surface. The current sensor according to item 23. (Item 25) At least one magnetoelectric conversion element Including a first terminal portion and a conductor portion connected to the first terminal portion, and a first lead frame through which a measurement current measured by the at least one magnetoelectric conversion element flows through the first terminal portion and the conductor portion. It has a circuit surface on which the at least one magnetoelectric conversion element is disposed, and is a signal processing IC that processes a signal output from the at least one magnetoelectric conversion element. In a plan view, it includes a second terminal portion disposed opposite to the first terminal portion with the signal processing IC interposed therebetween and electrically connected to the signal processing IC, and a support portion that supports the signal processing IC on the first surface. A second lead frame that is electrically insulated from the first lead frame. A sealing portion that seals the at least one magnetoelectric conversion element, the conductor portion, the signal processing IC, and the support portion and includes The conductor portion is on the side of the first terminal portion with respect to the signal processing IC in a plan view, faces the second terminal portion side, has a first shear surface that is a step or an end surface having a shear surface, and among the corners of the first shear surface, the area of the outer surface of the fifth corner portion close to the second surface on the opposite side of the first surface of the support portion is larger than the area of the outer surface of the sixth corner portion far from the second surface. Current sensor (Item 26) At least one magnetoelectric conversion element, and A first lead frame including a first terminal portion and a conductor portion connected to the first terminal portion, wherein the 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 disposed opposite to the first terminal portion with the signal processing IC interposed therebetween in a plan view and electrically connected to the signal processing IC, and a support portion that supports the signal processing IC on a first surface, and being electrically insulated from the first lead frame A sealing portion that seals the at least one magnetoelectric conversion element, the conductor portion, the signal processing IC, and the support portion and includes The support portion has a seventh corner portion between the first surface that supports the signal processing IC and a second end surface on the first terminal portion side, and an eighth corner portion between the second surface opposite to the first surface that supports the signal processing IC and the second end surface The area of the outer surface of the seventh corner portion is larger than the area of the outer surface of the eighth corner portion. Current sensor (Other possible items) (Item 1) At least one magnetoelectric conversion portion, and A first lead frame including a first terminal portion and a conductor portion connected to the first terminal portion, wherein the measurement current measured by the at least one magnetoelectric conversion portion flows through the first terminal portion and the conductor portion A signal processing unit disposed on the second surface side opposite to the first surface of the conductor unit, having a circuit surface facing the second surface of the conductor unit, with the at least one magnetoelectric conversion unit disposed on the circuit surface, and processing a signal output from the at least one magnetoelectric conversion unit. A second lead frame including a support unit that supports a support surface opposite to the circuit surface of the signal processing unit with a first surface, and a second terminal unit that is connected to the support unit and outputs a signal from the signal processing unit. A sealing unit that seals the at least one magnetoelectric conversion unit, the conductor unit, the signal processing unit, and the support unit. The conductor unit has a first corner between a first end surface on a side opposite to the side connected to the first terminal unit and a second surface facing the signal processing unit, and a second corner between the first end surface and the first surface of the conductor unit. The support unit has a third corner between a second end surface on a side opposite to the side connected to the second terminal unit and the first surface of the support unit that supports the signal processing unit, and a fourth corner between the second end surface and a second surface opposite to the first surface of the support unit. An area of an outer surface of the second corner is larger than an area of an outer surface of the first corner, or an area of an outer surface of the fourth corner is larger than an area of an outer surface of the third corner. A current sensor. (Item 2) The area of the outer surface of the second corner is larger than the area of the outer surface of the first corner, and the conductor unit is bent so as to approach the second surface on the second surface side of the support unit in the sealing unit and is connected to the first terminal unit. The current sensor according to Item 1. (Item 3) The area of the outer surface of the second corner is larger than the area of the outer surface of the first corner, and the conductor unit is bent so as to approach the second surface on the second surface side of the support unit in the sealing unit and is connected to the first terminal unit, where a surface of a portion of the second surface of the conductor unit that is connected to the first terminal unit is at least half of the thickness of the conductor unit, compared to a surface of the second surface of the conductor unit that faces the circuit surface of the signal processing unit. The current sensor according to Item 1. (Item 4) 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 so as to approach the first surface on the first surface side of the conductor portion in the sealing portion and is connected to the second terminal portion. The current sensor according to item 1. (Item 5) 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 has a surface area of the support portion that is half or more of the thickness of the support portion on the portion connected to the second terminal portion of the first surface of the support portion rather than the surface supporting the signal processing portion on the first surface of the support portion. The current sensor according to item 1, which is bent so as to approach the first surface on the first surface side of the conductor portion in the sealing portion and is connected to the second terminal portion. (Item 6) 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. The current sensor according to item 1. (Item 7) 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. The current sensor according to item 1. (Item 8) At a predetermined minimum temperature, the linear expansion coefficient of the first lead frame or the second lead frame is larger than the linear expansion coefficient of the mold resin constituting the sealing portion. The current sensor according to item 1. (Item 9) When 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, either the width in the direction along the first surface of the conductor portion when the second corner portion is projected in the direction along the first end surface, or the width in the direction along the first end surface when the second corner portion is 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. The current sensor according to item 1. (Item 10) The sealing portion is made 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. The current sensor according to item 9. (Item 11) 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 either the width in the direction along the second surface of the support portion when the fourth corner portion is projected in the direction along the second end surface, or the width in the direction along the second end surface when the fourth corner portion is 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. The current sensor according to item 1. (Item 12) The sealing portion is made 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. The current sensor according to item 11. (Item 13) The conductor portion is covered with the mold resin that constitutes the sealing portion and has no interface with anything other than the mold resin. The current sensor according to item 1. (Item 14) The first lead frame is thicker than the second lead frame. The current sensor according to item 1. (Item 15) The first terminal portion protrudes from the first side surface of the sealing portion, and the second terminal portion protrudes from the second side surface that faces 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. When the distance between the first surface on the first surface side of the conductor portion in the sealing portion and the first surface of the conductor portion is t1, the width in the second direction intersecting the first direction along the first surface of the portion of the conductor portion facing the signal processing portion is l1, the distance between the second surface of the conductor portion and the circuit surface of the signal processing portion is t2, and the width in the second direction along the circuit surface of the signal processing portion is l2, l1 / t1 > l2 / t2 is satisfied. The current sensor according to item 1. (Item 16) The first terminal portion protrudes from the first side surface of the sealing portion, and the second terminal portion protrudes from the second side surface that faces 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. When the distance between the second surface on the second surface side of the support portion in the sealing portion and the second surface of the support portion is t3, the width in the second direction intersecting the first direction along the second surface of the support portion of the portion supporting the signal processing portion in the support portion is l3, the distance between the second surface of the conductor portion and the circuit surface of the signal processing portion is t2, and the width in the second direction along the circuit surface of the signal processing portion is l2, the current sensor according to item 1, which satisfies l3 / t3 > l2 / t2. (Item 17) The signal processing portion is an IC chip. The at least one magnetoelectric conversion portion is a magnetoelectric conversion element separate from the IC chip. The magnetosensing surface of the magnetoelectric conversion element protrudes from the surface facing the conductor portion of the IC chip. The current sensor according to any one of items 1 to 16. (Item 18) The signal processing portion is an IC chip. The magnetoelectric conversion portion is built in the IC chip. The magnetosensing surface of the magnetoelectric conversion portion does not protrude from the surface facing the conductor portion of the IC chip. The current sensor according to any one of items 1 to 16.

Explanation of Signs

[0151] 10 Current sensor 20a, 20b Magnetoelectric conversion element 22, 22a, 22b, 108 Wire 100 Signal processing IC 130 Sealing portion 140, 150 Lead frame 141 Conductor portion 141a, 141B Slit portion 142 Terminal portion 142a, 142b, 152a Terminal 144, 155 Step portion 152 Terminal portion 151, 154 Support portion 155 Step portion 1401 First corner portion 1402 Second corner portion 1403, 1503 The 3rd corner part 1404, 1504 The 4th corner part 1405 The 5th corner part 1406 The 6th corner part 1411 The 1st part 1412 The 2nd part 1501 The 7th corner part 1502 The 8th corner part

Claims

1. 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, wherein a measurement current measured by the at least one magneto-electric transducer flows through the first terminal portion and the conductor portion; a signal processing IC disposed on a second surface side of the conductor portion opposite to the first surface, on which the at least one magneto-electric transducer is disposed, the signal processing IC having a circuit surface facing the second surface, and processing a signal output from the at least one magneto-electric transducer; a sealing portion that seals the at least one magnetoelectric conversion element, the conductor portion, and the signal processing IC; Equipped with the conductor portion has a first corner portion between a first end face opposite to a side connected to the first terminal portion and a second face facing the signal processing IC, and a second corner portion between the first end face and a first face opposite to the second face facing the signal processing IC, A current sensor, wherein an area of ​​an outer surface of the first corner portion is greater than an area of ​​an outer surface of the second corner portion.

2. The current sensor of claim 1 , wherein the first corner is a chamfered surface.

3. 2. The current sensor of claim 1, wherein either a width of the conductor portion in a direction along the second surface when the first corner portion is projected in a direction along the first end surface, or a width of the conductor portion in a direction along the first end surface when the first corner portion is 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. 2. The current sensor of 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 conductor portion is a first portion connected to the first terminal portion; a second portion disposed opposite to the circuit surface of the signal processing IC, shifted in a thickness direction relative to the first portion in a direction away from the circuit surface of the signal processing IC, and connected to the first portion; having the second portion has a third corner portion between a second end surface connected to the first portion and a first surface opposite to a second surface facing the circuit surface of the signal processing IC, The current sensor of claim 1 , wherein an area of ​​an outer surface of the third corner portion is greater than an area of ​​an outer surface of a fourth corner portion between the second end face of the second portion and a first face of the first portion on the same side as the first face of the second portion.

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

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

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

9. The current sensor of claim 5 , wherein the second end surface of the second portion comprises a shear surface.

10. a second terminal portion disposed opposite the first terminal portion across the signal processing IC in a plan view and electrically connected to the signal processing IC, and a support portion supporting a surface of the signal processing IC opposite the circuit surface on the conductor portion side with a first surface, the second lead frame being electrically insulated from the first lead frame; the first portion has a fifth corner between a third end surface on a side to which the second portion is connected and a second surface on the same side as the second surface of the second portion, The current sensor according to claim 5 , wherein an area of ​​an outer surface of the fifth corner portion is larger than an area of ​​an outer surface of a sixth corner portion between the third end surface of the first portion and the second surface of the second portion.

11. The current sensor of claim 10 , wherein the fifth corner is a chamfered surface.

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

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

14. 12. The current sensor according to claim 3, wherein the sealing portion is made of a mold resin, the mold resin contains a filler having a diameter of 20 um or more, and a filling rate of the filler is 60% or more.

15. The current sensor according to claim 1 , wherein the at least one magnetoelectric transducer protrudes from the circuit surface to a position overlapping the conductor portion when viewed in a direction intersecting a thickness direction of the at least one magnetoelectric transducer.

16. 2. The current sensor according to claim 1, wherein the at least one magnetoelectric conversion element is configured on a chip separate from a chip that configures the signal processing IC.

17. The current sensor according to claim 1 , wherein the at least one magnetoelectric conversion element is built in a chip constituting the signal processing IC.

18. The conductor portion has at least one slit portion, The current sensor according to claim 1 , wherein the at least one magnetoelectric transducer is disposed in the at least one slit portion in a plan view, and is at least partially surrounded by the conductor portion.

19. 19. The current sensor according to claim 18, wherein the at least one magnetoelectric conversion element is fixed to the circuit surface by die bonding within the at least one slit portion in a plan view, and is electrically connected to the signal processing IC by wire bonding.

20. The current sensor of claim 19, wherein the magnetic sensitive surface of the at least one magnetoelectric conversion element is positioned at a position overlapping with a side of the conductor portion on which the at least one slit is provided, when viewed from a direction intersecting the thickness direction of the at least one magnetoelectric conversion element.

21. The current sensor according to claim 1 , wherein the at least one magnetoelectric 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 magnetoelectric conversion element is a magnetoresistance element that detects a transverse magnetic field in a direction along the second surface of the conductor portion.

23. 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, wherein a measurement current measured by the at least one magneto-electric transducer flows through the first terminal portion and the conductor portion; a signal processing IC disposed on a second surface side of the conductor portion opposite to the first surface, on which the at least one magneto-electric transducer is disposed, the signal processing IC having a circuit surface facing the second surface, and processing a signal output from the at least one magneto-electric transducer; a sealing portion that seals the at least one magnetoelectric conversion element, the conductor portion, and the signal processing IC; Equipped with The conductor portion is a first portion connected to the first terminal portion; a second portion disposed opposite to the circuit surface of the signal processing IC, shifted in a thickness direction relative to the first portion in a direction away from the circuit surface of the signal processing IC, and connected to the first portion; having the second portion has a third corner portion between a second end surface connected to the first portion and a first surface opposite to a second surface facing the circuit surface of the signal processing IC, A current sensor, wherein the area of ​​the outer surface of the third corner portion is greater than the area of ​​the outer surface of a fourth corner portion between the second end face of the second portion and a first face of the first portion on the same side as the first face of the second portion.

24. The current sensor of claim 23 , wherein the second end surface of the second portion comprises a shear surface.

25. 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, wherein a measurement current measured by the at least one magneto-electric transducer flows through the first terminal portion and the conductor portion; a signal processing IC having a circuit surface on which the at least one magneto-electric transducer is disposed, the signal processing IC processing a signal output from the at least one magneto-electric transducer; a second lead frame including a second terminal portion electrically connected to the signal processing IC and a support portion supporting the signal processing IC on a first surface, the second lead frame being disposed opposite the first terminal portion across the signal processing IC in a plan view, and the second lead frame being electrically insulated from the first lead frame; a sealing portion that seals the at least one magnetoelectric conversion element, the conductor portion, the signal processing IC, and the support portion; Equipped with A current sensor, wherein the conductor portion is located on the first terminal portion side of the signal processing IC in a planar view, faces the second terminal portion side, and has a first shear surface which is a step or end face having a shear surface, and among the corners of the first shear surface, an outer surface area of ​​a fifth corner which is closer to a second surface opposite the first surface of the support portion is larger than an outer surface area of ​​a sixth corner which is farther from the second surface.

26. 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, wherein a measurement current measured by the at least one magneto-electric transducer flows through the first terminal portion and the conductor portion; a signal processing IC having a circuit surface on which the at least one magneto-electric transducer is disposed, the signal processing IC processing a signal output from the at least one magneto-electric transducer; a second lead frame including a second terminal portion electrically connected to the signal processing IC and a support portion supporting the signal processing IC on a first surface, the second lead frame being disposed opposite the first terminal portion across the signal processing IC in a plan view, and the second lead frame being electrically insulated from the first lead frame; a sealing portion that seals the at least one magnetoelectric conversion element, the conductor portion, the signal processing IC, and the support portion; Equipped with the support portion has a seventh corner portion between the first surface supporting the signal processing IC and a second end surface on the first terminal portion side, and an eighth corner portion between a second surface opposite to the first surface supporting the signal processing IC and the second end surface, A current sensor, wherein an area of ​​an outer surface of the seventh corner is greater than an area of ​​an outer surface of the eighth corner.

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