Differential Hall current sensor and manufacturing method thereof

Abstract

The embodiment of the invention provides a differential Hall current sensor and a manufacturing method thereof, and belongs to the technical field of semiconductors. The differential Hall current sensor comprises a current bar; the insulating layer is bonded on the upper surface of the current bar; the at least two Hall elements are symmetrically arranged on the two sides of the upper surface of the insulating layer in the current direction; and the at least one deflection magnetism gathering block is attached to the magnetic induction surfaces of the at least two Hall elements and is used for deflecting a magnetic field component of the current magnetic field in the direction parallel to the magnetic induction surfaces of the Hall elements into a magnetic field component in the direction perpendicular to the magnetic induction surfaces of the Hall elements. According to the differential Hall current sensor, the current magnetic field is gathered through the deflection magnetism gathering block to form a conduction magnetic circuit, the directions of the magnetic field components are changed, the Hall element obtains the magnetic field intensity formed by superposing the magnetic field components in the two directions, and the measurement sensitivity is improved.

Description

Technical Field

[0001] The present invention belongs to the field of semiconductor technology, and in particular relates to a differential Hall current sensor and a manufacturing method thereof. Background Art

[0002] At present, Hall sensors with integrated Hall elements or Hall chips are widely used for efficient measurement of electrical signals. With the technological updates in the fields of new energy, energy storage, battery management, etc., higher requirements are put forward for the measurement sensitivity and measurement range of Hall sensors.

[0003] Since the Hall sensor can only detect magnetic fields perpendicular to its magnetic sensing surface, in order to utilize the perpendicular magnetic field generated by the current, the existing Hall sensor uses two Hall sensors placed on both sides of the current row. In order to enhance the signal, the width of the current row needs to be narrowed to concentrate the current. This solution will cause the current row to heat up in the narrowed part due to the current concentration, affecting the reliability of the device. It will also limit the measurement range of the Hall sensor and affect its anti-interference ability due to the large distance between the two Hall sensors.

[0004] Another solution is to use a larger C-shaped magnetic core to concentrate the magnetic field around the Hall element to enhance the magnetic field. This solution will result in a larger overall size of the measuring device, and will also cause magnetic saturation or hysteresis problems during measurement, thereby reducing the device's measurement accuracy and reliability. If the C-shaped magnetic core is not used, the current row will be designed to be more compact in order to concentrate the current and increase the magnetic field, which will lead to the problem of more concentrated current and increased heat generation.

[0005] In view of this, it is necessary to optimize the design of a new Hall current sensor to completely or partially solve the defects of the above current sensor. Summary of the invention

[0006] In order to solve at least one aspect of the above problems and defects in the prior art, the embodiment of the present invention provides a differential Hall current sensor and a manufacturing method thereof, which forms a conductive magnetic circuit by deflecting a magnetic concentrator to gather the current magnetic field and change the direction of the magnetic field component, so that the Hall obtains the magnetic field strength of the superposition of the magnetic field components in two directions, thereby improving the measurement sensitivity. The technical solution is as follows:

[0007] According to one aspect of the present invention, a differential Hall current sensor is provided, the differential Hall current sensor comprising:

[0008] Current bus;

[0009] an insulating layer bonded to an upper surface of the current bus;

[0010] At least two Halls are symmetrically arranged on both sides of the upper surface of the insulating layer along the current direction;

[0011] At least one deflection magnetic focusing block is arranged close to the magnetic sensing surfaces of at least two Halls, and at least one deflection magnetic focusing block is used to deflect the magnetic field component of the current magnetic field in the direction parallel to the magnetic sensing surface into the magnetic field component in the direction perpendicular to the magnetic sensing surface.

[0012] Specifically, the current bus has a U-shaped structure with equal width in each section, and both ends of the U-shaped structure are connected in series with the external current bus to be measured; the insulating layer is arranged on the upper surface of the bent section of the U-shaped structure or on the upper surface of any straight section of the U-shaped structure.

[0013] In some embodiments, the insulating layer, at least two Halls and at least one deflection magnetic focusing block constitute a differential Hall current sensor subunit; and at least one differential Hall current sensor subunit is arranged at intervals on the upper surface of the current row.

[0014] In some embodiments, an IC circuit board is also arranged on or in the insulating layer, and at least two Hall sensors output measurement signals after being differentiated by the IC circuit board; or the IC circuit board is separately arranged on the outside of the current bus, and at least two Hall sensors are electrically connected to the IC circuit board through metal wires and output measurement signals after being differentiated by the IC circuit board.

[0015] In some embodiments, the at least two Halls include at least one pair of Halls symmetrically arranged on both sides of the upper surface of the insulating layer about the center of the current row, and one pair of Halls in the at least one pair of Halls includes a first Hall and a second Hall arranged oppositely.

[0016] Specifically, in a pair of Halls, a first gap is provided between a first Hall and a second Hall, and the first gap is set to a predetermined distance or equal to zero.

[0017] In some embodiments, for a pair of Halls, at least one deflection magnetic focusing block includes a first deflection magnetic focusing block centrally symmetrically arranged above the pair of Halls, and the first deflection magnetic focusing block is respectively attached to the upper magnetic sensing surface of the pair of Halls and is located in the central area of ​​the Hall of the pair of Halls.

[0018] In some embodiments, for a pair of Halls, the first deflection magnetic focusing block is divided into a first part and a second part, and the first part and the second part are respectively symmetrically attached to the upper magnetic sensing surfaces of the first Hall and the second Hall and are respectively located in the center area of ​​the first Hall and the second Hall.

[0019] Specifically, in some embodiments, one end of the first portion away from the center of the current row is aligned with the edge of the current row on the same side; and one end of the second portion away from the center of the current row is aligned with the edge of the current row on the same side.

[0020] Specifically, in some embodiments, there is a second gap between the first portion and the second portion.

[0021] In some embodiments, for a pair of Halls, at least one deflection magnetic focusing block also includes a second deflection magnetic focusing block centrally and symmetrically arranged below the pair of Halls, and the second deflection magnetic focusing blocks are respectively attached to the lower magnetic sensing surfaces of the pair of Halls.

[0022] Specifically, the first part and the second part of the first deflection magnetic focusing block are arranged on two sides close to a pair of Halls, and the second deflection magnetic focusing block is located in the middle area of ​​the pair of Halls.

[0023] Specifically, the first part of the first deflection magnetic focusing block, the second part of the first deflection magnetic focusing block and the second deflection magnetic focusing block are arranged symmetrically about the center of the current row and their plane projections coincide with the Hall center area of ​​the differential Hall current sensor.

[0024] In some embodiments, when any one of the at least one pair of Hall sensors is an integrated Hall element, the pins of the integrated Hall element are directly soldered to the Hall element circuit of the IC circuit board and then connected to the signal processing circuit provided on the IC circuit board.

[0025] In some embodiments, when any pair of at least one pair of Hall sensors is a Hall bare chip, the Hall bare chip is directly placed on the insulating layer and connected to the Hall chip circuit of the IC circuit board through metal wires, and then connected to the signal processing circuit set on the IC circuit board.

[0026] In some embodiments, when at least one pair of Halls are Hall bare chips and the first gap between the two Hall bare chips of each pair is equal to zero, a common ground electrode is set at the position where the two Hall bare chips contact each other, and the common ground electrode and the working electrodes of the two Hall bare chips respectively provide the working voltage of the Hall bare chips together, and the Hall electrodes of the two Hall bare chips provide a differential Hall voltage.

[0027] In some embodiments, the cross-sectional shape of at least one deflection magnetic focusing block is a centrally symmetrical shape, and the centrally symmetrical shape is any one of a diamond, a square, a rectangle, a circle, an ellipse, or any combination thereof.

[0028] In some embodiments, at least one deflection magnetic focusing block is provided with a contact structure at a position close to the magnetic sensing surface of the Hall, and the cross-sectional shape of the contact structure is any one of circular, elliptical, and triangular shapes or any combination thereof.

[0029] In some embodiments, the material of at least one deflection magnetic focusing block is a high magnetic permeability material that is non-magnetic itself, and the high magnetic permeability material is any one of ferrite, soft magnet, and nano-magnetic crystal.

[0030] In some embodiments, the material of each Hall in the at least two Hall electrodes is a Hall material, and the Hall material is any one of GaAs, InSb, and InAs.

[0031] In some embodiments, at least one deflection magnetic focusing block is prepared by photolithography and sputtering and then fixedly connected by bonding.

[0032] In some embodiments, the current row, the insulating layer, at least two Halls and at least one deflection magnetic focusing block are packaged together through a packaging structure.

[0033] According to another aspect of the present invention, a method for manufacturing a differential Hall current sensor is provided, for manufacturing the differential Hall current sensor described according to the above aspect, the manufacturing method comprising:

[0034] Manufacturing current bars;

[0035] manufacturing an insulating layer bonded to an upper surface of the current bus;

[0036] At least two Hall electrodes are symmetrically arranged on both sides of the upper surface of the insulating layer along the current direction;

[0037] Manufacturing at least one deflection magnetic focusing block, the at least one deflection magnetic focusing block is arranged close to the magnetic sensing surfaces of at least two Halls, and the at least one deflection magnetic focusing block is used to deflect the magnetic field component of the current magnetic field in the direction parallel to the magnetic sensing surface into the magnetic field component in the direction perpendicular to the magnetic sensing surface;

[0038] The coefficient of the current flowing through the current row of each pair of Halls in at least two Halls and the Hall voltage is obtained by calibration measurement.

[0039] The differential Hall current sensor and the manufacturing method thereof provided by the embodiments of the present invention have at least one or part of the following advantages:

[0040] (1) The differential Hall current sensor and the manufacturing method thereof provided in the embodiments of the present invention gather the magnetic field generated by the current row to be measured by deflecting the magnetic concentrator to form a conductive magnetic circuit, thereby increasing the magnetic flux density;

[0041] (2) After the differential Hall current sensor and its manufacturing method provided by the embodiment of the present invention forms a conductive magnetic circuit by deflecting the magnetic concentrator, the direction of the magnetic field component parallel to the magnetic sensing surface of the Hall generated by the current row to be measured can be deflected to the same direction as the magnetic field component originally perpendicular to the magnetic sensing surface of the Hall, so that the Hall can obtain magnetic field components in two directions at the same time, thereby increasing the magnetic flux density of the magnetic field that can be sensed, thereby improving its measurement sensitivity;

[0042] (3) The differential Hall current sensor and its manufacturing method provided in the embodiment of the present invention further gathers the magnetic field generated by the current row to be measured by adding multiple deflection magnetic focusing blocks to a pair of Halls, thereby enhancing the magnetic field strength and improving the measurement sensitivity;

[0043] (4) The differential Hall current sensor and the manufacturing method thereof provided in the embodiments of the present invention package the current row to be measured together into the differential Hall current sensor, and fully utilize the current magnetic field by deflecting the magnetic focusing block. At the same time, there is no need to significantly narrow the width of the current row, thereby avoiding the heat caused by the narrowing of the current row, improving the reliability and environmental tolerance of the device, and helping to expand the measurement range to measure a current with a higher intensity;

[0044] (5) The differential Hall current sensor and the manufacturing method thereof provided in the embodiments of the present invention can flexibly set the number of deflection magnetic focusing blocks attached to the magnetic sensing surfaces of the paired Halls, the layout positions of the multiple deflection magnetic focusing blocks, and the cross-sectional shape of each deflection magnetic focusing block, and can use mature processing technology to manufacture the deflection magnetic focusing blocks, with a simple process and no additional manufacturing cost.

[0045] (6) The differential Hall current sensor and the manufacturing method thereof provided in the embodiments of the present invention arrange the Hall above the current row, and the spacing between the paired Halls can be reduced to zero, which can reduce the package size and greatly improve the anti-interference ability of the Hall.

[0046] (7) The differential Hall current sensor and the manufacturing method thereof provided in the embodiments of the present invention can arrange a differential Hall current sensor subunit at any position above the current row without affecting its signal gain and sensing performance, have a higher installation tolerance, and improve the flexibility of the installation layout;

[0047] (8) The differential Hall current sensor and the manufacturing method thereof provided in the embodiments of the present invention can appropriately arrange a certain number of differential Hall current sensor sub-units above the current bus, and improve the installation tolerance by balancing the signal gain between the differential Hall current sensor sub-units. There is no need to recalibrate the differential Hall current sensor during installation, thereby reducing the calibration workload;

[0048] (9) The differential Hall current sensor and the manufacturing method thereof provided in the embodiments of the present invention can further improve the measurement sensitivity of the differential Hall current sensor by properly arranging a plurality of differential Hall current sensor sub-units above the current bus. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] These and / or other aspects and advantages of the present invention will become apparent and readily understood from the following description of the preferred embodiments in conjunction with the accompanying drawings, in which:

[0050] Figure 1ais a schematic top view of a packaging structure of a differential Hall current sensor according to Embodiment 1 of the present invention;

[0051] Figure 1b for Figure 1a A cross-sectional schematic diagram of the packaging structure of the differential Hall current sensor shown;

[0052] Figure 2 for Figure 1a and Figure 1b A schematic diagram of magnetic lines of force of a conducting magnetic circuit and magnetic field components on the Hall surface formed by the differential Hall current sensor of Example 1 under a current magnetic field B is shown;

[0053] Figure 3a-3d A schematic diagram of different cross-sectional shapes of a deflection magnetic focusing block of a differential Hall current sensor according to an embodiment of the present invention;

[0054] Figure 4 A schematic diagram of an electrode layout of a pair of Hall electrodes of a differential Hall current sensor according to an embodiment of the present invention;

[0055] Figure 5 A schematic diagram of another electrode layout of a pair of Hall electrodes of a differential Hall current sensor according to an embodiment of the present invention;

[0056] Figure 6a is a schematic top view of a packaging structure of a differential Hall current sensor according to Embodiment 2 of the present invention;

[0057] Figure 6b for Figure 6a A cross-sectional schematic diagram of the packaging structure of the differential Hall current sensor shown;

[0058] Figure 7 is a schematic cross-sectional view of a packaging structure of a differential Hall current sensor according to Embodiment 3 of the present invention;

[0059] Figure 8 is a schematic cross-sectional view of a packaging structure of a differential Hall current sensor according to Embodiment 4 of the present invention;

[0060] Fig. 9 is a schematic cross-sectional view of a packaging structure of a differential Hall current sensor according to Embodiment 5 of the present invention;

[0061] Fig.10a A schematic top view of a packaging structure of a differential Hall current sensor according to Embodiment 6 of the present invention;

[0062] Fig.10b A schematic top view of another packaging structure of a differential Hall current sensor according to Embodiment 6 of the present invention;

[0063] Fig.11 is a schematic top view of a packaging structure of a differential Hall current sensor according to Embodiment 7 of the present invention;

[0064] Fig.12 for Fig.11 The signal gain balance curve diagram of the differential Hall current sensor shown;

[0065] Fig.13 Schematic top view of the packaging structure of the differential Hall current sensor according to Embodiment 8 of the present invention. DETAILED DESCRIPTION

[0066] The technical solution of the present invention is further specifically described below by examples and in conjunction with the accompanying drawings. In the specification, the same or similar reference numerals indicate the same or similar components. The following description of the embodiments of the present invention with reference to the accompanying drawings is intended to explain the overall inventive concept of the present invention and should not be construed as a limitation of the present invention.

[0067] It should also be understood that, although the terms "first", "second", "third", etc. may be used in the following embodiments of the present invention to describe that a component includes two or more components, these components should not be limited to these terms, which are only used to distinguish each component from each other. And the descriptions of "upper", "lower", etc. indicating directions are only for illustrative purposes to illustrate the relative positions of components or the relative directions of, for example, current, magnetic field, magnetic field components, etc., and should not be understood as a limitation of the present invention.

[0068] Nowadays, with the development of technology in the fields of advanced electronic systems, new energy, energy storage, etc., Hall current sensors based on the Hall effect are widely used in current detection of various electronic devices and measurement of non-electrical physical quantities such as torque, displacement, acceleration, speed, etc. Therefore, higher requirements are put forward for the performance parameters of Hall sensors such as measurement sensitivity, anti-interference ability and measurable range.

[0069] Based on the above requirements, in order to further enhance the perceptible magnetic field strength of the Hall sensor, improve its measurement sensitivity, reduce the impact of signal interference on the Hall, and expand the current measurement range, according to one aspect of the present invention, a new differential Hall current sensor 100 is provided. Figure 1a and Figure 1b , shows the structure of the differential Hall current sensor 100, which mainly includes the following five parts:

[0070] Current row 10;

[0071] an insulating layer 20 bonded to the upper surface of the current bank 10;

[0072] At least two Halls 30 are symmetrically arranged on both sides of the upper surface of the insulating layer 20 along the current direction;

[0073] At least one deflection magnetic focusing block 40 is disposed close to the magnetic sensing surfaces of at least two Halls 30, and the at least one deflection magnetic focusing block 40 is used to deflect the magnetic field component of the current magnetic field in the direction parallel to the magnetic sensing surface of the Hall into the magnetic field component in the direction perpendicular to the magnetic sensing surface;

[0074] The packaging structure 50 packages the current row 10, the insulating layer 20, at least two Hall elements 30 and at least one deflection magnetic focusing block 40 together.

[0075] In one example, preferably, Figure 1a The top view of the differential Hall current sensor 100 is shown, wherein the current bar 10 shown has a U-shaped structure with equal widths in each section, and the two ends of the U-shaped structure are connected in series with the external current bar to be measured by, for example, metal pins, metal positioning holes, etc. Since at least two Halls 30 are first integrated on the insulating layer 20 and then placed on the current bar 10, the width of the current bar 10 does not need to be narrowed, and current accumulation and heat accumulation will not occur.

[0076] In one example, alternatively, the current row 10 may also have a U-shaped structure with different widths in each section. For example, if you want to further increase the current magnetic field density and improve the Hall sensing sensitivity, you can slightly narrow the width of the current row 10 at the location where the insulating layer 20 carrying at least two Halls 30 and at least one deflection magnet block 40 is installed. However, the range of this narrowing is very small, and it is not the obvious scale of the current row in the prior art, so it can still achieve the beneficial effects of increasing the perceptible magnetic field strength, improving the sensitivity, and reducing the heat generation of the current row.

[0077] In one example, the insulating layer 20 is disposed on the upper surface of the bent section of the U-shaped structure of the current bus 10 (eg, Figure 1a The position shown) or set on the upper surface of any straight section of the U-shaped structure.

[0078] In one example, the insulating layer 20, at least two Halls 30 and at least one deflection magnetic focusing block 40 form a differential Hall current sensor subunit; then, at least one of the differential Hall current sensor subunits is disposed at intervals on the upper surface of the U-shaped current row 10.

[0079] That is, those skilled in the art can design and arrange one, two or more differential Hall current sensor subunits according to the actual measurement scenario, and arrange the differential Hall current sensor subunits at different positions of the U-shaped structure of the current bank 10. The following is further described by some embodiments, and the structures and layouts of the differential Hall current sensor subunits provided in each embodiment are only some illustrative examples, and those skilled in the art should not be understood as a limitation of the present invention.

[0080] In one example, an IC circuit board is further provided on the insulating layer 20 or in the insulating layer 20. The IC circuit board is used to power the at least two Halls 30 on the one hand, and on the other hand, the at least two Halls 30 output measurement signals after differential processing by the IC circuit board. Alternatively, the IC circuit board can also be separately provided on the outside of the current bus 10, in which case the at least two Halls 30 are electrically connected to the IC circuit board through metal wires and output measurement signals after differential processing by the IC circuit board.

[0081] In one example, at least two Hall sensors 30 include at least one pair of Hall sensors 30 arranged symmetrically on both sides of the upper surface of the insulating layer 20 about the center of the current bus 10. Alternatively, one, two or more pairs of Hall sensors may be arranged on one differential Hall current sensor subunit (each pair of Hall sensors is arranged in parallel, and a certain distance is maintained between each adjacent pair of Hall sensors). Alternatively, one, two or more differential Hall current sensor subunits may also be arranged on the current bus 10.

[0082] In one example, at least two Halls 30 may use an integrated Hall element or a Hall bare chip. Alternatively, each Hall element in at least two Halls 30 is made of a Hall material. Theoretically, any material that can produce a Hall effect (i.e., a Hall material) can be used to manufacture the Hall in the present invention and its embodiments. Preferably, the Hall material is made of a III-V semiconductor material such as GaAs, InSb, InAs, or other types of semiconductor materials.

[0083] In one example, considering that at least one deflection magnetic focusing block 40 needs to first focus the magnetic field and then deflect and adjust the direction of the magnetic field component on the Hall, the material of the at least one deflection magnetic focusing block 40 is a high magnetic permeability material that is not magnetic. Alternatively, the magnetic conductive material is any one of ferrite, soft magnet, and nano-magnetic crystal.

[0084] The selection of high magnetic permeability materials and Hall materials can be achieved using existing technical means. Those skilled in the art can select suitable Hall materials to make Hall 30 according to the actual measurement scenario, and select suitable high magnetic permeability materials to make deflection focusing block 40. This example only provides some illustrative examples, and those skilled in the art should not understand it as a limitation of the present invention.

[0085] Based on the basic structure of the differential Hall current sensor 100, considering that various measurement scenarios may occur in actual use, it is necessary to adjust the layout, selection, electrical connection, etc. of the internal components of the differential Hall current sensor 100 according to the requirements of the measurement scenario. The specific structure of the differential Hall current sensor 100 and the layout of various internal components are described in detail below through 8 embodiments.

[0086] Example 1

[0087] Combination Figure 1a , Figure 1b and Figure 2 , shows the structure of the differential Hall current sensor 100 of Example 1, the shape and direction of the magnetic lines of force of the conductive magnetic circuit under the current magnetic field B, and the direction of each magnetic field component on the magnetic sensing surface of the Hall. The differential Hall current sensor 100 mainly includes four parts, namely, a current row 10, an insulating layer 20, two Halls forming a pair (a first Hall 31 and a second Hall 32, and the Hall in this Example 1 is described by taking two Hall bare chips as an example) and a deflection magnetic focusing block (i.e., a first deflection magnetic focusing block 41). The specific settings of the four parts are described as follows.

[0088] The current bank 10 has the following features: Figure 1a The U-shaped structure shown. The preferred U-shaped structure of embodiment 1 is a U-shaped structure of equal width. Alternatively, it can also be designed as a U-shaped structure of unequal width to adjust the width of the current row 10 to be equal to the width of the insulating layer 20 or to match within a certain accuracy range.

[0089] The insulating layer 20 is bonded to the upper surface of the current bus 10. Preferably, the insulating layer 20 is disposed on the upper surface of the bent section of the U-shaped structure of the current bus 10. Of course, alternatively, the insulating layer 20 may also be bonded to other positions on the upper surface of the current bus 10, such as any positions on the two straight sections of the U-shaped structure.

[0090] Specifically, in one example, the insulating layer 20 can be made of insulating materials such as high molecular polymers, resins, fibers, ceramics, etc. For the selection of insulating materials, those skilled in the art can select suitable insulating materials according to the actual measurement scenario. This example only provides some illustrative examples, and those skilled in the art should not be understood as a limitation of the present invention.

[0091] Furthermore, in one example, for the differential Hall current sensor 100 using a Hall bare chip, an IC circuit board can be alternatively provided on the insulating layer 20 or in the insulating layer 20. The first Hall 31 and the second Hall 32 are first electrically connected to the IC circuit board through metal wires, silver glue, etc., and on the one hand, they obtain power from the IC circuit board, and on the other hand, they output measurement signals after differential processing by the IC circuit board. Alternatively, the IC circuit board can also be separately provided on the outside of the current bus 10, and the connection mode and signal transmission mode of the first Hall 31 and the second Hall 32 with the IC circuit board remain unchanged.

[0092] The number of at least two Hall electrodes 30 is set to 2 and constitutes a pair of Hall electrodes, which includes a first Hall electrode 31 and a second Hall electrode 32 , and is centrally symmetrically arranged on both sides of the upper surface of the insulating layer 20 along the current direction of the current row 10 .

[0093] Specifically, in one example, preferably, the first Hall 31 and the second Hall 32 using Hall bare chips are placed directly on the insulating layer 20, and connected to the Hall chip circuit of the IC circuit board embedded in the insulating layer 20 through metal wires, and then connected to the signal processing circuit set on the IC circuit board.

[0094] Furthermore, in one example, there is a first gap between the first Hall 31 and the second Hall 32. Alternatively, the first gap can be set to a predetermined distance, and the specific value of the predetermined distance can be designed according to the actual measurement scenario. In general, when the paired Halls gradually get closer, the anti-interference ability of the two gradually increases. Since the interference signal is not evenly distributed, when the spacing between the paired Halls is large, the intensity difference of the interference signal at the two Hall positions is also large; when the spacing between the paired Halls is gradually close (for example, the spacing between the two can be shortened to within 100μm), the intensity of the interference signal at the two Hall positions is almost equal, then, when the differential processing is performed later, the differential elimination can be made more thorough, thereby improving the sensing sensitivity of the Hall.

[0095] Alternatively, in one example, the first gap between the first Hall 31 and the second Hall 32 may also be equal to zero, which can further reduce the size of the final package structure, so that the differential Hall current sensor 100 can be further miniaturized. In particular, when the first Hall 31 and the second Hall 32 use integrated Hall elements, since the volume of the Hall element increases after packaging, placing the two completely close together can avoid increasing the package size of the differential Hall current sensor 100.

[0096] The number of at least one deflection magnetic focusing block 40 is set to 1, namely, the first deflection magnetic focusing block 41. The first deflection magnetic focusing block 41 is centrally symmetrically arranged above the first Hall 31 and the second Hall 32, respectively abutting against the upper magnetic sensing surfaces of the first Hall 31 and the second Hall 32, and located in the center area of ​​the Hall of the first Hall 31 and the second Hall 32.

[0097] Specifically, in one example, the cross-sectional shape of the first deflection magnetic focusing block 41 is a centrally symmetrical shape. For example, the X-axis, Y-axis and origin are set on a plane. Then, when the cross-sectional center of the first deflection magnetic focusing block 41 is located at the origin, the cross-sectional shape is symmetrical about both the X-axis and the Y-axis. Preferably, the centrally symmetrical shape is any one of a rhombus, a square, a rectangle, a circle, and an ellipse, or any combination thereof. The first deflection magnetic focusing block 41 is also provided with a contact structure at a position close to the magnetic sensing surfaces of the first Hall 31 and the second Hall 32. The cross-sectional shape of the contact structure is any one of a circle, an ellipse, and a triangle, or a combination thereof.

[0098] Specifically, in one example, see Figure 3a-3d , four cross-sectional structures of the first deflection magnetizing block 41 are shown as illustrative examples. Figure 3a-3d As shown, the central body part 4101 of the first deflection focusing magnetic block 41 is preferably rectangular or square in cross-section, and alternatively, a cross-section close to or approximately rectangular or square can be selected. Contact structures 4102 are symmetrically arranged at two ends of the central body part 4101 that are symmetrical about the center. The contact structure 4102 can be, for example Figure 3a The triangular cross-sectional shape of the part, especially the protruding corner part thereof, may also be, for example Figure 3b The cross-sectional shape of a triangle and a circle, especially the circular contact part, can also be, for example Figure 3d The elliptical cross-sectional shape, especially the parts at both ends of the elliptical major axis. This example only provides some illustrative examples, and those skilled in the art should not be understood as a limitation of the present invention.

[0099] In one example, at least one deflection magnetic focusing block 40 (here, the first deflection magnetic focusing block 41) has a preset thickness. Alternatively, each of the at least one deflection magnetic focusing block 40 may have a different preset thickness, but each deflection magnetic focusing block should maintain a uniform thickness, and the preset thickness range is 100-1000 μm, and the specific value of the preset thickness can be set according to actual measurement requirements.

[0100] In one example, alternatively, at least one deflection magnetic focusing block 40 (here, the first deflection magnetic focusing block 41) is prepared by photolithography and sputtering and then fixedly connected by bonding. The advantage of making the deflection magnetic focusing block on the Hall by photolithography and sputtering is that its cross-sectional shape can be symmetrical and the position can be accurately attached. Alternatively, the high magnetic permeability material can be pre-made into an appropriate cross-sectional shape by methods such as precision deposition and then fixedly installed on the Hall by bonding.

[0101] The above-mentioned insulating layer 20, first Hall 31, second Hall 32 and first deflection magnetic focusing block 41 are combined into a differential Hall current sensor sub-unit arranged on the upper surface of the bending section of the U-shaped structure of the current bus 10, and packaged together with the current bus 10 through the packaging structure 50.

[0102] Through the above arrangement, when the differential Hall current sensor 100 of the first embodiment is connected in series with the current bus to be measured through the current bus 10, first refer to Figure 1a , assuming that the current direction is to enter from the right end of the U-shaped structure of the current row 10, pass through the differential Hall current sensor subunit, and then flow out from the left end of the U-shaped structure. At this time, the current generates a magnetic field B, and the magnetic field B generates magnetic field components in two directions perpendicular to the current direction (of course, it can also be in the opposite direction, that is, entering from the left end of the U-shaped structure and flowing out from its right end, then the direction of the magnetic field B is also reversed). Combined with Figure 2 The two magnetic field components perpendicular to the current direction are B1 and B2. The magnetic field component B1 is perpendicular to the magnetic sensing surfaces of the two Halls and is defined as the perpendicular magnetic field component B1; the magnetic field component B2 is parallel to the magnetic sensing surfaces of the two Halls and is defined as the parallel magnetic field component B2. The first deflection magnetic focusing block 41 forms a magnetic field around the two Halls. Figure 2 The closed conductive magnetic circuit shown in the figure (closed solid line) gathers the magnetic field generated by the current to increase the magnetic flux passing through the two Halls. At the same time, the direction of the parallel magnetic field component B2 can be adjusted through the conductive magnetic circuit to turn it to the direction of the vertical magnetic field component B1. In this way, within the conductive magnetic circuit, the two Halls can sense both the vertical magnetic field component B1 and the parallel magnetic field component B2 with deflected direction, achieving the effect of simultaneously sensing the superimposed two-dimensional magnetic field components.

[0103] Specifically, by symmetrically arranging the symmetrical cross-sections of the first deflection magnetic focusing block 41 on the magnetic sensing surfaces of the paired Halls, the parallel magnetic field component B2 can be deflected into a magnetic field component perpendicular to the magnetic sensing surface and consistent with the direction of the original vertical magnetic field component B1. After the deflection, the magnetic field components in the original two dimensional directions can be superimposed to form a magnetic field perceptible to the Hall. On the one hand, the perceptible magnetic field intensity of the Hall is improved, and the magnetic flux is increased, thereby significantly improving the sensing sensitivity of the differential Hall current sensor 100; on the other hand, the signal gain of the Hall is improved, which is helpful for the subsequent differential signal processing for paired Halls. In various embodiments of the present invention, compared with traditional differential Hall sensors, the magnetic field detection sensitivity can be increased by more than 1.5 times.

[0104] In one example, see Figure 4 , showing the layout of the first Hall 31 and the second Hall 32 and the first deflection magnetic focusing block 41a of Example 1. Alternatively, the first deflection magnetic focusing block 41a uses an overall rhombus-shaped cross-sectional shape, which is symmetrical about the central axis, and the two symmetrical sharp corners thereof are symmetrically attached to the upper magnetic sensing surfaces of the first Hall 31 and the second Hall 32, respectively. Since the pair of Halls uses a Hall bare chip, in order to prevent its electrodes from short-circuiting, preferably, the first gap between the first Hall 31 and the second Hall 32 is set to a predetermined distance, and the specific value of the predetermined distance can be designed according to the actual measurement scenario.

[0105] In one example, alternatively, the electrodes of the two Hall bare chips forming a pair of the first Hall 31 and the second Hall 32 may be optimized so that the first gap between the two is equal to zero, that is, the two Hall bare chips are connected side by side by merging the electrodes.

[0106] Specifically, see Figure 5 A common ground electrode including a signal common ground electrode 311 and a working common ground electrode 312 is arranged at the position where the first Hall 31a and the second Hall 32a are in contact. The common ground electrode and the working electrodes 313 and 323 of the two Halls in a pair provide the Hall working voltage together, and the Hall electrodes 314 and 324 of the two Halls provide the differential Hall voltage. With such an electrode design, the differential signal can be directly obtained from the voltage between the two Hall electrodes.

[0107] Example 2

[0108] See also Figure 6a and Figure 6b , shows the structure of the differential Hall current sensor 101 of Example 2. Compared with Example 1, the basic structural composition is the same, and the specific settings of each part are not repeated. The following only describes the settings that are different from Example 1.

[0109] In the differential Hall current sensor 101 of the second embodiment, an integrated Hall element is used to replace the Hall bare chip in the first embodiment. That is, the first Hall 31b and the second Hall 32b disposed between the first deflection magnetic focusing block 41b and the insulating layer 20 both use integrated Hall elements.

[0110] In one example, the two integrated Hall elements are no longer affected by the electrodes, and alternatively, they are closely arranged together, that is, the first gap between the two Halls is equal to zero. Alternatively, the IC circuit board 21 is arranged in the insulating layer 20, that is, the insulating layer 20 is composed of the actual insulating layer 22 and the IC circuit board 21 located thereunder. The pins of each integrated Hall element are directly soldered to the Hall element circuit of the IC circuit board 21 and then connected to the signal processing circuit arranged on the IC circuit board 21 for signal processing and signal output.

[0111] Those skilled in the art can combine and adjust the solutions in Example 1 and Example 2 according to the actual measurement scenario and measurement requirements. For example, the specific numerical setting of the first gap between the two Halls in a pair in Example 1, the first deflection magnetic focusing block with a cross-sectional shape set on the upper magnetic sensing surface of the two Halls, and other technical solutions can be used in Example 2 alone or in combination. The above examples are only some illustrative examples, and those skilled in the art should not be understood as a limitation of the present invention.

[0112] Example 3

[0113] Taking into account that in some current measurement scenarios, such as strong current measurement, since the current value of the current to be measured is large and the magnetic field strength increases accordingly, the use of the deflection magnetic block 40 can be appropriately reduced. This can save materials for manufacturing the deflection magnetic block 40 while ensuring the measurement performance of the differential Hall current sensor, thereby further reducing manufacturing costs.

[0114] See also Figure 7 , shows the structure of the differential Hall current sensor 102 of Example 3. Compared with Example 1 and / or Example 2, the basic structural composition is the same, the difference is that the first deflection magnetic block 41 is divided into two parts (a first part 411 and a second part 412), and the total volume of the first deflection magnetic block 41 is reduced to a certain extent.

[0115] Specifically, in one example, the first deflection magnetic focusing block 41 is divided based on Example 1. For a pair of Halls (i.e., the first Hall 31 and the second Hall 32), the first deflection magnetic focusing block 41 is divided into a first part 411 and a second part 412. After the division, the first part 411 and the second part 412 are respectively symmetrically attached to the upper magnetic sensing surfaces of the first Hall 31 and the second Hall 32, and are respectively arranged on both sides close to the first Hall 31 and the second Hall 32. At this time, Figure 7 As shown, there is a second gap between the first part 411 and the second part 412 of the first deflection magnetic focusing block 41. Alternatively, the second gap is similar to the aforementioned first gap and can be set according to the actual current detection situation. Of course, the first part 411 and the second part 412 need to be attached to the Hall center area of ​​their corresponding Hall.

[0116] Preferably, in one example, Figure 7 As shown, one end of the first part 411 of the first deflection magnetic focusing block 41 away from the center of the current row 10 is aligned with the edge of the current row 10 on the same side (the rightmost side in the figure). At the same time, one end of the second part 412 of the first deflection magnetic focusing block 41 away from the center of the current row 10 is aligned with the edge of the current row 10 on the same side (the leftmost side in the figure).

[0117] After the first deflection magnetic focusing block 41 is divided, the current magnetic field around the first Hall 31 and the second Hall 32 can still be formed as follows: Figure 7 The closed magnetic conducting circuit shown (closed solid line).

[0118] Alternatively, in one example, for other structural settings of Embodiment 3, reference may be made to the settings in Embodiment 1 and Embodiment 2. Figure 7 As shown, preferably, the first Hall 31 and the second Hall 32 are arranged to be aligned with the outer edge of the insulating layer 20 away from the center of the current row 10, and at the same time, the first part 411 and the second part 412 of the first deflection magnetic focusing block 41 respectively arranged on the upper magnetic sensing surface of the pair of Halls are also aligned with the outer edge of the insulating layer 20. For example, the adjustment of the first spacing between the paired Halls, the adjustment of the second spacing between the separated first part 411 and the second part 412, the thickness or width of the first part 411 and the second part 412, etc. For another example, the cross-sectional shape of the first deflection magnetic focusing block 41 can also be set with reference to the various schemes or combinations of the various schemes given in Example 1, etc. The above examples only provide some illustrative examples, and those skilled in the art should not be understood as a limitation of the present invention.

[0119] Example 4

[0120] On the basis of Embodiments 1-3, when the sensing sensitivity of the differential Hall current sensor needs to be further improved, multiple deflection magnetic focusing blocks and paired Halls can be arranged by adding deflection magnetic focusing blocks.

[0121] See also Figure 8 , shows the structure of the differential Hall current sensor 103 of Example 4. For a pair of Halls (in order to distinguish from other embodiments, the pair of Halls in Example 4 includes a first Hall 31c and a second Hall 32c), at least one deflection magnetic focusing block 40 also includes a second deflection magnetic focusing block 42 centrally and symmetrically arranged below the pair of Halls, and the second deflection magnetic focusing blocks 42 are respectively attached to the lower magnetic sensing surfaces of the pair of Halls. Alternatively, the first deflection magnetic focusing block 41 at this time can use the setting scheme of being divided into two parts in Example 3 (here, in order to distinguish from other embodiments, the first deflection magnetic focusing block 41 is divided into a first part 411a and a second part 412a in Example 4).

[0122] Specifically, the first part 411a and the second part 412a of the first deflection magnetic focusing block 41 are arranged on both sides close to the pair of Halls (the first Hall 31c and the second Hall 32c), and the second deflection magnetic focusing block 42 is located in the middle area of ​​the pair of Halls. The first part 411a of the first deflection magnetic focusing block 41, the second part 412a of the first deflection magnetic focusing block 41 and the second deflection magnetic focusing block 42 are arranged to be symmetrical about the center of the current row 10 and their plane projections coincide with the Hall center area of ​​the differential Hall current sensor. The Hall center area refers to the center range area of ​​the upper and lower magnetic sensing surfaces of the Hall.

[0123] In one example, the specific configuration of the first part 411a and the second part 412a of the first deflection magnetic focusing block 41 may refer to Example 3 and will not be described in detail here.

[0124] In one example, the second deflection focusing block 42 may be as follows: Figure 8 The width shown is not completely equal to the width of the insulating layer 20. In this case, an insulating layer or an insulating buffer layer can be filled at both ends of the outer side; the width of the second deflection magnetic focusing block 42 can also be set to be consistent with the width of the insulating layer 20. This example only provides some illustrative examples, and those skilled in the art should not be understood as a limitation of the present invention.

[0125] Example 5

[0126] Similar to the arrangement of the multiple deflection magnetic focusing blocks in Example 4, in Example 5, the arrangement of the upper and lower layers of different deflection magnetic focusing blocks can be swapped to form a Fig. 9 The structure of the differential Hall current sensor 104 is shown.

[0127] Specifically, in one example, for a pair of Halls (in order to distinguish from other embodiments, a pair of Halls in Embodiment 5 includes a first Hall 31d and a second Hall 32d), a total of three deflection magnetic blocks 40 are arranged, which is opposite to the layout of Embodiment 4. The second deflection magnetic block 42a is arranged above the pair of Halls, and the first part 411b and the second part 412b of the first deflection magnetic block 41 are arranged respectively below the pair of Halls.

[0128] Alternatively, in one example, the configuration of the three deflection magnetic focusing blocks in Example 5 may refer to the configurations in Examples 1 to 4 or any combination thereof, and will not be repeated here.

[0129] Example 6

[0130] In the above embodiments 1-5, a differential Hall current sensor subunit composed of an insulating layer 20, a pair of Halls 30 and at least one deflection magnet block 40 is preferably arranged on the upper surface of the bent section of the U-shaped structure of the current row 10. Considering the actual measurement scenario, see Fig.10a and Fig.10b , showing that the above-mentioned one differential Hall current sensor subunit (the figure exemplarily shows the use of the differential Hall current sensor 100 of embodiment 1 as the differential Hall current sensor subunit, of course, other embodiments 2-5 can also be selected) is arranged at other positions of the U-shaped structure of the current row 10, while ensuring that the center line of a pair of Halls 30 must be perpendicular to the direction of the current to be measured, that is, the pair of Halls 30 need to always remain symmetrical with the center of the current row 10. For example Fig.10a The structure of the differential Hall current sensor 105 shown in the figure arranges the differential Hall current sensor subunit on the straight section of the U-shaped structure on the left side of the figure and tilts clockwise at a certain angle to ensure that a pair of Hall current sensors thereon are symmetrical about the current center of the current row 10. Fig.10b The structure of the differential Hall current sensor 106 shown in the figure arranges the differential Hall current sensor subunit on the straight section of the U-shaped structure on the right side of the figure and tilts counterclockwise at a certain angle to ensure that a pair of Halls thereon are symmetrical about the current center of the current row 10. After testing, the change in the above arrangement position has a negligible effect on the performance indicators of the differential Hall current sensor (such as magnetic field detection sensitivity, signal gain, etc.), so the installation tolerance error of the differential Hall current sensor subunit at which position of the U-shaped structure current row 10 is arranged can be increased. Those skilled in the art can select different arrangement positions according to actual measurement needs.

[0131] Example 7

[0132] In order to further enhance the sensing signal of the differential Hall current sensor and thus improve its magnetic field detection sensitivity, while increasing the installation tolerance, based on Examples 1-5, see Fig.11 , shows the structure of the differential Hall current sensor 107 of Example 7, where two identical differential Hall current sensor sub-units are arranged on the current bus 10.

[0133] In one example, in order to improve the installation tolerance, two differential Hall current sensor subunits with the same structure are selected and symmetrically arranged on the upper surface of the two straight sections of the U-shaped structure of the current bus 10 and packaged. In this way, not only can twice the sensing signal be obtained to double the magnetic field sensing sensitivity, but also the error that may be caused by the installation can be eliminated by combining the two sets of sensing signals.

[0134] Specifically, taking the use of two identical differential Hall current sensor subunits of Embodiment 4 as an example (here defined as subunit A and subunit B), alternatively, the differential Hall current sensors of other embodiments 1, 2, 3 and 5 may also be used as differential Hall current sensor subunits. When subunit A and subunit B are arranged on a current bank 10 at the same time, it is necessary to ensure that the structures of the two subunits are consistent, but the specific structure of the differential Hall current sensor subunit to be used can be set by using the above embodiments and possible combinations thereof according to actual measurement requirements.

[0135] Further, see Fig.12 , shows the signal gain balance curve of the differential Hall current sensor 107 of Example 7. When the spacing between subunit A and subunit B on the current row 10 is set as Fig.12 When the positions are shown in the diagram, it can be seen that the corresponding signal gains of the two have reached a, and the total signal gain has reached 2a. Therefore, when installing the differential Hall current sensor subunits, as long as the spacing between the above two groups remains unchanged, no matter whether the installation position of subunit A or subunit B deviates to the left or right from the design position, the gain of one will increase and the gain of the other will decrease, but the total gain of the two can be maintained at the level of 2a, thus effectively offsetting the installation error. Fig.12 As shown in the figure, for example, if subunit A is offset to the right, then when subunit B is installed, the distance between the two is kept unchanged and subunit B is also offset to the right, that is, the position where the corresponding vertical dotted line in the figure re-intersects the gain curve. It can be seen that the signal gain of subunit A is improved after the offset, but at the same time, the signal gain of subunit B is reduced and the reduction is equal to the increase of subunit A. In other words, the total gain of the two is still 2a after the offset.

[0136] Example 8

[0137] In combination with the above-mentioned embodiment 6 and embodiment 7, the number of differential Hall current sensor sub-units is further increased to 3, see Fig.13 , shows the structure of the differential Hall current sensor 108 of Example 8, where subunit A1, subunit B1 and subunit C are arranged on the current bar 10, wherein the layout positions of subunit A1 and subunit B1 are the same as those of Example 7, and subunit C is arranged on the bending section of the U-shaped structure of the current bar 10 (refer to the layout position of Example 1). When subunit A1, subunit B1 and subunit C are arranged on a current bar 10 at the same time, it is necessary to ensure that the structures of the three subunits are consistent, but the specific structure of the differential Hall current sensor subunit to be used can be set according to the actual measurement requirements using the above embodiments and possible combinations thereof.

[0138] Such an arrangement can make the sensing signals of the three differential Hall current sensor sub-units superimpose and obtain three times the magnetic field detection sensitivity. Similar to Example 7, it can also have a larger installation tolerance. Alternatively, for the case of multiple sub-units, the IC circuit board can be separately set to correspond to a sub-unit, or it can be combined to set an integral IC circuit board. The specific electrical connection method refers to the aforementioned embodiments and will not be repeated here.

[0139] As for the installation tolerance, the tolerance of the traditional differential Hall current sensor needs to be on the order of 10 microns. When the structure and internal layout of the differential Hall current sensor of Examples 6-8 are adopted, the installation tolerance can be increased to the order of hundreds of microns. After the installation tolerance is increased, the differential Hall current sensor only needs to be calibrated and measured at the factory, and no calibration is required during installation and use.

[0140] In one example, after the differential Hall current sensor based on the above embodiments is manufactured, the interference between the paired Hall current sensors can be eliminated by signal differentiation, ensuring that the Hall current sensor has a high and stable sensing sensitivity. The principle of Hall current differential signal is briefly described as follows.

[0141] A pair of Hall electrodes are provided in the differential Hall current sensor 100 of the first embodiment, that is, Figure 1a , Figure 1b and Figure 2 The first Hall 31 and the second Hall 32 are shown as examples. Figure 2Theoretically, when the current to be measured is detected, under the action of the magnetic field B, two magnetic field components in two directions are generated on the magnetic sensing surfaces of the two Hall sensors. One is the vertical magnetic field component B1 perpendicular to the magnetic sensing surface of the Hall sensor, which is also the magnetic field component that the Hall sensor can sense; the other is the parallel magnetic field component B2 perpendicular to the direction of the current to be measured but parallel to the magnetic sensing surface of the Hall sensor, which is the magnetic field component that cannot be sensed by the Hall sensor.

[0142] Since the two Halls are arranged symmetrically relative to the current row 10 in the direction of the current, for each Hall, the vertical magnetic field component B1 is equal in magnitude but opposite in direction; at the same time, the height of each Hall relative to the current row 10 is consistent. At this time, on each Hall, the proportional relationship between the vertical magnetic field component B1 and the parallel magnetic field component B2 is also fixed.

[0143] At this time, let B2 = k1*B1, k1 is the magnetic field proportionality coefficient, for the U-shaped current bus 10, the measured current I0 can be obtained 2 ∝B1 2 +B2 2 , that is, I0∝B1.

[0144] The vertical magnetic field components B1 acting on the first Hall 31 and the second Hall 32 are of the same magnitude but opposite in direction, and the output voltages of the two in the horizontal direction are:

[0145] V 水平-1 = -V 水平-2 = a*B1; where V 水平-1 represents the horizontal voltage generated by the vertical magnetic field component B1 on the first Hall 31, V 水平-2 represents the horizontal voltage generated by the vertical magnetic field component B1 on the second Hall 32, a is a first proportional constant, and the value of a is related to the inherent parameters of the Hall itself (such as the Hall structure size, the material used to make the Hall, etc.).

[0146] The parallel magnetic field components B2 acting on the first Hall 31 and the second Hall 32 are of the same magnitude and direction, and the output voltages of the two in the vertical direction are:

[0147] V 垂直-1 = -V 垂直-2 = b*B2; where V 垂直-1 V represents the vertical voltage generated by the parallel magnetic field component B2 on the first Hall 31. 垂直-2 It represents the vertical voltage generated by the parallel magnetic field component B2 on the second Hall 32. b is the second proportional constant, which is similar to the first proportional constant a. The value of b is related to the inherent parameters of the Hall itself (such as the Hall structure size, the material used to make the Hall, etc.).

[0148] When the interference magnetic field signal C is added, the total output voltages of the first Hall 31 and the second Hall 32 are respectively:

[0149] The total output voltage of the first Hall 31, V1 = a*B1 + b*B2 + C;

[0150] The total output voltage of the second Hall 32, V2 = -a*B1 - b*B2 + C;

[0151] Further calculate the differential signal between V1 and V2 , the calculation formula is as follows: .

[0152] It can be seen that the difference eliminates the interference. At the same time, it is known that B2 = k1*B1, then we can get:

[0153] Differential signaling , can be set , where K is the coefficient of the current flowing through the current block and the Hall voltage, which needs to be determined by calibrating the Hall measurement; the first proportional constant a, the second proportional constant b, and the magnetic field proportional coefficient k1 are all Hall's inherent variables, which are determined by its factory configuration. In other words, as long as the differential signal is obtained By calibrating the coefficient K between the current passing through the current bus and the Hall voltage, the current value I0 of the current to be measured input into the current bus 10 can be calculated.

[0154] In one example, since the deflection magnetic block 40 used in the actual differential Hall current sensor may have an installation position error during its installation, it is easy to cause the vertical magnetic field component B1 or the horizontal magnetic field component B2 to have a deviation in the signal gain coefficient of each Hall. In order to correct this deviation, it is usually necessary to adjust the differential signal The calibration is performed, and the specific calibration steps are as follows (taking the pair of Hall electrodes provided in the differential Hall current sensor 100 of the above embodiment 1 as an example):

[0155] At this time, the vertical magnetic field components B1 acting on the first Hall 31 and the second Hall 32 are the same in magnitude but opposite in direction. Considering the installation position error of the first deflection magnetic focusing block 41 (including the second deflection magnetic focusing block 42 in other embodiments), the output voltages of the two in the horizontal direction are respectively:

[0156] V 水平-1 = a1*B1;

[0157] V 水平-2 = -a2*B2;

[0158] Among them, V水平-1 represents the horizontal voltage generated by the vertical magnetic field component B1 on the first Hall 31, V 水平-2 It represents the horizontal voltage generated by the vertical magnetic field component B1 on the second Hall 32. a1 and a2 are the first proportional constants corresponding to the first Hall 31 and the second Hall 32 respectively after adding the installation position error. When the differential Hall current sensor 100 is assembled, the value of the above-mentioned first proportional constant is also determined.

[0159] Similarly, when the parallel magnetic field component B2 acts on the first Hall 31 and the second Hall 32 respectively, the output voltages of the two in the horizontal direction are respectively:

[0160] V 垂直-1 = b1*B2;

[0161] V 垂直-2 = -b2*B2;

[0162] Among them, V 垂直-1 V represents the vertical voltage generated by the parallel magnetic field component B2 on the first Hall 31. 垂直-2 It represents the vertical voltage generated by the parallel magnetic field component B2 on the second Hall 32. b1 and b2 are the second proportional constants corresponding to the first Hall 31 and the second Hall 32 respectively after adding the installation position error. When the differential Hall current sensor 100 is assembled, the value of the above second proportional constant is also determined.

[0163] When the interference magnetic field signal C is added, the total output voltages of the first Hall 31 and the second Hall 32 are respectively:

[0164] The total output voltage of the first Hall 31, V1 = a1*B1 + b1*B2 + C;

[0165] The total output voltage of the second Hall 32, V2 = -a2*B1 - b2*B2 + C;

[0166] Further calculate the differential signal between V1 and V2 , the calculation formula is as follows: .

[0167] It can be seen that the difference eliminates the interference. At the same time, it is known that B2 = k1*B1, then we can get:

[0168] Differential signaling , can be set , where K is the proportionality coefficient of current and voltage, which needs to be determined by calibrating the Hall effect. The first proportionality constants a1 and a2, the second proportionality constants b1 and b2, and the magnetic field proportionality coefficient k1 are all Hall’s inherent variables, which are determined by its factory configuration. In other words, as long as the differential signal is obtained, By calibrating the coefficient K between the current passing through the current bus and the Hall voltage, the current value I0 of the current to be measured input into the current bus 10 can be calculated.

[0169] According to another aspect of the present invention, an embodiment of the present invention further provides a method for manufacturing a differential Hall current sensor, which is used to manufacture the differential Hall current sensor described in the above aspects and embodiments. Taking the differential Hall current sensor 100 of Embodiment 1 as an example, the manufacturing method specifically includes:

[0170] Manufacturing current bus 10;

[0171] Manufacturing an insulating layer 20 and bonding the insulating layer 20 to the upper surface of the current bank 10;

[0172] At least two Halls 30 are symmetrically arranged on both sides of the upper surface of the insulating layer 20 along the current direction;

[0173] At least one deflection magnetic focusing block 40 is manufactured. The at least one deflection magnetic focusing block 40 is arranged close to the magnetic sensing surfaces of at least two Halls 30. The at least one deflection magnetic focusing block 40 is used to deflect the magnetic field component of the current magnetic field in the direction parallel to the magnetic sensing surface into the magnetic field component in the direction perpendicular to the magnetic sensing surface;

[0174] The coefficient K between the current flowing through the current row of each pair of Halls in at least two Halls 30 and the Hall voltage is obtained by calibration measurement.

[0175] In one example, by adjusting the specific process of the above manufacturing method or the specific details of manufacturing a certain component, a differential Hall current sensor such as the above embodiments 1 to 8 can be manufactured. For the structural differences of different embodiments in the manufacturing process, please refer to the description of the above embodiments, which will not be repeated here.

[0176] The differential Hall current sensor and the manufacturing method thereof provided by the embodiments of the present invention have at least one or part of the following advantages:

[0177] (1) The differential Hall current sensor and the manufacturing method thereof provided in the embodiments of the present invention gather the magnetic field generated by the current row to be measured by deflecting the magnetic concentrator to form a conductive magnetic circuit, thereby increasing the magnetic flux density;

[0178] (2) After the differential Hall current sensor and its manufacturing method provided by the embodiment of the present invention forms a conductive magnetic circuit by deflecting the magnetic concentrator, the direction of the magnetic field component parallel to the magnetic sensing surface of the Hall generated by the current row to be measured can be deflected to the same direction as the magnetic field component originally perpendicular to the magnetic sensing surface of the Hall, so that the Hall can obtain magnetic field components in two directions at the same time, thereby increasing the magnetic flux density of the magnetic field that can be sensed, thereby improving its measurement sensitivity;

[0179] (3) The differential Hall current sensor and its manufacturing method provided in the embodiment of the present invention further gathers the magnetic field generated by the current row to be measured by adding multiple deflection magnetic focusing blocks to a pair of Halls, thereby enhancing the magnetic field strength and improving the measurement sensitivity;

[0180] (4) The differential Hall current sensor and the manufacturing method thereof provided in the embodiments of the present invention package the current row to be measured together into the differential Hall current sensor, and fully utilize the current magnetic field by deflecting the magnetic focusing block. At the same time, there is no need to significantly narrow the width of the current row, thereby avoiding the heat caused by the narrowing of the current row, improving the reliability and environmental tolerance of the device, and helping to expand the measurement range to measure a current with a higher intensity;

[0181] (5) The differential Hall current sensor and the manufacturing method thereof provided in the embodiments of the present invention can flexibly set the number of deflection magnetic focusing blocks attached to the magnetic sensing surfaces of the paired Halls, the layout positions of the multiple deflection magnetic focusing blocks, and the cross-sectional shape of each deflection magnetic focusing block, and can use mature processing technology to manufacture the deflection magnetic focusing blocks, with a simple process and no additional manufacturing cost.

[0182] (6) The differential Hall current sensor and the manufacturing method thereof provided in the embodiments of the present invention arrange the Hall above the current row, and the spacing between the paired Halls can be reduced to zero, which can reduce the package size and greatly improve the anti-interference ability of the Hall.

[0183] (7) The differential Hall current sensor and the manufacturing method thereof provided in the embodiments of the present invention can arrange a differential Hall current sensor subunit at any position above the current row without affecting its signal gain and sensing performance, have a higher installation tolerance, and improve the flexibility of the installation layout;

[0184] (8) The differential Hall current sensor and the manufacturing method thereof provided in the embodiments of the present invention can appropriately arrange a certain number of differential Hall current sensor sub-units above the current bus, and improve the installation tolerance by balancing the signal gain between the differential Hall current sensor sub-units. There is no need to recalibrate the differential Hall current sensor during installation, thereby reducing the calibration workload;

[0185] (9) The differential Hall current sensor and the manufacturing method thereof provided in the embodiments of the present invention can further improve the measurement sensitivity of the differential Hall current sensor by properly arranging a plurality of differential Hall current sensor sub-units above the current bus.

[0186] Although some embodiments of the present general inventive concept have been shown and described, it will be appreciated by those skilled in the art that changes may be made to these embodiments without departing from the principles and spirit of the present general inventive concept, the scope of which is defined by the claims and their equivalents.

Claims

1. A differential Hall current sensor, characterized in that: The differential Hall current sensor comprises: Current bus; an insulating layer bonded to an upper surface of the current bus; At least two Hall elements are symmetrically arranged on both sides of the upper surface of the insulating layer along the current direction; At least one deflection magnetic focusing block is arranged close to the magnetic sensing surfaces of the at least two Halls, and the at least one deflection magnetic focusing block is used to deflect the magnetic field component of the current magnetic field in the direction parallel to the magnetic sensing surface into the magnetic field component in the direction perpendicular to the magnetic sensing surface.

2. The differential Hall current sensor according to claim 1, characterized in that: The current bus has a U-shaped structure with equal widths in each section, and both ends of the U-shaped structure are connected in series with an external current bus to be measured; The insulating layer is arranged on the upper surface of the bent section of the U-shaped structure or on the upper surface of any straight section of the U-shaped structure; The insulating layer, at least two Halls and at least one deflection magnetic focusing block form a differential Hall current sensor subunit; At least one of the differential Hall current sensor subunits is disposed at intervals on the upper surface of the current bus.

3. The differential Hall current sensor according to claim 2, characterized in that: An IC circuit board is further arranged on or in the insulating layer, and the at least two Halls output measurement signals after being differentiated by the IC circuit board; or The IC circuit board is separately arranged outside the current bus, and the at least two Halls are electrically connected to the IC circuit board through metal wires and output measurement signals after being differentiated by the IC circuit board.

4. The differential Hall current sensor according to any one of claims 1 to 3, characterized in that: The at least two Halls include at least one pair of Halls symmetrically arranged on both sides of the upper surface of the insulating layer about the center of the current row, and one pair of Halls in the at least one pair of Halls includes a first Hall and a second Hall arranged oppositely; In the pair of Halls, there is a first gap between the first Hall and the second Hall, and the first gap is set to a predetermined distance or equal to zero.

5. The differential Hall current sensor according to claim 4, characterized in that: With respect to the pair of Halls, the at least one deflection magnetic focusing block includes a first deflection magnetic focusing block centrally and symmetrically arranged above the pair of Halls, and the first deflection magnetic focusing block is respectively attached to the upper magnetic sensing surface of the pair of Halls and is located in the central area of ​​the Hall of the pair of Halls.

6. The differential Hall current sensor according to claim 5, characterized in that: For the pair of Halls, the first deflection magnetic focusing block is divided into a first part and a second part, the first part and the second part are respectively symmetrically attached to the upper magnetic sensing surfaces of the first Hall and the second Hall and are respectively located in the center area of ​​the first Hall and the second Hall; An end of the first portion away from the center of the current row is aligned with an edge of the current row on the same side; An end of the second portion away from the center of the current row is aligned with an edge of the current row on the same side; A second gap is defined between the first portion and the second portion.

7. The differential Hall current sensor according to claim 6, characterized in that: With respect to the pair of Halls, the at least one deflection magnetic focusing block further includes a second deflection magnetic focusing block centrally and symmetrically arranged below the pair of Halls, and the second deflection magnetic focusing blocks are respectively attached to the lower magnetic sensing surfaces of the pair of Halls; The first part and the second part of the first deflection magnetic focusing block are arranged on two sides close to the pair of Halls, and the second deflection magnetic focusing block is located in the middle area of ​​the pair of Halls; The first part of the first deflection magnetic focusing block, the second part of the first deflection magnetic focusing block and the second deflection magnetic focusing block are arranged symmetrically about the center of the current row and their plane projections coincide with the Hall center area of ​​the differential Hall current sensor.

8. The differential Hall current sensor according to claim 4, characterized in that: When any one of the at least one pair of Hall elements is an integrated Hall element, the pins of the integrated Hall element are directly soldered to the Hall element circuit of the IC circuit board and then connected to the signal processing circuit provided on the IC circuit board; or When any pair of the at least one pair of Halls is a Hall bare chip, the Hall bare chip is directly placed on the insulating layer, and is connected to the Hall chip circuit of the IC circuit board through a metal connection line, and then connected to the signal processing circuit provided on the IC circuit board; When the at least one pair of Halls are Hall bare chips and the first gap between the two Hall bare chips of each pair is equal to zero, a common ground electrode is set at the position where the two Hall bare chips contact each other, and the common ground electrode and the working electrodes of the two Hall bare chips respectively provide a working voltage for the Hall bare chips, and the Hall electrodes of the two Hall bare chips provide a differential Hall voltage.

9. The differential Hall current sensor according to claim 8, characterized in that: The cross-sectional shape of the at least one deflection magnetic focusing block is a centrally symmetrical shape, and the centrally symmetrical shape is any one of a rhombus, a square, a rectangle, a circle, an ellipse, or any combination thereof; The at least one deflection magnetic focusing block is provided with a contact structure at a position close to the magnetic sensing surface of the Hall, and the cross-sectional shape of the contact structure is any one of a circle, an ellipse, and a triangle, or any combination thereof; The material of the at least one deflection magnetic focusing block is a high magnetic permeability material that does not have magnetism itself, and the high magnetic permeability material is any one of ferrite, soft magnet, and nano-magnetic crystal; The material of each Hall in the at least two Halls is a Hall material, and the Hall material is any one of GaAs, InSb, and InAs; The at least one deflection magnetic focusing block is prepared by photolithography and sputtering and then fixedly connected by bonding; The current row, the insulating layer, at least two Halls and at least one deflection magnetic focusing block are packaged together through a packaging structure.

10. A method for manufacturing a differential Hall current sensor, for manufacturing the differential Hall current sensor according to claim 1, the manufacturing method comprising: Manufacturing current bars; manufacturing an insulating layer bonded to an upper surface of the current bus; At least two Hall electrodes are symmetrically arranged on both sides of the upper surface of the insulating layer along the current direction; Manufacturing at least one deflection magnetic focusing block, wherein the at least one deflection magnetic focusing block is disposed close to the magnetic sensing surfaces of the at least two Hall electrodes, and the at least one deflection magnetic focusing block is used to deflect the magnetic field component of the current magnetic field in a direction parallel to the magnetic sensing surfaces into a magnetic field component in a direction perpendicular to the magnetic sensing surfaces; The coefficient of the current flowing through the current row of each pair of Halls in at least two Halls and the Hall voltage is obtained by calibration measurement.

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