Current sensing chip

Abstract

The application discloses a current sensing chip, comprising: a substrate, which is formed with oppositely arranged first and second surfaces; a lead frame, which is used for guiding current outside the first and / or second surfaces of the substrate to form a current path; a magnetic field transducer, which is arranged on the first surface of the substrate or one side of the first surface; wherein the lead frame is formed with at least a surrounding part for partially surrounding the magnetic field transducer, the surrounding part is configured to have an opening to make the magnetic energy transducer at least partially exposed to the surrounding part in at least a preset direction; and the magnetic field transducer is an integrated circuit device made of at least a compound semiconductor. The application has the beneficial effect of providing a current sensing chip based on structural and material improvements to improve detection sensitivity.

Description

TECHNICAL FIELD

[0001] The present application relates to a current sensing chip. BACKGROUND

[0002] As is well known in the art, a conventional current sensing chip employs a magnetic field transducer (e.g. a Hall effect transducer or a magnetoresistive transducer) located in the vicinity of a current-carrying body. The output signal generated by the magnetic field transducer is proportional to the induced magnetic field of the current flowing through the current-carrying body.

[0003] The existing current sensing chip has low sensitivity due to structural and material problems. SUMMARY

[0004] The summary of the present application is used to introduce the concepts in a brief form, which will be described in detail in the following detailed description. The summary of the present application is not intended to identify key or essential features of the claimed technology solution, nor is it intended to limit the scope of the claimed technology solution.

[0005] Some embodiments of the present application provide a current sensing chip, comprising: a substrate formed with a first surface and a second surface arranged oppositely; a lead frame for guiding current outside the first surface and / or the second surface of the substrate to form a current path; a magnetic field transducer arranged on the first surface of the substrate or one side of the first surface; wherein the lead frame is formed with at least a surrounding portion for partially surrounding the magnetic field transducer, the surrounding portion is configured to have an opening to at least partially expose the magnetic field transducer from the surrounding portion in at least a predetermined direction; the magnetic field transducer is an integrated circuit device made of at least a compound semiconductor.

[0006] Further, the magnetic field transducer is at least configured as a transducer based on the Hall effect.

[0007] Further, the magnetic field transducer is at least configured as a transducer based on the magnetoresistance effect.

[0008] Further, the compound semiconductor at least includes indium antimonide.

[0009] Further, the compound semiconductor at least includes gallium arsenide.

[0010] Further, a conditioning chip is used to modulate the current or voltage loaded on the magnetic field transducer.

[0011] Further, the conditioning chip is an integrated circuit device made of silicon.

[0012] Further, the current sensing chip comprises two magnetic field transducers.

[0013] Further, the lead frame is formed with two encircling portions corresponding to the magnetic field transducer respectively, and the openings of the two encircling portions are configured to be arranged in different directions.

[0014] Further, the included angle between the directions of the openings of the two encircling portions ranges from 5 degrees to 85 degrees.

[0015] The current sensor chip based on the structural and material improvement provided by the present application has improved detection sensitivity. BRIEF DESCRIPTION OF DRAWINGS

[0016] The accompanying drawings, which form a part of the present application, are intended to provide further understanding of the present application, and are used in conjunction with the description given above to assist in the understanding of the present application. The accompanying drawings included in the present application serve to explain the present application, and do not constitute an undue limitation on the present application.

[0017] In addition, throughout the drawings, identical or similar reference numerals designate identical or similar elements. It should be understood that the drawings are schematic, and elements and elements are not necessarily drawn to scale.

[0018] In the drawings:

[0019] Figure 1 is a perspective structural schematic diagram of a current sensor chip according to a first embodiment of the present application;

[0020] Figure 2 is Figure 1 is an exploded structural schematic diagram of the current sensor chip shown in FIG. 1;

[0021] Figure 3 is Figure 2 is a planar layout schematic diagram of the current sensor chip shown in FIG. 1;

[0022] Figure 4 is Figure 3 is a partial enlarged view of the current sensor chip shown in FIG. 1;

[0023] Figure 5 is Figure 3 is a partial wiring schematic diagram of the current sensor chip shown in FIG. 1;

[0024] Figure 6 is a planar layout schematic diagram of a current sensor chip according to a second embodiment of the present application;

[0025] Figure 7 is a planar layout schematic diagram of a current sensor chip according to a third embodiment of the present application;

[0026] Figure 8 is a planar layout schematic diagram of a current sensor chip according to a fourth embodiment of the present application;

[0027] Figure 9 is a schematic diagram of a planar layout of a current sensing chip according to a fifth embodiment of the present application;

[0028] Figure 10 is a schematic diagram of a planar layout of a current sensing chip according to a sixth embodiment of the present application;

[0029] Figure 11 is a schematic diagram of a planar layout of a current sensing chip according to a seventh embodiment of the present application; Figure 10 is a partial enlarged view of the current sensing chip shown in

[0030] Figure 12 is a schematic diagram of a planar layout of a current sensing chip according to an eighth embodiment of the present application;

[0031] Figure 13 is a schematic diagram of a planar layout of a current sensing chip according to a ninth embodiment of the present application;

[0032] Figure 14 is a schematic diagram of a planar layout of a current sensing chip according to a tenth embodiment of the present application;

[0033] Figure 15 is a schematic diagram of a planar layout of a current sensing chip according to an eleventh embodiment of the present application;

[0034] Figure 16 is a schematic diagram of a planar layout of the embodiment shown in Figure 15 DETAILED DESCRIPTION

[0035] Embodiments of the present disclosure will be described in more detail with reference to the drawings. Although certain embodiments of the present disclosure are shown in the drawings, it is understood that the present disclosure can be embodied in various forms and should not be interpreted as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure can be more thoroughly and completely understood. It should be understood that the drawings of the present disclosure are only for illustrative purposes and should not be used to limit the scope of protection of the present disclosure.

[0036] It should also be noted that, for the sake of brevity, only the parts of the drawings that are relevant to the present application are shown. The embodiments in the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0037] It should be noted that the terms "first", "second", etc. mentioned in the present disclosure are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0038] ​It should be noted that the modification of "one", "a plurality of" mentioned in the present disclosure is illustrative rather than restrictive, and those skilled in the art should understand that unless the context clearly indicates otherwise, it should be understood as "one or more".

[0039] The names of the messages or information exchanged between the plurality of devices in the embodiments of the present disclosure are only for illustrative purposes, and are not intended to limit the scope of the messages or information.

[0040] The present disclosure will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0041] Referring to Figures 1 to 3 As shown in the drawings, the current sensing chip 100 of the present application comprises a substrate 20, a first type of lead frame 30, a second type of lead frame 40 and a plurality of magnetic field transducers.

[0042] As a preferred solution, the magnetic field transducers are at least configured as one Hall effect-based transducer or / and one magnetoresistance effect-based transducer.

[0043] The magnetic field transducers are integrated circuit devices made of at least compound semiconductors, which at least include indium antimonide or gallium arsenide.

[0044] The substrate 20 is configured as a plate structure in terms of shape, i.e. in the Figure 1 In the coordinate system, it has a large size in the X-axis and Y-axis directions and a small size in the Z-axis direction. More specifically, the substrate 20 is formed with oppositely arranged first and second surfaces 21 and 22, and the first and second surfaces 21 and 22 of the substrate 20 are configured as substantially flat surfaces, but are not limited to standard flat surfaces, and can form certain channels or protrusions on the first or second surface 21 or 22 due to the requirements of integrated circuit configuration.

[0045] The substrate 20 can be made of semiconductor materials such as silicon, and as an optional embodiment, the substrate 20 can also be made of insulating materials.

[0046] The first and second types of lead frames 30 and 40 can be made of conductive materials, which are used to guide current to form current paths or conductive bodies.

[0047] As a specific solution, the first type of lead frame 30 is used to form a first current path on one side of the first surface 21 of the substrate 20, and specifically, the first current path is used to form a corresponding magnetic field.

[0048] The first type of lead frame 30 comprises a first current guide 31, a second current guide 32, a first surrounding portion 33 and a second surrounding portion 34.

[0049] The first lead section 31 and the second lead section 32 serve as structures for connection to external circuits, thereby enabling the first type of lead frame 30 to be connected to an external current loop. Alternatively, the first lead section 31 or the second lead section 32 can be constructed to have a structure with multiple pins 41 to adapt to the corresponding external circuit.

[0050] Unlike the first drainage portion 31 and the second drainage portion 32, which are mainly formed outside the area covered by the substrate 20, the first surrounding portion 33 and the second surrounding portion 34 are mainly formed within the area covered by the substrate 20. Here, "the area covered by the substrate 20" refers to the area perpendicular to the substrate 20 (perpendicular to the approximate surface of the substrate 20). Figure 1 The projection of the substrate 20 is formed by projecting the substrate 20 along the Z-axis direction. Similarly, if other structures (such as the first surrounding portion 33) fall within the projection of the substrate 20 in that direction, then the structure is considered to be within the area covered by the substrate 20. Conversely, if other structures (such as the first drainage portion 31) do not fall within the projection of the substrate 20 in that direction, then the structure is considered to be outside the area covered by the substrate 20.

[0051] The first type of lead frame 30 is bonded to the first surface 21 of the substrate 20 such that the first surface 21 is close to the first type of lead frame 30, while the second surface 22 is away from the first type of lead frame 30. A magnetic field transducer is provided on the first surface 21 of the substrate 20, or a magnetic field transducer is disposed on one side of the first surface 21. As an alternative embodiment, the magnetic field transducer may be a Hall effect element. The magnetic field transducer is diffused to the first surface 21, or arranged on the first surface 21 such that the magnetic field transducer is close to the first type of lead frame 30.

[0052] The substrate 20 and the first type of lead frame 30 and the second type of lead frame are separated by an insulator 14, which can be arranged in various ways.

[0053] Reference Figures 1 to 3 As shown, a magnetic field transducer is provided in the area formed by the first surrounding portion 33 and the second surrounding portion 34, and the magnetic field transducer is positioned in a predetermined position relative to the first surrounding portion 33 and the second surrounding portion 34. The magnetic field transducer surrounded by the first surrounding portion 33 can be defined as the first magnetic field transducer 51, and the magnetic field transducer surrounded by the second surrounding portion 34 can be defined as the second magnetic field transducer 52.

[0054] The first looped part 33 has a first opening 331 facing the first direction, and the opening edge of the first opening 331 extends to a position surrounding the first magnetic field transducer 51. The second looped part 34 has a second opening 341 facing the second direction, and the opening edge of the second opening 341 extends to a position surrounding the second magnetic field transducer 52. The first direction is different from the second direction, so that the first magnetic field generated by the current flowing through the first looped part 33 and the second magnetic field generated by the current flowing through the second looped part 34 are in opposite directions, and the directions of the first magnetic field and the second magnetic field are substantially along the maximum response axis of the magnetic field transducer, i.e. in a predetermined position, the directions of the first magnetic field and the second magnetic field are along the Z-axis direction.

[0055] When there is an interference magnetic field, according to the direction of the interference magnetic field, the magnetic field strength passing through the first magnetic field transducer 51 and the second magnetic field transducer 52 will change, for example: when the direction of the interference magnetic field is the same as the current magnetic field passing through the first magnetic field transducer 51, the total magnetic field strength passing through the first magnetic field transducer 51 increases, and the total magnetic field strength passing through the second magnetic field transducer 52 also increases equally, so that the output signal of the first magnetic field transducer 51 and the output signal of the second magnetic field transducer 52 are equally large, and the two are subtracted to offset the influence of the interference magnetic field, thereby removing the interference of the interference magnetic field on the current detection result and improving the sensitivity.

[0056] The second type of lead frame 40 is used to receive the output signal of the magnetic field transducer, and specifically, to detect the current change on the first type of lead frame 30.

[0057] Referring to Figure 5 As shown, the second type of lead frame 40 has a conditioning chip, and the conditioning chip is connected between the magnetic field transducer through the first type of connecting line 11 and the second type of connecting line 12; the first type of connecting line 11 is used to input current to the magnetic field transducer, and the second type of connecting line is used to output the Hall voltage of the magnetic field transducer. The second type of lead frame 40 also has a plurality of pins 41, and the plurality of pins 41 are respectively connected with the conditioning chip through the third type of connecting line 13.

[0058] As an optional solution, the first direction and the second direction can be configured in the following manner: project the first type of lead frame 30 and the magnetic field transducer into an X-Y coordinate system, and mark two farthest boundary points at the opening of the first opening 331 and the second opening 341 respectively, and express the direction of the opening by the direction of the reference line passing through the midpoint of the line segment connecting the two farthest boundary points and the center point of the corresponding magnetic field transducer. The reference line expressing the first direction is L1, the reference line expressing the second direction is M1, and the angle between L1 and M1 is α1, which indicates the angle between the first direction and the second direction. The center point of the magnetic field transducer can be the intersection of the diagonal of the magnetic field transducer, or the center of the largest imaginary circle that can enclose the magnetic field transducer ("largest encirclement" means that the area of the second magnetic field transducer 52 in the imaginary circle is greater than half of the area of the imaginary circle).

[0059] Taking the second opening 341 as an example, the two farthest boundary points at the opening of the second opening 341 are A1 and B1 respectively, and the center point of the second magnetic field transducer 52 is O2. The straight line passing through the midpoint of the line segment A1B1 and O2 is taken as the reference line M1. In the same way, the reference line L1 passing through the center point O1 of the first magnetic field transducer 51 is drawn, and the angle between L1 and M1 is α1.

[0060] As a further solution, the boundary lines of the center point of the magnetic field transducer and the two farthest boundary points are drawn respectively, and the direction of the opening is expressed by the direction of the angle bisector of the two boundary lines corresponding to the center point of the same magnetic field transducer. The reference line expressing the first direction is L2, the reference line expressing the second direction is M2, and the angle between L2 and M2 is α2, which indicates the angle between the first direction and the second direction.

[0061] Taking the second opening 341 as an example, the boundary lines O2A1 and O2B1 are drawn by connecting the center point O2 of the second magnetic field transducer 52 and the farthest boundary points A1 and B1 respectively, and the straight line passing through the center point O2 and coinciding with the angle bisector of the boundary lines O2A1 and O2B1 is taken as the reference line M2. In the same way, the reference line L2 passing through the center point O1 of the first magnetic field transducer 51 is drawn, and the angle between L2 and M2 is α2.

[0062] As another optional solution, two nearest boundary points representing the first opening 331 and the second opening 341 are drawn respectively, and the direction of the opening is expressed by the direction of the reference line passing through the midpoint of the line segment connecting the two nearest boundary points and the center point of the corresponding magnetic field transducer. The reference line expressing the first direction is L3, the reference line expressing the second direction is M3, and the angle between L3 and M3 is α3, which indicates the angle between the first direction and the second direction.

[0063] Take the second opening 341 as an example, the two nearest boundary points of the opening of the second opening 341 are C1 and D1 respectively, and the center point of the second magnetic field transducer 52 is O2. A straight line passing through the line segment C1D1 and O2 is taken as the reference line M3. In the same way, a reference line L3 passing through the center point O1 of the first magnetic field transducer 51 is taken, and the included angle between L3 and M3 is α3.

[0064] As a preferred scheme, a straight line parallel to the opening edge of at least one straight line of the first opening 331 is taken as the reference line L4 that can represent the first direction, and a straight line parallel to the opening edge of at least one straight line of the second opening 341 is taken as the reference line M4 that can represent the second direction. The included angle α4 between L4 and M4 indicates the included angle between the first direction and the second direction.

[0065] Referring to Figure 3 and Figure 4 As shown in FIG. 1, as a first embodiment of the current sensing chip 100, the two opening edges of the first opening 331 are symmetrically arranged, that is, L1 to L4 coincide, an included angle α1 is formed between L1 and M1, an included angle α2 is formed between L2 and M2, an included angle α3 is formed between L3 and M3, and an included angle α4 is formed between L4 and M4. The values of α1, α2 and α3 are in the range of 5 degrees to 85 degrees, and the value of α4 is 90 degrees, that is, the included angle between the first direction and the second direction is 5 degrees to 85 degrees or 90 degrees.

[0066] Referring to Figure 6 As shown in FIG. 2, as a second embodiment of the current sensing chip 100, the second direction in this embodiment is changed from that in the first embodiment, and the included angle between the first direction and the second direction is 5 degrees to 85 degrees.

[0067] Referring to Figure 7 As shown in FIG. 3, as a third embodiment of the current sensing chip 100, the second direction in this embodiment is changed from that in the first embodiment, and the included angle between the first direction and the second direction is 5 degrees to 85 degrees.

[0068] Referring to Figure 8 As shown in FIG. 4, as a fourth embodiment of the current sensing chip 100, the second direction in this embodiment is changed from that in the first embodiment, and the included angle between the first direction and the second direction is 5 degrees to 85 degrees.

[0069] Referring to Figure 9 As shown in FIG. 5, as a fifth embodiment of the current sensing chip 100, the second direction in this embodiment is changed from that in the first embodiment, and the included angle between the first direction and the second direction is 5 degrees to 85 degrees.

[0070] Referring to Figure 10 and Figure 11As shown, as the sixth embodiment of the current sensing chip 100, in the embodiment, the opening edges of the first opening 331 are not completely symmetrically arranged, the two farthest boundary points of the opening of the first opening 331 are A2 and B2 respectively, the center point of the second magnetic field transducer 52 is O2, and a straight line passing through the midpoint of the line segment A2B2 and O2 is taken as the reference line L1. The center point O2 of the second magnetic field transducer 52 is connected with the farthest boundary points A2 and B2 respectively to obtain the boundary lines O2A2 and O2B2, and a straight line passing through the center point O2 and coinciding with the angle bisector of the boundary lines O2A2 and O2B2 is taken as the reference line L2. The two farthest boundary points of the opening of the first opening 331 are C2 and D2 respectively, and a straight line passing through the midpoint of the line segment C2D2 and O2 is taken as the reference line L3. A straight line parallel to the opening edge of at least one straight line of the first opening 331 is taken as the reference line L4 which can represent the first direction. An included angle α1 is formed between L1 and M1, an included angle α2 is formed between L2 and M2, an included angle α3 is formed between L3 and M3, and an included angle α4 is formed between L4 and M4. The values of α1, α2, α3 and α4 are in the range of 5 degrees to 85 degrees or 90 degrees, that is, the included angle between the first direction and the second direction is 5 degrees to 85 degrees or 90 degrees.

[0071] Referring to Figure 10 and Figure 11 As shown, as the seventh embodiment of the current sensing chip 100, in the embodiment, the second direction is changed compared with the sixth embodiment, and the included angle between the first direction and the second direction is 5 degrees to 85 degrees or 90 degrees.

[0072] Referring to Figure 12 As shown, as the eighth embodiment of the current sensing chip 100, in the embodiment, the second direction is changed compared with the sixth embodiment, and the included angle between the first direction and the second direction is 5 degrees to 85 degrees or 90 degrees.

[0073] Referring to Figure 13 As shown, as the ninth embodiment of the current sensing chip 100, in the embodiment, the second direction is changed compared with the sixth embodiment, and the included angle between the first direction and the second direction is 5 degrees to 85 degrees or 90 degrees.

[0074] Referring to Figure 14 As shown, as the ninth embodiment of the current sensing chip 100, the first direction can be constructed to be parallel to the second direction, however, the current sensing chip 100 arranged in this way has a too complex structure.

[0075] The application also provides a current sensor comprising the aforementioned current sensing chip 100.

[0076] Referring to Figure 15 and Figure 16As shown, in contrast to the previously described embodiments, the current sensor has only one magnetic field transducer 53 in its chip, and is provided with a conditioning chip 54 for modulating the current or voltage applied to the magnetic field transducer 53, the conditioning chip 54 being an integrated circuit device made of silicon.

[0077] The leadframe 30a is used to guide the current outside the first and / or second surface of the substrate to form a current path, wherein the leadframe 30a comprises a first current lead 31, a second current lead 32, and a surrounding portion 35; the surrounding portion 35 is formed between the first current lead 31 and the second current lead 32, and is arranged at least partially around the magnetic field transducer 53, and the surrounding portion 35 is configured to have an opening 351 to expose the magnetic field transducer 53 at least partially outside the surrounding portion 35 at least in a predetermined direction.

[0078] As a preferred solution, the magnetic field transducer 53 is an integrated circuit device made of at least a compound semiconductor, wherein the compound semiconductor at least comprises indium antimonide and gallium arsenide.

[0079] As a preferred solution, the magnetic field transducer is at least configured as a transducer based on the Hall effect, or at least configured as a transducer based on the magnetoresistance effect.

[0080] The above description is merely some preferred embodiments of the present disclosure and an explanation of the principles of the technology applied. Those skilled in the art should understand that the scope of the invention involved in the embodiments of the present disclosure is not limited to the technical solutions formed by the specific combinations of the above technical features, and should also cover other technical solutions formed by any combinations of the above technical features or equivalent features without departing from the above inventive concept. For example, the above features are replaced with the technical features disclosed in the embodiments of the present disclosure (but not limited to) having similar functions to form technical solutions.

Claims

1.A current sensing chip, characterized in that: the current sensing chip comprises: a substrate formed with a first surface and a second surface arranged oppositely; a lead frame for guiding current outside the first surface and / or the second surface of the substrate to form a current path; a magnetic field transducer arranged on the first surface of the substrate or one side of the first surface; wherein the lead frame is formed with at least a surrounding portion for partially surrounding the magnetic field transducer, the surrounding portion is configured to have an opening to make the magnetic field transducer at least partially exposed to the surrounding portion in at least a preset direction; the magnetic field transducer is an integrated circuit device made of at least a compound semiconductor; the lead frame is formed with two surrounding portions corresponding to the magnetic field transducer respectively, the openings of the two surrounding portions are configured to be arranged in different directions; the first direction and the second direction can be configured in the following manner: projecting the first type of lead frame and the magnetic field transducer into an X-Y coordinate system, respectively making two farthest boundary points of the openings of the first opening and the second opening, and representing the direction of the opening by the direction of the reference line between the midpoint of the connecting segment of the two farthest boundary points and the center point of the corresponding magnetic field transducer, the included angle between the directions of the openings ranges from 5 degrees to 85 degrees. 2.The current sensing chip according to claim 1, characterized in that: the magnetic field transducer is at least configured as a transducer based on the Hall effect. 3.The current sensing chip according to claim 1, characterized in that: the magnetic field transducer is at least configured as a transducer based on the magnetoresistance effect. 4.The current sensing chip according to claim 1, characterized in that: the compound semiconductor at least comprises indium antimonide. 5.The current sensing chip according to claim 1, characterized in that: the compound semiconductor at least comprises gallium arsenide. 6.The current sensing chip according to claim 1, characterized in that: the current sensing chip further comprises: a conditioning chip for modulating the current or voltage loaded on the magnetic field transducer. 7.The current sensing chip according to claim 6, characterized in that: the conditioning chip is an integrated circuit device made of silicon. 8.The current sensing chip according to claim 1, characterized in that: the current sensing chip comprises two magnetic field transducers.

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