Current detection device

Abstract

Provided is a structure for achieving higher current detection accuracy when a shunt resistor is clamped and connected by a plate-shaped wiring structure such as a bus bar or a lead frame. A current detection device includes: a stacked structure resistor including: a plate-shaped first electrode and a plate-shaped second electrode; the plate-shaped resistor body is arranged between the first electrode and the second electrode; the plate-shaped first conductor and the plate-shaped second conductor are used for current to be measured to flow through and are connected with the resistor. The first conductor is connected with the first electrode, and the second conductor is connected with the second electrode. The resistor is arranged between the first conductor and the second conductor in a stacked mode. One surface of the first conductor is provided with a first insulating layer and a first voltage detection pattern, and the first voltage detection pattern is arranged through the first insulating layer and is used for transmitting a voltage signal.

Description

Technical Field

[0001] This invention relates to a current detection device. Background Technology

[0002] In recent years, with the increasing current used in electronic devices, the development of modules that utilize power semiconductors for power conversion and control has become increasingly popular; these modules are known as power modules. Power modules increasingly utilize high-heat-dissipation substrates that allow for large current flow, such as ceramic substrates formed by directly bonding copper to an alumina substrate, also known as DBC substrates. Alternatively, power semiconductors, shunt resistors, and other components can be directly mounted on board-shaped wiring structures (busbars or lead frames) made of copper plates or similar materials.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Patent Application with Publication No. JP2001-358283

[0006] Patent Document 2: Patent Application with Publication No. JP2022-066642 Summary of the Invention

[0007] The problem to be solved by this invention

[0008] The purpose of the shunt resistor for current sensing described in Patent Document 1 is to improve heat dissipation and reliability, and to reduce wiring length. However, such shunt resistors require multiple bonding leads for connection in high-current applications, making them unsuitable for such uses.

[0009] For this reason, in order to enable such vertical shunt resistors to be used in high-current applications, Patent Document 2 proposes surface mounting with L-shaped electrode components. Patent Document 2 describes a method for extracting voltage signals via bonding leads in such a structure.

[0010] However, to achieve the detection of larger currents, increasing research focuses on connecting vertical shunt resistors using board-like wiring structures such as busbars and lead frames. In this case, the challenge lies in how the voltage signal extraction method and its connection to the control circuit board can meet the current detection accuracy requirements.

[0011] To address the aforementioned problems, the present invention aims to provide a structure for achieving higher current detection accuracy when a shunt resistor is clamped and connected using a plate-like wiring structure such as a busbar or lead frame.

[0012] Problem Solving Methods

[0013] In one embodiment, the current detection device of the present invention includes:

[0014] A resistor having a stacked structure includes: a plate-shaped first electrode and a second electrode; and a plate-shaped resistive body disposed between the first electrode and the second electrode; and

[0015] A plate-shaped first conductor and a second conductor, through which the current to be measured flows and are connected to the resistor.

[0016] The first conductor is connected to the first electrode.

[0017] The second conductor is connected to the second electrode.

[0018] The resistors are stacked between the first conductor and the second conductor.

[0019] A first insulating layer and a first voltage detection pattern are disposed on one side of the first conductor. The first voltage detection pattern is disposed through the first insulating layer and is used to transmit voltage signals.

[0020] In one embodiment, one end of the first voltage detection pattern is connected to the first conductor.

[0021] In one embodiment, one end of the first voltage detection pattern is connected to the first electrode.

[0022] In one embodiment, the first conductor further includes a second voltage detection pattern disposed through the first insulating layer and used to transmit voltage signals.

[0023] In one embodiment,

[0024] The current detection device also includes a plate-shaped voltage connection terminal for detecting voltage.

[0025] The voltage connection terminal includes a flat portion and a connection terminal portion formed by a portion extending from the side.

[0026] The flat portion of the voltage connection terminal is stacked between the second electrode and the second conductor.

[0027] The connection terminal is connected to one end of the second voltage detection pattern.

[0028] In one embodiment,

[0029] The first insulating layer is flexible.

[0030] The first insulating layer includes a bent extension.

[0031] One end of the second voltage detection pattern is disposed on the extension of the first insulating layer.

[0032] One end of the second voltage detection pattern is connected to the second conductor.

[0033] In one embodiment,

[0034] The first conductor has a through hole, and the projection of the through hole along the stacking direction overlaps on the first electrode.

[0035] The first conductor has a conductor connection portion, which is located between the through hole and the end of the first conductor.

[0036] One end of the first voltage detection pattern is connected to the conductor connection portion of the first conductor.

[0037] In one embodiment,

[0038] The first conductor has a through hole, and the projection of the through hole along the stacking direction overlaps on the first electrode.

[0039] The first electrode includes an exposed portion exposed in the via.

[0040] One end of the first voltage detection pattern is connected to the exposed portion of the first electrode.

[0041] The first conductor also includes a second insulating layer.

[0042] Except for a portion of the first voltage detection pattern, the first insulating layer and the first voltage detection pattern are covered by the second insulating layer.

[0043] A through-hole is formed in the first insulating layer and the second insulating layer, extending along the stacking direction to the first conductor.

[0044] The first electrode is connected to the first conductor through the via.

[0045] Invention Effects

[0046] In structures that clamp and connect vertical shunt resistors using plate-like wiring structures such as busbars and lead frames, the current detection device of the present invention is a simplified structure. It not only has a voltage signal output structure that can achieve high-precision voltage detection, but is also easy to connect to a control circuit board.

[0047] Furthermore, the shunt resistor in the current detection device of the present invention has better heat dissipation and can still achieve excellent detection accuracy even in high current conditions. Attached Figure Description

[0048] Figure 1This is a perspective view illustrating the structure of resistor 10 in Embodiment 1 of the present invention.

[0049] Figure 2 This is a side view illustrating the structure of the current detection device 100 in Example 1.

[0050] Figure 3 This is a perspective view of the DBC substrate 20 in Example 1.

[0051] Figure 4 This is a side view illustrating the structure of the current detection device 100 in Embodiment 2.

[0052] Figure 5 This is a perspective view illustrating the structure of the current detection device 100 in Example 2.

[0053] Figure 6 This is a bottom view of the busbar 23 in Example 2.

[0054] Figure 7 This is a perspective view of the copper clip 60 in Example 2.

[0055] Figure 8 This is a side view illustrating the structure of the current detection device 100 in Example 3.

[0056] Figure 9 This is a perspective view illustrating the structure of the current detection device 100 in Example 3.

[0057] Figure 10 This is a bottom view of the busbar 23 in Example 3.

[0058] Figure 11 This is a side view illustrating the structure of the current detection device 100 in Example 4.

[0059] Figure 12 This is a perspective view illustrating the structure of the current detection device 100 in Example 4.

[0060] Figure 13 This is a bottom view of the busbar 23 in Example 4.

[0061] Figure 14 This is a side view illustrating the structure of the current detection device 100 in Example 5.

[0062] Figure 15 This is a bottom view illustrating the structure of the current detection device 100 in Example 5.

[0063] Figure 16 This is a side view illustrating the structure of the current detection device 100 in Example 6.

[0064] Figure 17 This is a perspective view of the copper clip 60 in Example 6.

[0065] Figure 18 As shown Figure 16 Part of the top surface.

[0066] Figure 19 This is a side view illustrating the structure of the current detection device 100 in Example 7.

[0067] Figure 20 As shown Figure 19 Part of the top surface.

[0068] Figure 21 This is an illustrative structural side view of the current detection device 100 in an alternative embodiment of Example 7.

[0069] Figure 22 As shown Figure 21 Part of the top surface.

[0070] Figure 23 This is a side view illustrating the structure of the current detection device 100 in Example 8.

[0071] Figure 24 As shown Figure 23 Part of the top surface.

[0072] Figure Labels

[0073] 10 resistor

[0074] 11 resistors

[0075] 12 First Electrode

[0076] 12a Exposed Part

[0077] 13 Second Electrode

[0078] 20DBC substrate

[0079] 21 copper coins

[0080] 21a Bottom exposed surface

[0081] 22, 23 busbars

[0082] 23a through hole

[0083] 23b Conductor Connection Part

[0084] 24 copper frame

[0085] 31 First Insulation Layer

[0086] 32 Second Insulation Layer

[0087] 33 via

[0088] 34 Flexible substrate (first insulating layer)

[0089] 34a via

[0090] 34b extension

[0091] 34c via

[0092] 41 First voltage detection pattern

[0093] 41a Electrode Connection Part

[0094] 41b voltage lead section

[0095] 41c busbar connection section

[0096] 41d lead connection part

[0097] 42 Second voltage detection pattern

[0098] 42a Connection Terminal Connection Part

[0099] 42b copper frame connection part

[0100] 50 control circuit

[0101] Route 51

[0102] Route 52

[0103] 53, 54, 55, 56 bond wires

[0104] 60 copper clip (voltage connection terminal)

[0105] 60a flat section

[0106] 60b connector connection part

[0107] 60c extension

[0108] 60d insulation treatment section

[0109] 100 Current Detection Device Detailed Implementation

[0110] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0111] Example 1

[0112] Figure 1 This is a perspective view illustrating the structure of resistor 10 in Embodiment 1 of the present invention. The current detection device includes resistor 10.

[0113] Resistor 10 is a stacked resistor, including a plate-shaped first electrode 12 and a second electrode 13, and a plate-shaped resistive element 11 disposed between the first electrode 12 and the second electrode 13. Resistor 10 is, for example, a resistor for current sensing, or a shunt resistor. Resistor 10 may be particularly a vertical shunt resistor. Although the resistive element 11 is in... Figure 1 The example is formed as a square or rectangle, but its shape can be designed arbitrarily.

[0114] The materials for the first electrode 12 and the second electrode 13 are, for example, high-conductivity metals such as copper. The material for the resistor 11 is, for example, a copper-nickel alloy, a copper-manganese alloy, a nickel-chromium alloy, or a metal-containing composite material. The dimensions of the resistor 10 are, for example, 5mm × 5mm × 0.5mm thick. The thickness of both the first electrode 12 and the second electrode 13 is, for example, 0.1mm. The thickness of the resistor 11 is, for example, 0.3mm.

[0115] Figure 1 Only one example of resistor 10 is shown. Other structures may also be used, such as the resistor for current sensing disclosed in patent application publication number JP2018-170478.

[0116] Figure 2 This is a side view illustrating the structure of a current sensing device 100. The current sensing device 100 includes a resistor 10, a direct bonded copper (DBC) substrate 20, and a busbar 22 (second conductor). Figure 2 Only a cross-section of the DBC substrate 20 is shown in the image. Figure 3 This is a three-dimensional view of the DBC substrate 20.

[0117] The DBC substrate 20 includes a copper plate 21 (first conductor). The copper plate 21 is a plate-shaped conductor through which the current to be measured flows. The copper plate 21 is connected to a resistor 10 (particularly to a first electrode 12). The thickness of the copper plate 21 is, for example, at its thinnest point (e.g., Figure 2 The portion other than the via 33 shown below is within the range of 0.3mm to 2.0mm.

[0118] Busbar 22 is a plate-shaped conductor through which the current to be measured flows. Busbar 22 is connected to resistor 10 (particularly to the second electrode 13). Resistor 10 is stacked between copper plate 21 and busbar 22. The thickness of busbar 22 is, for example, 0.3 mm or more, specifically, 0.5 mm.

[0119] In the DBC substrate 20, a first insulating layer 31, a second insulating layer 32, and a first voltage detection pattern 41 are disposed on one side of the copper plate 21. The first insulating layer 31 is made of, for example, silicon nitride, aluminum nitride, aluminum oxide, zirconium oxide, etc. The thickness of the first insulating layer 31 is, for example, in the range of 0.1 mm to 1 mm, specifically, 0.3 mm. The second insulating layer 32 is made of, for example, solder resist. The thickness of the second insulating layer 32 is, for example, in the range of 10 μm to 50 μm. The first voltage detection pattern 41 is a pattern for transmitting voltage signals and is disposed on the copper plate 21 through the first insulating layer 31. The first voltage detection pattern 41 is made of, for example, copper foil, and has a thickness of, for example, 35 μm.

[0120] A via 33 is formed in the first insulating layer 31 and the second insulating layer 32, extending through the stacking direction and reaching the copper plate 21. The bottom exposed surface 21a of the copper plate 21 is exposed outside the first insulating layer 31 and the second insulating layer 32. The bottom exposed surface 21a is bonded to the first electrode 12. In this way, the copper plate 21 is connected to the first electrode 12 through the via 33.

[0121] Except for a portion of the first voltage detection pattern 41, the first insulating layer 31 and the first voltage detection pattern 41 are covered by the second insulating layer 32. Figure 2 and Figure 3 In the example, the electrode connection portion 41a and the voltage lead-out portion 41b of the first voltage detection pattern 41 are exposed, while the rest are covered by the second insulating layer 32. One end of the first voltage detection pattern 41 (i.e., the electrode connection portion 41a) is connected to the top surface of the first electrode 12.

[0122] In this specification, "one end" refers, for example, to the portion including the end in the longitudinal direction. For example, in Figure 2 In this example, one end forming the electrode connection portion 41a includes the longitudinal end of the first voltage detection pattern 41. However, in other examples, strictly speaking, "one end" may not include the longitudinal end, but rather the region near the longitudinal end.

[0123] Alternatively, a structure can be adopted in which the voltage lead-out portion 41b is not exposed from the second insulating layer 32 (for example, it can be on the DBC substrate 20 where it is not exposed). Figure 2 and Figure 3 The opposite end is exposed as shown in the image.

[0124] The connection between the first electrode 12 and the copper plate 21, the connection between the first electrode 12 and the first voltage detection pattern 41, and the connection between the second electrode 13 and the busbar 22 are achieved, for example, by brazing or welding, low-temperature sintering, or other methods.

[0125] In this way, the current can flow into the resistor 10 through the thick copper pattern formed by the copper plate 21 on the surface of the DBC substrate 20, and the voltage can be drawn out from the top surface of the resistor 10 through the first voltage detection pattern 41 on the inner surface of the DBC substrate 20.

[0126] Figure 2 The diagram schematically illustrates the connection between the current detection device 100 and the control circuit 50. The control circuit 50 is connected to the current detection device 100, for example, via lines 51 and 52. Lines 51 and 52 are, for example, bonding wires. Figure 2 In the example, line 51 is connected to the voltage lead-out portion 41b of the first voltage detection pattern 41 and the control circuit 50, and line 52 is connected to the busbar 22 and the control circuit 50. In this way, the voltage signal between the top and bottom surfaces of the resistor 10 (i.e., between the first electrode 12 and the second electrode 13) can be provided to the control circuit 50.

[0127] With the above-described structure, higher accuracy current detection can be achieved. For example, since the connection points between lines 51 and 52 and the current detection device 100 are structures that can ensure a certain surface area, it is easy to achieve a suitable connection method that can improve accuracy.

[0128] Example 2

[0129] Figure 4 and Figure 5 The diagram shows an example structure of the current detection device 100 in Embodiment 2. Wherein, Figure 4 This is a side view. Figure 5 This is a perspective view of one side of the bottom surface. Hereinafter, Embodiment 2 will be described, and the commonalities between it and Embodiment 1 will sometimes be omitted.

[0130] The current detection device 100 replaces Example 1 with busbar 23 (first conductor). Figure 2 The DBC substrate 20 in the circuit is replaced with a copper frame 24 (second conductor) instead of a busbar 22. The thickness of the copper frame 24 is, for example, 0.1 mm or more, specifically, 0.5 mm.

[0131] Figure 6 This is a bottom view of busbar 23. (Example) Figures 4 to 6 As shown, the busbar 23 includes a first insulating layer 31 disposed on one of its surfaces. The first insulating layer 31 is, for example, made of a highly heat-resistant material (polyimide, epoxy resin, etc.). The thickness of the first insulating layer 31 is, for example, in the range of 20 μm to 100 μm.

[0132] Busbar 23 also includes a first voltage detection pattern 41 disposed on the same side surface as the first insulating layer 31 and disposed through the first insulating layer 31. One end of the first voltage detection pattern 41 (i.e., the busbar connection portion 41c) is connected to the busbar 23. Busbar 23 also includes a second voltage detection pattern 42 disposed on the same side surface as the first insulating layer 31 and disposed through the first insulating layer 31. The second voltage detection pattern 42 is a pattern used for transmitting voltage signals.

[0133] The current detection device 100 also includes a plate-shaped copper clip 60 (voltage connection terminal) for detecting voltage. Figure 7 This is a perspective view of one side of the top surface of the copper clip 60. The thickness of the copper clip 60 is, for example, in the range of 0.1mm to 0.3mm, specifically 0.1mm.

[0134] The copper clip 60 includes a flat portion 60a and a connecting end portion 60b formed by a portion extending from the side. The flat portion 60a is stacked between the second electrode 13 of the resistor 10 and the copper frame 24. The connecting end portion 60b is connected to one end (connecting end portion 42a) of the second voltage detection pattern 42.

[0135] With the above configuration, the first electrode 12 of resistor 10 is connected to the first voltage detection pattern 41 via busbar 23, and the second electrode 13 is connected to the second voltage detection pattern 42 via copper clip 60. Although the control circuit is not specifically shown in the figure, the voltage is led out to the control circuit via the first voltage detection pattern 41 and the second voltage detection pattern 42. In this way, the output voltage of resistor 10 can be provided to the control circuit with good accuracy.

[0136] Example 3

[0137] In Example 3, the first insulating layer in Example 2 is replaced with a flexible first insulating layer. Example 3 will be described below, and its commonalities with Examples 1 or 2 will sometimes be omitted.

[0138] Figure 8 and Figure 9 The diagram shows an example structure of the current detection device 100 in Embodiment 3. Wherein, Figure 8 This is a side view (partial cross-sectional view). Figure 9 This is a three-dimensional view of one side of the bottom surface. Furthermore, Figure 10 This is a bottom view of busbar 23.

[0139] The current detection device 100 will implement Example 2 ( Figures 4 to 6The first insulating layer 31 in the substrate is replaced with an insulating flexible substrate 34. The thickness of the flexible substrate 34 is, for example, in the range of 20 μm to 80 μm. If the thickness is less than 20 μm, the flexible substrate 34 will be difficult to handle because the material is too soft. If the thickness is more than 100 μm, the flexible substrate 34 will be too rigid and lack flexibility.

[0140] like Figure 8 As shown, a through-hole 34a is formed in the flexible substrate 34. One end of the first voltage detection pattern 41 is exposed outside the inner surface of the flexible substrate 34 (i.e., the side opposite to the side where the first voltage detection pattern 41 is provided) to form a busbar connection portion 41c. The busbar connection portion 41c is connected to the busbar 23 through the through-hole 34a. This connection is achieved, for example, by brazing or welding, low-temperature sintering, etc.

[0141] In this way, voltage can be extracted through the first voltage detection pattern 41 and the second voltage detection pattern 42.

[0142] Example 4

[0143] In Example 4, the first voltage detection pattern 41 in Example 3 is connected by bonding leads. Hereinafter, Example 4 will be described, and the commonalities with Examples 1 to 3 will sometimes be omitted.

[0144] Figure 11 and Figure 12 The diagram shows an example structure of the current detection device 100 in Embodiment 4. Wherein, Figure 11 This is a side view. Figure 12 This is a three-dimensional view of one side of the bottom surface. Furthermore, Figure 13 This is a bottom view of busbar 23.

[0145] One end of the first voltage detection pattern 41 (lead connection portion 41d) is connected to the busbar 23 via a bonding lead 53. The material of the bonding lead 53 is, for example, gold, silver, copper, aluminum, etc.

[0146] Example 5

[0147] Example 5 omits the copper clip 60 from Example 3 and provides an extension on the flexible substrate 34. Hereinafter, Example 5 will be described, and the commonalities with Examples 1 to 4 will sometimes be omitted.

[0148] Figure 14 and Figure 15 The diagram shows an example structure of the current detection device 100 in Embodiment 5. Wherein, Figure 14 This is a side view (partial cross-sectional view). Figure 15 This is a bottom view.

[0149] As described above, the flexible substrate 34 is flexible. The flexible substrate 34 also includes a bent extension 34b. In this embodiment, the extension 34b extends from the busbar 23 toward the copper frame 24 at an end of the flexible substrate 34 (e.g., the end of the second voltage detection pattern 42 along its length). One end of the second voltage detection pattern 42, i.e., the copper frame connection portion 42b, is provided on the extension 34b. The copper frame connection portion 42b is connected to the copper frame 24.

[0150] Thus, by extending the flexible substrate 34, a direct connection with the copper frame 24 (or busbar) can be achieved, and the copper clip 60 is omitted.

[0151] Example 6

[0152] In Example 6, the flexible substrate 34 from Example 3 is disposed on the opposite side of the busbar 23. Hereinafter, Example 6 will be described, and the commonalities with Examples 1 to 5 will sometimes be omitted.

[0153] Figure 16 This is a side view (partial cross-sectional view) illustrating the structure of the current detection device 100 in Example 6. Figure 17 This is a three-dimensional view of one side of the bottom surface of the copper clip 60. Figure 18 As shown Figure 16 Part of the top surface.

[0154] In Example 3 (see Figure 8 In the figure (etc.), the flexible substrate 34 is disposed on the surface of the busbar 23 on one side of the resistor 10. However, in this embodiment, the flexible substrate 34 is disposed on the surface of the busbar 23 on the opposite side of the resistor 10. At the same time, the first voltage detection pattern 41 and the second voltage detection pattern 42 are still disposed on the surface of the busbar 23 on the opposite side of the resistor 10.

[0155] The busbar 23 has a through-hole 23a extending through the busbar 23 along the stacking direction. The copper clip 60 includes an extension 60c (see...). Figure 17 The extension 60c passes through the through hole 23a and extends to the opposite side of the busbar 23 (i.e., the side where the second voltage detection pattern 42 is provided). To avoid a short circuit between the copper clip 60 and the busbar 23, the extension direction of the extension 60c is preferably parallel to the stacking direction (that is, perpendicular to the flat portion 60a). At least the portion of the extension 60c provided within the through hole 23a is preferably insulated from its surroundings to form an insulating portion 60d. The insulation is achieved, for example, by coating with a material such as epoxy resin.

[0156] The copper clip 60 is connected to the connection end portion 42a of the second voltage detection pattern 42 at its distal end of extension 60c (i.e., connection end portion 60b) via solder 70. Thus, the first electrode 12 of the resistor 10 is connected via the busbar 23 and the busbar connection portion 41c (see...). Figure 18 This figure is similar to that of Example 3. Figure 8 (As shown in the diagram) is connected to the first voltage detection pattern 41, and the second electrode 13 is connected to the second voltage detection pattern 42 through the copper clip 60 and solder 70.

[0157] With the above structure, the busbar 23 can be assembled with the resistor 10, the copper frame 24 and the copper clip 60 in the same direction, thereby improving the efficiency of the assembly work.

[0158] Example 7

[0159] In Example 7, a through-hole is provided in the busbar 23 of Example 6, and a bonding wire is used for connection. Example 7 will be described below; the common parts with Examples 1 to 6 will sometimes be omitted.

[0160] Figure 19 This is a side view (partial cross-sectional view) illustrating the structure of the current detection device 100 in Example 7. Figure 20 As shown Figure 19 Part of the top surface.

[0161] A through-hole 23a is provided within the busbar 23. The through-hole 23a is provided in the busbar 23 such that its projection along the stacking direction overlaps with that of the first electrode 12. The first electrode 12 includes an exposed portion 12a exposed through the through-hole 23a. The connection between the busbar 23 and the resistor 10 (especially with the first electrode 12) can be achieved by bonding such as brazing or low-temperature sintering, but bonding achieved by ultrasonic welding is preferred.

[0162] A conductor connection portion 23b is provided on the busbar 23, which is located between the through hole 23a and the end of the busbar 23. One end of the first voltage detection pattern 41 (i.e., the lead connection portion 41d) is connected to the conductor connection portion 23b of the busbar 23 via a bonding lead 54. The bonding lead 54 crosses over the through hole 23a, connecting the lead connection portion 41d and the conductor connection portion 23b.

[0163] At the end of the busbar 23, the copper clip 60 extends further than the busbar 23, and has an extension 60c at the end extending beyond the busbar 23 along its length (for the copper clip 60, Figure 20 Only its extension 60c is shown in the diagram. The connection portion 42a of the second voltage detection pattern 42 is connected to the extension 60c via a bonding lead 55.

[0164] The temperature coefficient of resistance (TCR) of the current detection device 100 can be adjusted by controlling the positional relationship between the through hole 23a formed in the busbar 23, the resistor 10, and the bonding lead 54.

[0165] Figure 21 This is a side view (partial cross-sectional view) of an exemplary structure of the current detection device 100 in an alternative embodiment of Example 7. Figure 22 As shown Figure 21 Part of the top surface.

[0166] In this alternative embodiment, bonding lead 56 replaces bonding lead 54 in embodiment 7. Bonding lead 56 is connected to the exposed portion 12a of the first electrode 12, rather than to the busbar 23. Thus, one end of the first voltage detection pattern 41 (i.e., the lead connection portion 41d) can be connected to the exposed portion 12a of the first electrode 12 via bonding lead 56.

[0167] The temperature coefficient of resistance (TCR) of the current detection device 100 can be adjusted by controlling the positional relationship between the through hole 23a formed in the busbar 23, the resistor 10, and the bonding lead 56.

[0168] Example 8

[0169] Similar to Embodiment 5, Embodiment 8 omits the copper clip 60 found in Embodiments 6 or 7, and provides an extension 34b on the flexible substrate 34. Embodiment 8 will be described below, and its commonalities with Embodiments 1 to 7 will sometimes be omitted.

[0170] Figure 23 This is a side view (partial cross-sectional view) illustrating the structure of the current detection device 100 in Example 8. Figure 24 As shown Figure 23 Part of the top surface.

[0171] In this embodiment, the extension 34b extends from the busbar 23 toward the copper frame 24 at the end of the flexible substrate 34 (such as the end of the second voltage detection pattern 42 in the longitudinal direction).

[0172] The extension 34b has a via 34c formed along the stacking direction. One end of the second voltage detection pattern 42 (i.e., the copper frame connecting portion 42b) is connected to the top surface of the copper frame 24 through the via 34c.

[0173] Thus, by extending the flexible substrate 34 portion outward, a direct connection with the copper frame 24 (or busbar) can be achieved, eliminating the need for the copper clip 60.

Claims

1. A current detection device, characterized in that, include: A resistor having a stacked structure, the resistor comprising: a plate-shaped first electrode, a plate-shaped second electrode, and a plate-shaped resistive element disposed between the first electrode and the second electrode; and A first plate-shaped conductor and a second plate-shaped conductor are provided for the current to be measured to flow through and are connected to the resistor. The first conductor is connected to the first electrode. The second conductor is connected to the second electrode. The resistors are stacked between the first conductor and the second conductor. A first insulating layer and a first voltage detection pattern are disposed on one side of the first conductor. The first voltage detection pattern is disposed through the first insulating layer and is used to transmit voltage signals.

2. The current detection device as described in claim 1, characterized in that, One end of the first voltage detection pattern is connected to the first conductor.

3. The current detection device as described in claim 1, characterized in that, One end of the first voltage detection pattern is connected to the first electrode.

4. The current detection device as described in claim 2 or 3, characterized in that, The first conductor further includes a second voltage detection pattern disposed through the first insulating layer and used to transmit voltage signals.

5. The current detection device as described in claim 4, characterized in that, The current detection device also includes a plate-shaped voltage connection terminal for detecting voltage. The voltage connection terminal includes a flat portion and a connection terminal portion formed by a portion extending from the side. The flat portion of the voltage connection terminal is stacked and connected between the second electrode and the second conductor. The connection terminal is connected to one end of the second voltage detection pattern.

6. The current detection device as described in claim 4, characterized in that, The first insulating layer is flexible. The first insulating layer includes a bent extension. One end of the second voltage detection pattern is disposed on the extension of the first insulating layer. One end of the second voltage detection pattern is connected to the second conductor.

7. The current detection device as described in claim 2, characterized in that, In the first conductor, a through hole is provided in the region overlapping with the first electrode when viewed from the stacking direction. In the first conductor, a conductor connection portion is provided between the through hole and the end of the first conductor. One end of the first voltage detection pattern is connected to the conductor connection portion of the first conductor.

8. The current detection device as described in claim 3, characterized in that, In the first conductor, a through hole is provided in the region overlapping with the first electrode when viewed from the stacking direction. The first electrode includes an exposed portion exposed in the through-hole. One end of the first voltage detection pattern is connected to the exposed portion of the first electrode.

9. The current detection device as described in claim 3, characterized in that, The first conductor also includes a second insulating layer. Except for a portion of the first voltage detection pattern, the first insulating layer and the first voltage detection pattern are covered by the second insulating layer. A through-hole is formed in the first insulating layer and the second insulating layer, extending along the stacking direction and reaching the first conductor. The first electrode is connected to the first conductor through the via.

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