Current sensor

Abstract

The current sensor comprises at least one magnetoelectric conversion unit, a first lead frame including a first terminal portion and a conductor portion, a signal processing IC, a second lead frame including a second terminal portion, and a sealing portion that seals the at least one magnetoelectric conversion unit, the conductor portion, the signal processing IC, and a portion of the second lead frame with molded resin. The shorter of the distances from the first side surface of the sealing portion where the first terminal portion is exposed to the holding portion or the signal processing IC is T ds When the relative permittivity of the mold resin is ε, 523 × T ds -1 ×ε 0.08 Satisfy <400.

Description

[Technical Field]

[0001] This invention relates to a current sensor. [Background technology]

[0002] Patent Document 1 discloses a semiconductor device in which, in order to ensure the minimum creepage distance, the suspension leads are not exposed on the resin-sealed wall surface at corners where suspension leads are not located. [Prior art document] [Patent] [Patent Document 1] Japanese Unexamined Patent Publication No. 2016-152298 [Overview of the Initiative] [Problems that the invention aims to solve]

[0003] There is a need to more reliably ensure the insulation performance of current sensors, which measure current values ​​by detecting changes in the magnetic field generated in a conductor due to the flow of electric current using a magnetoelectric conversion element. [Means for solving the problem]

[0004] A current sensor according to one aspect of the present invention may include at least one magnetoelectric conversion unit. The current sensor may include a first lead frame, which includes a first terminal portion and a conductor portion connected to the first terminal portion, through which a measured current measured by the at least one magnetoelectric conversion unit flows. The current sensor may include a signal processing IC disposed on a second surface side opposite to the first surface of the conductor portion, which has a circuit surface, the at least one magnetoelectric conversion unit is disposed on the circuit surface, and the signal processing IC processes the signal output from the at least one magnetoelectric conversion unit. The current sensor may include a second lead frame, which includes a second terminal portion that outputs a signal from the signal processing IC. The current sensor may include a sealing portion that seals the at least one magnetoelectric conversion unit, the conductor portion, the signal processing IC, and a part of the second lead frame with a molding resin. The shortest distance among the distances from the first side surface of the sealing portion where the first terminal portion is exposed to the second lead frame or the signal processing IC is T ds When the relative permittivity of the mold resin is ε, 523 × T ds -1 ×ε 0.08 The condition <400 may be satisfied.

[0005] In the current sensor, T ds It is fine if it is 1.6 mm or larger.

[0006] In the signal processing IC, the second surface of the conductor portion is the first surface of the signal processing IC, and the surface of the signal processing IC opposite to the first surface is the second surface, and the second lead frame may have a holding portion on the second surface side of the signal processing IC for holding the signal processing IC.

[0007] The shortest distance Tds may be the distance between the first side surface of the sealing portion and the holding portion.

[0008] A current sensor according to one 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 measured current measured by the at least one magnetoelectric conversion unit flows through the first terminal portion and the conductor portion. The current sensor may include a signal processing IC disposed on a second surface side opposite to a first surface of the conductor portion, the signal processing IC having a circuit surface, the at least one magnetoelectric conversion unit being disposed on the circuit surface, and the signal processing IC processing a signal output from the at least one magnetoelectric conversion unit. The current sensor may include a second lead frame including a second terminal portion that outputs a signal from the signal processing IC. The current sensor may include a sealing portion that seals a part of the at least one magnetoelectric conversion unit, the conductor portion, the signal processing IC, and the second lead frame with a molding resin. In the signal processing IC, the surface on the second surface side of the conductor portion is defined as the first surface of the signal processing IC, the surface on the opposite side of the first surface of the signal processing IC is defined as the second surface, and in the sealing portion, the surface facing the first surface of the conductor portion is defined as the first surface of the sealing portion, the surface facing the second surface of the conductor portion is defined as the second surface of the sealing portion, and the surface on which the first terminal portion of the conductor portion is exposed is defined as the first side surface. The distance between the portion closest to the first side surface of the sealing portion among the second surface of the signal processing IC or the second surface of the conductor portion and the second surface of the sealing portion is T b , when the relative permittivity of the molding resin is ε, may satisfy 470×T b -1 ×ε 0.08 <400.

[0009] In the current sensor, T b may be 1.35 mm or more.

[0010] In the signal processing IC, the surface on the second surface side of the conductor portion is defined as the first surface of the signal processing IC, the surface on the opposite side of the first surface of the signal processing IC is defined as the second surface, and the second lead frame may have a holding portion that holds the signal processing IC on the second surface side of the signal processing IC.

[0011] In the current sensor, the height of the portion of the conductor that does not overlap with the signal processing IC in the thickness direction from the second surface of the sealing portion may be different from the height of the holding portion from the second surface of the sealing portion.

[0012] A current sensor according to one aspect of the present invention may include at least one magnetoelectric conversion unit. The current sensor may include a first lead frame that includes a first terminal portion and a conductor portion connected to the first terminal portion, through which a measured current measured by the at least one magnetoelectric conversion unit flows. The current sensor may include a signal processing IC disposed on a second surface side opposite to the first surface of the conductor portion, having a circuit surface, with the at least one magnetoelectric conversion unit disposed on the circuit surface, and processing the signal output from the at least one magnetoelectric conversion unit. The current sensor may include a second lead frame that includes a second terminal portion that outputs a signal from the signal processing IC. The current sensor may include a sealing portion that seals the at least one magnetoelectric conversion unit, the conductor portion, the signal processing IC, and a part of the second lead frame with a molding resin. In the sealing portion, the surface facing the first surface of the conductor portion is defined as the first surface of the sealing portion, and the surface on which another part of the second lead frame is exposed is defined as the second side surface. The distance between the portion of the first surface of the conductor portion closest to the second side surface of the sealing portion and the first surface of the sealing portion facing the first surface of the conductor portion is defined as T. t When the relative permittivity of the mold resin is ε, 280 × T t -0.2 ×ε 0.12 The condition <400 may be satisfied.

[0013] In the current sensor, the shortest distance among the distances from the first side surface where the first terminal portion of the sealing portion is exposed to the second lead frame or the signal processing IC is T ds In that case, 523 × T ds -1 ×ε 0.08 The value <400 may also be satisfied.

[0014] In the signal processing IC, the surface of the conductor portion facing the second surface is defined as the first surface of the signal processing IC, and the surface of the signal processing IC opposite to the first surface is defined as the second surface. In the sealing portion, the surface facing the first surface of the conductor portion is defined as the first surface of the sealing portion, the surface facing the second surface of the conductor portion is defined as the second surface of the sealing portion, and the surface on which the first terminal portion of the conductor portion is exposed is defined as the first side surface. The distance between the portion of the second surface of the signal processing IC closest to the first side surface of the sealing portion and the second surface of the sealing portion is defined as T. b In that case, 470 × T b -1 ×ε 0.08 The condition <400 may be further satisfied.

[0015] In the signal processing IC, the second surface side of the conductor portion is the first surface of the signal processing IC, and the surface opposite to the first surface of the signal processing IC is the second surface. In the sealing portion, the surface facing the first surface of the conductor portion is defined as the first surface of the sealing portion, the surface facing the second surface of the conductor portion is defined as the second surface of the sealing portion, and the surface on which the first terminal portion of the conductor portion is exposed is defined as the first side surface. The shortest distance among the distances from the first side surface of the sealing portion to the second lead frame or the signal processing IC is defined as T. ds The distance between the portion of the second surface of the signal processing IC closest to the first surface of the sealing portion and the second surface of the sealing portion is T. b In that case, 523 × T ds -1 ×ε 0.08 <400, and 470 × T b -1 ×ε 0.08 The condition <400 may be further satisfied.

[0016] In the signal processing IC, the second surface of the conductor portion is the first surface of the signal processing IC, and the surface of the signal processing IC opposite to the first surface is the second surface, and the second lead frame may have a holding portion on the second surface side of the signal processing IC for holding the signal processing IC.

[0017] In the sealing portion, the surface facing the first surface of the conductor portion is the first surface of the sealing portion, and the surface facing the second surface of the conductor portion is the second surface of the sealing portion. The conductor portion has a stepped portion, a first portion on the side of the first surface of the sealing portion connected via the stepped portion, and a second portion on the side of the second surface of the sealing portion, and the first portion may be connected to the first terminal portion.

[0018] In the current sensor, the first surface of the signal processing IC is the circuit surface, and the at least one magnetoelectric conversion element may be separate from the signal processing IC.

[0019] In the current sensor, the signal processing IC may incorporate the circuit plane and the at least one magnetoelectric conversion element.

[0020] In the current sensor, the at least one magnetoelectric conversion element may be a Hall element.

[0021] It should be noted that the above summary of the invention does not enumerate all of its features. Furthermore, subcombinations of these features may also constitute an invention. [Brief explanation of the drawing]

[0022] [Figure 1A] This is a schematic plan view of the current sensor according to this embodiment, as seen from the ceiling side (z-axis direction). [Figure 1B] Figure 1A is a cross-sectional view of the current sensor shown along line AA. [Figure 1C] This is a cross-sectional view along line AA of a first modified example of the current sensor according to this embodiment. [Figure 1D] This is a cross-sectional view along line AA of a second modified example of the current sensor according to this embodiment. [Figure 1E] This is a cross-sectional view along line AA of a third modified example of the current sensor according to this embodiment. [Figure 1F] This is a schematic plan view of a fourth modified example of the current sensor according to this embodiment, as seen from the ceiling side (z-axis direction). [Figure 1G]This is a cross-sectional view AA of a fourth modified example of the current sensor according to this embodiment. [Figure 2] This figure shows the results based on equation (2), which represents the relationship between the electric field E and the distance Tds on the surface of the sealing portion, and the results based on the finite element method. [Figure 3A] This figure shows an example of the distribution of the magnitude of the electric field E generated by partial discharge between the holding part and the conducting part when Tds = 0.6. [Figure 3B] This figure shows an example of the distribution of the magnitude of the electric field E generated by a partial discharge occurring between the holding part 151 and the conducting part 141 when Tds = 1.6 (mm). [Figure 4] This figure shows the results based on equation (2), which shows the relationship between the electric field E and the relative permittivity ε on the surface of the sealing part, and the results based on the finite element method, when C=523, x=-1, y=0.08, and Tds=0.6. [Figure 5] This figure shows the results based on equation (3), which shows the relationship between the electric field E and distance Tb on the surface of the sealing part, and the results based on the finite element method, when C=470, x=-1, and y=0.08. [Figure 6] This figure shows the results based on equation (3), which represents the relationship between the electric field E and the relative permittivity ε on the surface of the sealing portion, and the results based on the finite element method, when C=470, x=-1, y=0.08, and Tb=1.37 mm. [Figure 7A] This figure shows the distribution of the magnitude of the electric field generated between the holding part and the conducting part when C=470, x=-1, y=0.08, and Tb=1.37 mm, and ε=12. [Figure 7B] This figure shows the distribution of the magnitude of the electric field generated between the holding part and the conducting part when ε=2, given that C=470, x=-1, y=0.08, and Tb=1.37mm. [Figure 8] This figure shows the results based on equation (4), which shows the relationship between the electric field E and distance Tt on the surface of the sealing part, and the results based on the finite element method, when C=280, x=-0.2, and y=0.12. [Figure 9]This figure shows the results based on equation (4), which represents the relationship between the electric field E and the relative permittivity ε on the surface of the sealing portion, and the results based on the finite element method, when C=280, x=-0.2, y=0.12, and Tt=0.63 mm. [Figure 10] This figure shows the condition table for the sample created as an example. [Figure 11] This figure shows the surface discharge generation voltage for each of equations (2), (3), and (4) for each sample. [Modes for carrying out the invention]

[0023] The present invention will be described below through embodiments of the invention, but these embodiments are not intended to limit the invention as defined in the claims. Furthermore, not all combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0024] Figures 1A and 1B show the internal configuration of a semiconductor package that functions as a current sensor 10 according to this embodiment. Figure 1A is a schematic plan view of the current sensor 10 according to this embodiment, viewed from the top side (z-axis direction). Figure 1B is a cross-sectional view of the current sensor 10 shown in Figure 1A, along line AA.

[0025] In Figure 1A, the coordinate system is defined as follows: the x-axis is parallel to the plane of the paper and runs from bottom to top; the y-axis is parallel to the plane of the paper and runs from right to left; and the z-axis is perpendicular to the plane of the paper and runs from back to front. Any one of the x, y, or z axes is perpendicular to the other axes.

[0026] The current sensor 10 comprises 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.

[0027] 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, in a plan view, partially surrounds the magnetoelectric conversion elements 20a and 20b together with a part of the terminal portion 142. A measurement current flows through the terminal portion 142 and the conductor portion 141. The pair of terminals 142a and 142b are physically integral 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. The lead frame 140 does not need to be manufactured using a form in which multiple conductor portions 141 and terminal portions 142 are connected together; it may be manufactured using the form of individual metal parts.

[0028] The lead frame 150 includes a holding portion 151 and a terminal portion 152. The terminal portion 152 includes a plurality of terminals 152a. The holding portion 151 is sealed within the sealing portion 130 and holds the signal processing IC 100. The holding portion 151 holds the signal processing IC 100. The signal processing IC 100 may be fixed to the surface 151a of the holding portion 151 via an adhesive layer. The adhesive layer may be a die attach film.

[0029] When the lead frame 140 is composed of lead frames and the lead frame 140 and lead frame 150 are arranged overlapping in the thickness direction, a step may be provided in the thickness direction on at least one of the lead frame 140 and lead frame 150 to ensure insulation between the lead frame 140 and the lead frame 150 or the signal processing IC 100. For example, the holding portion 151 may include a stepped portion 155 that rises from the surface 151a supporting the signal processing IC 100 toward the conductor portion 141. The stepped portion 155 may be formed by recessing the holding portion 151 in the thickness direction (z-axis direction) toward the direction away from the conductor portion 141 (towards the bottom surface of the sealing portion 130). The stepped portion 155 may be formed by performing a half-through processing on the lead frame 150. Note that the stepped portion 155 is not required.

[0030] Multiple terminals 152a are physically integrated with the holding portion 151 and are exposed outside the sealing portion 130. The lead frame 150 is an example of a second lead frame. The lead frame 140 and lead frame 150 may be made of a conductive material mainly composed of copper.

[0031] Here, the x-axis is the direction along the planes of lead frames 140 and 150, and the direction in which the multiple terminals 152a are arranged. The y-axis is the direction along the planes of lead frames 140 and 150, and also the direction intersecting the x-axis. In a plan view, the y-axis is also the direction in which the multiple terminals 152a and the pair of terminals 142a and 142b extend. The z-axis is the direction intersecting the planes of lead frames 140 and 150, the direction intersecting the circuit plane (plane 100a) of the signal processing IC 100, and also the thickness direction of the sealing portion 130.

[0032] The pair of terminals 142a and 142b and the multiple terminals 152a are arranged facing each other via the signal processing IC 100 in a direction (y-axis direction) that intersects with the thickness direction (z-axis direction) of the signal processing IC 100. The pair of terminals 142a and 142b are exposed from the side surface 130a of the sealing portion 130. The multiple terminals 152a are exposed from the side surface 130b of the sealing portion 130, opposite to the side surface 130a.

[0033] The pair of terminals 142a and 142b may have portions that are separated from the side surface 130a of the sealing portion 130 and bent toward the bottom surface 130f of the sealing portion in the thickness direction. The multiple terminals 152a may have portions that are separated from the side surface 130b of the sealing portion and bent toward the bottom surface 130f of the sealing portion in the thickness direction. The bending direction of the pair of terminals 142a and 142b, and the multiple terminals 152a, may be toward the top surface 130e of the sealing portion 130 in the thickness direction, rather than toward the bottom surface 130f of the sealing portion 130.

[0034] The magnetoelectric conversion elements 20a and 20b are electrically connected to the signal processing IC 100 via a plurality of wires 22a and 22b. The magnetoelectric conversion elements 20a and 20b are configured separately from the signal processing IC 100 and output signals processed by the signal processing IC 100 to the signal processing IC 100. The signal processing IC 100 is electrically connected to a plurality of terminals 152a via wire 108. Wires 22a, 22b and wire 108 may be formed from a conductive material mainly composed of Au, Ag, Cu, or Al.

[0035] The magnetoelectric conversion elements 20a and 20b may protrude from the surface 100a of the signal processing IC 100 such that, in a side view, the magnetosensitive surfaces of the magnetoelectric conversion elements 20a and 20b overlap with the conductor portion 141. This can increase the sensitivity of the magnetoelectric conversion elements 20a and 20b.

[0036] The magnetoelectric conversion elements 20a and 20b detect a magnetic field in a specific direction that changes according to the measured current flowing through the conductor portion 141, and the signal processing IC 100 amplifies the signal according to the magnitude of the magnetic field and outputs the amplified signal via terminal 152a. The magnetoelectric conversion elements 20a and 20b are made of compound semiconductors formed on a GaAs substrate and may be chips cut into a square or rectangular shape when viewed from the z-axis direction.

[0037] The magnetoelectric conversion elements 20a and 20b may have a substrate made of silicon or a compound semiconductor and a magnetoelectric conversion unit 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 will be detected, for example, a transverse Hall element is suitable as the magnetoelectric conversion elements 20a and 20b. Furthermore, if the magnetoelectric conversion elements 20a and 20b are positioned to detect a magnetic field in any one axis direction on the xy-plane, for example, if they are positioned to detect a magnetic field in the x-axis direction, then a magnetoresistive element or a fluxgate element is suitable as the magnetoelectric conversion elements 20a and 20b. The magnetoresistive element may be, for example, a semiconductor magnetoresistive element (SMR), an anomalous magnetoresistive element (AMR), a giant magnetoresistive element (GMR), or a tunnel magnetoresistive element (TMR).

[0038] In this embodiment, the magnetoelectric conversion elements 20a and 20b are not built into the signal processing IC 100, but are installed on the circuit surface (surface 100a). That is, the current sensor 10 is not a monolithic structure, with the magnetoelectric conversion elements 20a and 20b and the signal processing IC 100 being separate components. However, the magnetoelectric conversion elements 20a and 20b may be configured as a monolithic structure built into the signal processing IC 100. Furthermore, in this embodiment, an example in which the current sensor 10 comprises two magnetoelectric conversion elements 20a and 20b is described. However, the current sensor 10 may have one or more magnetoelectric conversion elements.

[0039] The signal processing IC 100 is a large-scale integrated circuit (LSI). The signal processing IC 100 is a signal processing circuit made of a Si monolithic semiconductor formed on a Si substrate. The signal processing circuit processes output signals corresponding to the magnitude of the magnetic field output from the magnetoelectric conversion elements 20a and 20b. Based on the output signals, the signal processing circuit corrects the measured current flowing through the conductor part 141 and outputs an output signal indicating the corrected current value via terminal 152a. That is, the signal processing IC 100 and the lead frame 150 are electrically connected via wires or the like. Based on the difference between the output signals of the magnetoelectric conversion elements 20a and 20b, the signal processing circuit reduces the noise components contained in the output signals of the magnetoelectric conversion elements 20a and 20b, adds and amplifies the output signals of the magnetoelectric conversion elements 20a and 20b with the noise components reduced, calculates the current value of the measured current based on the amplified output signal, and outputs an output signal indicating the current value.

[0040] As shown in Figure 1B, the pair of terminals 142a, 142b and the multiple terminals 152a may protrude outward from different heights in the thickness direction of the sealing portion 130 on the opposing sides 130a and 130b of the sealing portion 130. The height of the conductor portion 141 from the bottom surface (surface 130f) of the sealing portion 130 in the portion that does not overlap with the signal processing IC 100 in the thickness direction (z-axis direction) is different from the height of the retaining portion 151 from the surface 130f of the sealing portion 130.

[0041] The height in the thickness direction (z-axis direction) of the sealing portion 130 on the same side 1521 of the terminals 152a at the point where it intersects with the side 130b of the sealing portion 130, and the height in the thickness direction (z-axis direction) of the sealing portion 130 on the same side 1421 of the terminals 142a and 142b at the point where it intersects with the side 130a of the sealing portion 130, on the same side 1421 as the side opposite to the terminals 100a of the signal processing IC 100, may be the same. Alternatively, the height in the thickness direction (z-axis direction) of the sealing portion 130 on the terminals 152a at the point where it intersects with the side 130b of the sealing portion 130 may be lower than the height in the thickness direction (z-axis direction) of the sealing portion 130 on the terminals 142a and 142b at the point where it intersects with the side 130a of the sealing portion 130.

[0042] In the current sensor shown in Figure 1B, the height of the surface 1521 of the multiple terminals 152a at the point where it intersects with the side surface 130b of the sealing portion 130, in the thickness direction (z-axis direction) of the sealing portion 130, is located below the height of the surface 1421 of the pair of terminals 142a and 142b at the point where it intersects with the side surface 130a of the sealing portion 130, in the thickness direction (z-axis direction) of the sealing portion 130.

[0043] A pair of terminals 142a and 142b protrude from the side surface 130a towards the negative side in the y-axis direction and are further bent towards the negative side in the x-axis direction. Multiple terminals 152a protrude from the side surface 130b toward the positive side in the y-axis direction and are further bent towards the negative side in the z-axis direction. A pair of terminals 142a and 142b may protrude from the side surface 130a towards the negative side in the y-axis direction and be further bent towards the positive side in the z-axis direction. Multiple terminals 152a may protrude from the side surface 130b toward the positive side in the y-axis direction and be further bent towards the positive side in the z-axis direction. A pair of terminals 142a and 142b, and multiple terminals 152a, do not have to be bent. That is, a pair of terminals 142a and 142b do not have to protrude from the side surface 130a towards the negative side in the y-axis direction and be bent towards the positive and negative sides in the z-axis direction. The multiple terminals 152a protrude from the side surface 130b toward the positive side in the y-axis direction and do not necessarily need to be bent toward the positive and negative sides in the Z-axis direction.

[0044] The lead frame 140 has, in plan view, a slit portion 1411 extending in the y-axis direction and a slit portion 1412 extending in the x-axis direction. The two slit portions 1411 and 1412 are provided on the conductor portion 141 and sealed within the sealing portion 130. The magnetoelectric conversion element 20a is positioned in the slit portion 1411 in plan view and is partially surrounded by the lead frame 140. The magnetoelectric conversion element 20b is positioned in the slit portion 1412 in plan view and is also partially surrounded by the lead frame 140.

[0045] By arranging the magnetoelectric conversion element 20a within the slit portion 1411, the three sides of the magnetoelectric conversion element 20a may be surrounded by the lead frame 140. This prevents the measured current from branching, allowing for a higher current density in the portion of the lead frame 140 closest to the magnetoelectric conversion element 20a, and consequently, enabling higher sensitivity. By arranging the magnetoelectric conversion element 20b within the slit portion 1412, the three sides of the magnetoelectric conversion element 20b may be surrounded by the lead frame 140.

[0046] The magnetoelectric conversion elements 20a and 20b may be fixed to the circuit surface of the signal processing IC 100 by die bonding and 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 multiple wires 22a and 22b. The multiple wires 22a and 22b may be electrically connected to the magnetoelectric conversion elements 20a and 20b and the signal processing IC 100 within the slit portions 1411 and 1412. That is, the multiple wires 22a and 22b may be electrically connected to the magnetoelectric conversion elements 20a and 20b and the signal processing IC 100 without crossing the lead frame 140. By doing so, the magnetic flux linked to the wires can be reduced, making it less likely for induced electromotive force to be generated and facilitating a fast response.

[0047] The magnetoelectric elements 20a and 20b may be electrically connected to the signal processing IC 100 by flip-chip bonding. The magnetoelectric elements 20a and 20b output the signals processed by the signal processing IC 100 to the signal processing IC 100. The magnetoelectric elements 20a and 20b may be configured separately from the signal processing IC 100. That is, the magnetoelectric elements 20a and 20b may be configured on chips other than the chips that make up the signal processing IC 100. The magnetoelectric elements 20a and 20b may be built into the chip that makes up the signal processing IC 100.

[0048] The sealing portion 130 seals the magnetoelectric conversion elements 20a and 20b, the conductor portion 141 of the lead frame 140, the holding portion 151 of the lead frame 150, the signal processing IC 100, the wires 22 and 108 with a molding resin. The molding resin is, for example, an epoxy-based thermosetting resin with silica added, and may be molded into a semiconductor package using a transfer mold.

[0049] Figure 1C shows a first modified example of the internal configuration of the semiconductor package that functions as the current sensor 10 according to this embodiment. Figure 1C, like Figure 1B, is a cross-sectional view of the current sensor 10 shown in Figure 1A, taken along line AA.

[0050] Figure 1D shows a second modified example of the internal configuration of the semiconductor package that functions as the current sensor 10 according to this embodiment. Figure 1D is a cross-sectional view of the current sensor 10 shown in Figure 1A, along line AA, similar to Figure 1B.

[0051] Figure 1E shows a third modified example of the internal configuration of the semiconductor package that functions as the current sensor 10 according to this embodiment. Figure 1E, like Figure 1B, is a cross-sectional view of the current sensor 10 shown in Figure 1A, taken along line AA.

[0052] The current sensor 10 of the first and second modified examples differs from the current sensor 10 according to this embodiment shown in Figure 1B in that 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 multiple terminals 152a at the position where it intersects with the side surface 130b 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 100a opposite to the surface 100a of the signal processing IC 100 of the pair of terminals 142a and 142b (terminal portion 142) at the position where it intersects with the side surface 130a of the sealing portion 130 are the same.

[0053] In the first modified current sensor 10, a stepped portion 1413 is provided on the conductor portion 141 of the lead frame 140, and the conductor portion 141 has a portion 1414 on the bottom surface 130f side of the sealing portion 130 and a portion 1415 on the top surface 130e side of the sealing portion 130, which are connected via the stepped portion 1413. The portion 1414 is also connected to the terminal portion 142. The stepped portion 1413 may be formed by partially cutting the lead frame 140.

[0054] The current sensor 10 of the second modified example has a thicker sealing portion 130 and a larger recess in the holding portion 151 compared to the current sensor 10 of this embodiment shown in Figure 1B.

[0055] The current sensor 10 of the first modified example and the current sensor 10 of the second modified example, by having the above configuration, can maintain the distance between the lead frame 140 and the lead frame 150 and the signal processing IC 100, while making the height in the thickness direction (z-axis direction) of the sealing portion 130 on the same side 1521 of the sealing portion 130 as the side 100a of the signal processing IC 100 at the position where it intersects with the side 130b of the sealing portion 130 the same height in the thickness direction (Z-axis direction) of the sealing portion 130 on the same side 1421 of the sealing portion 130 as the side opposite to the side 100a of the signal processing IC 100 at the position where it intersects with the side 130a of the sealing portion 130. However, the means for making these heights the same are not limited to this.

[0056] The current sensor 10 of the third modified example differs from the current sensor 10 of the second modified example shown in Figure 1B in that a stepped portion 1416 is provided on the conductor portion 141 of the lead frame 140, and the conductor portion 141 has a portion 1417 on the ceiling surface 130e side of the sealing portion 130 and a portion 1418 on the bottom surface 130f side of the sealing portion 130, which are connected via the stepped portion 1416. The portion 1417 is also connected to the terminal portion 142. The stepped portion 1416 may be formed by partially cutting the lead frame 140.

[0057] In the third modified current sensor 10, the height of the sealing portion 130 in the thickness direction (z-axis direction) of the surface 1521 of the multiple terminals 152a at the position where it intersects with the side surface 130b of the sealing portion 130 is lower than the height of the sealing portion 130 in the thickness direction (z-axis direction) of the surface 1421 of the pair of terminals 142a and 142b at the position where it intersects with the side surface 130a of the sealing portion 130. The height of the sealing portion 130 in the thickness direction (z-axis direction) of the surface 1521 of the multiple terminals 152a at the position where it intersects with the side surface 130b of the sealing portion 130 is the same as the height of the sealing portion 130 in the thickness direction (z-axis direction) of the surface 1418 of the conductor portion 1418 facing the signal processing IC 100.

[0058] The third modified current sensor 10 is more preferable because, by having a height difference between portion 1417 and portion 1418, it is easier to release the electric field inside the semiconductor package and suppress partial discharge.

[0059] Figures 1F and 1G show modified semiconductor packages that function as a fourth modified example of the current sensor 10 according to this embodiment. Figure 1F is a schematic plan view of the current sensor 10 according to the fourth modified example, as seen from the ceiling side (z-axis direction). Figure 1G is a cross-sectional view of the current sensor 10 shown in Figure 1F, along line AA.

[0060] The current sensor 10 of the fourth modified example differs from the current sensor 10 shown in Figures 1A and 1B in that the lead frame 150 does not have a holding portion 151, and the surface 141b of the conductive portion 141 of the lead frame 140 and the surface 100a of the signal processing IC 100 are bonded together via insulating tape 30, so that the signal processing IC 100 is held by the lead frame 140.

[0061] In the current sensor 10 of the fourth modified example, the magnetoelectric conversion elements 20a and 20b may be configured as a monolithic structure integrated with the signal processing IC 100, and the magnetoelectric conversion elements 20a and 20b may be provided on the ceiling surface 130e side of the sealing portion 130.

[0062] Furthermore, the parameter T shown in Figures 1B to 1E and Figure 1G ds , T b , T t It is defined as follows: T ds : The shortest distance from the surface 130a of the sealing portion 130 to the lead frame 150 or signal processing IC 100. T b : The distance between the portion of the surface 100b of the signal processing IC 100 or the surface 151b of the conductor portion 150 that is closest to the surface 130a of the sealing portion 130, and the surface 130f of the sealing portion 130. T t : The distance between the portion of the surface 141a of the conductor portion 141 closest to the surface 130b of the sealing portion 130 and the surface 130e of the sealing portion 130 that faces the surface 141a of the conductor portion 141.

[0063] In other words, in Figures 1B to 1E, T ds T is the shortest distance between the surface 130a of the sealing portion 130 and the holding portion 151, and in Figure 1G, ds This is the shortest distance between the surface 130a of the sealing portion 130 and the signal processing IC 100. In Figures 1B to 1E, T b T is the distance between the surface 130f of the sealing portion 130 and the surface 151b of the holding portion 151, and in Figure 1G, bis the distance between the surface 130f of the sealing portion 130 and the surface 100b of the signal processing IC 100. Also, even in the case of a current sensor having a holding portion 151, if the signal processing IC 100 has a structure in which it protrudes more than the holding portion 151 towards the surface 130a of the sealing portion 130, T b This is the distance between the surface 130f of the sealing portion 130 and the surface 100b of the signal processing IC 100.

[0064] In the current sensor 10 configured in this way, it is desirable to more reliably ensure insulation performance when a large current flows through the conductor portion 141 or when a high voltage is applied. Furthermore, in order to enable even larger currents to flow through the conductor portion 141, it is also necessary to suppress the heat generated in the conductor portion 141 caused by the flow of current through it. Heat generation in the conductor portion 141 can be suppressed by reducing the resistance of the conductor portion 141. Reducing the resistance of the conductor portion 141 can be achieved by further increasing the thickness of the conductor portion 141 and shortening it.

[0065] On the other hand, if the thickness of the conductor portion 141 is further increased, the distance between the conductor portion 141 and the surface of the sealing portion 130 may decrease. In this case, when a high voltage is applied to the conductor portion 141, electric field concentration is more likely to occur on the surface of the sealing portion 130, and surface discharge may be induced on the surface of the sealing portion 130 due to the potential difference between the lead frame 140 on the current conductor side and the surroundings. Therefore, it is not easy to design the current sensor 10 in a way that allows a large current to flow through the conductor portion 141 of the current sensor 10 while ensuring insulation performance.

[0066] Therefore, in this embodiment, a current sensor 10 is provided that enables the flow of a large current while ensuring insulation performance.

[0067] To realize such a current sensor 10, this embodiment refers to Darkin's equation, which is empirically known as a predictive formula for the partial discharge initiation voltage. Darkin's equation can be expressed as equation (1). Vp=163(t / ε r ) 0.46 ...(1) Vp is the partial discharge initiation voltage (V / m), ε r is the relative permittivity of the insulating layer, and t is the thickness of the insulating layer (μm).

[0068] The larger the partial discharge initiation voltage Vp, the smaller the electric field E on the surface of the package (sealing portion 130) when a constant voltage V is applied. Therefore, the partial discharge initiation voltage Vp and the electric field E are inversely proportional. In other words, the partial discharge initiation voltage Vp and the electric field E are inversely proportional, and using a constant C', the relationship E = C' × V / Vp holds. Considering E = C' × V / Vp and equation (1), the maximum value Emax of the electric field in a specific region of the package surface when a constant voltage V is applied can be expressed by equation (2). Emax = C × T ds x ×ε y ×V···(2) A specific area on the package surface can be arbitrarily defined to correspond to the location where partial discharge from the surface should be considered.

[0069] Here, C, x, and y are constants, T ds ε is the thickness of the sealing portion 130 on the side, and ε is the relative permittivity of the mold resin constituting the package. The thickness of the sealing portion 130 on the side is the shortest distance from the side 130a where the terminal portion 142 on the current conductor side of the sealing portion 130 is exposed to the holding portion 151 or the signal processing IC 100.

[0070] Here, based on equation (2), Emax [V / m] is proportional to V [V], so the condition under which no surface discharge occurs at a specific voltage V0 [V] is C × T ds x ×ε y It is presumed to be determined by the value of V0[V]. V0[V] can be arbitrarily determined depending on the application, etc.

[0071] In this embodiment, C×T ds x ×ε yA value of less than 400 was considered a condition in which creepage discharge is unlikely to occur on the surface of the sealing portion 130. In other words, it is sufficient if the maximum electric field in a specific region of the package surface, when V=1[V], is less than 400[V / m].

[0072] Using equation (2), in the current sensor shown in Figure 1C, T ds We calculated the electric field E on the package surface using the finite element method by setting various conditions for and ε, and derived the optimal values ​​for C, x, and y. As a result, we found that the values ​​C=523, x=-1, and y=0.08 can be used as approximations.

[0073] Figure 2 shows the maximum electric field Emax and T when a voltage of 1 (V) is applied to the current conductor on the surface (side surface 130a) of the sealing portion 130 in the current sensor shown in Figure 1C, with C = 523, x = -1, and y = 0.08. ds The results based on equation (2), which shows the relationship, and the results based on the finite element method are shown. As shown in Figure 2, when C=523, x=-1, and y=0.08, the results based on equation (2) were consistent with the results based on the finite element method.

[0074] In other words, in this embodiment, the shortest distance from the side surface 130a where the terminal portion 142 on the current conductor side of the sealing portion 130 is exposed to the holding portion 151 or the signal processing IC 100 is T ds If the relative permittivity of the molding resin is ε, then 523 × T ds -1 ×ε 0.08 The shortest distance T from the side surface 130a of the sealing portion 130 to the holding portion 151 or the signal processing IC 100 satisfies <400 (V / m). ds Furthermore, by designing the dielectric constant ε of the mold resin, surface discharge on the surface (surface 130a) of the sealing portion 130 can be prevented.

[0075] Figure 3A shows the current sensor shown in Figure 1C, where when a voltage of 1 (V) is applied to the current conductor, T dsFigure 3B shows the distribution of the magnitude of the electric field E generated by the potential difference around the conductor part 141 when =0.6(mm). Figure 3B shows the current sensor shown in Figure 1C, where a voltage of 1(V) is applied to the current conductor, T ds This shows the distribution of the magnitude of the electric field E generated by the partial discharge occurring between the holding part 151 and the conducting part 141 when T = 1.6 (mm). As shown in Figure 3A, ds When =0.6(mm), the region of strong electric field (E is 400(V / m) or more) extends beyond the surface of the sealing portion 130. On the other hand, as shown in Figure 3B, T ds When the value is 1.6, a region with a strong electric field (E is 400 (V / m) or more) is contained within the sealing portion 130.

[0076] Figure 4 shows the current sensor shown in Figure 1C, with C=523, x=-1, y=0.08, T ds When =0.6, the results based on equation (2), which shows the relationship between the electric field E and the relative permittivity ε when a voltage of 1 (V) is applied to the current conductor on the surface (side surface 130a) of the sealing portion 130, and the results based on the finite element method are shown. ds When = 0.6, even if the relative permittivity ε is reduced, the electric field does not fall below 400 (V / m). In other words, T ds If it is too small, surface discharge on the surface of the sealing portion 130 cannot be suppressed. Therefore, considering the results in Figure 2, in order to prevent surface discharge from occurring on the surface of the sealing portion 130, T ds It is preferable that it is 1.5 mm or more, and more preferably 2.0 mm or more.

[0077] Next, using Darkin's formula as a reference, let V be the partial discharge initiation voltage, and T be the distance between the part of the surface 100b of the signal processing IC 100 or the surface 151b of the conductor part 150 that is closest to the surface 130a of the sealing part 130, and the surface 130f of the sealing part 130. b When the relative permittivity of the molding resin is given by constants ε, C, x, and y, the maximum value Emax of the electric field in a specific region of the package surface when a constant voltage V is applied can be expressed by equation (3). Emax = C × T b x ×ε y×V···(3)

[0078] Here, based on equation (3), Emax [V / m] is proportional to V [V], so the condition under which no surface discharge occurs at a specific voltage V0 [V] is C × T b x ×ε y It is presumed to be determined by the value of V0[V]. V0[V] can be arbitrarily determined depending on the application, etc.

[0079] In this embodiment, C×T b x ×ε y A value of less than 400 was considered a condition in which creepage discharge is unlikely to occur on the surface of the sealing portion 130. In other words, it is sufficient if the maximum electric field in a specific region of the package surface, when V=1[V], is less than 400[V / m].

[0080] Using equation (3), in the current sensor shown in Figure 1D, T b By setting various conditions for and ε, the electric field E on the surface of the package (sealing part 130) was calculated using the finite element method, and the optimal C, x, and y values ​​were derived. As a result, it was found that the values ​​C=470, x=-1, and y=0.08 could be used as approximations.

[0081] Figure 5 shows the maximum value Emax and T of the electric field when a voltage of 1 (V) is applied to the current conductor on the surface (surface 130f) of the sealing portion 130, when C=470, x=-1, and y=0.08, in the current sensor shown in Figure 1D. b The results based on equation (3), which shows the relationship, and the results based on the finite element method are shown. As shown in Figure 5, when C=470, x=-1, and y=0.08, the results based on equation (3) were consistent with the results based on the finite element method.

[0082] In other words, in this embodiment, the distance between the surface 100b of the signal processing IC 100 and the surface 130f of the sealing portion 130 is T b If the relative permittivity of the molding resin is ε, then 470 × T b -1 ×ε 0.08The distance T between the surface 100b of the signal processing IC 100 and the surface 130f of the sealing portion 130 is designed to satisfy <400 (V / m). b By designing the relative permittivity ε of the molding resin, surface discharge on the surface (surface 130f) of the sealing portion 130 can be prevented.

[0083] Considering the results shown in FIG. 5, when T b is 1.35 mm or more, it can be seen that the electric field E on the surface of the sealing portion 130 does not become a strong electric field (400 (V / m) or more). Therefore, in order for the electric field E on the surface (surface 130f) of the sealing portion 130 to satisfy less than 400 (V / m), it can be inferred from FIG. 5 that T b being 1.35 mm or more is sufficient.

[0084] FIG. 6 shows the relationship between the electric field E and the relative permittivity ε when a voltage of 1 (V) is applied to the current conductor on the surface (surface 130f) of the sealing portion 130 in the current sensor shown in FIG. 1D, where C = 470, x = -1, y = 0.08, and T b = 1.37 mm, based on the result of Equation (3) and the result based on the finite element method.

[0085] FIG. 7A shows the distribution of the magnitude of the electric field generated by the potential difference generated around the conductor portion 141 when a voltage of 1 (V) is applied to the current conductor in the current sensor shown in FIG. 1D, where C = 470, x = -1, y = 0.08, and T b = 1.37 mm and ε = 12. FIG. 7B shows the distribution of the magnitude of the electric field generated by the potential difference generated between the holding portion 151 and the conductor portion 141 when a voltage of 1 (V) is applied to the current conductor in the current sensor shown in FIG. 1D, where C = 470, x = -1, y = 0.08, and T b = 1.37 mm and ε = 2. As shown in FIG. 7A, when ε = 12, the region of the strong electric field (E is 400 (V / m) or more) extends beyond the surface of the sealing portion 130. On the other hand, as shown in FIG. 7B, when ε = 2, the region of the strong electric field (E is 400 (V / m) or more) is contained within the sealing portion 130.

[0086] Furthermore, referring to the formula of Darkin, let the partial discharge start voltage be V, and the distance between the surface 130e of the sealing portion 130 facing the surface 141a of the conductor portion 141 be T t , when the relative permittivity of the mold resin is ε, and C, x, and y are constants, the maximum value Emax of the electric field in a specific region on the surface of the package when a constant voltage V is applied can be expressed by Equation (4). Emax = C × T t x × ε y × V ··· (4)

[0087] Here, based on Equation (3), since Emax [V / m] is proportional to V [V], the condition for no creeping discharge to occur at a specific voltage V0 [V] is that the value of C × T t x × ε y is estimated to be determined. V0 [V] may be arbitrarily determined according to the application or the like.

[0088] In this embodiment, it is regarded that the condition for a high possibility of no creeping discharge occurring on the surface of the sealing portion 130 is that the value of C × T t x × ε y is less than 400. In other words, it is sufficient that the maximum value of the electric field in a specific region on the surface of the package when V = 1 [V] is less than 400 [V / m].

[0089] Using Equation (4), in the current sensor shown in FIG. 1D, various conditions of T t and ε were set, the electric field E on the surface of the package was calculated using the finite element method, and the optimal C, x, and y were derived. As a result, it was found that C = 280, x = -0.2, and y = 0.12 are optimal.

[0090] FIG. 8 shows the maximum value Emax of the electric field and T when a voltage of 1 (V) is applied to the current conductor on the surface (surface 130e) of the sealing portion 130 in the current sensor shown in FIG. 1D when C = 280, x = -0.2, and y = 0.12 tThe results based on equation (4), which shows the relationship, and the results based on the finite element method are shown. As shown in Figure 8, when C=280, x=-0.2, and y=0.12, the results based on equation (4) were consistent with the results based on the finite element method.

[0091] In other words, in this embodiment, the distance between the surface 141a of the conductor portion 141 and the surface 130e of the sealing portion 130 facing it is T t If the relative permittivity of the molding resin is ε, then 280 × T t -0.2 ×ε 0.12 The distance T between the surface 141a of the conductor portion 141 and the surface 130e of the sealing portion 130 facing it satisfies <400 (V / m). t Furthermore, by designing the dielectric constant ε of the mold resin, surface discharge on the surface (surface 130e) of the sealing portion 130 can be prevented.

[0092] As shown in Figure 8, approximately T t If the thickness is 0.5 mm or more, more preferably 0.6 mm or more, the electric field E on the surface (surface 130e) of the sealing portion 130 can be reduced to less than 400 (V / m).

[0093] Figure 9 shows the current sensor shown in Figure 1D, with C=280, x=-0.2, y=0.12, T t When the thickness is set to 0.63 mm, the results based on equation (4), which shows the relationship between the electric field E and the relative permittivity ε when a voltage of 1 (V) is applied to the current conductor on the surface (surface 130e) of the sealing portion 130, and the results based on the finite element method are shown. t If the thickness is 0.63 mm, and the relative permittivity ε is 8 or less, more preferably 6 or less, then the electric field E on the surface (surface 130e) of the sealing portion 130 can be kept below 400 (V / m), and surface discharge on the surface of the sealing portion 130 can be prevented.

[0094] Considering the above, in order to prevent surface discharge on each of the surfaces of the sealing portion 130, namely side surface 130a, surface 130e, and surface 130f, the current sensor 10 sets the shortest distance from the side surface 130a where the terminal portion 142 on the current conductor side of the sealing portion 130 is exposed to the holding portion 151 or the signal processing IC 100 to T ds The distance between the surface 100b of the signal processing IC 100 or the surface 151b of the conductor portion 150 that is closest to the surface 130a of the sealing portion 130 and the surface 130f of the sealing portion 130 is T b The distance between the surface 141a of the conductor portion 141 and the surface 130e of the sealing portion 130 facing it is T t If the relative permittivity of the molding resin is ε, 523×T ds -1 ×ε 0.08 <400 (V / m) 470×T b -1 ×ε 0.08 <400 (V / m) 280×T t -0.2 ×ε 0.12 <400 (V / m) It is preferable that the design satisfies each of these conditions.

[0095] Figure 10 shows the conditions table for the sample created as an example. For equations 2, 3, and 4 below, "○" indicates that the formula is satisfied, and "×" indicates that it is not satisfied. Formula (2) 523×Tds-1×ε0.08<400(V / m) Formula (3) 470×Tb-1×ε0.08<400(V / m) Equation (4) 280× Tt-0.2×ε0.12<400(V / m)

[0096] Figure 11 shows the surface discharge generation voltage for each of equations (2), (3), and (4) for each sample. As shown in Figure 11, compared to the case where equations (2), (3), and (4) are not all satisfied, as in Sample 5, a surface discharge suppression effect was observed when one or two of equations (2), (3), and (4) were satisfied, as in Samples 2, 3, and 4. Furthermore, in the case where all of equations (2), (3), and (4) were satisfied, as in Sample 1, a significant surface discharge prevention effect was obtained. Note that which of equations (2), (3), and (4) is most effective depends on the internal structure of the package.

[0097] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications or improvements can be made to the above embodiments. It will be clear from the claims that such modified or improved forms may also be included in the technical scope of the present invention.

[0098] It should be noted that the execution order of operations, procedures, steps, and stages in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not explicitly stated as "before," "prior to," etc., and that these can be implemented in any order unless the output of a previous process is used in a later process. Even if the operation flow in the claims, specifications, and drawings is described using phrases such as "first," "next," etc. for convenience, it does not mean that it is essential to perform the operations in that order. [Explanation of symbols]

[0099] 10 Current Sensor 20a, 20b Magnetoelectric conversion element 22a, 22b, 108 wire 30 Insulating Tape 100 Signal Processing ICs 130 Sealing part 140 Lead Frames 141 Conductor section 142 Terminal section 150 Lead Frames 151 Holding part 152 Terminal section 155 Step section 1411, 1412 Slit section

Claims

1. At least one magnetoelectric conversion unit, A first lead frame includes a first terminal portion and a conductor portion connected to the first terminal portion, through which a measurement current measured by the at least one magnetoelectric conversion unit flows via 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, with 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 second terminal section that outputs a signal from the signal processing IC, The sealing portion that seals the at least one magnetoelectric conversion unit, the conductor unit, the signal processing IC, and a part of the second lead frame with molded resin Equipped with, The shortest distance from the first side surface of the sealing portion where the first terminal portion is exposed to the second lead frame or the signal processing IC is T. ｄｓ When the relative permittivity of the mold resin is ε, 523×T ｄｓ －１ ×ε ０．０８ <400 A current sensor that satisfies the following conditions.

2. T ｄｓ The current sensor according to claim 1, wherein the diameter is 1.6 mm or more.

3. In the signal processing IC, the surface of the conductor portion on the second surface side is the first surface of the signal processing IC, and the surface of the signal processing IC opposite to the first surface is the second surface. The second lead frame has a holding portion on the second side of the signal processing IC for holding the signal processing IC. The current sensor according to claim 1.

4. The shortest distance T ｄｓ This is the distance between the first side surface of the sealing portion and the holding portion. The current sensor according to claim 3.

5. At least one magnetoelectric conversion unit, A first lead frame includes a first terminal portion and a conductor portion connected to the first terminal portion, through which a measurement current measured by the at least one magnetoelectric conversion unit flows via 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, with 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 second terminal section that outputs a signal from the signal processing IC, The sealing portion that seals the at least one magnetoelectric conversion unit, the conductor unit, the signal processing IC, and a part of the second lead frame with molded resin Equipped with, In the signal processing IC, the surface of the conductor portion on the second surface side is the first surface of the signal processing IC, and the surface of the signal processing IC opposite to the first surface is the second surface. In the sealing portion, the surface facing the first surface of the conductor portion is the first surface of the sealing portion, the surface facing the second surface of the conductor portion is the second surface of the sealing portion, and the surface on which the first terminal portion of the conductor portion is exposed is the first side surface. The distance between the second surface of the signal processing IC or the second surface of the conductor portion closest to the first side surface of the sealing portion and the second surface of the sealing portion is T. ｂ When the relative permittivity of the mold resin is ε, 470×T ｂ －１ ×ε ０．０８ <400 A current sensor that satisfies the following conditions.

6. T ｂ The current sensor according to claim 5, wherein the diameter is 1.35 mm or more.

7. In the signal processing IC, the surface of the conductor portion on the second surface side is the first surface of the signal processing IC, and the surface of the signal processing IC opposite to the first surface is the second surface. The second lead frame has a holding portion on the second side of the signal processing IC for holding the signal processing IC. The current sensor according to claim 5.

8. The current sensor according to claim 7, wherein the height of the portion of the conductor that does not overlap with the signal processing IC in the thickness direction from the second surface of the sealing portion is different from the height of the holding portion from the second surface of the sealing portion.

9. At least one magnetoelectric conversion unit, A first lead frame includes a first terminal portion and a conductor portion connected to the first terminal portion, through which a measurement current measured by the at least one magnetoelectric conversion unit flows via 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, with 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 second terminal section that outputs a signal from the signal processing IC, The sealing portion that seals the at least one magnetoelectric conversion unit, the conductor unit, the signal processing IC, and a part of the second lead frame with molded resin Equipped with, In the sealing portion, the surface facing the first surface of the conductor portion is defined as the first surface of the sealing portion, and the surface on which another part of the second lead frame is exposed is defined as the second surface. The distance between the portion of the first surface of the conductor portion closest to the second side surface of the sealing portion and the first surface of the sealing portion facing the first surface of the conductor portion is T. ｔ When the relative permittivity of the mold resin is ε, 280×T ｔ －０．２ ×ε ０．１２ <400 A current sensor that satisfies the following conditions.

10. The shortest distance from the first side surface of the sealing portion where the first terminal portion is exposed to the second lead frame or the signal processing IC is T. ｄｓ In that case, 523×T ｄｓ －１ ×ε ０．０８ <400 The current sensor according to claim 9, which further satisfies the condition.

11. In the signal processing IC, the surface of the conductor portion on the second surface side is the first surface of the signal processing IC, and the surface of the signal processing IC opposite to the first surface is the second surface. In the sealing portion, the surface facing the first surface of the conductor portion is defined as the first surface of the sealing portion, the surface facing the second surface of the conductor portion is defined as the second surface of the sealing portion, and the surface on which the first terminal portion of the conductor portion is exposed is defined as the first side surface. The distance between the second surface of the signal processing IC or the second surface of the conductor portion that is closest to the first side surface of the sealing portion and the second surface of the sealing portion is defined as T. ｂ When that happens, 470×T ｂ －１ ×ε ０．０８ <400 The current sensor according to claim 9, which further satisfies the condition.

12. In the signal processing IC, the surface of the conductor portion on the second surface side is the first surface of the signal processing IC, and the surface of the signal processing IC opposite to the first surface is the second surface. In the sealing portion, the surface facing the first surface of the conductor portion is the first surface of the sealing portion, the surface facing the second surface of the conductor portion is the second surface of the sealing portion, and the surface on which the first terminal portion of the conductor portion is exposed is the first side surface. The shortest distance from the first side surface of the sealing portion to the second lead frame or the signal processing IC is T. ｄｓ The distance between the portion of the second surface of the signal processing IC closest to the first surface of the sealing portion and the second surface of the sealing portion is T. ｂ In that case, 523 x T ｄｓ －１ ×ε ０．０８ <400, and 470 x T ｂ －１ ×ε ０．０８ <400 The current sensor according to claim 9, which further satisfies the condition.

13. In the signal processing IC, the surface of the conductor portion on the second surface side is the first surface of the signal processing IC, and the surface of the signal processing IC opposite to the first surface is the second surface. The second lead frame has a holding portion on the second side of the signal processing IC for holding the signal processing IC. The current sensor according to claim 9.

14. In the sealing portion, the surface facing the first surface of the conductor portion is the first surface of the sealing portion, and the surface facing the second surface of the conductor portion is the second surface of the sealing portion. The conductor portion has a stepped portion, a first portion on the first surface side of the sealing portion connected via the stepped portion, and a second portion on the second surface side of the sealing portion. The first portion is connected to the first terminal portion. A current sensor according to any one of claims 1 to 13.

15. The first surface of the signal processing IC is the circuit surface, The current sensor according to any one of claims 1 to 13, wherein the at least one magnetoelectric conversion element is separate from the signal processing IC.

16. The current sensor according to any one of claims 1 to 13, wherein the signal processing IC incorporates the circuit plane and the at least one magnetoelectric conversion element.

17. The current sensor according to any one of claims 1 to 13, wherein the at least one magnetoelectric conversion element is a Hall element.

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