Current sensor

Abstract

The invention provides a current sensor. This current sensor is provided with: 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 portion, the conductor portion, the signal processing IC, and a portion of the second lead frame with a molding resin. When Tds is the shorter distance from a first side surface exposed from the first terminal portion of the sealing portion to the second lead frame or the signal processing IC, and epsilon is the relative dielectric constant of the molded resin, 523 * Tds-1 * epsilon 0.08 < 400 is satisfied, where Tds is the shorter distance from the first side surface exposed from the first terminal portion of the sealing portion to the second lead frame or the signal processing IC, and epsilon is the relative dielectric constant of the molded resin.

Description

Technical Field

[0001] This invention relates to current sensors. Background Technology

[0002] Patent Document 1 discloses a semiconductor device in which the suspension leads are not exposed on the resin-sealed wall surface at the corner where no suspension leads are provided, in order to ensure minimum surface distance.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2016-152298 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] It is desirable to more reliably ensure the insulation performance of current sensors that measure current values ​​by utilizing magnetoelectric conversion elements to detect changes in the magnetic field generated in a conductor due to current flow.

[0008] Methods for solving problems

[0009] One aspect of the present invention provides a current sensor that includes at least one magnetoelectric conversion unit. The current sensor may include a first lead frame comprising a first terminal portion and a conductor portion connected to the first terminal portion, through which a measuring current measured by the at least one magnetoelectric conversion unit flows. The current sensor may include a signal processing IC disposed on a second side of the conductor portion opposite to a first surface, having a circuit surface on which the at least one magnetoelectric conversion unit is disposed, and processing signals 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 signals 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 portion of the second lead frame using molding resin. The shortest distance between the first side exposed from the first terminal portion of the sealing portion and the second lead frame or the signal processing IC is defined as T. ds When the relative permittivity of the molding resin is set to ε, 523×T can be satisfied. ds -1 ×ε 0.08 <400.

[0010] In the current sensor, T ds It can be 1.6mm or larger.

[0011] Alternatively, in the signal processing IC, the second side of the conductor portion can be designated as the first side of the signal processing IC, and the side opposite to the first side of the signal processing IC can be designated as the second side. The second lead frame has a holding portion for holding the signal processing IC on the second side of the signal processing IC.

[0012] The shortest distance T ds It can be the distance between the first side of the sealing portion and the retaining portion.

[0013] One aspect of the present invention provides a current sensor that includes at least one magnetoelectric conversion unit. The current sensor may include a first lead frame comprising a first terminal portion and a conductor portion connected to the first terminal portion, wherein a measuring 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 side of the conductor portion opposite to the first surface, having a circuit surface on which the at least one magnetoelectric conversion unit is disposed, and processing signals 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 signals 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 portion of the second lead frame using molding resin. In the signal processing IC, the second-side surface of the conductor portion can be designated as the first surface of the signal processing IC, and the surface opposite to the first surface of the signal processing IC can be designated as the second surface. Similarly, in the sealing portion, the surface opposite to the first surface of the conductor portion can be designated as the first surface of the sealing portion, and the surface opposite to the second surface of the conductor portion can be designated as the second surface of the sealing portion. The exposed surface of the first terminal portion of the conductor portion can be designated as the first side surface. The distance between the portion of 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 can be defined as T. b When the relative permittivity of the molding resin is set to ε, it satisfies 470×T. b -1 ×ε 0.08 <400.

[0014] In the current sensor, T b It can be 1.35mm or larger.

[0015] Alternatively, in the signal processing IC, the second side of the conductor portion can be designated as the first side of the signal processing IC, and the side opposite to the first side of the signal processing IC can be designated as the second side. The second lead frame has a holding portion for holding the signal processing IC on the second side of the signal processing IC.

[0016] 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 retaining portion from the second surface of the sealing portion.

[0017] One aspect of the present invention provides a current sensor that includes at least one magnetoelectric conversion unit. The current sensor may include a first lead frame comprising a first terminal portion and a conductor portion connected to the first terminal portion, wherein a measuring 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 side of the conductor portion opposite to the first surface, having a circuit surface on which the at least one magnetoelectric conversion unit is disposed, and processing signals 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 signals 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 portion of the second lead frame using molding resin. Alternatively, in the sealing portion, the surface opposite to the first surface of the conductor portion can be designated as the first surface of the sealing portion, and the exposed surface of the other part of the second lead frame can be designated 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 opposite to the first surface of the conductor portion can be defined as T. t When the relative permittivity of the molding resin is set to ε, it satisfies 280×T. t -0.2 ×ε 0.12 <400.

[0018] In the current sensor, the shortest distance from the first side exposed from the first terminal portion of the seal to the second lead frame or the signal processing IC can be set as T. ds Under the condition that 523×T is still satisfied ds -1 ×ε 0.08 <400.

[0019] In the signal processing IC, the second side of the conductor portion can be designated as the first surface of the signal processing IC, and the side opposite to the first surface of the signal processing IC can be designated as the second surface. In the sealing portion, the surface opposite to the first surface of the conductor portion can be designated as the first surface of the sealing portion, and the surface opposite to the second surface of the conductor portion can be designated as the second surface of the sealing portion. The exposed surface of the first terminal portion of the conductor portion can be designated 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 can be designated as T. b At that time, it also satisfies 470×T b -1 ×ε 0.08 <400.

[0020] In the signal processing IC, the second side of the conductor portion can be designated as the first side of the signal processing IC, and the side opposite to the first side of the signal processing IC can be designated as the second side. In the sealing portion, the side opposite to the first side of the conductor portion can be designated as the first side of the sealing portion, and the side opposite to the second side of the conductor portion can be designated as the second side of the sealing portion. The exposed side of the first terminal portion of the conductor portion can be designated as the first side side. The shortest distance from the first side side of the sealing portion to the second lead frame or the signal processing IC can be designated as T. ds Let T be the distance between the portion of the first side closest to the seal on the second surface of the signal processing IC and the second surface of the seal. b Under the condition that 523×T is still satisfied ds -1 ×ε 0.08 <400 and 470×T b -1 ×ε 0.08 <400.

[0021] Alternatively, in the signal processing IC, the second side of the conductor portion can be designated as the first side of the signal processing IC, and the side opposite to the first side of the signal processing IC can be designated as the second side. The second lead frame has a holding portion for holding the signal processing IC on the second side of the signal processing IC.

[0022] Alternatively, in the sealing portion, the surface opposite to the first surface of the conductor portion can be designated as the first surface of the sealing portion, and the surface opposite to the second surface of the conductor portion can be designated as the second surface of the sealing portion. The conductor portion has a stepped portion and a first portion located on the first surface side of the sealing portion and a second portion located on the second surface side of the sealing portion connected via the stepped portion. The first portion is connected to the first terminal portion.

[0023] In the current sensor, the first surface of the signal processing IC may be the circuit surface, and the at least one magnetoelectric conversion unit may be independent of the signal processing IC.

[0024] In the current sensor, the signal processing IC may have the circuit surface and the at least one magnetoelectric conversion unit built in.

[0025] In the current sensor, the at least one magnetoelectric conversion unit may be a Hall element.

[0026] Furthermore, the above summary of the invention does not list all the features of the invention. Additionally, sub-combinations of these feature groups can also constitute inventions. Attached Figure Description

[0027] Figure 1A This is a schematic top view of the current sensor of this embodiment, viewed from the top surface (z-axis direction).

[0028] Figure 1B yes Figure 1A The image shows a cross-sectional view of the current sensor along line AA.

[0029] Figure 1C This is a sectional view along line AA of a first modified example of the current sensor of this embodiment.

[0030] Figure 1D This is a sectional view along line AA of a second variation of the current sensor of this embodiment.

[0031] Figure 1E This is a cross-sectional view along line AA of the third variation of the current sensor of this embodiment.

[0032] Figure 1F This is a schematic top view of the fourth variation of the current sensor of this embodiment, viewed from the top surface (z-axis direction).

[0033] Figure 1G This is a cross-sectional view (AA) of the fourth variation of the current sensor of this embodiment.

[0034] Figure 2 This shows the electric field E based on the surface representing the sealing part and the distance T. dsThe results of equation (2) and the results based on the finite element method are shown in the figure.

[0035] Figure 3A It shows T ds A diagram showing an example of the distribution of the electric field E generated by partial discharge between the holding part and the conductor part when the value is 0.6.

[0036] Figure 3B It shows T ds A diagram showing an example of the distribution of the electric field E generated by partial discharge between the holding part 151 and the conductor part 141 when the diameter is 1.6 (mm).

[0037] Figure 4 This is shown when C = 523, x = -1, y = 0.08, and T... ds The results of equation (2) based on the relationship between the electric field E and the relative permittivity ε of the sealing surface in the case of =0.6 and the results based on the finite element method are shown in the figure.

[0038] Figure 5 This is shown based on the electric field E representing the surface of the sealing part and the distance T, with C = 470, x = -1, and y = 0.08. b The results of equation (3) and the results based on the finite element method are shown in the figure.

[0039] Figure 6 This is shown when C = 470, x = -1, y = 0.08, and T... b The results of Equation (3) based on the relationship between the electric field E and the relative permittivity ε of the sealing surface in the case of 1.37 mm are shown in the figure and the results based on the finite element method.

[0040] Figure 7A This is shown when C = 470, x = -1, y = 0.08, and T... b A diagram showing the distribution of the electric field between the holding part and the conductor part when ε = 12 and the diameter is 1.37 mm.

[0041] Figure 7B This is shown when C = 470, x = -1, y = 0.08, and T... b A diagram showing the distribution of the electric field between the holding part and the conductor part when ε = 2 and the diameter is 1.37 mm.

[0042] Figure 8 This is shown based on the electric field E representing the surface of the sealing part and the distance T, with C = 280, x = -0.2, and y = 0.12. t The results of equation (4) and the results based on the finite element method are shown in the figure.

[0043] Figure 9 This is shown when C = 280, x = -0.2, y = 0.12, and T... t The results of equation (4) based on the relationship between the electric field E and the relative permittivity ε of the sealing surface in the case of 0.63 mm are shown in the figure and the results based on the finite element method.

[0044] Figure 10 This is a diagram showing the condition table of the sample prepared as an example.

[0045] Figure 11 This is a diagram showing the voltage generated by surface discharge for each sample according to equations (2), (3) and (4).

[0046] Label Explanation

[0047] 10 Current Sensors

[0048] 20a, 20b magnetoelectric conversion elements

[0049] 22a, 22b, 108 wires

[0050] 30 insulation tape

[0051] 100 signal processing IC

[0052] 130 Sealing section

[0053] 140 lead frame

[0054] 141 Conductor section

[0055] 142 Terminal Section

[0056] 150 lead frame

[0057] 151 Maintenance Department

[0058] 152 Terminal Section

[0059] 155 Steps

[0060] 1411, 1412 Slit sections Detailed Implementation

[0061] The present invention will now be described through embodiments thereof, but these embodiments do not limit the invention as defined in the claims. Furthermore, not all combinations of the features described in the embodiments are necessary for the solution of the invention.

[0062] Figure 1A and Figure 1B This shows the internal structure of the semiconductor package that functions as the current sensor 10 in this embodiment. Figure 1AThis is a schematic top view of the current sensor 10 of this embodiment, viewed from the top surface (z-axis direction). Figure 1B yes Figure 1A The current sensor 10 is shown as a sectional view along line AA.

[0063] Regarding coordinates, Figure 1A In this diagram, the direction parallel to the paper and moving upwards is defined as the x-axis, the direction parallel to the paper and moving from right to left is defined as the y-axis, and the direction perpendicular to the paper and moving from the inside towards the front is defined as the z-axis. Any one of the x, y, or z axes is orthogonal to the other axes.

[0064] 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 part 130.

[0065] 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 a sealing portion 130 and, when viewed from above, partially surrounds the magnetoelectric conversion elements 20a and 20b together with a portion of the terminal portion 142. A measuring current flows through the terminal portion 142 and the conductor portion 141. The pair of terminals 142a and 142b are physically integrated with the conductor portion 141 and exposed 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 lead frame in the form of multiple interconnected conductor portions 141 and terminal portions 142; it can also be manufactured using a lead frame in the form of a monolithic metal component.

[0066] 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 a sealing portion 130 to hold the signal processing IC 100. The signal processing IC 100 can be fixed to the surface 151a of the holding portion 151 via an adhesive layer. The adhesive layer can be a chip mounting film.

[0067] 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, in order to ensure the insulation between the lead frame 140 and the lead frame 150 or the signal processing IC 100, a step may be provided in the thickness direction on at least one of the lead frame 140 and the lead frame 150. 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) away from the conductor portion 141 (bottom surface side of the sealing portion 130). The stepped portion 155 may be formed by performing a semi-through process on the lead frame 150. Alternatively, the stepped portion 155 may not be provided.

[0068] Multiple terminals 152a are physically integrated with the retaining portion 151 and 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 with copper as the main component.

[0069] Here, the x-axis is the direction along the surfaces of lead frames 140 and 150, and is the direction in which the multiple terminals 152a are arranged. The y-axis is the direction along the surfaces of lead frames 140 and 150, and is the direction that intersects the x-axis. When viewed from above, the y-axis is also the direction in which the multiple terminals 152a and a pair of terminals 142a, 142b extend. The z-axis is the direction that intersects the surfaces of lead frames 140 and 150, and is also the direction that intersects the circuit surface (surface 100a) of the signal processing IC 100, and is also the thickness direction of the sealing portion 130.

[0070] A pair of terminals 142a and 142b and a plurality of terminals 152a are arranged opposite to the signal processing IC 100 in a direction (y-axis direction) intersecting the thickness direction (z-axis direction) of the signal processing IC 100. The pair of terminals 142a and 142b protrude from the side 130a of the sealing portion 130. The plurality of terminals 152a protrude from the side 130b of the sealing portion 130 opposite to the side 130a.

[0071] A pair of terminals 142a and 142b may have a portion that is away from the side 130a of the sealing portion 130 and bends towards the bottom surface 130f of the sealing portion in the thickness direction. A plurality of terminals 152a may have a portion that is away from the side 130b of the sealing portion and bends towards 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 plurality of terminals 152a in the thickness direction may not be towards the bottom surface 130f of the sealing portion 130, but rather towards the top surface 130e of the sealing portion.

[0072] Magnetoelectric conversion elements 20a and 20b are electrically connected to the signal processing IC 100 via multiple wires 22a and 22b. The magnetoelectric conversion elements 20a and 20b are separately configured from the signal processing IC 100 and output the signal processed by the signal processing IC 100 to the signal processing IC 100. The signal processing IC 100 is electrically connected to multiple terminals 152a via wire 108. Wires 22a and 22b and wire 108 can be formed of a conductive material primarily composed of Au, Ag, Cu, or Al.

[0073] The magnetoelectric conversion elements 20a and 20b can protrude from the surface 100a of the signal processing IC 100 in such a way that the magnetosensitive surface of the magnetoelectric conversion elements 20a and 20b overlaps with the conductor portion 141 when viewed from the side. This improves the sensitivity of the magnetoelectric conversion elements 20a and 20b.

[0074] Magnetoelectric conversion elements 20a and 20b detect magnetic fields in a specific direction that change according to the measuring current flowing through conductor 141. Signal processing IC 100 amplifies the signal corresponding to the magnitude of the magnetic field and outputs the amplified signal via terminal 152a. Magnetoelectric conversion elements 20a and 20b are made of compound semiconductors formed on a GaAs substrate and can be chips cut into a square or rectangle when viewed from above in the z-axis direction.

[0075] Magnetoelectric conversion elements 20a and 20b may have a substrate made of silicon or a compound semiconductor and a magnetoelectric conversion section disposed on the substrate. The thickness of the substrate is adjusted by grinding the negative side surface in the z-axis direction. Since the magnetic field in the z-axis direction is detected, a horizontal Hall element, for example, is suitable as the magnetoelectric conversion elements 20a and 20b. Furthermore, if the magnetoelectric conversion elements 20a and 20b are positioned to detect the magnetic field in either axial direction of the xy-plane, then, for example, if positioned to detect the magnetic field in the x-axis direction, a magnetoresistive element or a fluxgate magnetoresistive 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).

[0076] In this embodiment, the magnetoelectric conversion elements 20a and 20b are not built into the signal processing IC 100, but are disposed on the circuit surface (surface 100a). That is, the magnetoelectric conversion elements 20a and 20b of the current sensor 10 are independently constructed from the signal processing IC 100, and are not a monolithic structure. However, the magnetoelectric conversion elements 20a and 20b may also be constructed as a monolithic structure built into the signal processing IC 100. In addition, in this embodiment, an example of the current sensor 10 having two magnetoelectric conversion elements 20a and 20b is described. However, the current sensor 10 only needs to have one or more magnetoelectric conversion elements.

[0077] The signal processing IC 100 is a large-scale integrated circuit (LSI). The signal processing IC 100 is a signal processing circuit composed of a single Si semiconductor wafer formed on a Si substrate. The signal processing circuit processes the output signal corresponding to the magnitude of the magnetic field output from the magnetoelectric conversion elements 20a and 20b. The signal processing circuit corrects the measured current flowing through the conductor portion 141 based on the output signal and outputs an output signal representing the corrected current value via terminal 152a. That is, the signal processing IC 100 and the lead frame 150 are electrically connected via wires, etc. Based on the difference between the output signals of magnetoelectric conversion elements 20a and 20b, the signal processing circuit reduces the noise components contained in the output signals of magnetoelectric conversion elements 20a and 20b, adds and amplifies the noise-reduced output signals of magnetoelectric conversion elements 20a and 20b, calculates the measured current value based on the amplified output signal, and outputs an output signal representing the current value.

[0078] like Figure 1B As shown, a pair of terminals 142a and 142b and a plurality of terminals 152a can 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 portion of the conductor portion 141 that does not overlap with the signal processing IC 100 in the thickness direction (z-axis direction) from the bottom surface (surface 130f) of the sealing portion 130 is different from the height of the holding portion 151 from the surface 130f of the sealing portion 130.

[0079] The height of the surface 1521 of the plurality of terminals 152a at the location intersecting with the side surface 130b of the sealing portion 130, which is the same as the surface 100a of the signal processing IC 100, in the thickness direction (z-axis direction) of the sealing portion 130, can be the same as the height of the surface 1421 of the pair of terminals 142a, 142b at the location intersecting with the side surface 130a of the sealing portion 130, which is the same as the surface opposite to the surface 100a of the signal processing IC 100, in the thickness direction (z-axis direction) of the sealing portion 130. Alternatively, the height of the surface 1521 of the plurality of terminals 152a at the location intersecting with the side surface 130b of the sealing portion 130 in the thickness direction (z-axis direction) of the sealing portion 130 can be located lower than the height of the surface 1421 of the pair of terminals 142a, 142b at the location intersecting with the side surface 130a of the sealing portion 130 in the thickness direction (z-axis direction) of the sealing portion 130.

[0080] exist Figure 1BIn the current sensor, the height of the surface 1521 of a plurality of terminals 152a at the position where they intersect with the side surface 130b of the sealing portion 130 in the thickness direction (z-axis direction) of the sealing portion 130 is lower than the height of the surface 1421 of a pair of terminals 142a, 142b at the position where they intersect with the side surface 130a of the sealing portion 130 in the thickness direction (z-axis direction) of the sealing portion 130.

[0081] A pair of terminals 142a and 142b protrude from side 130a toward the negative side in the y-axis direction, and then bends toward the negative side in the x-axis direction. Multiple terminals 152a protrude from side 130b toward the positive side in the y-axis direction, and then bends toward the negative side in the z-axis direction. Alternatively, the pair of terminals 142a and 142b may protrude from side 130a toward the negative side in the y-axis direction, and then bend toward the positive side in the z-axis direction. Alternatively, multiple terminals 152a may protrude from side 130b toward the positive side in the y-axis direction, and then bend toward the positive side in the z-axis direction. Alternatively, the pair of terminals 142a and 142b and the multiple terminals 152a may not be bent. That is, the pair of terminals 142a and 142b may also protrude from side 130a toward the negative side in the y-axis direction, without bending toward the positive or negative side in the z-axis direction. Multiple terminals 152a can also protrude from the side 130b toward the positive side in the y-axis direction, without bending toward the positive and negative sides in the Z-axis direction.

[0082] The lead frame 140, when viewed from above, has a slit portion 1411 extending along the y-axis and a slit portion 1412 extending along the x-axis. The two slit portions 1411 and 1412 are disposed within the conductor portion 141 and sealed within the sealing portion 130. The magnetoelectric conversion element 20a, when viewed from above, is disposed within the slit portion 1411, and is thus partially surrounded by the lead frame 140. Furthermore, the magnetoelectric conversion element 20b, when viewed from above, is disposed within the slit portion 1412, and is thus partially surrounded by the lead frame 140.

[0083] By placing the magnetoelectric conversion element 20a within the slit portion 1411, the three sides of the magnetoelectric conversion element 20a can be surrounded by the lead frame 140. As a result, the measured current does not branch, and the current density can be increased in the portion of the lead frame 140 near the magnetoelectric conversion element 20a, thereby further improving sensitivity. By placing the magnetoelectric conversion element 20b within the slit portion 1412, the three sides of the magnetoelectric conversion element 20b can be surrounded by the lead frame 140.

[0084] Magnetoelectric conversion elements 20a and 20b can be chip-bonded to the circuit surface of the signal processing IC 100 and electrically connected to the signal processing IC 100 via wire bonding. That is, magnetoelectric conversion elements 20a and 20b can be electrically connected to the signal processing IC 100 via multiple wires 22a and 22b. The multiple wires 22a and 22b can be electrically connected to the magnetoelectric conversion elements 20a and 20b and the signal processing IC 100 within the slits 1411 and 1412. In other words, the multiple wires 22a and 22b can connect the magnetoelectric conversion elements 20a and 20b to the signal processing IC 100 without crossing the lead frame 140. This reduces magnetic flux linkage with the wires, minimizes the generation of induced electromotive force, and facilitates high-speed response.

[0085] Magnetoelectric conversion elements 20a and 20b can also be electrically connected to the signal processing IC 100 via flip-chip bonding. Magnetoelectric conversion elements 20a and 20b output the signal processed by the signal processing IC 100 to the signal processing IC 100. Magnetoelectric conversion elements 20a and 20b can be constructed separately from the signal processing IC 100. That is, magnetoelectric conversion elements 20a and 20b can be constructed from chips different from those constituting the signal processing IC 100. Alternatively, magnetoelectric conversion elements 20a and 20b can be integrated within the chip constituting the signal processing IC 100.

[0086] 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 wire 22, and the wire 108 using molding resin. The molding resin is, for example, a thermosetting epoxy resin containing silica, and can be formed into a semiconductor package through transfer molding.

[0087] Figure 1C This shows a first variation of the internal structure of the semiconductor package in which the current sensor 10 functions as described in this embodiment. Figure 1C and Figure 1B Similarly, Figure 1A The current sensor 10 is shown as a sectional view along line AA.

[0088] Figure 1D This is a second variation of the internal structure of the semiconductor package in which the current sensor 10 functions as described in this embodiment. Figure 1D and Figure 1B Similarly, Figure 1A The current sensor 10 is shown as a sectional view along line AA.

[0089] Figure 1E This is a third variation of the internal structure of the semiconductor package in which the current sensor 10 functions as described in this embodiment. Figure 1E and Figure 1BSimilarly, Figure 1A The current sensor 10 is shown as a sectional view along line AA.

[0090] The current sensor 10 in the first and second modifications and Figure 1B The difference in the current sensor 10 of this embodiment is that the height of the surface 1521 of the plurality of terminals 152a at the position intersecting with the side surface 130b of the sealing portion 130, which is the same as the surface 100a of the signal processing IC 100, in the thickness direction (z-axis direction) of the sealing portion 130 is the same as the height of the surface 1421 of the pair of terminals 142a, 142b (terminal portion 142) at the position intersecting with the side surface 130a of the sealing portion 130, which is the same as the surface opposite to the surface 100a of the signal processing IC 100, in the thickness direction (z-axis direction) of the sealing portion 130.

[0091] In the first modified current sensor 10, a stepped portion 1413 is provided in the conductor portion 141 of the lead frame 140. The conductor portion 141 has a portion 1414 located on the bottom surface 130f side of the sealing portion 130 and a portion 1415 located 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 can be formed by performing a semi-through machining on the lead frame 140.

[0092] The current sensor 10 in the second variation and Figure 1B Compared to the current sensor 10 of this embodiment, the sealing portion 130 is thicker and the recess of the holding portion 151 is larger.

[0093] By having the above-described structure, the current sensor 10 of the first and second modifications can, while maintaining the distance between the lead frame 140 and the lead frame 150 and the signal processing IC 100, make the height of the surface 1521 of the plurality of terminals 152a at the position intersecting the side surface 130b of the sealing portion 130, which is the same as the surface 100a of the signal processing IC 100, in the thickness direction (z-axis direction) of the sealing portion 130, and the height of the surface 1421 of the pair of terminals 142a, 142b (terminal portion 142) at the position intersecting the side surface 130a of the sealing portion 130, which is the same as the opposite side of the surface 100a of the signal processing IC 100, in the thickness direction (z-axis direction) of the sealing portion 130, in the thickness direction (z-axis direction) of the sealing portion 130. However, the means to make these heights the same are not limited to this.

[0094] The current sensor 10 in the third variation and Figure 1BThe difference in the current sensor 10 of the second modified example shown is that a stepped portion 1416 is provided in the conductor portion 141 of the lead frame 140. The conductor portion 141 has a portion 1417 located on the top surface 130e side of the sealing portion 130 and a portion 1418 located on the bottom surface 130f side of the sealing portion 130, connected via the stepped portion 1416. The portion 1417 is also connected to the terminal portion 142. The stepped portion 1416 can be formed by performing a semi-through machining on the lead frame 140.

[0095] In the current sensor 10 of the third variation, the height of the surface 1521 of the plurality of terminals 152a at the position where they intersect with the side surface 130b of the sealing portion 130 in the thickness direction (z-axis direction) of the sealing portion 130 is lower than the height of the surface 1421 of the pair of terminals 142a, 142b at the position where they intersect with the side surface 130a of the sealing portion 130 in the thickness direction (z-axis direction) of the sealing portion 130. The height of the surface 1521 of the plurality of terminals 152a at the position where they intersect with the side surface 130b of the sealing portion 130 in the thickness direction (z-axis direction) of the sealing portion 130 is the same as the height of the surface of the conductor portion 1418 opposite to the signal processing IC 100 in the thickness direction (z-axis direction) of the sealing portion 130.

[0096] The current sensor 10 of the third modification, by having a height difference between portion 1417 and portion 1418, can easily release the electric field inside the semiconductor package and suppress partial discharge, which is more preferable.

[0097] Figure 1F and Figure 1G This invention shows a fourth variation of the semiconductor package that functions as the current sensor 10 of this embodiment. Figure 1F This is a schematic top view of the current sensor 10 of the fourth variation, viewed from the top side (z-axis direction). Figure 1G yes Figure 1F The current sensor 10 is shown as a sectional view along line AA.

[0098] The current sensor 10 in the fourth variation and Figure 1A and Figure 1B The difference in the current sensor 10 shown is that the lead frame 150 does not have a holding part 151, and the surface 141b of the conductor part 141 of the lead frame 140 is bonded to the surface 100a of the signal processing IC 100 via an insulating tape 30, and the signal processing IC 100 is held in the lead frame 140.

[0099] In the current sensor 10 of the fourth variation, the magnetoelectric conversion elements 20a and 20b can be composed of a monolithic structure integrated with the signal processing IC 100, and the magnetoelectric conversion elements 20a and 20b can be disposed on the top surface 130e side of the sealing part 130.

[0100] in addition, Figures 1B to 1E and Figure 1G The recorded parameter T ds T b T t Defined as follows.

[0101] T ds The shortest distance from the surface 130a of the sealing portion 130 to the lead frame 150 or the signal processing IC 100.

[0102] T b The distance between the portion of surface 100b of the signal processing IC 100 or surface 151b of the conductor portion 150 closest to surface 130a of the sealing portion 130 and surface 130f of the sealing portion 130.

[0103] T t The distance between the portion of the conductor portion 141a closest to the sealing portion 130b and the sealing portion 130e opposite to the conductor portion 141a.

[0104] That is, in Figures 1B to 1E In the middle, T ds It is the shortest distance between the surface 130a of the sealing part 130 and the retaining part 151. Figure 1G In the middle, T ds It is the shortest distance between the surface 130a of the sealing part 130 and the signal processing IC 100.

[0105] exist Figures 1B to 1E In the middle, T b It is the distance between the surface 130f of the sealing part 130 and the surface 151b of the retaining part 151. Figure 1G In the middle, 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. Furthermore, even with a current sensor having a holding portion 151, if the signal processing IC 100 is configured to protrude further towards the surface 130a of the sealing portion 130 than the holding portion 151, T... b It is the distance between the surface 130f of the sealing part 130 and the surface 100b of the signal processing IC 100.

[0106] In this current sensor 10 configuration, it is desirable to more reliably ensure insulation performance when a large current flows through the conductor portion 141 or a high voltage is applied. Furthermore, in order to allow a larger current to flow through the conductor portion 141, it is also necessary to suppress the heating of the conductor portion 141 caused by the current flowing through it. This heating can be suppressed by reducing the resistance of the conductor portion 141. The reduction of the resistance of the conductor portion 141 can be achieved by further increasing and decreasing the thickness of the conductor portion 141.

[0107] 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 become shorter. In this case, by applying a high voltage to the conductor portion 141, an electric field concentration is easily generated on the surface of the sealing portion 130. Due to the potential difference between the lead frame 140 on the current conductor side and its surroundings, surface discharge may be induced on the surface of the sealing portion 130. Therefore, it is not easy to design the current sensor 10 to allow a large current to flow through the conductor portion 141 of the current sensor 10 and to ensure insulation performance.

[0108] Therefore, in this embodiment, a current sensor 10 is provided that can carry large currents and ensure insulation performance.

[0109] To realize such a current sensor 10, in this embodiment, the formula for predicting the partial discharge initiation voltage is referenced to Darkin's formula, which is known empirically. Darkin's formula can be expressed by equation (1).

[0110] Vp=163(t / ε r ) 0.46 …(1) Vp is the partial discharge initiation voltage (V), ε r t is the relative permittivity of the insulating layer, and t is the thickness of the insulating layer (μm).

[0111] The larger the partial discharge initiation voltage Vp, the smaller the electric field E on the surface of the package (sealing part 130) when a certain voltage V is applied. Therefore, the partial discharge initiation voltage Vp and the electric field E are inversely related. That is, the partial discharge initiation voltage Vp and the electric field E are inversely proportional. Using the constant C′, the relationship is E=C′×V / Vp. Therefore, if we consider E=C′×V / Vp and equation (1), the maximum value Emax of the electric field in a specific region on the surface of the package when a certain voltage V is applied can be expressed by equation (2).

[0112] Emax=C×T ds x ×ε y ×V…(2)

[0113] A specific area on the surface of the package can be arbitrarily determined based on the location from which partial discharge from the surface is desired.

[0114] Here, C, x, and y are constants, and T ds ε is the thickness of the side sealing portion 130, and ε is the relative permittivity of the molding resin constituting the package. The thickness of the side sealing portion 130 is the shortest distance from the side 130a exposed from the terminal portion 142 on the current conductor side of the sealing portion 130 to the holding portion 151 or the signal processing IC 100.

[0115] Here, based on equation (2), Emax[V / m] is proportional to V[V], therefore it is presumed that the condition for no surface discharge to occur at a specific voltage V0[V] is determined by C×T. ds x ×ε y The value of V0[V] is determined by its purpose.

[0116] In this embodiment, C×T ds x ×ε y A value less than 400 is considered a condition where the possibility of surface discharge not occurring on the surface of the sealing part 130 is high. In other words, it is acceptable as long as 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].

[0117] Using equation (2), in Figure 1C In the current sensor shown, various T values ​​are set. ds Given the condition ε, the electric field E on the surface of the package is calculated using the finite element method, and the optimal C, x, and y are derived. The results show that they can be approximated as C = 523, x = -1, and y = 0.08.

[0118] Figure 2 Shown in Figure 1C In the current sensor shown, with C = 523, x = -1, and y = 0.08, the maximum value Emax of the electric field when a voltage of 1 (V) is applied to the current conductor on the surface (side surface 130a) of the sealing part 130 is compared with T. ds The results of equation (2) and the results based on the finite element method. For example... Figure 2 As shown, with C = 523, x = -1, and y = 0.08, the result based on equation (2) becomes the result suitable for the finite element method.

[0119] That is, in this embodiment, the shortest distance from the side 130a exposed from the current conductor side of the sealing portion 130 to the holding portion 151 or the signal processing IC 100 is set as T. dsIf the relative permittivity of the molding resin is set to ε, and if 523×T is satisfied... ds -1 ×ε 0.08 The design is based on a minimum distance T between the side 130a of the sealing part 130 and the holding part 151 or the signal processing IC 100, with a value <400 (V / m). ds The relative permittivity ε of the molding resin can prevent surface discharge on the surface (surface 130a) of the sealing part 130.

[0120] Figure 3A Shown in Figure 1C In the current sensor shown, when a voltage of 1 (V) is applied to the current conductor, T ds The distribution of the magnitude of the electric field E generated by the potential difference around the conductor portion 141 when the diameter is 0.6 (mm). Figure 3B Indicates in Figure 1C In the current sensor shown, when a voltage of 1 (V) is applied to the current conductor, T ds The distribution of the electric field E generated by partial discharge between the holding part 151 and the conductor part 141 when the diameter is 1.6 (mm). Figure 3A As shown, in T ds When the voltage is 0.6 mm, the region of strong electric field (E = 400 V / m or more) extends beyond the surface of the sealing portion 130. On the other hand, as... Figure 3B As shown, in T ds When the value is 1.6, the region of strong electric field (E is 400 (V / m) or more) converges within the sealing part 130.

[0121] Figure 4 Shown in Figure 1C In the current sensor shown, with C = 523, x = -1, y = 0.08, and T... ds In the case of 0.6, the results are based on equation (2), which expresses 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 130a) of the sealing part 130, and the results based on the finite element method. In T ds With a relative permittivity of 0.6, even if the relative permittivity ε is reduced, the electric field will not be lower than 400 (V / m). That is, if T ds If it is too small, it will be unable to suppress surface discharge on the surface of the sealing part 130. Therefore, if considering Figure 2 As a result, in order to prevent surface discharge from occurring on the surface of the sealing part 130, T ds Preferably, the thickness is 1.5 mm or more, and more preferably 2.0 mm or more.

[0122] Next, referring to Darkin's formula, with the partial discharge initiation voltage set to V, and the distance between the portion of the signal processing IC 100 surface 100b or the conductor portion 150 surface 151b closest to the sealing portion 130a and the sealing portion 130f surface 130f set to T, the partial discharge initiation voltage is set to V. b When the relative permittivity of the molding resin is set to ε and C, x, and y are set to constants, the maximum value of the electric field Emax in a specific region of the surface of the package when a certain voltage V is applied can be expressed by equation (3).

[0123] Emax=C×T b x ×ε y ×V…(3)

[0124] Here, based on equation (3), Emax[V / m] is proportional to V[V], therefore it is presumed that the condition for no surface discharge to occur at a specific voltage V0[V] is determined by C×T. b x ×ε y The value of V0[V] is determined by its purpose.

[0125] In this embodiment, C×T b x ×ε y A value less than 400 is considered a condition where the possibility of surface discharge not occurring on the surface of the sealing part 130 is high. In other words, it is acceptable as long as 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].

[0126] Using equation (3), in Figure 1D In the current sensor shown, various T values ​​are set. b Given the condition ε, the electric field E on the surface of the package (sealing part 130) is calculated using the finite element method, and the optimal C, x, and y are derived. The results show that they can be approximated as C = 470, x = -1, and y = 0.08.

[0127] Figure 5 Shown in Figure 1D In the current sensor shown, with C = 470, x = -1, and y = 0.08, the maximum value Emax of the electric field when a voltage of 1 (V) is applied to the current conductor on the surface (face 130f) of the sealing part 130 is compared with T. b The results of equation (3) and the results based on the finite element method. For example Figure 5 As shown, with C = 470, x = -1, and y = 0.08, the result based on equation (3) becomes the result suitable for the result based on the finite element method.

[0128] That is, 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 set as T. b If the relative permittivity of the molding resin is set to ε, and if 470×T is satisfied... b -1 ×ε 0.08 The distance T between surface 100b of signal processing IC 100 and surface 130f of sealing portion 130 is designed in a manner with a voltage rating of <400 (V / m). b The relative permittivity ε of the molding resin can prevent surface discharge on the surface (surface 130f) of the sealing part 130.

[0129] If considering Figure 5 The results shown indicate that if T b If the electric field E on the surface of the sealing portion 130 is 1.35 mm or more, then the electric field E will not become a strong electric field (400 V / m or more). Therefore, in order to satisfy that the electric field E on the surface (surface 130f) of the sealing portion 130 is less than 400 V / m, according to Figure 5 It is possible to deduce T b A diameter of 1.35mm or larger is acceptable.

[0130] Figure 6 Shown in Figure 1D In the current sensor shown, with C = 470, x = -1, y = 0.08, and T... b In the case of 1.37 mm, the results are based on Equation (3), which expresses the relationship between the electric field E and the relative permittivity ε when a voltage of 1 (V) is applied to the current conductor of the sealing part 130 (face 130f), and the results based on the finite element method.

[0131] Figure 7A Shown in Figure 1D In the current sensor shown, with a voltage of 1 V applied to the current conductor, let C = 470, x = -1, y = 0.08, and T... b The distribution of the magnitude of the electric field generated around the conductor portion 141 due to the potential difference when the diameter is 1.37 mm and the ε is 12. Figure 7B Shown in Figure 1D In the current sensor shown, with a voltage of 1 V applied to the current conductor, let C = 470, x = -1, y = 0.08, and T... b The distribution of the electric field magnitude generated by the potential difference between the holding part 151 and the conductor part 141 when ε = 1.37 mm and ε = 2. For example... Figure 7A As shown, when ε = 12, the region of strong electric field (E = 400 (V / m) or higher) extends beyond the surface of the sealing portion 130. On the other hand, as... Figure 7BAs shown, when ε=2, the region of strong electric field (E is 400 (V / m) or more) converges within the sealing part 130.

[0132] Furthermore, referring to Darkin's formula, with the partial discharge initiation voltage set to V, and the distance between the surface 141a of the conductor portion 141 and the surface 130e of the opposing sealing portion 130 set to T, t When the relative permittivity of the molding resin is set to ε and C, x, and y are set to constants, the maximum value of the electric field Emax in a specific region on the surface of the package when a certain voltage V is applied can be expressed by equation (4).

[0133] Emax=C×T t x ×ε y ×V…(4)

[0134] Here, based on equation (3), Emax[V / m] is proportional to V[V], therefore it is presumed that the condition for no surface discharge to occur at a specific voltage V0[V] is determined by C×T. t x ×ε y The value of V0[V] is determined by its purpose.

[0135] In this embodiment, C×T t x ×ε y A value less than 400 is considered a condition where the possibility of surface discharge not occurring on the surface of the sealing part 130 is high. In other words, it is acceptable as long as 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].

[0136] Using equation (4), in Figure 1D In the current sensor shown, various T values ​​are set. t Given the condition ε, the electric field E on the surface of the package is calculated using the finite element method, and the optimal values ​​of C, x, and y are derived. The results show that C = 280, x = -0.2, and y = 0.12 are optimal.

[0137] Figure 8 Shown in Figure 1D In the current sensor shown, with C = 280, x = -0.2, and y = 0.12, the maximum value Emax of the electric field when a voltage of 1 (V) is applied to the current conductor on the surface (face 130e) of the sealing part 130 is compared with T. t The results of equation (4) and the results based on the finite element method. For example... Figure 8 As shown, with C = 280, x = -0.2, and y = 0.12, the result based on equation (4) becomes a result suitable for the finite element method.

[0138] That is, in this embodiment, the distance between the surface 141a of the conductor portion 141 and the surface 130e of the opposite sealing portion 130 is set as T. t If the relative permittivity of the molding resin is set to ε, and if 280×T is satisfied... t -0.2 ×ε 0.12 The distance T between the surface 141a of the conductor portion 141 and the surface 130e of the opposite sealing portion 130 is designed in a manner of <400 (V / m). t The relative permittivity ε of the molding resin can prevent surface discharge on the surface (surface 130e) of the sealing part 130.

[0139] like Figure 8 As shown, if 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 part 130 can be less than 400 (V / m).

[0140] Figure 9 Indicates in Figure 1D In the current sensor shown, with C = 280, x = -0.2, y = 0.12, and T... t In the case of 0.63 mm, the results are based on equation (4), which expresses 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 part 130, and the results based on the finite element method. t When the relative permittivity ε is 0.63 mm, if the relative permittivity ε is 8 or less, more preferably 6 or less, the electric field E on the surface (surface 130e) of the sealing part 130 can be less than 400 (V / m), and surface discharge of the sealing part 130 can be prevented.

[0141] Considering the above, in order to prevent surface discharge on the side surface 130a, surface 130e, and surface 130f of the sealing part 130, the current sensor 10 sets the shortest distance from the side surface 130a exposed from the terminal part 142 on the current conductor side of the sealing part 130 to the holding part 151 or the signal processing IC 100 to the holding part 151. ds Let T be the distance between the portion of the surface 100b of the signal processing IC 100 or the surface 151b of the conductor portion 150 closest to the surface 130a of the sealing portion 130 and the surface 130f of the sealing portion 130. b The distance between the surface 141a of the conductor portion 141 and the surface 130e of the opposite sealing portion 130 is set as T. t When the relative permittivity of the molding resin is set to ε, it is preferable to design it to satisfy the following conditions.

[0142] 523×T ds -1 ×ε 0.08 <400 (V / m)

[0143] 470×T b -1 ×ε 0.08 <400 (V / m)

[0144] 280×T t -0.2 ×ε 0.12 <400 (V / m)

[0145] Figure 10 This is a condition table for samples prepared as examples. For Equations 2, 3, and 4 below, "〇" indicates that the formula is satisfied, and "×" indicates that it is not satisfied.

[0146] Equation (2) 523×T ds -1 ×ε 0.08 <400 (V / m)

[0147] Equation (3) 470×T b -1 ×ε 0.08 <400 (V / m)

[0148] Equation (4) 280×T t -0.2 ×ε 0.12 <400 (V / m)

[0149] Figure 11 The voltage generated by surface discharge for each sample is represented by equations (2), (3), and (4). Figure 11 As shown, compared to the case where not all of Equations (2), (3), and (4) are satisfied, the case where one or two of Equations (2), (3), and (4) are satisfied, as in Sample 5, confirms a surface discharge suppression effect. Furthermore, when all of Equations (2), (3), and (4) are satisfied, as in Sample 1, a significant surface discharge prevention effect can be obtained. In addition, which of Equations (2), (3), and (4) exhibits the greatest effect depends on the internal structure of the PKG (package).

[0150] The present invention has been described above using embodiments, but the technical scope of the present invention is not limited to the scope described in the above embodiments. Various modifications or improvements can be made to the above embodiments, which will be apparent to those skilled in the art. As can be seen from the claims, such modifications or improvements are also included within the technical scope of the present invention.

[0151] It should be noted that the execution order of actions, processes, steps, and stages in the apparatus, system, program, and method shown in the claims, specification, and drawings can be implemented in any order, as long as it is not specifically stated as "before" or "prior to" and the output of an earlier process is not used in a later process. Even if terms such as "firstly" or "next" are used to describe the flow of actions in the claims, specification, and drawings for convenience, this does not mean that they must be performed in that order.

Claims

1. A current sensor, comprising: At least one magnetoelectric conversion unit; The first lead frame includes a first terminal portion and a conductor portion connected to the first terminal portion, wherein a measuring current measured by the at least one magnetoelectric conversion portion flows through the first terminal portion and the conductor portion; A signal processing IC is disposed on a second side opposite to the first side of the conductor portion, has a circuit surface, and at least one magnetoelectric conversion unit is disposed on the circuit surface to process the signal output from the at least one magnetoelectric conversion unit; The second lead frame includes a second terminal portion that outputs a signal from the signal processing IC; and The sealing portion utilizes molding resin to seal the at least one magnetoelectric conversion part, the conductor part, the signal processing IC, and a portion of the second lead frame. Let T be the shortest distance from the first side exposed from the first terminal portion of the seal to the second lead frame or the signal processing IC. ds When the relative permittivity of the molding resin is set to ε, the following conditions are met: 523×T ds -1 ×ε 0.08 <400。 2. The current sensor according to claim 1, wherein, T ds It is 1.6mm or more.

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

4. The current sensor according to claim 3, wherein, The shortest distance T ds It is the distance between the first side of the sealing portion and the retaining portion.

5. A current sensor, comprising: At least one magnetoelectric conversion unit; The first lead frame includes a first terminal portion and a conductor portion connected to the first terminal portion, wherein a measuring current measured by the at least one magnetoelectric conversion portion flows through the first terminal portion and the conductor portion; A signal processing IC is disposed on a second side opposite to the first side of the conductor portion, has a circuit surface, and at least one magnetoelectric conversion unit is disposed on the circuit surface to process the signal output from the at least one magnetoelectric conversion unit; The second lead frame includes a second terminal portion that outputs a signal from the signal processing IC; and The sealing portion utilizes molding resin to seal the at least one magnetoelectric conversion part, the conductor part, the signal processing IC, and a portion of the second lead frame. In the signal processing IC, the second surface of the conductor portion is designated as the first surface of the signal processing IC, and the surface opposite to the first surface of the signal processing IC is designated as the second surface. In the sealing portion, the surface opposite to the first surface of the conductor portion is designated as the first surface of the sealing portion, the surface opposite to the second surface of the conductor portion is designated as the second surface of the sealing portion, and the surface of the first terminal portion of the conductor portion that is exposed is designated as the first side surface. Let T be the distance between the portion of the first side of the sealing portion closest to the sealing portion in the second surface of the signal processing IC or the second surface of the conductor portion. b When the relative permittivity of the molding resin is set to ε, the following conditions are met: 470×T b -1 ×ε 0.08 <400。 6. The current sensor according to claim 5, wherein, T b It is 1.35mm or more.

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

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 retaining portion from the second surface of the sealing portion.

9. A current sensor, comprising: At least one magnetoelectric conversion unit; The first lead frame includes a first terminal portion and a conductor portion connected to the first terminal portion, wherein a measuring current measured by the at least one magnetoelectric conversion portion flows through the first terminal portion and the conductor portion; A signal processing IC is disposed on a second side opposite to the first side of the conductor portion, has a circuit surface, and at least one magnetoelectric conversion unit is disposed on the circuit surface to process the signal output from the at least one magnetoelectric conversion unit; The second lead frame includes a second terminal portion that outputs a signal from the signal processing IC; and The sealing portion utilizes molding resin to seal the at least one magnetoelectric conversion part, the conductor part, the signal processing IC, and a portion of the second lead frame. In the sealing portion, the surface opposite to the first surface of the conductor portion is designated as the first surface of the sealing portion, and the exposed surface of the other part of the second lead frame is designated as the second side surface. Let T be the distance between the portion of the first surface of the conductor that is closest to the second side surface of the sealing portion and the first surface of the sealing portion opposite to the first surface of the conductor. t When the relative permittivity of the molding resin is set to ε, the following conditions are met: 280×T t -0.2 ×ε 0.12 <400。 10. The current sensor according to claim 9, wherein, Let T be the shortest distance from the first side exposed from the first terminal portion of the seal to the second lead frame or the signal processing IC. ds In the case that, it still meets 523×T ds -1 ×ε 0.08 <400。 11. The current sensor according to claim 9, wherein, In the signal processing IC, the second surface of the conductor portion is designated as the first surface of the signal processing IC, and the surface opposite to the first surface of the signal processing IC is designated as the second surface. In the sealing portion, the surface opposite to the first surface of the conductor portion is designated as the first surface of the sealing portion, the surface opposite to the second surface of the conductor portion is designated as the second surface of the sealing portion, and the surface of the first terminal portion of the conductor portion that is exposed is designated as the first side surface. Let T be the distance between the portion of the first side of the sealing portion closest to the sealing portion in the second surface of the signal processing IC or the second surface of the conductor portion. b At that time, it also satisfied 470×T b -1 ×ε 0.08 <400。 12. The current sensor according to claim 9, wherein, In the signal processing IC, the second surface of the conductor portion is designated as the first surface of the signal processing IC, and the surface opposite to the first surface of the signal processing IC is designated as the second surface. In the sealing portion, the surface opposite to the first surface of the conductor portion is designated as the first surface of the sealing portion, the surface opposite to the second surface of the conductor portion is designated as the second surface of the sealing portion, and the surface of the first terminal portion of the conductor portion that is exposed is designated as the first side surface. Let T be the shortest distance from the first side of the seal to the second lead frame or the signal processing IC. ds Let T be the distance between the portion of the first side closest to the seal on the second surface of the signal processing IC and the second surface of the seal. b In the case that, it still meets 523×T ds -1 ×ε 0.08 <400 and 470×T b -1 ×ε 0.08 <400.

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

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

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

16. The current sensor according to any one of claims 1 to 13, wherein, The signal processing IC has the circuit surface and the at least one magnetoelectric conversion unit built into it.

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

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