Multi-path current difference detection device

Abstract

To provide a multi-path current difference detection device.SOLUTION: A multi-path current difference detection device 100 includes a sensing element 11 and a determination unit 12. The sensing element 11 senses multiple currents i1, i2 flowing through multiple paths Pi1, Pi2 and calculates a net current value of multiple current values of these currents. The determination unit 12 receives a current signal Sin corresponding to the net current value, determines that the current signal Sin is equal to or greater than a current threshold, and supplies a detection signal Sdet.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a current difference detection device, and more particularly to a multi-path current difference detection device. [Background technology]

[0002] Currently, it is common to use current transformers (CTs) to detect different current directions in two or more paths. However, current transformers have the disadvantages of being large, requiring complex circuits, and being expensive. Furthermore, when used to detect current, current transformers are susceptible to temperature effects, which can cause accuracy drift. Therefore, in addition to current transformers, Hall sensors are also used for current detection. However, because one Hall sensor can only be used to detect the current in one path, detecting different current directions in two or more paths requires the use of more Hall sensors, which increases costs. Summary of the Invention [Problem to be solved by the invention]

[0003] Therefore, how to design a multi-path current difference detection device that solves the problems and technical bottlenecks of the existing technology is an important topic that the inventors of the present application are studying. [Means for solving the problem]

[0004] An object of the present invention is to provide a multi-path current difference detection device. The multi-path current difference detection device includes a sensing element and a determination unit. The sensing element senses multiple currents flowing through multiple paths and calculates a net current value of the multiple current values of these currents. The determination unit receives a current signal corresponding to the net current value, determines that the current signal is equal to or greater than a current threshold, and provides a detection signal.

[0005] In one embodiment, the determination unit includes a signal amplifier and a voltage follower. The signal amplifier receives and amplifies the current signal. The voltage follower is connected to the signal amplifier and receives the amplified current signal. The voltage follower provides a high-level detection signal based on the amplified current signal being equal to or greater than a current threshold. The voltage follower provides a low-level detection signal based on the amplified current signal being less than the current threshold.

[0006] In one embodiment, the differential current sensing device is an integrated circuit.

[0007] In one embodiment, the current value corresponding to the current threshold is zero amperes.

[0008] In one embodiment, each current is an alternating current, and the current value corresponding to the current threshold is 15 milliamps.

[0009] In one embodiment, each current is an AC current or a DC current, and the current value corresponding to the current threshold is 3 to 6 milliamps DC.

[0010] In one embodiment, the sensing element is a Hall element, a tunneling magnetoresistance, anisotropic magnetoresistance, giant magnetoresistance, colossal magnetoresistance, normal magnetoresistance, or a shunt resistor.

[0011] In one embodiment, the signal amplifier is an operational amplifier.

[0012] In one embodiment, the differential current sensing device is mounted on a circuit board that is a stack of laminates, with the paths being located on different laminates.

[0013] Another object of the present invention is to provide a multi-path current difference detection device. The multi-path current difference detection device includes a sensing element and a determination unit. The sensing element senses multiple currents flowing through multiple paths. The determination unit receives multiple current signals corresponding to multiple current values of the currents, calculates a net current of the current values, determines that the net current signal corresponding to the net current is equal to or greater than a current threshold, and provides a detection signal.

[0014] In one embodiment, the determination unit includes a plurality of signal amplifiers, a plurality of voltage followers, and a calculation unit. The signal amplifiers receive and amplify the current signals, respectively. The voltage followers are connected to the signal amplifiers and receive the amplified current signals, respectively. The calculation units are connected to the voltage followers and receive the amplified current signals, respectively, and add the current signals to generate a net current signal corresponding to the net current. The calculation unit provides a high-level detection signal based on the net current signal being equal to or greater than a current threshold. The calculation unit provides a low-level detection signal based on the net current signal being less than the current threshold.

[0015] In one embodiment, the differential current sensing device is an integrated circuit.

[0016] In one embodiment, the current value corresponding to the current threshold is zero amperes.

[0017] In one embodiment, each current is an alternating current, and the current value corresponding to the current threshold is 15 milliamps.

[0018] In one embodiment, each current is an AC current or a DC current, and the current value corresponding to the current threshold is 3 to 6 milliamps DC.

[0019] In one embodiment, the sensing element is a Hall element, a tunneling magnetoresistance, anisotropic magnetoresistance, giant magnetoresistance, colossal magnetoresistance, normal magnetoresistance, or a shunt resistor.

[0020] In one embodiment, the signal amplifier is an operational amplifier.

[0021] In one embodiment, the differential current sensing device is mounted on a circuit board that is a stack of laminates, with the paths being located on different laminates. [Effects of the Invention]

[0022] As a result, the multi-path current difference detection device proposed by the present invention has the following features and advantages: (1) The current difference detection device of the present invention can be realized as a packaged integrated circuit, thereby significantly reducing the volume and space occupied. (2) The current difference detection device of the present invention can detect multi-path current differences contactlessly or contactlessly. (3) The current difference detection device of the present invention can be used to detect AC or DC current. (4) In a preferred embodiment, it can accurately detect AC current differences of 15 milliamperes or more, or DC current differences of 6 milliamperes or more and 3 milliamperes or less. (5) The pitch design of the different current paths can avoid electromagnetic interference. (6) The detection time of the current difference detection according to the present invention can be reduced to less than 1 second. (7) The detection accuracy of the current difference detection according to the present invention is higher than 95% (i.e., the error is less than 5%). (8) The current difference detection device of the present invention can operate in an environment higher than 150°C. (9) In the present invention, the pitch of multiple laminates having a stacked structure on a circuit board can be 0.4±0.1 millimeters.

[0023] To better understand the techniques, means and advantages of the present invention, which are adopted by the present invention to achieve the specified objects, please refer to the following detailed description of the present invention and the drawings, which are believed to provide a deeper and more specific understanding of the objects, features and characteristics of the present invention, but the accompanying drawings are provided for reference and explanation only and are not intended to limit the present invention. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 1 is a schematic diagram showing a conventional current transformer used for current detection. [Figure 2] 1 is a block diagram of a first embodiment of a multi-path current difference detection device according to the present invention. [Figure 3] 1 is a circuit block diagram of a first embodiment of a multi-path current difference detection device according to the present invention. [Figure 4] 1 is a schematic diagram of a first example of a first embodiment of a multi-path current difference detection device according to the present invention realized as an integrated circuit; [Figure 5] 2 is a schematic diagram of a second example of the first embodiment of the multi-path current difference detection device according to the present invention realized as an integrated circuit; FIG. [Figure 6A] 1 is a schematic diagram of a multi-path current difference detection device according to the present invention applied to a circuit board with a laminated structure; [Figure 6B] 1 is a schematic diagram of a multi-path current difference detection device according to the present invention applied to a circuit board with a laminated structure; [Figure 6C] 1 is a schematic diagram of a multi-path current difference detection device according to the present invention applied to a circuit board with a laminated structure; [Figure 7] FIG. 4 is a block diagram of a second embodiment of a multi-path current difference detection device according to the present invention. [Figure 8] FIG. 4 is a circuit block diagram of a second embodiment of a multi-path current difference detection device according to the present invention. [Figure 9] 4 is a schematic diagram of a second embodiment of a multi-path current difference detection device according to the present invention implemented as an integrated circuit; FIG. DETAILED DESCRIPTION OF THE INVENTION

[0025] The technical contents and detailed description of the present invention will be explained below in conjunction with the drawings.

[0026] The following describes the embodiments of the present invention through certain specific embodiments, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. In addition, the present invention can be implemented or applied through other different specific examples, and various details in the specification of the present invention can be variously modified and changed based on different viewpoints and applications without departing from the gist of the present invention.

[0027] The structures, ratios, sizes, number of elements, etc. shown in the drawings attached to this specification are not intended to limit the conditions under which the present invention can be implemented, but are merely provided together with the contents disclosed in this specification for the understanding of those skilled in the art, and therefore do not have any substantial technical significance. Any structural modifications, changes in ratio relationships, or adjustments in size are included in the scope of the technical contents disclosed in this specification to the extent that they do not impair the effects or objectives that can be achieved by this invention.

[0028] Fig. 2 is a block diagram of a first embodiment of a multi-path current difference detection device according to the present invention. First, as shown in Fig. 2, the above-mentioned "multi-path" refers to a plurality of paths through which a current flows, and does not limit the direction of current flow (flow direction) in each of the paths.

[0029] The first embodiment of the multi-path current difference detection device 100 shown in Fig. 2 includes a sensing element 11 and a determination unit 12. Each sensing element 11 has a function of generating a magnetic field by sensing a current, and can generate an electric signal (for example, but not limited to, a voltage signal) according to the magnitude of the sensed current and the corresponding change in the magnetic field. Therefore, the magnitude of all the currents sensed in the multi-paths or the magnitude of the net current can be determined according to the magnitude of the electric signal. In the present invention, each of the sensing elements 11 may be a Hall element, a tunnel magnetoresistance (TMR), an anisotropic magnetoresistance (AMR), a giant magnetoresistance (GMR), a colossal magnetoresistance (CMR), an ordinary magnetoresistance (OMR), or a shunt resistor, but is not limited to these elements. Any element that can be used to achieve the above functions and purposes can be used as the sensing element 11, and they are included in the scope of the technical content disclosed in the present invention.

[0030] The current difference detection device 100 is an integrated circuit (IC). That is, the current difference detection device 100 can be realized as a packaged integrated circuit, which allows for a significant reduction in the volume and space occupied.

[0031] The sensing element 11 is used to sense multiple currents i1 and i2 flowing through multiple paths Pi1 and Pi2. FIG. 2 illustrates two paths, i.e., a first path Pi1 and a second path Pi2, so the sensing element 11 can be used to sense the magnitude of a first current i1 flowing through the first path Pi1 and the magnitude of a second current i2 flowing through the second path Pi2. In the present invention, the sensing element 11 can also be used to sense the magnitude of currents through two or more paths, but this will not be repeated here. The sensing element 11 calculates a net current value |i1-i2| of the multiple current values of these currents i1 and i2 based on the magnitude of the first current i1 and the magnitude of the second current i2. In other words, the net current calculated by the sensing element 11 is |i1-i2| or |i2-i1|, which means that only the magnitude of the net current value is considered, regardless of the flow direction of the first current i1 and the second current i2. Incidentally, when calculating the net current of the three currents, the net current is |i1-i2-i3| or the absolute value of the subtraction of the three currents.

[0032] The judgment unit 12 is connected to the sensing element 11 and receives the current signal Sin corresponding to the net current value |i1-i2|. The judgment unit 12 determines that the current signal Sin is equal to or greater than the current threshold and outputs a detection signal Sdet. Specifically, since the net current value |i1-i2| is the actual current value, the sensing element 11 converts the actual current value into the corresponding current signal Sin. In other words, the larger the current signal Sin, the larger the net current value |i1-i2|. Conversely, the smaller the current signal Sin, the smaller the net current value |i1-i2|. Therefore, the judgment unit 12 receives the current threshold and compares the current signal Sin with the current threshold. If the judgment unit 12 determines that the current signal Sin is equal to or greater than the current threshold, it outputs a detection signal Sdet.

[0033] Incidentally, the sensing element 11 can be used to sense AC or DC current. Accordingly, in one embodiment, the current value corresponding to the current threshold is zero amperes. That is, when the current signal Sin is equal to or greater than zero amperes (i.e., the current threshold), the determination unit 12 outputs the detection signal Sdet, which indicates that the net current value |i1-i2| of the first current i1 and the second current i2 is not zero, and thus it can be determined that a non-zero DC or AC current difference exists between these paths Pi1 and Pi2.

[0034] In another embodiment, since the first current i1 and the second current i2 are AC currents and the current value corresponding to the current threshold is 15 milliamperes, when the current signal Sin is equal to or greater than 15 milliamperes (i.e., the current threshold), the determination unit 12 outputs the detection signal Sdet indicating that the net current value |i1-i2| of the first current i1 and the second current i2 is equal to or greater than 15 milliamperes, and therefore it can be determined that an AC current difference of 15 milliamperes or greater exists between these paths Pi1 and Pi2.

[0035] Similarly, in another embodiment, when the first current i1 and the second current i2 are AC current or DC current and the current value corresponding to the current threshold is 3 to 6 milliamperes DC, and the current signal Sin is greater than 6 milliamperes or less than 3 milliamperes (i.e., the current threshold), the determination unit 12 outputs the detection signal Sdet indicating that the net current value |i1-i2| of the first current i1 and the second current i2 is greater than 6 milliamperes or less than 3 milliamperes, and therefore it can be determined that a DC current difference of greater than 6 milliamperes or less than 3 milliamperes exists between these paths Pi1 and Pi2.

[0036] FIG. 3 is a circuit block diagram of a first embodiment of a multi-path current difference detection apparatus according to the present invention. FIG. 3 further discloses and describes an embodiment of the determination unit 12. As shown in FIG. 3, the determination unit 12 includes a signal amplifier 121 and a voltage follower 122. The signal amplifier 121 receives the current signal Sin and amplifies the current signal Sin. In one embodiment, the signal amplifier 121 is an operational amplifier (OPA). Therefore, the signal amplifier 121 receives the current signal Sin and amplifies it to generate a corresponding voltage signal through the operation of the operational amplifier. The voltage follower 122 is connected to the signal amplifier 121 and receives the amplified current signal Sin, i.e., the voltage signal generated by the signal amplifier 121.

[0037] The determination unit 12 outputs a high-level detection signal Sdet via the voltage follower 122 based on the amplified current signal Sin being equal to or greater than the current threshold. As described above, when the current value corresponding to the current threshold is zero amperes and the voltage follower 122 outputs a high-level detection signal Sdet, it indicates that the net current value |i1-i2| of the first current i1 and the second current i2 is not zero, and it can be determined that a non-zero DC or AC current difference exists between these paths Pi1 and Pi2. When the current value corresponding to the current threshold is 15 milliamperes and the voltage follower 122 outputs a high-level detection signal Sdet, it indicates that the net current value |i1-i2| of the first current i1 and the second current i2 is not less than 15 milliamperes, and it can be determined that an AC current difference of not less than 15 milliamperes exists between these paths Pi1 and Pi2. When the current value corresponding to the current threshold is 3 to 6 milliamperes and the voltage follower 122 outputs a high-level detection signal Sdet, it indicates that the net current value |i1-i2| of the first current i1 and the second current i2 is 6 milliamperes or more or 3 milliamperes or less, so it can be determined that there is a DC current difference of 6 milliamperes or more or 3 milliamperes or less between these paths Pi1 and Pi2.

[0038] Conversely, the determination unit 12 outputs a low-level detection signal Sdet via the voltage follower 122 based on the amplified current signal Sin being less than the current threshold. As described above, when the current value corresponding to the current threshold is zero amperes and the voltage follower 122 outputs a low-level detection signal Sdet, it indicates that the net current value |i1-i2| of the first current i1 and the second current i2 is zero, and it can be determined that there is no DC or AC current difference between these paths Pi1 and Pi2. When the current value corresponding to the current threshold is 15 milliamperes and the voltage follower 122 outputs a low-level detection signal Sdet, it indicates that the net current value |i1-i2| of the first current i1 and the second current i2 is less than 15 milliamperes, and it can be determined that there is no AC current difference of 15 milliamperes or more between these paths Pi1 and Pi2. When the current value corresponding to the current threshold is 3 to 6 milliamperes and the voltage follower 122 outputs a low-level detection signal Sdet, it indicates that the net current value |i1-i2| of the first current i1 and the second current i2 is less than 6 milliamperes or exceeds 3 milliamperes, so it can be determined that there is no DC current difference of 6 milliamperes or more or 3 milliamperes or less between these paths Pi1 and Pi2.

[0039] However, the present invention is not limited to determining that the net current value |i1-i2| is equal to or greater than the current threshold value when the detection signal Sdet is at a high level, and determining that the net current value |i1-i2| is less than the current threshold value when the detection signal Sdet is at a low level. In other words, the relationship between the net current value |i1-i2| and the current threshold value can be determined by inverted signal levels. For example, if the current threshold is set to zero amperes and the voltage follower 122 outputs a low-level detection signal Sdet, it may indicate that the net current value |i1-i2| of the first current i1 and the second current i2 is not zero. Conversely, if the voltage follower 122 outputs a high-level detection signal Sdet, it may indicate that the net current value |i1-i2| of the first current i1 and the second current i2 is zero.

[0040] FIG. 4 is a schematic diagram of a first example of a first embodiment of a multi-path current difference detection device according to the present invention, which is implemented as an integrated circuit. As described above, the current difference detection device 100 can be implemented as a packaged integrated circuit. Therefore, in FIG. 4, the current difference detection device 100 is an integrated circuit for multi-path current difference detection. The current difference detection device 100 is contactlessly attached to a first path Pi1 and a second path Pi2, both of which are traces on a bus (also called a bus bar, bus board, or bus bar) or a printed circuit board (PCB). Since FIG. 4 uses a bus as an example, the top view (plan view) shown in FIG. 4 shows that the current difference detection device 100 is contactlessly attached to the first path Pi1 and the second path Pi2 of the bus. A first current i1 flowing through the first path Pi1 and a second current i2 flowing through the second path Pi2 are sensed by a sensing element 11. The sensing element 11 calculates a net current value |i1-i2| of the first current i1 and the second current i2. The determination unit 12 receives a current signal Sin corresponding to the net current value |i1-i2|, determines that the current signal Sin is equal to or greater than a current threshold, and supplies a detection signal Sdet. As shown in FIG. 4, the current difference detection device 100 can output the detection signal Sdet as an output voltage Vout via an output terminal Out. Furthermore, the current difference detection device 100 can be supplied with necessary power from an externally supplied power supply voltage Vcc.

[0041] FIG. 5 is a schematic diagram of a second example of the first embodiment of the multi-path current difference detection device according to the present invention, implemented as an integrated circuit. Because FIG. 5 uses a bus as an example, the top view (plan view) in FIG. 5 shows that the current difference detection device 100 is non-contactingly attached to a first path Pi1 and a second path Pi2 of the bus. A first current i1 flowing through the first path Pi1 and a second current i2 flowing through the second path Pi2 are sensed by a sensing element 11. The sensing element 11 also calculates a net current value |i1-i2| of the first current i1 and the second current i2. A determination unit 12 receives a current signal Sin corresponding to the net current value |i1-i2|, determines that the current signal Sin is equal to or greater than a current threshold, and provides a detection signal Sdet. As shown in FIG. 5, the current difference detection device 100 can output the detection signal Sdet as an output voltage Vout via an output terminal Out. Furthermore, the current difference detecting device 100 can be supplied with necessary power from an externally supplied power supply voltage Vcc.

[0042] 6A to 6C are schematic diagrams of a multi-path current difference detection device according to the present invention, each applied to a laminated circuit board. The contents shown in FIGS. 6A to 6C clearly and conveniently illustrate the current difference detection device 100 applied to a laminated circuit board. The current difference detection device 100 is provided on a circuit board having a laminated structure, which is a plurality of laminates, and the paths Pi1 and Pi2 are respectively disposed on different laminates. As shown in FIG. 6A, the circuit board includes two laminates, i.e., a first laminate L1 and a second laminate L2, and the first path Pi1 is disposed on the first laminate L1, and the second path Pi2 is disposed on the second laminate L2. The current difference detection device 100 is provided in a non-contact manner on the first path Pi1 and the second path Pi2 and is electrically connected to the first laminate L1 of the circuit board. Therefore, according to the aforementioned technical means, the sensing element 11 and the judgment unit 12 are used to realize multi-path current difference detection, which will not be repeated here.

[0043] As shown in Figure 6B, the circuit board includes four laminates: a first laminate L1, a second laminate L2, a third laminate L3, and a fourth laminate L4. The first path Pi1 is disposed on the second laminate L2, and the second path Pi2 is disposed on the third laminate L3. However, the number of paths and the laminate positions on which they are disposed are not limited to the above-described embodiment. The current difference detection device 100 is non-contactingly attached to the first path Pi1 and the second path Pi2 and electrically connected to the first laminate L1 of the circuit board. Therefore, according to the above-described technical means, the sensing element 11 and the judgment unit 12 are used to realize multi-path current difference detection, which will not be repeated here.

[0044] 6C, the circuit board includes six laminates: a first laminate L1, a second laminate L2, a third laminate L3, a fourth laminate L4, a fifth laminate L5, and a sixth laminate L6. The first path Pi1 is disposed on the second laminate L2, the second path Pi2 is disposed on the third laminate L3, the third path Pi3 is disposed on the fourth laminate L4, and the fourth path Pi4 is disposed on the fifth laminate L5. However, the number of paths and the positions of the laminates on which they are disposed are not limited thereto. The current difference detection device 100 is non-contactingly provided on the first path Pi1, the second path Pi2, the third path Pi3, and the fourth path Pi4 and is electrically connected to the first laminate L1 of the circuit board. Therefore, according to the aforementioned technical means, the sensing element 11 and the judgment unit 12 are used to realize multi-path current difference detection, which will not be repeated here.

[0045] FIG. 7 is a block diagram of a second embodiment of a multi-path current difference detection device according to the present invention. The multi-path current difference detection device 200 of the second embodiment shown in FIG. 7 includes a sensing element 21 and a determination unit 22. Unlike the contactless detection of the first embodiment shown in FIG. 2, the current difference detection device 200 of this embodiment performs contact detection, so the sensing element 21 directly senses the magnitude of the current. In the present invention, each sensing element 21 is a Hall element, tunnel magnetoresistance (TMR), anisotropic magnetoresistance (AMR), giant magnetoresistance (GMR), colossal magnetoresistance (CMR), ordinary magnetoresistance (OMR), or shunt resistor, but the present invention is not limited to these elements.

[0046] The current difference detection device 200 is an integrated circuit (IC), that is, can be realized as a packaged integrated circuit, thereby significantly reducing the volume and space occupied.

[0047] The sensing element 21 receives multiple currents i1, i2 flowing through multiple paths Pi1, Pi2, and in the example of two paths shown in Figure 7, it receives the magnitude of the first current i1 flowing through the first path Pi1 and the magnitude of the second current i2 flowing through the second path Pi2. In the present invention, the sensing element 21 can also be used to receive the current magnitudes of more than two paths, but this will not be repeated here.

[0048] The determination unit 22 is connected to the sensing element 21 and receives a plurality of current signals Sin1, Sin2 corresponding to a plurality of current values of the currents i1, i2. In other words, the determination unit 22 receives a first current signal Sin1 corresponding to a current value of the first current i1 and a second current signal Sin2 corresponding to a current value of the second current i2. Furthermore, the determination unit 22 calculates a net current |i1-i2| of the current value of the first current i1 and the current value of the second current i2. That is, the net current calculated by the determination unit 22 is |i1-i2| or |i2-i1|, which means that only the magnitude of the net current value is taken into account, without taking into account the flow direction of the first current i1 and the second current i2.

[0049] The determination unit 22 determines that the net current signal corresponding to the net current |i1-i2| is greater than or equal to the current threshold, and provides a detection signal Sdet. Specifically, the sensing element 21 converts the actual current value of the first current i1 into a corresponding first current signal Sin1 (i.e., the larger the first current signal Sin1, the larger the first current i1, and vice versa), and converts the actual current value of the second current i2 into a corresponding second current signal Sin2 (i.e., the larger the second current signal Sin2, the larger the second current i2, and vice versa), and provides them to the determination unit 22. Therefore, the determination unit 22 calculates the net current of the first current i1 and the second current i2 according to the first current signal Sin1 and the second current signal Sin2. Therefore, the determination unit 22 receives the current threshold and compares the net current signal corresponding to the net current |i1-i2| with the current threshold. If the determining unit 12 determines that the net current signal is greater than or equal to the current threshold, it provides a detection signal Sdet.

[0050] Incidentally, the sensing element 21 can be used to sense AC or DC current. Accordingly, in one embodiment, the current value corresponding to the current threshold is zero amperes. That is, when the net current signal is equal to or greater than zero amperes (i.e., the current threshold), the determination unit 22 outputs the detection signal Sdet, indicating that the net current value |i1-i2| of the first current i1 and the second current i2 is not zero, and thus it can be determined that a non-zero DC or AC current difference exists between these paths Pi1 and Pi2.

[0051] In another embodiment, since the first current i1 and the second current i2 are AC currents and the current value corresponding to the current threshold is 15 milliamperes, when the net current signal is equal to or greater than 15 milliamperes (i.e., the current threshold), the determination unit 22 outputs the detection signal Sdet indicating that the net current value |i1-i2| of the first current i1 and the second current i2 is equal to or greater than 15 milliamperes, and therefore it can be determined that there is an AC current difference of 15 milliamperes or greater between these paths Pi1 and Pi2.

[0052] Similarly, in another embodiment, when the first current i1 and the second current i2 are AC current or DC current and the current value corresponding to the current threshold is 3 to 6 milliamperes DC, and therefore the net current signal is greater than 6 milliamperes or less than 3 milliamperes (i.e., the current threshold), the determination unit 22 outputs the detection signal Sdet indicating that the net current value |i1-i2| of the first current i1 and the second current i2 is greater than 6 milliamperes or less than 3 milliamperes, and therefore it can be determined that a DC current difference of greater than 6 milliamperes or less than 3 milliamperes exists between these paths Pi1 and Pi2.

[0053] FIG. 8 is a circuit block diagram of a second embodiment of a multi-path current difference detection device according to the present invention. FIG. 8 further discloses and describes an embodiment of the determination unit 22. As shown in FIG. 8, the determination unit 22 includes a plurality of signal amplifiers 221-1 and 221-2, a plurality of voltage followers 222-1 and 222-2, and a calculation unit 223. The signal amplifiers 221-1 and 221-2 receive the current signals Sin1 and Sin2, respectively, and amplify the current signals Sin1 and Sin2, respectively. In one embodiment, each signal amplifier is an operational amplifier (OPA). Accordingly, the first signal amplifier 221-1 receives the first current signal Sin1 and amplifies the first current signal Sin1 through the operation of the operational amplifier, and the second signal amplifier 221-2 receives the second current signal Sin2 and amplifies the second current signal Sin2 through the operation of the operational amplifier.

[0054] A plurality of voltage followers 222-1, 222-2 are connected to the signal amplifiers 221-1, 221-2 corresponding to each other and receive the amplified current signals Sin1, Sin2, respectively. Specifically, the first voltage follower 222-1 is connected to the first signal amplifier 221-1 and receives the amplified first current signal Sin1, and the second voltage follower 222-2 is connected to the second signal amplifier 221-2 and receives the amplified second current signal Sin2.

[0055] The calculation unit 223 is connected to the voltage followers 222-1 and 222-2, receives the amplified current signals Sin1 and Sin2, and adds the current signals Sin1 and Sin2 to generate a net current signal corresponding to the net current. Specifically, the calculation unit 223 is connected to the first voltage follower 222-1 and the second voltage follower 222-2, receives the amplified first current signal Sin1 and the amplified second current signal Sin2, and adds the amplified first current signal Sin1 and the amplified second current signal Sin2 to further generate a net current signal corresponding to the net current |i1-i2|.

[0056] The determination unit 22 provides a high-level detection signal Sdet to the calculation unit 223 based on the net current signal being equal to or greater than the current threshold. As described above, when the current value corresponding to the current threshold is zero amperes and the calculation unit 223 outputs a high-level detection signal Sdet, it indicates that the net current value |i1-i2| between the first current i1 and the second current i2 is not zero, and it can be determined that a non-zero DC or AC current difference exists between these paths Pi1 and Pi2. When the current value corresponding to the current threshold is 15 milliamperes and the calculation unit 223 outputs a high-level detection signal Sdet, it indicates that the net current value |i1-i2| between the first current i1 and the second current i2 is not less than 15 milliamperes, and it can be determined that an AC current difference of not less than 15 milliamperes exists between these paths Pi1 and Pi2. If the current value corresponding to the current threshold is 3 to 6 milliamperes and the calculation unit 223 outputs a high-level detection signal Sdet, it indicates that the net current value |i1-i2| of the first current i1 and the second current i2 is greater than or equal to 6 milliamperes or less than 3 milliamperes, so it can be determined that there is a DC current difference between these paths Pi1 and Pi2 that is greater than or equal to 6 milliamperes or less than 3 milliamperes.

[0057] Conversely, the determination unit 22 provides the detection signal Sdet at a low level via the calculation unit 223 based on the net current signal being less than the current threshold. As described above, when the current value corresponding to the current threshold is zero amperes and the calculation unit 223 outputs the detection signal Sdet at a low level, it indicates that the net current value |i1-i2| between the first current i1 and the second current i2 is zero, and it can be determined that there is no DC or AC current difference between the paths Pi1 and Pi2. When the current value corresponding to the current threshold is 15 milliamperes and the calculation unit 223 outputs the detection signal Sdet at a low level, it indicates that the net current value |i1-i2| between the first current i1 and the second current i2 is less than 15 milliamperes, and it can be determined that there is no AC current difference of 15 milliamperes or more between the paths Pi1 and Pi2. If the current value corresponding to the current threshold is 3 to 6 milliamperes and the calculation unit 223 outputs a low-level detection signal Sdet, it indicates that the net current value |i1-i2| of the first current i1 and the second current i2 is less than 6 milliamperes or exceeds 3 milliamperes, so it can be determined that there is no DC current difference of more than 6 milliamperes or less than 3 milliamperes between these paths Pi1 and Pi2.

[0058] However, the present invention is not limited to determining that the net current value |i1-i2| is greater than or equal to the current threshold value when the detection signal Sdet is at a high level, and determining that the net current value |i1-i2| is less than the current threshold value when the detection signal Sdet is at a low level. In other words, the relationship between the net current value |i1-i2| and the current threshold value can be determined by inverting the signal levels. For example, if the current threshold is set to zero amperes and the calculation unit 223 outputs a low-level detection signal Sdet, it indicates that the net current value |i1-i2| of the first current i1 and the second current i2 is not zero. Conversely, if the calculation unit 223 outputs a high-level detection signal Sdet, it indicates that the net current value |i1-i2| of the first current i1 and the second current i2 is zero.

[0059] FIG. 9 is a schematic diagram of a second embodiment of a multi-path current difference detection device according to the present invention, implemented as an integrated circuit. As described above, the current difference detection device 200 can be implemented as a packaged integrated circuit. In FIG. 9, the current difference detection device 200 is an integrated circuit for multi-path current difference detection. The current difference detection device 200 is provided in contact with a first path Pi1 and a second path Pi2, both of which are traces on a bus (also called a bus bar, bus board, or bus bar) or a printed circuit board (PCB). Specifically, the terminals of the integrated circuit of the current difference detection device 200 are directly electrically connected to the first path Pi1 and the second path Pi2, thereby receiving the first current i1 and the second current i2 via the terminals of the integrated circuit. The sensing element 21 and the determination unit 22 provided in the integrated circuit receive the current, calculate the net current, determine the net current signal and the current threshold, and output the detection signal Sdet, thereby realizing contact detection of the multi-path current difference, but this will not be repeated here. As shown in Figure 9, the current difference detection device 200 can output the detection signal Sdet as an output voltage Vout via the output terminal Out. Furthermore, the current difference detection device 200 can be supplied with the necessary power from an external power supply voltage Vcc.

[0060] In summary, the present invention has the following features and advantages:

[0061] 1. The current difference detection device of the present invention can be realized as a packaged integrated circuit, thereby significantly reducing the volume and space it occupies.

[0062] 2. The current difference detection device of the present invention can realize non-contact or contact detection of multi-path current differences.

[0063] 3. The current difference detection device of the present invention can be used to detect AC or DC current.

[0064] 4. In preferred embodiments, it is possible to accurately detect AC current differences of 15 milliamps or more, or DC current differences of 6 milliamps or more and 3 milliamps or less.

[0065] 5. Different current path pitch design can avoid electromagnetic interference.

[0066] 6. The detection time for current difference detection according to the present invention can be reduced to less than one second.

[0067] 7. The detection accuracy of the current difference detection according to the present invention is higher than 95% (ie, the error is less than 5%).

[0068] 8. The current difference detection device of the present invention can operate in an environment higher than 150°C.

[0069] 9. In the present invention, the pitch of the laminates in the circuit board can be 0.4±0.1 mm.

[0070] The above is merely a detailed description and illustration of preferred specific embodiments of the present invention, and the features of the present invention are not limited thereto. The full scope of the present invention should be determined based on the following claims. Any embodiment that conforms to the spirit of the claims of this application is encompassed within the scope of this application, and any variations or modifications that can be easily thought up by a person skilled in the art should also be considered to be encompassed within the scope of the claims of this application. [Explanation of symbols]

[0071] 100: Current difference detector 11: Sensing element 12: Judgment unit Pi1: Pathway 1 Pi2: Second Pathway i1: First current i2: Second current Sin: Current signal Sdet: detection signal 121: Signal amplifier 122: Voltage Follower 200: Current difference detector 21: Sensing element 22: Judgment unit Sin1: First current signal Sin2: Second current signal 221-1: First signal amplifier 221-2: Second signal amplifier 222-1: First Voltage Follower 222-2: Second Voltage Follower 223: Computational unit L1~L6: 1st laminate to 6th laminate

Claims

1. a sensing element that senses a plurality of currents flowing through a plurality of paths and calculates a net current value of the plurality of current values; a determining unit for receiving a current signal corresponding to the net current value, determining that the current signal is equal to or greater than a current threshold, and providing a detection signal; A multi-path current difference detection device comprising:

2. The determination unit a signal amplifier that receives and amplifies the current signal; a voltage follower connected to the signal amplifier and receiving the amplified current signal; Including, The voltage follower providing the detection signal at a high level based on the amplified current signal being equal to or greater than the current threshold; The multi-path current difference detection device of claim 1 , wherein the detection signal is provided at a low level based on the amplified current signal being less than the current threshold.

3. 2. The multi-path current difference detection apparatus of claim 1, wherein the current value corresponding to the current threshold is zero amperes.

4. 3. The multi-path current differential detection device of claim 2, wherein the signal amplifier is an operational amplifier.

5. a sensing element for receiving a plurality of currents flowing through a plurality of paths; a determining unit that receives a plurality of current signals corresponding to a plurality of current values of the current, calculates a net current of the current values, determines that the net current signal corresponding to the net current is equal to or greater than a current threshold, and provides a detection signal; A multi-path current difference detection device comprising:

6. The determination unit a plurality of signal amplifiers each receiving and amplifying the current signal; a plurality of voltage followers connected to the signal amplifiers and receiving the amplified current signals, respectively; a calculation unit connected to the voltage followers, the calculation unit receiving each of the amplified current signals and summing the current signals to generate the net current signal corresponding to the net current; Including, The computing unit providing the detection signal at a high level based on the net current signal being greater than or equal to the current threshold; The multi-path current difference detection apparatus of claim 5 , wherein the detection signal is provided at a low level based on the net current signal being less than the current threshold.

7. 10. The multi-path current difference detection device according to claim 1, wherein the multi-path current difference detection device is an integrated circuit.

8. 6. The multi-path current difference detection device according to claim 1, wherein the current value corresponding to the current threshold is zero amperes.

9. 6. The multi-path current difference detection device according to claim 1, wherein each of the currents is an alternating current, and the current value corresponding to the current threshold is 15 milliamperes.

10. 10. The multi-path current difference detection device according to claim 1, wherein each of the currents is an AC current or a DC current, and the current value corresponding to the current threshold is 3 to 6 milliamperes DC.

11. 10. The multi-path current difference detection device according to claim 1, wherein the sensing element is a Hall element, a tunnel magnetoresistance, an anisotropic magnetoresistance, a giant magnetoresistance, a colossal magnetoresistance, a normal magnetoresistance, or a shunt resistor.

12. 7. The multi-path current differential sensing apparatus of claim 6, wherein each said signal amplifier is an operational amplifier.

13. The multi-path current difference detection device is provided on a circuit board that is a plurality of laminates having a stacked structure, 6. The multi-path current difference detection device of claim 1, wherein the paths are disposed on different laminates.

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