Shunt resistor and electronic device

Abstract

This disclosure relates to the field of power supply detection technology, and particularly to a shunt resistor and electronic device. The shunt resistor includes: a first shunt bent piece, which forms a first cavity through a bending configuration; a second shunt bent piece, which forms a second cavity through a bending configuration; and a current-conducting piece connected between the first and second shunt bent pieces. The first and second cavities are oriented in the same direction, and current flows sequentially through the first shunt bent piece, the current-conducting piece, and the second shunt bent piece. The shunt resistor of this disclosure helps to reduce or even eliminate the induced electromotive force under conditions of rapid current changes. In metal strip designs, the shunt resistor of this disclosure helps to weaken or even eliminate the influence of parasitic inductance on measurement results, and helps to improve the accuracy of current measurement on the power path.

Description

Technical Field

[0001] This disclosure relates to the field of power supply detection technology, and in particular to a shunt resistor and electronic device. Background Technology

[0002] Shunt resistors are the core components for current sampling in power supply detection systems. By connecting them in series to the power path from the power source to the load, they convert the current signal into a voltage signal, enabling accurate measurement and monitoring of the current.

[0003] In high-frequency current measurement scenarios, such as in high-frequency switching power supply applications, the shunt resistor itself has a significant parasitic inductance effect. The parasitic inductance will generate a corresponding induced voltage superimposed on the voltage drop of the resistive part of the shunt resistor, resulting in distortion of the current detection signal and a decrease in measurement accuracy. Summary of the Invention

[0004] In view of this, the present disclosure provides a shunt resistor and electronic device to help reduce the parasitic inductance of the shunt resistor and improve the accuracy of current measurement on the power path.

[0005] According to one aspect of the embodiments of this disclosure, a shunt resistor is provided, comprising:

[0006] The first diversion bending piece forms a first cavity through a bending configuration;

[0007] The second diversion bending piece forms a second cavity through a bending configuration;

[0008] A flow guide plate, wherein the flow guide plate is connected between the first flow diversion bend plate and the second flow diversion bend plate;

[0009] The first cavity and the second cavity are oriented in the same direction, and the current flows sequentially through the first shunt bending plate, the guide plate and the second shunt bending plate.

[0010] In one possible implementation, the first diversion bend includes:

[0011] First conductive sheet body;

[0012] Second conductive sheet portion;

[0013] The first resistive sheet portion is connected to the first conductive sheet portion at a first connecting edge, and the first resistive sheet portion is connected to the second conductive sheet portion at a second connecting edge. The extending directions of the first connecting edge and the second connecting edge are parallel to each other. Furthermore, a predetermined angle is formed between the first resistive sheet portion and the first conductive sheet portion, and between the first resistive sheet portion and the second conductive sheet portion. The first cavity is formed by the first conductive sheet portion, the first resistive sheet portion, and the second conductive sheet portion.

[0014] The first power supply pin is connected to the side of the first conductive sheet portion away from the first connection edge;

[0015] The side of the second conductive sheet body that is away from the second connecting edge is connected to the flow guide sheet.

[0016] In one possible implementation, the first conductive sheet portion and the second conductive sheet portion are perpendicular to the first resistive sheet portion.

[0017] In one possible implementation, the shunt resistor further includes:

[0018] The first detection connection part is connected to the first resistor sheet body part at the first connection edge;

[0019] The second detection connection part is connected to the first resistor sheet body part at the second connection edge.

[0020] In one possible implementation, the first detection connection includes:

[0021] The first detection connection piece is connected to the first resistor piece at the first connection edge;

[0022] The first detection pin is connected to the side of the first detection connection piece that is away from the first connection edge;

[0023] The second detection connection includes:

[0024] The second detection connection piece is connected to the first resistor piece at the second connection edge;

[0025] The second detection pin is connected to the side of the second detection connection plate that is away from the second connection edge.

[0026] In one possible implementation, the second diversion bend includes:

[0027] Third conductive sheet body;

[0028] Fourth conductive sheet body;

[0029] The second resistive sheet portion is connected to the third conductive sheet portion at a third connecting edge, and the second resistive sheet portion is connected to the fourth conductive sheet portion at a fourth connecting edge. The extending directions of the third connecting edge and the fourth connecting edge are parallel to each other. Furthermore, a predetermined angle is formed between the second resistive sheet portion and the third conductive sheet portion, and between the second resistive sheet portion and the fourth conductive sheet portion. The second cavity is formed by the third conductive sheet portion, the second resistive sheet portion, and the fourth conductive sheet portion.

[0030] The second power supply pin is connected to the side of the fourth conductive sheet portion away from the fourth connection edge;

[0031] The side of the third conductive sheet body that is away from the third connecting edge is connected to the flow guide sheet.

[0032] In one possible implementation, the third conductive sheet portion and the fourth conductive sheet portion are perpendicular to the second resistive sheet portion.

[0033] In one possible implementation, the second resistive sheet portion is a resistive portion, and the third conductive sheet portion and the fourth conductive sheet portion are conductive portions.

[0034] In one possible implementation, the guide vane is located outside the first cavity and the second cavity.

[0035] In one possible implementation, the flow guide is located inside the first cavity and outside the second cavity, and the second flow diversion deflector is located in the first cavity.

[0036] In one possible implementation, the first diversion bending plate, the second diversion bending plate, and the guide plate are integrally formed;

[0037] Alternatively, the first diversion bending plate and the guide plate, as well as the guide plate and the second diversion bending plate, are welded together;

[0038] Alternatively, the flow guide plate is integrally formed with either the first flow diversion bending plate or the second flow diversion bending plate, and is welded to the other of the first flow diversion bending plate and the second flow diversion bending plate.

[0039] According to another aspect of the present disclosure, an electronic device is provided, including a shunt resistor as described in any of the preceding claims.

[0040] As can be seen from the above scheme, the shunt resistor and electronic device disclosed herein utilize the first and second shunt bending pieces to form a first cavity and a second cavity. During the current flow, parasitic induced magnetic fields are generated in the first cavity and the second cavity respectively. When the magnetic flux of the parasitic induced magnetic field generated in the first cavity passes through the second cavity, it cancels the parasitic induced magnetic field generated in the second cavity. Similarly, when the magnetic flux of the parasitic induced magnetic field generated in the second cavity passes through the first cavity, it cancels the parasitic induced magnetic field generated in the first cavity. Thus, the parasitic induced magnetic fields generated by parasitic inductance are mutually canceled between the first cavity and the second cavity, thereby helping to reduce or even eliminate the induced electromotive force under the condition of rapid current change. In the metal strip scheme, the shunt resistor and electronic device disclosed herein help to weaken or even eliminate the influence of parasitic inductance on the measurement results and help to improve the current measurement accuracy on the power path. Attached Figure Description

[0041] Figure 1A This is a first-view structural schematic diagram of a shunt resistor according to an illustrative embodiment;

[0042] Figure 1B This is a second-view structural schematic diagram of a first embodiment of a shunt resistor shown according to an illustrative embodiment;

[0043] Figure 1C This is a third-view structural schematic diagram of a first embodiment of a shunt resistor, shown according to an illustrative embodiment.

[0044] Figure 2A This is a first-view structural schematic diagram of a second embodiment of a shunt resistor, shown according to an illustrative embodiment.

[0045] Figure 2B This is a second-view structural schematic diagram of a second embodiment of a shunt resistor, shown according to an illustrative embodiment;

[0046] Figure 2C This is a second-view structural schematic diagram of a second embodiment of a shunt resistor, shown according to an illustrative embodiment;

[0047] Figure 3 This is a schematic diagram of the principle structure of the shunt resistor according to an embodiment of the present disclosure;

[0048] Figure 4 This is a schematic diagram illustrating the relationship between induced voltage and parasitic inductance at a current change rate of 2000 A / µs, according to an illustrative embodiment.

[0049] Figure 5 This is a schematic diagram of the magnetic flux distribution of the shunt resistor in the first embodiment;

[0050] Figure 6 This is a schematic diagram of the magnetic flux distribution of the shunt resistor in the second embodiment;

[0051] Figure 7 This is a circuit diagram of a shunt resistor used in an embodiment of this disclosure for current measurement.

[0052] Figure 8 This is a schematic diagram illustrating the relationship between the relative error curves of current detection, based on an illustrative embodiment.

[0053] Figure 9 This is a schematic diagram comparing the resistivity-temperature characteristics of manganese copper and copper, according to an illustrative embodiment.

[0054] In the attached diagram, the component names represented by each number are as follows:

[0055] 10. First diversion bending piece;

[0056] 11. First conductive sheet body;

[0057] 12. Second conductive sheet body;

[0058] 13. First resistor body;

[0059] 14. First power supply pin;

[0060] 15. First connecting edge;

[0061] 16. Second connecting edge;

[0062] 20. Second diversion bending piece;

[0063] 21. Third conductive sheet body;

[0064] 22. Fourth conductive sheet body;

[0065] 23. Second resistor body;

[0066] 24. Second power supply pin;

[0067] 25. Third connecting edge;

[0068] 26. Fourth connecting edge;

[0069] 30. Flow deflector;

[0070] 41. First detection connection part;

[0071] 411. First detection connection plate part;

[0072] 412. First detection pin;

[0073] 42. Second detection connection part;

[0074] 421. Second detection connecting piece;

[0075] 422. Second detection pin;

[0076] 100. First cavity;

[0077] 200. Second cavity. Detailed Implementation

[0078] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided with reference to the accompanying drawings and embodiments.

[0079] It should be noted that the terms "first," "second," etc., in the specification, claims, and drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0080] In power path current measurement, the metal strip scheme is a current sampling technique that uses a solid metal strip made of alloy as the resistive element to achieve high-precision detection of large currents. Some metal strip schemes suffer from parasitic inductance. While the parasitic inductance has a slight impact on low-frequency current measurements, in high-speed switching paths, it can generate an induced electromotive force (EMF) that affects the measurement results when the current changes rapidly, thus impacting measurement accuracy. The relevant equation for the induced EMF is:

[0081]

[0082] in, This is the induced electromotive force (induced voltage). For time, For parasitic inductance, The rate of change of current over time (current change rate) shows that the greater the rate of change of current over time, the greater the induced electromotive force, and the greater the impact on measurement accuracy. This is particularly significant in high-speed switching paths where the current changes rapidly.

[0083] In view of this, the present disclosure provides a shunt resistor, which utilizes the two cavities formed by the shunt resistor to cancel each other out the parasitic induced magnetic field generated in the space between the two cavities due to parasitic inductance, thereby reducing or even eliminating the induced electromotive force under the condition of rapid current change, thereby helping to weaken or even eliminate the influence of parasitic inductance on the measurement results in the metal strip scheme, and helping to improve the current measurement accuracy on the power path.

[0084] Figure 1A This is a first-view structural schematic diagram of a shunt resistor according to an illustrative embodiment. Figure 1BThis is a second-view structural schematic diagram of a first embodiment of a shunt resistor, shown according to an illustrative embodiment. Figure 1C This is a third-view structural schematic diagram of a first embodiment of a shunt resistor, shown according to an illustrative embodiment. (See attached diagram.) Figure 1A , Figure 1B and Figure 1C As shown, the shunt resistor mainly includes a first shunt bending piece 10, a second shunt bending piece 20, and a current-conducting piece 30. The first shunt bending piece 10 forms a first cavity 100 through a bending configuration. The second shunt bending piece 20 forms a second cavity 200 through a bending configuration. The current-conducting piece 30 connects the first shunt bending piece 10 and the second shunt bending piece 20. The first cavity 100 and the second cavity 200 have the same orientation, and the current flows sequentially through the first shunt bending piece 10, the current-conducting piece 30, and the second shunt bending piece 20.

[0085] In this embodiment, the bending configuration refers to a metal strip formed from a planar sheet material through stamping or bending processes to achieve a non-planar three-dimensional structure. The bending configuration can alter the current path, optimize spatial layout, and achieve specific electrical and / or mechanical properties. For example, in this embodiment, the bending configuration allows the parasitic induced magnetic field generated by the parasitic inductance of the shunt resistor to cancel each other out in the space between the first cavity 100 and the second cavity 200, thereby reducing or even eliminating the influence of parasitic inductance on the current measurement results and helping to improve the accuracy of current measurement.

[0086] To clearly define the locations and specific dimensions of the conductive and resistive parts in the shunt resistor, and to facilitate manufacturing processes, the first shunt bending piece 10 and the second shunt bending piece 20 are preferably designed with right-angle bends. This facilitates control over the square structural configuration and dimensions of the first cavity 100 and the second cavity 200, and makes it easier to achieve the purpose of canceling parasitic induced magnetic fields. See further details. Figure 1A , Figure 1B and Figure 1CAs shown in the schematic embodiment, the first shunt bending piece 10 includes a first conductive sheet portion 11, a second conductive sheet portion 12, a first resistive sheet portion 13, and a first power supply pin 14. The first resistive sheet portion 13 is connected to the first conductive sheet portion 11 at a first connecting edge 15, and the first resistive sheet portion 13 is connected to the second conductive sheet portion 12 at a second connecting edge 16. The extending directions of the first connecting edge 15 and the second connecting edge 16 are parallel to each other. A predetermined angle is formed between the first resistive sheet portion 13 and the first conductive sheet portion 11, and between the first resistive sheet portion 13 and the second conductive sheet portion 12. A first cavity 100 is formed by the first conductive sheet portion 11, the first resistive sheet portion 13, and the second conductive sheet portion 12 surrounding each other. The first power supply pin 14 is connected to the side of the first conductive sheet portion 11 away from the first connecting edge 15. The side of the second conductive sheet portion 12 away from the second connecting edge 16 is connected to the current guide piece 30.

[0087] In the illustrative embodiment, the first conductive sheet portion 11 and the second conductive sheet portion 12 are perpendicular to the first resistive sheet portion 13, that is, the preset angle between the first resistive sheet portion 13 and the first conductive sheet portion 11, and between the first resistive sheet portion 13 and the second conductive sheet portion 12 is 90°.

[0088] In the illustrative embodiment, the first resistive sheet portion 13 is a resistive portion, and the first conductive sheet portion 11 and the second conductive sheet portion 12 are conductive portions. In the illustrative embodiment, the resistive portion is made of either a manganese-copper alloy or a nickel-copper alloy; in the illustrative embodiment, the conductive portion is made of copper. In the illustrative embodiment, the first power pin 14 is integrally formed with the first conductive sheet portion 11, or it may be soldered to the first conductive sheet portion 11; the first power pin 14 is also a conductive portion. In the illustrative embodiment, the current-conducting plate 30 is integrally formed with the second conductive sheet portion 12, or it may be soldered to the second conductive sheet portion 12; the current-conducting plate 30 is also a conductive portion.

[0089] like Figure 1A , Figure 1B , Figure 1CAs shown in the illustrative embodiment, the shunt resistor of this disclosure further includes a first detection connection portion 41 and a second detection connection portion 42. The first detection connection portion 41 is connected to the first resistor body portion 13 at the first connection edge 15. The second detection connection portion 42 is connected to the first resistor body portion 13 at the second connection edge 16. The first detection connection part 41 and the second detection connection part 42 are used to connect to a current measuring device (circuit). The current measuring device (circuit) is directly connected to both ends of the first resistor sheet part 13 (resistor part) through the first detection connection part 41 and the second detection connection part 42. Alternatively, the first detection connection part 41 and the second detection connection part 42 can be directly connected to both ends of the first resistor sheet part 13 (resistor part) as part of the current measuring device (circuit). The current measuring device (circuit) is not connected to the power supply pins (first power supply pin 14 and second power supply pin 24 in the following description). This eliminates the influence of lead resistance (at least including the resistance of the first conductive sheet part 11 and the second conductive sheet part 12, and even including the resistance of the current guide piece 30 and the second shunt bending piece 20) and contact resistance (contact resistance at the first power supply pin 14 and the second power supply pin 24 in the following description) on the measurement accuracy in the power path, thereby achieving accurate detection of the voltage drop of the resistor body (first resistor sheet part 13).

[0090] like Figure 1A , Figure 1B , Figure 1C As shown, in the illustrative embodiment, the first detection connection portion 41 specifically includes a first detection connection plate portion 411 and a first detection pin 412. The first detection connection plate portion 411 is connected to the first resistor plate portion 13 at the first connection edge 15. The first detection pin 412 is connected to the side of the first detection connection plate portion 411 away from the first connection edge 15. In the illustrative embodiment, the second detection connection portion 42 specifically includes a second detection connection plate portion 421 and a second detection pin 422. The second detection connection plate portion 421 is connected to the first resistor plate portion 13 at the second connection edge 16. The second detection pin 422 is connected to the side of the second detection connection plate portion 421 away from the second connection edge 16. In the illustrative embodiment, the first detection pin 412 and the second detection pin 422 are used to connect a current measuring device (circuit).

[0091] like Figure 1A , Figure 1B , Figure 1CAs shown, in the illustrative embodiment, the first detection connecting piece 411 and the first conductive piece 11 are coplanar, and the second detection connecting piece 421 and the second conductive piece 12 are coplanar. This approach facilitates the manufacture of the shunt resistor of this embodiment using either an integrated molding method or a welding method. For example, when manufacturing the shunt resistor of this embodiment using an integrated molding method, it is convenient to achieve integrated stamping or bending of the first detection connecting piece 411 and the first conductive piece 11, as well as the second detection connecting piece 421 and the second conductive piece 12, through stamping or bending processes. When manufacturing the shunt resistor of this embodiment using a welding method, it is convenient to simultaneously align and weld the first detection connecting piece 411 and the first conductive piece 11 to the first connecting edge 15, and to simultaneously align and weld the second detection connecting piece 421 and the second conductive piece 12 to the second connecting edge 16.

[0092] See also Figure 1A , Figure 1B , Figure 1C As shown in the schematic embodiment, the second shunt bending piece 20 includes a third conductive sheet portion 21, a fourth conductive sheet portion 22, a second resistive sheet portion 23, and a second power supply pin 24. The second resistive sheet portion 23 is connected to the third conductive sheet portion 21 at a third connecting edge 25, and the second resistive sheet portion 23 is connected to the fourth conductive sheet portion 22 at a fourth connecting edge 26. The extending directions of the third connecting edge 25 and the fourth connecting edge 26 are parallel to each other. A predetermined angle is formed between the second resistive sheet portion 23 and the third conductive sheet portion 21, and between the second resistive sheet portion 23 and the fourth conductive sheet portion 22. The third conductive sheet portion 21, the second resistive sheet portion 23, and the fourth conductive sheet portion 22 surround each other to form a second cavity 200. The second power supply pin 24 is connected to the side of the fourth conductive sheet portion 22 away from the fourth connecting edge 26. The side of the third conductive sheet portion 21 away from the third connecting edge 25 is connected to the current guide piece 30.

[0093] In the illustrative embodiment, the third conductive sheet portion 21 and the fourth conductive sheet portion 22 are perpendicular to the second resistive sheet portion 23, that is, the preset angle between the second resistive sheet portion 23 and the third conductive sheet portion 21, and between the second resistive sheet portion 23 and the fourth conductive sheet portion 22 is 90°.

[0094] In the illustrative embodiment, the second resistive sheet portion 23 is a resistive portion, and the third conductive sheet portion 21 and the fourth conductive sheet portion 22 are conductive portions. In the illustrative embodiment, the resistive portion is made of either a manganese-copper alloy or a nickel-copper alloy, and the conductive portion is made of copper. In the illustrative embodiment, the second power pin 24 is integrally formed with the fourth conductive sheet portion 22; the second power pin 24 can also be soldered to the fourth conductive sheet portion 22, and the second power pin 24 is also a conductive portion. In the illustrative embodiment, the current-guiding piece 30 is integrally formed with the third conductive sheet portion 21; the current-guiding piece 30 can also be soldered to the third conductive sheet portion 21.

[0095] The shunt resistor in this embodiment needs to ensure that the parasitic induced magnetic field in the first cavity 100 can be weakened or even canceled by the parasitic induced magnetic field in the second cavity 200. Therefore, the distance between the first cavity 100 and the second cavity 200 should be kept as small as possible. The extension length of the current guide plate 30 (the length direction of the shunt resistor) determines the distance between the second conductive plate portion 12 and the third conductive plate portion 21, and also determines the distance between the first cavity 100 and the second cavity 200. Therefore, in the illustrative embodiment, the extension length of the current guide plate 30 (the length direction of the shunt resistor) ensures that the second conductive plate portion 12 and the third conductive plate portion 21 do not stick together, and the distance between the first cavity 100 and the second cavity 200 is kept as small as possible.

[0096] like Figure 1A , Figure 1B As shown in the schematic embodiment, the first cavity 100 and the second cavity 200 are of similar size, that is, the first cavity 100 and the second cavity 200 are the same or substantially the same size. In this way, in high-frequency switching power supply applications, when current flows through the shunt resistor, magnetic fields of similar intensity are formed in the first cavity 100 and the second cavity 200. Furthermore, the extension length of the current guide plate 30 (in the length direction of the shunt resistor) ensures that the distance between the first cavity 100 and the second cavity 200 is as small as possible, making the first cavity 100 and the second cavity 200 as adjacent as possible. This causes the parasitic induced magnetic field generated by the second shunt bending plate 20 and the parasitic induced magnetic field generated by the first shunt bending plate 10 to be opposite in direction in the first cavity 100, thus weakening or even canceling each other out. Therefore, when measuring the current passing through the first resistor body 13 through the first detection connection 41 and the second detection connection 42, the influence of parasitic inductance on the measurement results can be reduced or even eliminated due to the weakening or cancellation of the parasitic induced magnetic field in the first cavity 100.

[0097] like Figure 1A , Figure 1B , Figure 1CAs shown, in the illustrative embodiment, the guide plate 30 is located outside the first cavity 100 and the second cavity 200. Thus, two cavities arranged side-by-side in space are formed between the first cavity 100 and the second cavity 200, resulting in a relatively large size for the shunt resistor of this embodiment. Figure 1A , Figure 1B , Figure 1C As shown, because the first power supply pin 14 is connected to the first conductive plate portion 11 and the second power supply pin 24 is connected to the fourth conductive plate portion 22, and the first conductive plate portion 11 and the fourth conductive plate portion 22 are separated by the first resistor plate portion 13, the second conductive plate portion 12, the current guide plate 30, the third conductive plate portion 21 and the second resistor plate portion 23, the distance between the first power supply pin 14 and the second power supply pin 24 is relatively large. This shunt resistor is suitable for layouts with large power pad spacing on circuit boards.

[0098] Figure 2A This is a first-view structural schematic diagram of a second embodiment of a shunt resistor, shown according to an illustrative embodiment. Figure 2B This is a second-view structural schematic diagram of a second embodiment of a shunt resistor, shown according to an illustrative embodiment. Figure 2C This is a second-view structural schematic diagram of a second embodiment of a shunt resistor, shown according to an illustrative embodiment. (See diagram below.) Figure 2A , Figure 2B , Figure 2C As shown, the shunt resistor in the second embodiment mainly includes a first shunt bending piece 10, a second shunt bending piece 20, and a current-conducting piece 30. The first shunt bending piece 10 forms a first cavity 100 through a bending configuration. The second shunt bending piece 20 forms a second cavity 200 through a bending configuration. The current-conducting piece 30 connects the first shunt bending piece 10 and the second shunt bending piece 20. The first cavity 100 and the second cavity 200 have the same orientation, and current flows sequentially through the first shunt bending piece 10, the current-conducting piece 30, and the second shunt bending piece 20.

[0099] In the illustrative embodiment, the first shunt bending plate 10 and the second shunt bending plate 20 are in the form of right-angle bends, thereby facilitating control of the square structural configuration and size of the first cavity 100 and the second cavity 200, and easily achieving the purpose of counteracting parasitic induced magnetic fields. Specifically, see [link to previous section]. Figure 2A , Figure 2B , Figure 2CAs shown in the schematic embodiment, the first shunt bending piece 10 includes a first conductive sheet portion 11, a second conductive sheet portion 12, a first resistive sheet portion 13, and a first power supply pin 14. The first resistive sheet portion 13 is connected to the first conductive sheet portion 11 at a first connecting edge 15, and the first resistive sheet portion 13 is connected to the second conductive sheet portion 12 at a second connecting edge 16. The extending directions of the first connecting edge 15 and the second connecting edge 16 are parallel to each other. A predetermined angle is formed between the first resistive sheet portion 13 and the first conductive sheet portion 11, and between the first resistive sheet portion 13 and the second conductive sheet portion 12. A first cavity 100 is formed by the first conductive sheet portion 11, the first resistive sheet portion 13, and the second conductive sheet portion 12 surrounding each other. The first power supply pin 14 is connected to the side of the first conductive sheet portion 11 away from the first connecting edge 15. The side of the second conductive sheet portion 12 away from the second connecting edge 16 is connected to the current guide piece 30.

[0100] In the illustrative embodiment, the first conductive sheet portion 11 and the second conductive sheet portion 12 are perpendicular to the first resistive sheet portion 13, that is, the preset angle between the first resistive sheet portion 13 and the first conductive sheet portion 11, and between the first resistive sheet portion 13 and the second conductive sheet portion 12 is 90°.

[0101] In the illustrative embodiment, the first resistive sheet portion 13 is a resistive portion, and the first conductive sheet portion 11 and the second conductive sheet portion 12 are conductive portions. In the illustrative embodiment, the resistive portion is made of either a manganese-copper alloy or a nickel-copper alloy; in the illustrative embodiment, the conductive portion is made of copper. In the illustrative embodiment, the first power pin 14 is integrally formed with the first conductive sheet portion 11, or it may be soldered to the first conductive sheet portion 11; the first power pin 14 is also a conductive portion. In the illustrative embodiment, the current-conducting plate 30 is integrally formed with the second conductive sheet portion 12, or it may be soldered to the second conductive sheet portion 12; the current-conducting plate 30 is also a conductive portion.

[0102] like Figure 2A , Figure 2B , Figure 2CAs shown in the illustrative embodiment, the shunt resistor of the second embodiment further includes a first detection connection portion 41 and a second detection connection portion 42. The first detection connection portion 41 is connected to the first resistor body portion 13 at the first connection edge 15. The second detection connection portion 42 is connected to the first resistor body portion 13 at the second connection edge 16. The first detection connection portion 41 and the second detection connection portion 42 are used to connect to a current measuring device (circuit). The current measuring device (circuit) is directly connected to both ends of the first resistor body portion 13 (resistor portion) through the first detection connection portion 41 and the second detection connection portion 42. Alternatively, the first detection connection portion 41 and the second detection connection portion 42 can be directly connected to both ends of the first resistor body portion 13 (resistor portion) as part of the current measuring device (circuit). The current measuring device (circuit) is not connected to the power supply pin, which eliminates the influence of lead resistance and contact resistance in the power path on the measurement accuracy, and achieves accurate detection of the voltage drop of the resistor body (first resistor body portion 13).

[0103] like Figure 2B , Figure 2C As shown, in the illustrative embodiment, the first detection connection portion 41 specifically includes a first detection connection plate portion 411 and a first detection pin 412. The first detection connection plate portion 411 is connected to the first resistor plate portion 13 at the first connection edge 15. The first detection pin 412 is connected to the side of the first detection connection plate portion 411 away from the first connection edge 15. Figure 2A , Figure 2C As shown, in the illustrative embodiment, the second detection connection portion 42 specifically includes a second detection connection plate portion 421 and a second detection pin 422. The second detection connection plate portion 421 is connected to the first resistor plate portion 13 at the second connection edge 16. The second detection pin 422 is connected to the side of the second detection connection plate portion 421 away from the second connection edge 16. In the illustrative embodiment, the first detection pin 412 and the second detection pin 422 are used to connect a current measuring device (circuit).

[0104] like Figure 2A , Figure 2B , Figure 2CAs shown, in the illustrative embodiment, the first detection connecting piece 411 and the first conductive piece 11 are coplanar, and the second detection connecting piece 421 and the second conductive piece 12 are coplanar. This approach facilitates the manufacture of the shunt resistor of this embodiment using either an integrated molding method or a welding method. For example, when manufacturing the shunt resistor of this embodiment using an integrated molding method, it is convenient to achieve integrated stamping or bending of the first detection connecting piece 411 and the first conductive piece 11, as well as the second detection connecting piece 421 and the second conductive piece 12, through stamping or bending processes. When manufacturing the shunt resistor of this embodiment using a welding method, it is convenient to simultaneously align and weld the first detection connecting piece 411 and the first conductive piece 11 to the first connecting edge 15, and to simultaneously align and weld the second detection connecting piece 421 and the second conductive piece 12 to the second connecting edge 16.

[0105] See also Figure 2A , Figure 2B , Figure 2C As shown in the schematic embodiment, the second shunt bending piece 20 includes a third conductive sheet portion 21, a fourth conductive sheet portion 22, a second resistive sheet portion 23, and a second power supply pin 24. The second resistive sheet portion 23 is connected to the third conductive sheet portion 21 at a third connecting edge 25, and the second resistive sheet portion 23 is connected to the fourth conductive sheet portion 22 at a fourth connecting edge 26. The extending directions of the third connecting edge 25 and the fourth connecting edge 26 are parallel to each other. A predetermined angle is formed between the second resistive sheet portion 23 and the third conductive sheet portion 21, and between the second resistive sheet portion 23 and the fourth conductive sheet portion 22. The third conductive sheet portion 21, the second resistive sheet portion 23, and the fourth conductive sheet portion 22 surround each other to form a second cavity 200. The second power supply pin 24 is connected to the side of the fourth conductive sheet portion 22 away from the fourth connecting edge 26. The side of the third conductive sheet portion 21 away from the third connecting edge 25 is connected to the current guide piece 30.

[0106] In the illustrative embodiment, the third conductive sheet portion 21 and the fourth conductive sheet portion 22 are perpendicular to the second resistive sheet portion 23, that is, the preset angle between the second resistive sheet portion 23 and the third conductive sheet portion 21, and between the second resistive sheet portion 23 and the fourth conductive sheet portion 22 is 90°.

[0107] In the illustrative embodiment, the second resistive sheet portion 23 is a resistive portion, and the third conductive sheet portion 21 and the fourth conductive sheet portion 22 are conductive portions. In the illustrative embodiment, the resistive portion is made of either a manganese-copper alloy or a nickel-copper alloy, and the conductive portion is made of copper. In the illustrative embodiment, the second power pin 24 is integrally formed with the fourth conductive sheet portion 22; the second power pin 24 can also be soldered to the fourth conductive sheet portion 22, and the second power pin 24 is also a conductive portion. In the illustrative embodiment, the current-guiding piece 30 is integrally formed with the third conductive sheet portion 21; the current-guiding piece 30 can also be soldered to the third conductive sheet portion 21.

[0108] like Figure 2A , Figure 2B , Figure 2C As shown, in the second embodiment, the guide vane 30 is located inside the first cavity 100 and outside the second cavity 200, and the second diversion bend vane 20 is located in the first cavity 100 (wherein, the first cavity 100 includes the structure of the second diversion bend vane 20 and the guide vane 30). Thus, a nested structure is formed between the first cavity 100 and the second cavity 200, with the second cavity 200 nested within the first cavity 100. Figure 1A , Figure 1B , Figure 1C In contrast to the first embodiment shown, the size of the shunt resistor in the second embodiment can be made relatively small, while... Figure 2A , Figure 2B , Figure 2C As shown, because the first power pin 14 is connected to the first conductive sheet portion 11 and the second power pin 24 is connected to the fourth conductive sheet portion 22, and because the second cavity 200 (second shunt bending piece 20) is nested within the first cavity 100, the positions of the first conductive sheet portion 11 and the fourth conductive sheet portion 22 are adjacent. Therefore, the distance between the first power pin 14 and the second power pin 24 is small. This type of shunt resistor is suitable for layouts with small power pad spacing on circuit boards.

[0109] Meanwhile, the nested structure of the second cavity 200 in the second embodiment nested within the first cavity 100 allows the parasitic induced magnetic field in the first cavity 100 to be more effectively weakened or even canceled by the parasitic induced magnetic field in the second cavity 200. Thus, when the current passing through the first resistive sheet portion 13 is measured through the first detection connection portion 41 and the second detection connection portion 42, the influence of parasitic inductance on the measurement results can be reduced or even eliminated due to the weakening or cancellation of the parasitic induced magnetic field in the first cavity 100.

[0110] The shunt resistor of this disclosure embodiment is a single unit, wherein the relative positions between the various components are fixed. Therefore, in the illustrative embodiment, the first shunt bending piece 10, the second shunt bending piece 20, and the current-conducting piece 30 are integrally formed, meaning the entire shunt resistor can be integrally formed. Alternatively, welding technology can be used to fix the various parts together. For example, in the illustrative embodiment, the first shunt bending piece 10 and the current-conducting piece 30 are welded together, as are the current-conducting piece 30 and the second shunt bending piece 20. Alternatively, in the illustrative embodiment, the current-conducting piece 30 is integrally formed with either the first shunt bending piece 10 or the second shunt bending piece 20, and is welded to the other of the first shunt bending piece 10 and the second shunt bending piece 20. For example, the current-conducting piece 30 is integrally formed with the first shunt bending piece 10 and welded to the second shunt bending piece 20, or the current-conducting piece 30 is integrally formed with the second shunt bending piece 20 and welded to the first shunt bending piece 10. In addition, the various parts of the first diversion bending piece 10 and / or the various parts of the second diversion bending piece 20 can be connected by either integral molding or welding.

[0111] Figure 3 This is a schematic diagram of the principle structure of the shunt resistor according to an embodiment of this disclosure, as shown below. Figure 3 and combined Figure 1A , Figure 1B , Figure 1C , Figure 2A , Figure 2B and Figure 2C As shown, the box represents the first shunt bending piece 10. The lower left and right sides are power pins (equivalent to the first power pin 14 and the second power pin 24), and the upper left and right sides are detection pins (equivalent to the first detection pin 412 and the second detection pin 422). Inside the first shunt bending piece 10, as shown in the box, there are parasitic induced magnetic fields in two directions. The outward direction indicates the direction of the magnetic flux of the parasitic induced magnetic field generated by the first shunt bending piece 10 within the first cavity 100, while the inward direction indicates the direction of the magnetic flux of the mutual inductance parasitic induced magnetic field within the first cavity 100. The mutual inductance parasitic induced magnetic field is the parasitic induced magnetic field generated by the second shunt bending piece 20.

[0112] According to Faraday's law of electromagnetic induction, the total magnetic flux passing through the inside of the coil circuit... When a change occurs, a voltage will be induced in the coil circuit. ,Right now:

[0113]

[0114] For a uniform magnetic flux distribution:

[0115]

[0116] in, Magnetic flux density Let be the perpendicular cross-sectional area through which the magnetic flux passes. Therefore, we have:

[0117]

[0118] The parasitic inductance of the shunt resistor contained in the differential voltage measurement signal at the input of the current sensing amplifier in a current measuring device (circuit) will generate a non-negligible induced voltage during rapid switching (when the current reverses rapidly).

[0119] Figure 4 This is a schematic diagram illustrating the relationship between induced voltage and parasitic inductance at a current change rate of 2000 A / µs, according to an illustrative embodiment. Figure 4 As shown, at the rate of change of current (i.e. When the parasitic inductance is 2000A / µs, the induced voltage increases significantly with the increase of parasitic inductance. For example, when the parasitic inductance is 1nH, the induced voltage is about 2V, while when the parasitic inductance rises to 5nH, the induced voltage rises to about 10V.

[0120] Figure 5 This is a schematic diagram of the magnetic flux distribution of the shunt resistor in the first embodiment. (Combined with...) Figure 5 and Figure 1A As shown, the magnetic field state of the first cavity 100 (the first shunt bending piece 10, which is equivalent to a coil) is analyzed to visually observe the induced voltage generated by the change in the magnetic field within the first cavity 100 using a magnetic path model:

[0121]

[0122] in, This represents the total induced voltage in the first cavity 100. The inductance is generated by the current of the first cavity 100 itself. Let be the rate of change of current in the first cavity 100. The coupling inductance (mutual inductance) between the second cavity 200 (the second shunt bending piece 20, which is equivalent to another coil) and the first cavity 100. The current change rate of the second cavity 200. This indicates the number of turns of the coil represented by the first cavity 100. This refers to the self-magnetic flux of the first cavity 100 (i.e., the magnetic flux generated by the current in the first cavity 100 and passing through the first cavity 100 itself). This represents the mutual magnetic flux between the second cavity 200 and the first cavity 100 (i.e., the magnetic flux generated by the current in the second cavity 200 and passing through the first cavity 100). This represents the mutual magnetic flux between the first cavity 100 and the second cavity 200 (i.e., the magnetic flux generated by the current in the first cavity 100 and passing through the second cavity 200).

[0123] Combining the above formula and Figure 5 It can be seen that if the changing current of the second cavity 200 Generate magnetic flux through the first cavity 100 The closer to the second cavity 200, the better the current conversion. The magnetic flux generated by self-induction The smaller the electromagnetic induction effect of parasitic inductance, the higher the measurement accuracy.

[0124] It is evident that in the first embodiment, the electromagnetic induction effect caused by the parasitic inductance of the first cavity 100 by the second cavity 200 weakens or even eliminates it, which helps to reduce the parasitic inductance of the shunt resistor and thus helps to improve the current measurement accuracy on the power path.

[0125] Figure 6 This is a schematic diagram of the magnetic flux distribution of the shunt resistor in the second embodiment. Wherein, It is the self-magnetic flux of the first cavity 100, and It is the self-magnetic flux of the second cavity 200. and The directions are opposite, and because the second cavity 200 is nested within the first cavity 100, and the size of the second cavity 200 is only slightly smaller than the size of the first cavity 100, therefore, Able to Therefore, in the second embodiment, the electromagnetic induction effect caused by the parasitic inductance of the first cavity 100 by the second cavity 200 is weakened or even eliminated, which helps to reduce the parasitic inductance of the shunt resistor and thus helps to improve the current measurement accuracy on the power path.

[0126] Figure 7 This is a circuit diagram illustrating the current measurement using a shunt resistor according to an embodiment of this disclosure. Figure 7As shown, when using the shunt resistor of this embodiment for current measurement, it conforms to a four-wire Kelvin connection. The four-wire Kelvin connection physically separates the current path (power path) from the voltage detection path (for current detection). Independent current terminals (such as the first power pin 14 and the second power pin 24) carry the load current, and independent detection terminals (such as the first detection connection part 41 and the second detection connection part 42) are directly connected to the resistive element (such as the first resistive sheet part 13) to measure the pure resistance voltage drop, thereby reducing or even avoiding measurement errors introduced by the power path. Figure 7 In the diagram, the direction of current flow is indicated by an arrow with an "i" symbol, and ESL stands for Equivalent Series Inductance.

[0127] Combination Figure 7 Using circuit diagrams and Ohm's law, ideal voltage, resistance, and current relationships can be obtained:

[0128]

[0129] in, It is the voltage at the positive terminal of the current sensor. It detects the voltage at the negative terminal of the current sensor. It is the resistance value of the shunt resistor (i.e., the first resistor plate 13). This is the measured current. The formula for ideal current can be obtained from the above equation:

[0130]

[0131] Combination Figure 7 By combining the circuit schematic with Ohm's law, we can also derive the formula for actual current:

[0132]

[0133] in, This is the actual current. The equivalent series resistance includes, except for Other than contact resistance, lead resistance, etc.

[0134] The purpose of the four-wire Kelvin connection method is to reduce... To improve detection accuracy.

[0135] Using the above formulas for ideal current and actual current, we can obtain the formula for the relative error of current detection:

[0136]

[0137] Figure 8 This is a schematic diagram illustrating the relative error curve relationship of current detection according to an illustrative embodiment. For example... Figure 8As shown, the horizontal axis is The vertical axis represents the current measurement error, i.e. It can be seen that The introduced current measurement error is proportional to the ratio of the equivalent series resistance to the shunt resistance.

[0138] Figure 9 This is a schematic diagram comparing the resistivity-temperature characteristics of manganese copper and copper according to an illustrative embodiment, where the horizontal axis represents temperature and the vertical axis represents the resistance-temperature drift rate. In this embodiment, the resistivity-temperature characteristics of materials such as manganese copper and nickel copper are very stable, reaching 100-200 ppm / ℃ (parts per million per degree Celsius), for example... Figure 9 As shown, compared to the dramatic changes in the resistivity-temperature characteristic curve of copper, the resistivity-temperature characteristic of manganese copper is very stable, thus making it fully suitable for measurements over a wide temperature range in power scenarios.

[0139] The shunt resistor of this embodiment utilizes a first shunt bending piece 10 and a second shunt bending piece 20 to form a first cavity 100 and a second cavity 200. During current flow, parasitic induced magnetic fields are generated in the first cavity 100 and the second cavity 200 respectively. When the magnetic flux of the parasitic induced magnetic field generated in the first cavity 100 passes through the second cavity 200, it cancels the parasitic induced magnetic field generated in the second cavity 200. Similarly, when the magnetic flux of the parasitic induced magnetic field generated in the second cavity 200 passes through the first cavity 100, it cancels the parasitic induced magnetic field generated in the first cavity 100. This achieves mutual cancellation of the parasitic induced magnetic field generated by parasitic inductance between the first cavity 100 and the second cavity 200, thereby helping to reduce or even eliminate the induced electromotive force under conditions of rapid current changes. The shunt resistor of this embodiment, in the metal strip scheme, helps to weaken or even eliminate the influence of parasitic inductance on the measurement results, and helps to improve the current measurement accuracy on the power path.

[0140] In the shunt resistor of this embodiment, the relative positional relationship between the first cavity and the second cavity might lead one to believe that parasitic capacitance is generated inside the shunt resistor. However, it should be noted that the parasitic capacitance generated in the shunt resistor of this embodiment is very small and can be ignored because the shunt resistor of this embodiment is a whole, and the corresponding parallel parts of the first cavity and the second cavity are (e.g.) Figure 1A Between the second conductive sheet portion 12 and the third conductive sheet portion 21 shown, Figure 2AThere is almost no potential difference between the first conductive sheet portion 11 and the fourth conductive sheet portion 22, between the first resistive sheet portion 13 and the second resistive sheet portion 23, and between the second conductive sheet portion 12 and the third conductive sheet portion 21. In the frequency range of 100KHz to 1MHz of the switching power supply, the potential difference can be basically ignored. Therefore, the benefits brought by the shunt resistor of this embodiment in eliminating parasitic inductance far outweigh the impact of the parasitic capacitance that may exist.

[0141] In an illustrative embodiment, an electronic device is also provided, which includes a shunt resistor as described in any of the preceding embodiments. In this illustrative embodiment, the electronic device may be an electronic device requiring current detection and power monitoring, such as various devices based on the PCIe (Peripheral Component Interconnect Express) standard, OAM (OCP Accelerator Module) boards, and other computing device boards; computing devices may include AI (Artificial Intelligence) servers; and the electronic device may also be other types of servers.

[0142] The above description is merely a preferred embodiment of this disclosure and is not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A shunt resistor, characterized in that, include: The first diversion bending piece forms a first cavity through a bending configuration; The second diversion bending piece forms a second cavity through a bending configuration; A flow guide plate, wherein the flow guide plate is connected between the first flow diversion bend plate and the second flow diversion bend plate; The first cavity and the second cavity are oriented in the same direction, and the current flows sequentially through the first shunt bending plate, the guide plate and the second shunt bending plate.

2. The shunt resistor according to claim 1, characterized in that, The first diversion bending piece includes: First conductive sheet body; Second conductive sheet portion; The first resistive sheet portion is connected to the first conductive sheet portion at a first connecting edge, and the first resistive sheet portion is connected to the second conductive sheet portion at a second connecting edge. The extending directions of the first connecting edge and the second connecting edge are parallel to each other. Furthermore, a predetermined angle is formed between the first resistive sheet portion and the first conductive sheet portion, and between the first resistive sheet portion and the second conductive sheet portion. The first cavity is formed by the first conductive sheet portion, the first resistive sheet portion, and the second conductive sheet portion. The first power supply pin is connected to the side of the first conductive sheet portion away from the first connection edge; The side of the second conductive sheet body that is away from the second connecting edge is connected to the flow guide sheet.

3. The shunt resistor according to claim 2, characterized in that: The first conductive sheet portion and the second conductive sheet portion are perpendicular to the first resistive sheet portion.

4. The shunt resistor according to claim 2, characterized in that, The shunt resistor also includes: The first detection connection part is connected to the first resistor sheet body part at the first connection edge; The second detection connection part is connected to the first resistor sheet body part at the second connection edge.

5. The shunt resistor according to claim 4, characterized in that: The first detection connection part includes: The first detection connection piece is connected to the first resistor piece at the first connection edge; The first detection pin is connected to the side of the first detection connection piece that is away from the first connection edge; The second detection connection includes: The second detection connection piece is connected to the first resistor piece at the second connection edge; The second detection pin is connected to the side of the second detection connection plate that is away from the second connection edge.

6. The shunt resistor according to claim 1, characterized in that, The second diversion bending piece includes: Third conductive sheet body; Fourth conductive sheet body; The second resistive sheet portion is connected to the third conductive sheet portion at a third connecting edge, and the second resistive sheet portion is connected to the fourth conductive sheet portion at a fourth connecting edge. The extending directions of the third connecting edge and the fourth connecting edge are parallel to each other. Furthermore, a predetermined angle is formed between the second resistive sheet portion and the third conductive sheet portion, and between the second resistive sheet portion and the fourth conductive sheet portion. The second cavity is formed by the third conductive sheet portion, the second resistive sheet portion, and the fourth conductive sheet portion. The second power supply pin is connected to the side of the fourth conductive sheet portion away from the fourth connection edge; The side of the third conductive sheet body that is away from the third connecting edge is connected to the flow guide sheet.

7. The shunt resistor according to claim 6, characterized in that: The third conductive sheet portion and the fourth conductive sheet portion are perpendicular to the second resistive sheet portion.

8. The shunt resistor according to claim 6, characterized in that: The second resistive sheet portion is a resistive portion, and the third conductive sheet portion and the fourth conductive sheet portion are conductive portions.

9. The shunt resistor according to claim 1, characterized in that: The guide vane is located on the outside of the first cavity and the second cavity.

10. The shunt resistor according to claim 1, characterized in that: The flow guide plate is located inside the first cavity and outside the second cavity, while the second flow diversion deflector is located in the first cavity.

11. The shunt resistor according to claim 1, characterized in that: The first diversion bending plate, the second diversion bending plate, and the guide plate are integrally formed; or... The first diversion bending plate and the guide plate, as well as the guide plate and the second diversion bending plate, are welded together. Alternatively, the flow guide plate is integrally formed with either the first flow diversion bending plate or the second flow diversion bending plate, and is welded to the other of the first flow diversion bending plate and the second flow diversion bending plate.

12. An electronic device, characterized in that, Includes the shunt resistor as described in any one of claims 1 to 11.

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