Shunt resistor and method for manufacturing shunt resistor

Abstract

This shunt resistor comprises a resistive element, a first terminal unit, and a second terminal unit. The resistive element has a first end and a second end that is the end opposite to the first end in a second direction orthogonal to a first direction that is the thickness direction of the resistive element, and also has a third end and a fourth end that is the end opposite to the third end in a third direction orthogonal to the first and second directions. The first terminal unit and the second terminal unit are respectively joined to the first end and the second end. A first slit is formed in the third end. Each of the first terminal unit and the second terminal unit has a fifth end that is the end on the resistive-element side, and a sixth end that is the end on the opposite side to the fifth end. A second slit extending along the second direction facing the fifth-end side is formed in the sixth end. The third-direction position of the second slit is closer to the third end than the third-direction center of the resistive element.

Description

Shunt resistor and method for manufacturing the same

[0001] The present disclosure relates to shunt resistors and methods for manufacturing shunt resistors.

[0002] For example, U.S. Patent No. 5,999,085 (Patent Document 1) describes a resistor. The resistor described in Patent Document 1 includes a resistive plate, a first pad, and a second pad. The resistive plate is rectangular in plan view. The resistive plate has a first end and a second end opposite the first end in a second direction perpendicular to a first direction, which is the thickness direction of the resistive plate. The resistive plate has a third end and a fourth end opposite the third end in the second direction perpendicular to the first and second directions. A first slit is formed in the fourth end.

[0003] A first pad and a second pad are bonded to the first end and the second end. Each of the first pad and the second pad has a fifth end that is the end on the resistor plate side and a sixth end that is the end opposite the fifth end. A second slit is formed in the sixth end, extending in the second direction toward the fifth end.

[0004] Each of the first pad and the second pad is divided into a current pad and a sense pad by a second slit. The current flowing through the resistor described in Patent Document 1 is measured by measuring the voltage between the sense pad of the first pad and the sense pad of the second pad. In other words, the resistor described in Patent Document 1 is a shunt resistor. The position of the second slit in the third direction is closer to the third end than the center of the resistor plate in the third direction.

[0005] U.S. Patent No. 5,999,085

[0006] The behavior of the heat generation amount and the temperature coefficient of resistance in the shunt resistor described in Patent Document 1 differs between when the first slit is formed at the third end and when the first slit is formed at the fourth end. More specifically, in the resistor described in Patent Document 1, because the first slit is formed at the fourth end, the increase in the temperature coefficient of resistance is small but the increase in heat generation is large.

[0007] The present disclosure has been made in consideration of the above-described problems of the conventional art. More specifically, the present disclosure provides a shunt resistor that can suppress an increase in the temperature coefficient of resistance while also suppressing an increase in the amount of heat generated.

[0008] The shunt resistor of the present disclosure includes a resistor element, a first terminal portion, and a second terminal portion. The resistor element has a first end and a second end opposite the first end in a second direction perpendicular to a first direction, which is the thickness direction of the resistor element, and a third end and a fourth end opposite the third end in a third direction perpendicular to the first and second directions. A first terminal portion and a second terminal portion are joined to the first end and the second end, respectively. A first slit is formed in the third end. Each of the first terminal portion and the second terminal portion has a fifth end which is an end on the resistor element side and a sixth end which is an end opposite the fifth end. A second slit is formed in the sixth end, extending along the second direction toward the fifth end. The second slit is located closer to the third end than to the center of the resistor element in the third direction.

[0009] The shunt resistor of the present disclosure can suppress an increase in the temperature coefficient of resistance while also suppressing an increase in the amount of heat generated.

[0010] 1 is a perspective view of a shunt resistor 100; a plan view of the shunt resistor 100; a bottom view of the shunt resistor 100; a front view of the shunt resistor 100; manufacturing process diagrams of the shunt resistor 100; a perspective view illustrating a welding process S12; a perspective view illustrating a punching process S131; a perspective view illustrating a bending process S132; a perspective view illustrating a slit forming process S14; a perspective view illustrating a trimming process S2; a perspective view illustrating a slit forming process S14 and a trimming process S2 according to a modified example; a perspective view of a shunt resistor 100A; a graph showing the relationship between the length of a first slit 10e and the surface temperature of the shunt resistor 100 and the surface temperature of the shunt resistor 100A; a graph showing the relationship between the length of a first slit 10e and the temperature coefficient of resistance of the shunt resistor 100 and the temperature coefficient of resistance of the shunt resistor 100A; a graph showing the relationship between the length of a second slit 20c and the temperature coefficient of resistance of the shunt resistor 100. FIG. 1 is a front view of the shunt resistor 100B.

[0011] The details of the embodiments of the present disclosure will be described with reference to the drawings. In the following drawings, the same or corresponding parts are designated by the same reference numerals, and redundant descriptions will not be repeated.

[0012] First Embodiment A shunt resistor (shunt resistor 100) according to a first embodiment will be described below.

[0013] <Configuration of Shunt Resistor 100> The configuration of the shunt resistor 100 will be described below.

[0014] Fig. 1 is a perspective view of the shunt resistor 100. Fig. 2 is a plan view of the shunt resistor 100. Fig. 3 is a bottom view of the shunt resistor 100. Fig. 4 is a front view of the shunt resistor 100. As shown in Figs. 1 to 4, the shunt resistor 100 is a four-terminal shunt resistor. The shunt resistor 100 has a resistive element 10, a first terminal 21, and a second terminal 22.

[0015] The resistor 10 has a flat plate shape. The thickness direction of the resistor 10 is defined as a first direction DR1. The direction perpendicular to the first direction DR1 is defined as a second direction DR2. The direction perpendicular to the first direction DR1 and the second direction DR2 is defined as a third direction DR3. The resistor 10 has, for example, a rectangular shape in a plan view.

[0016] The resistor 10 has a first end 10a and a second end 10b. The first end 10a and the second end 10b are opposite ends of the resistor 10 in the second direction DR2. The second end 10b is the end opposite the first end 10a. The resistor 10 has a third end 10c and a fourth end 10d. The third end 10c and the fourth end 10d are opposite ends of the resistor 10 in the third direction DR3. The fourth end 10d is the end opposite the third end 10c.

[0017] A first slit 10e is formed at the third end 10c. The first slit 10e extends, for example, along the third direction DR3 toward the fourth end 10d. The first slit 10e penetrates the resistor 10 along the first direction DR1.

[0018] The resistor 10 is formed of a conductor. The resistor 10 is formed of, for example, geranine (registered trademark, CuMn7Sn), CuMn3, manganin (registered trademark, CuMn12Ni), NiCrAl, or the like. However, the resistor 10 may be formed of other materials. The constituent material of the resistor 10 may be appropriately selected depending on the required characteristics, such as the resistivity and temperature coefficient of resistance. The thickness of the resistor 10 is preferably 0.4 mm or more. Note that, since increasing the thickness of the resistor 10 requires increasing the thickness of the first terminal 21 and the second terminal 22, taking into account the workability of the first terminal 21 and the second terminal 22, the thickness of the resistor 10 is preferably 0.6 mm or less.

[0019] The first terminal 21 is joined to the first end 10a. The second terminal 22 is joined to the second end 10b. The first terminal 21 and the second terminal 22 are joined to the resistor 10 by, for example, welding. Each of the first terminal 21 and the second terminal 22 has a fifth end 20a and a sixth end 20b. The fifth end 20a is the end on the resistor 10 side. The sixth end 20b is the end opposite the fifth end 20a. A second slit 20c is formed in each of the first terminal 21 and the second terminal 22. The second slit 20c penetrates the first terminal 21 (second terminal 22) along its thickness direction. The width of the first terminal 21 in the third direction DR3 and the width of the second terminal 22 in the third direction DR3 are, for example, equal to the width of the resistor 10 in the third direction DR3.

[0020] The position of the second slit 20c in the third direction DR3 is closer to the third end 10c than the center of the resistor 10 in the third direction DR3. That is, the width of the portion of the first terminal 21 (second terminal 22) on one side of the second slit 20c in the third direction DR3 (upper side in FIG. 3 ) is smaller than the width of the portion of the first terminal 21 (second terminal 22) on the other side of the second slit 20c in the third direction DR3 (lower side in FIG. 3 ). The portion of the first terminal 21 (second terminal 22) on one side of the second slit 20c in the third direction DR3 is the sense terminal of the first terminal 21 (second terminal 22). The shunt resistor 100 detects the value of the current flowing through the shunt resistor 100 based on the value of the voltage between the sense terminal of the first terminal 21 and the sense terminal of the second terminal 22.

[0021] The position of the tip of the first slit 10e in the third direction DR3 preferably overlaps the position of the second slit 20c in the third direction DR3. The position of the tip of the first slit 10e in the third direction DR3 may be closer to the fourth end 10d than the position of the second slit 20c in the third direction DR3. Each of the first terminal 21 and the second terminal 22 is made of a conductor. Each of the first terminal 21 and the second terminal 22 is made of, for example, copper or a copper alloy.

[0022] The resistor 10 has a first surface 10f and a second surface 10g. The first surface 10f and the second surface 10g are end surfaces of the resistor 10 in the first direction DR1. The second surface 10g is the surface opposite the first surface 10f. The first terminal 21 and the second terminal 22 are each bent inward so that the sixth end 20b of the first terminal 21 and the sixth end 20b of the second terminal 22 face each other at a distance in the second direction DR2. The sixth end 20b of the first terminal 21 and the sixth end 20b of the second terminal 22 face each other at a distance from the second surface 10g in the first direction DR1.

[0023] A third slit 10h may be formed in the fourth end 10d. The third slit 10h extends, for example, along the third direction DR3 toward the third end 10c. The length of the third slit 10h in the third direction DR3 is smaller than the length of the first slit 10e in the third direction DR3.

[0024] The temperature coefficient of resistance (TCR) of the shunt resistor 100 is preferably −50 ppm / ° C. or more and 50 ppm / ° C. or less. The temperature coefficient of resistance of the shunt resistor 100 is measured, for example, using an RM3543 manufactured by Hioki E.E. Corporation. The temperature coefficient of resistance of the shunt resistor 100 is measured, for example, in a state where the shunt resistor 100 is mounted on a substrate. This substrate has, for example, a glass epoxy base material with a thickness of 1.6 mm and a copper foil with a thickness of 35 μm arranged on the base material.

[0025] <Method of Manufacturing Shunt Resistor 100> A method of manufacturing the shunt resistor 100 will be described below.

[0026] 5 is a manufacturing process diagram of the shunt resistor 100. As shown in Fig. 5, the manufacturing method of the shunt resistor 100 includes a preparation step S1 and a trimming step S2. The trimming step S2 is performed after the preparation step S1.

[0027] In the preparation process S1, a plurality of shunt resistors 100 are prepared. However, the plurality of shunt resistors 100 prepared in the preparation process S1 do not have third slits 10h formed therein. The preparation process S1 includes a rolling process S11, a welding process S12, a pressing process S13, and a slit forming process S14. The welding process S12 is performed after the rolling process S11. The pressing process S13 is performed after the welding process S12. The slit forming process S14 is performed after the pressing process S13.

[0028] The pressing process S13 includes a punching process S131, a bending process S132, and a singulation process S133. The bending process S132 is performed after the punching process S131. The singulation process S133 is performed after the bending process S132.

[0029] In the rolling step S11, the first plate member 11, the second plate member 23, and the third plate member 24 are rolled to adjust the thicknesses of the first plate member 11, the second plate member 23, and the third plate member 24. At this time, any warping or bending of the first plate member 11, the second plate member 23, and the third plate member 24 is also corrected. The first plate member 11 is made of the same material as the resistor 10, the second plate member 23 is made of the same material as the first terminal portion 21, and the third plate member 24 is made of the same material as the second terminal portion 22. The longitudinal directions of the first plate member 11, the second plate member 23, and the third plate member 24 are aligned along a third direction DR3.

[0030] 6 is a perspective view illustrating the welding step S12. As shown in FIG. 6, in the welding step S12, the second plate member 23 and the third plate member 24 are welded to the first plate member 11. In the welding step S12, first, the first plate member 11, the second plate member 23, and the third plate member 24 are aligned along the second direction DR2. At this time, the first plate member 11 is sandwiched between the second plate member 23 and the third plate member 24.

[0031] Second, the boundary between the first plate member 11 and the second plate member 23 and the boundary between the first plate member 11 and the third plate member 24 are welded. This welding is performed, for example, by scanning the laser L1 along the boundary between the first plate member 11 and the second plate member 23 and the boundary between the first plate member 11 and the third plate member 24.

[0032] In the press step S13, the first plate member 11, the second plate member 23, and the third plate member 24 are subjected to press working.

[0033] 7 is a perspective view illustrating the punching step S131. As shown in FIG. 7, in the punching step S131, first, a plurality of second slits 20c are formed in the second plate member 23 and the third plate member 24. The plurality of second slits 20c are formed so as to be aligned at intervals in the third direction DR3. Second, the second plate member 23 is divided into a plurality of first terminal portions 21, and the third plate member 24 is divided into a plurality of second terminal portions 22.

[0034] 8 is a perspective view illustrating the bending step S132. As shown in FIG. 8, in the bending step S132, the first terminal 21 and the second terminal 22 are bent inward so that the sixth end 20 b of the first terminal 21 and the sixth end 20 b of the second terminal 22 face each other with a gap in between in the second direction DR2. In the singulation step S133, the first plate member 11 is cut to obtain a plurality of shunt resistors 100.

[0035] 9 is a perspective view illustrating the slit forming step S14. As shown in FIG. 9, in the slit forming step S14, a first slit 10e is formed in the third end 10c of each of the plurality of shunt resistors 100. The first slit 10e is formed, for example, by irradiating the resistor 10 with a laser L2. The first slit 10e of each of the plurality of shunt resistors 100 is formed so that its length in the third direction DR3 is constant.

[0036] FIG. 10 is a perspective view illustrating the trimming step S2. As shown in FIG. 10 , in the trimming step S2, third slits 10h are formed in the fourth ends 10d of the shunt resistors 100, thereby adjusting the electrical resistance values ​​of the shunt resistors 100. The lengths of the third slits 10h in the third direction DR3 of the shunt resistors 100 may be different from one another. The third slits 10h are formed, for example, by irradiating the resistor 10 with a laser beam L3. In this manner, the shunt resistor 100 having the structure shown in FIGS. 1 to 4 is manufactured. After the trimming step S2, the surface of the shunt resistor 100 may be cleaned or subjected to an anti-rust treatment.

[0037] 11 is a perspective view illustrating the slit forming step S14 and the trimming step S2 according to a modified example. As shown in FIG. 11, the slit forming step S14 and the trimming step S2 may be performed by pressing between the punching step S131 and the bending step S132. Although not shown, the slit forming step S14 may be performed by pressing between the punching step S131 and the bending step S132.

[0038] <Effects of the Shunt Resistor 100> The effects of the shunt resistor 100 will be described below in comparison with a shunt resistor according to a comparative example. The shunt resistor according to the comparative example is referred to as the shunt resistor 100A. FIG. 12 is a perspective view of the shunt resistor 100A. As shown in FIG. 12, the shunt resistor 100A has a first slit 10e formed at the fourth end 10d and a third slit 10h formed at the third end 10c. Except for this point, the configuration of the shunt resistor 100A is the same as the configuration of the shunt resistor 100.

[0039] Fig. 13 is a graph showing the relationship between the length of the first slit 10e and the surface temperatures of the shunt resistor 100 and the shunt resistor 100A. The graph in Fig. 13 was created based on data measured with 5 W of power applied to the shunt resistor 100 and the shunt resistor 100A. Fig. 14 is a graph showing the relationship between the length of the first slit 10e and the temperature coefficient of resistance of the shunt resistor 100 and the temperature coefficient of resistance of the shunt resistor 100A. As shown in Figs. 13 and 14, the behavior of the heat generation amount and temperature coefficient of resistance of the shunt resistor differs between when the first slit 10e is formed at the third end 10c and when the first slit 10e is formed at the fourth end 10d.

[0040] More specifically, in the shunt resistor 100A in which the first slit 10e is formed at the fourth end 10d, the temperature coefficient of resistance does not increase significantly even if the length of the first slit 10e is increased, but the amount of heat generated increases significantly as the length of the first slit 10e increases. On the other hand, in the shunt resistor 100 in which the first slit 10e is formed at the third end 10c, the amount of heat generated does not increase significantly even if the length of the first slit 10e is increased, but the temperature coefficient of resistance increases significantly as the length of the first slit 10e increases.

[0041] FIG. 15 is a graph showing the relationship between the length of the second slit 20c and the temperature coefficient of resistance of the shunt resistor 100. The graph in FIG. 15 was calculated using computer-aided engineering (CAE) analysis. As shown in FIG. 15, the temperature coefficient of resistance of the shunt resistor 100 changes with the length of the second slit 20c. Therefore, in the shunt resistor 100, an increase in the temperature coefficient of resistance that occurs as the length of the first slit 10e increases can be canceled by adjusting the length of the second slit 20c. Therefore, the shunt resistor 100 can suppress an increase in the temperature coefficient of resistance while also suppressing an increase in the amount of heat generated.

[0042] In the shunt resistor 100A, a third slit 10h is formed at the third end 10c to adjust the electrical resistance. Therefore, in the shunt resistor 100A, the increase in the temperature coefficient of resistance due to the adjustment of the electrical resistance is large. Similarly, in the shunt resistor 100, a third slit 10h is formed to adjust the electrical resistance. However, in the shunt resistor 100, the third slit 10h is formed at the fourth end 10d, so the increase in the temperature coefficient of resistance due to the formation of the third slit 10h is small. Thus, in the shunt resistor 100, it is possible to suppress an increase in the temperature coefficient of resistance even when the electrical resistance is adjusted by forming the third slit 10h.

[0043] The electrical resistance value of the resistor 10 is calculated by multiplying the specific resistance by the width of the resistor 10 by the thickness of the resistor 10 by the length of the resistor 10 in the second direction DR2. Therefore, the electrical resistance value of the resistor 10 can be increased by reducing the thickness of the resistor 10 without forming the first slits 10e. However, reducing the thickness of the resistor 10 increases the amount of heat generated in the resistor 10. In the shunt resistor 100, the thickness of the resistor 10 is preferably 0.4 mm or more, and therefore the amount of heat generated in the shunt resistor 100 is also suppressed from this perspective.

[0044] In the shunt resistor 100, when the first terminal portion 21 and the second terminal portion 22 are bent inward so that the sixth end 20b of the first terminal portion 21 and the sixth end 20b of the second terminal portion 22 face each other with a gap between them, it is possible to reduce the area occupied by the shunt resistor 100 when viewed in a plane.

[0045] Second Embodiment A shunt resistor (shunt resistor 100B) according to a second embodiment will be described below. Here, differences from the shunt resistor 100 will be mainly described, and overlapping descriptions will not be repeated.

[0046] <Configuration of Shunt Resistor 100B> The configuration of the shunt resistor 100B will be described below.

[0047] Fig. 16 is a front view of the shunt resistor 100B. As shown in Fig. 16, the shunt resistor 100B has a resistive element 10, a first terminal 21, and a second terminal 22. Although not shown in Fig. 16, a first slit 10e is formed in the third end 10c, a second slit 20c is formed in the sixth end 20b, and a third slit 10h is formed in the fourth end 10d. In these respects, the configuration of the shunt resistor 100B is common to the configuration of the shunt resistor 100.

[0048] In the shunt resistor 100B, each of the first terminal 21 and the second terminal 22 has a first portion 20d and a second portion 20e. The first portion 20d is a portion of the first terminal 21 (second terminal 22) that is joined to the resistor 10 and includes the fifth end 20a. The second portion 20e is a portion of the first terminal 21 (second terminal 22) that is connected to the first portion 20d from the side opposite the resistor 10 and includes the sixth end 20b.

[0049] The first portion 20d is bent so that the sixth end 20b is farther away from the resistor 10 in the first direction DR1 than the fifth end 20a. In the shunt resistor 100B, the sixth end 20b of the first terminal 21 and the sixth end 20b of the second terminal 22 are respectively located at opposite ends of the shunt resistor 100B in the second direction DR2. That is, in the shunt resistor 100B, the first terminal 21 and the second terminal 22 are bent outward. In these respects, the configuration of the shunt resistor 100B differs from the configuration of the shunt resistor 100.

[0050] <Effects of the Shunt Resistor 100B> The effects of the shunt resistor 100B will be described below.

[0051] In the shunt resistor 100B, the first terminal portion 21 and the second terminal portion 22 are bent outward, so that the shunt resistor 100B can be made lower in height than the shunt resistor 100 in which the first terminal portion 21 and the second terminal portion 22 are bent inward.

[0052] In the shunt resistor 100, when a rotary blade is brought into contact with the resistor 10 to form the first slit 10e and the third slit 10h, there is a risk that the rotary blade will come into contact with the first terminal portion 21 and the second terminal portion 22, which are bent inward, making it difficult to form the first slit 10e and the third slit 10h by cutting using the rotary blade.

[0053] On the other hand, in the shunt resistor 100B, the first terminal 21 and the second terminal 22 are bent outward, so that the first slit 10e and the third slit 10h can be formed by the rotary blade without contacting the first terminal 21 and the second terminal 22. In this way, the shunt resistor 100B allows for greater flexibility in processing in the slit forming step S14 and the trimming step S2 compared to the shunt resistor 100.

[0054] Although the embodiments of the present disclosure have been described above, the above-described embodiments can be modified in various ways. Furthermore, the scope of the present invention is not limited to the above-described embodiments. The scope of the present invention is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims.

[0055] 10 resistor, 10a first end, 10b second end, 10c third end, 10d fourth end, 10e first slit, 10f first surface, 10g second surface, 10h third slit, 11 first plate member, 20a fifth end, 20b sixth end, 20c second slit, 20d first portion, 20e second portion, 21 first terminal portion, 22 second terminal portion, 23 second plate member, 24 third plate member, 100 shunt resistor, 100A shunt resistor, 100B shunt resistor, DR1 first direction, DR2 second direction, DR3 third direction, L1, L2, L3 laser, S1 preparation process, S11 rolling process, S12 welding process, S13 pressing process, S131 punching process, S132 process, S133 Singulation step, S14 slit forming step, S2 trimming step.

Claims

1. A shunt resistor, comprising: A resistor; A first terminal portion and a second terminal portion, the resistor has a first end and a second end opposite to the first end in a second direction perpendicular to a first direction which is a thickness direction of the resistor, and has a third end and a fourth end opposite to the third end in a third direction perpendicular to the first direction and the second direction; The first terminal portion and the second terminal portion are joined to the first end and the second end, respectively; A first slit is formed in the third end, Each of the first terminal portion and the second terminal portion has a fifth end which is an end on the resistor side and a sixth end which is an end opposite to the fifth end, A second slit is formed in the sixth end and extends along the second direction toward the fifth end. A shunt resistor, wherein the position of the second slit in the third direction is closer to the third end than to the center of the resistor in the third direction.

2. The shunt resistor as described in claim 1, wherein the position of the tip of the first slit in the third direction overlaps with the position of the second slit in the third direction or is closer to the fourth end than the position of the second slit in the third direction.

3. a third slit is formed in the fourth end and extends along the third direction toward the third end; The shunt resistor according to claim 1 , wherein a length of the third slit in the third direction is smaller than a length of the first slit in the third direction.

4. The shunt resistor according to claim 1 , wherein the resistor has a thickness of 0.4 mm or more.

5. 2. The shunt resistor according to claim 1, wherein each of the first terminal portion and the second terminal portion is bent inwardly so that the sixth end of the first terminal portion and the sixth end of the second terminal portion face each other with a gap in between in the second direction.

6. each of the first terminal portion and the second terminal portion has a first portion joined to the resistor and including the fifth end, and a second portion connected to the first portion from a side opposite to the resistor and including the sixth end; 2. The shunt resistor of claim 1, wherein the first portion is bent so that the sixth end is farther from the resistor in the first direction than the fifth end and the sixth end is located at an end of the shunt resistor in the first direction.

7. The shunt resistor according to any one of claims 1 to 6, wherein the shunt resistor has a temperature coefficient of resistance of -50 ppm / °C or more and 50 ppm / °C or less.

8. Providing a plurality of shunt resistors; A trimming process is also provided. Each of the plurality of shunt resistors includes a resistor body, a first terminal portion, and a second terminal portion, the resistor has a first end and a second end opposite to the first end in a second direction perpendicular to a first direction which is a thickness direction of the resistor, and has a third end and a fourth end opposite to the third end in a third direction perpendicular to the first direction and the second direction; The first terminal portion and the second terminal portion are joined to the first end and the second end, respectively; A first slit is formed in the third end, Each of the first terminal portion and the second terminal portion has a fifth end which is an end on the resistor side and a sixth end which is an end opposite to the fifth end, A second slit is formed in the sixth end and extends along the second direction toward the fifth end. a position of the second slit in the third direction is closer to the third end than to a center of the resistor in the third direction; In each of the plurality of shunt resistors, the length of the first slit in the second direction is constant, In the trimming step, a third slit is formed in the fourth end of each of the plurality of shunt resistors, thereby adjusting an electrical resistance value of each of the plurality of shunt resistors; A method for manufacturing a shunt resistor, wherein the length of the third slit in the third direction is smaller than the length of the first slit in the third direction.