Multi-path current difference detection apparatus

Abstract

A multi-path current difference detection apparatus (100), comprising a sensing element (11) and a determination unit (12). The sensing element (11) senses a plurality of currents (i1, i2) flowing through a plurality of paths (Pi1, Pi2), and calculates a net current value (|i1 - i2|) for a plurality of current values of the currents (i1, 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 greater than or equal to a current threshold, and provides a detection signal (Sdet).

Description

Multi-path current difference detection device Technical Field

[0001] The present invention relates to a current difference detection device, and in particular to a multi-path current difference detection device. Background Art

[0002] Currently, current transformers (CTs) are commonly used to detect the different current directions in two or more paths. However, CTs are bulky, have complex circuitry, and are expensive. Furthermore, CTs are susceptible to temperature fluctuations and can cause accuracy drift when used to detect current. Therefore, in addition to CTs, Hall effect sensors are also used for current detection. However, a single Hall effect sensor can only detect current in a single path. Therefore, if you want to detect the different current directions in two or more paths, you must use more Hall effect sensors, which increases costs.

[0003] Therefore, how to design a multi-path current difference detection device to solve the problems and technical bottlenecks in the prior art is an important topic studied by the inventors of the present disclosure.

[0004] Summary of the Invention

[0005] One 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. The determination unit receives a current signal corresponding to the net current value, determines whether the current signal is greater than or equal to a current threshold, and provides a detection signal.

[0006] In one embodiment, the determination unit includes a signal amplifier and a voltage follower. The signal amplifier receives and amplifies a current signal. The voltage follower is connected to the signal amplifier and receives the amplified current signal. If the amplified current signal is greater than or equal to a current threshold, the voltage follower provides a high-level detection signal. If the amplified current signal is less than the current threshold, the voltage follower provides a low-level detection signal.

[0007] In one embodiment, the current difference detection device is an integrated circuit.

[0008] In one embodiment, the current threshold corresponds to a current value of zero ampere.

[0009] In one embodiment, each current is an alternating current, and the current value corresponding to the current threshold is 15 mA.

[0010] In one embodiment, each current is an AC or DC current, and the current value corresponding to the current threshold is 6 mA DC.

[0011] In one embodiment, the sensing element is a Hall element, a tunneling magnetoresistance, an anisotropic magnetoresistance, a giant magnetoresistance, an ultra-giant magnetoresistance, a constant magnetoresistance, or a shunt resistor.

[0012] In one embodiment, the signal amplifier is an operational amplifier.

[0013] In one embodiment, the current difference detection device is disposed on a circuit board, and the circuit board is a multi-layer board with a stacked structure, and the paths are respectively configured on different layers of the boards.

[0014] 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 the multiple current values ​​of the currents, calculates a net current of the current values, determines whether the net current signal corresponding to the net current is greater than or equal to a current threshold, and provides a detection signal.

[0015] 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 unit is connected to the voltage followers, receives the amplified current signals, and sums the current signals to generate a net current signal corresponding to the net current. If the net current signal is greater than or equal to a current threshold, the calculation unit provides a high-level detection signal. If the net current signal is less than the current threshold, the calculation unit provides a low-level detection signal.

[0016] In one embodiment, the current difference detection device is an integrated circuit.

[0017] In one embodiment, the current threshold corresponds to a current value of zero ampere.

[0018] In one embodiment, each current is an alternating current, and the current value corresponding to the current threshold is 15 mA.

[0019] In one embodiment, each current is an AC or DC current, and the current value corresponding to the current threshold is 6 mA DC.

[0020] In one embodiment, the sensing element is a Hall element, a tunneling magnetoresistance, an anisotropic magnetoresistance, a giant magnetoresistance, an ultra-giant magnetoresistance, a constant magnetoresistance, or a shunt resistor.

[0021] In one embodiment, the signal amplifier is an operational amplifier.

[0022] In one embodiment, the current difference detection device is disposed on a circuit board, and the circuit board is a multi-layer board with a stacked structure, and the paths are respectively configured on different layers of the boards.

[0023] Thus, the multi-path current difference detection device proposed in the present invention has the following features and advantages: 1. The current difference detection device of the present invention can be implemented as a packaged integrated circuit, thereby significantly reducing the volume and space occupied by it; 2. The current difference detection device of the present invention can implement multi-path current difference detection in a non-contact manner or a contact manner; 3. The current difference detection device of the present invention can be used to detect AC current or DC current; 4. In a preferred embodiment, an AC current difference of more than 15 mA or a DC current difference of more than 6 mA can be accurately detected; 5. Electromagnetic interference can be avoided by designing the distance between different current paths; 6. The detection time of the current difference detection of the present invention can be less than 1 second; 7. The detection accuracy of the current difference detection of the present invention is greater 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 above 150°C; 9. The distance between the multiple layers of the laminated structure of the circuit board of the present invention can be designed to be 0.4±0.1 mm.

[0024] In order to further understand the techniques, means and technical effects adopted by the present invention to achieve the intended purpose, please refer to the following detailed description and drawings of the present invention. It is believed that the purpose, characteristics and features of the present invention can be understood in depth and in detail. However, the drawings in the specification are provided for reference and illustration only and are not intended to limit the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] FIG1 is a schematic diagram of a conventional current transformer for detecting current.

[0026] FIG2 is a block diagram of a first embodiment of a multi-path current difference detection device according to the present invention.

[0027] FIG3 is a circuit block diagram of a first embodiment of a multi-path current difference detection device according to the present invention.

[0028] FIG4 is a first schematic diagram showing a first embodiment of the multi-path current difference detection device of the present invention implemented as an integrated circuit.

[0029] FIG5 is a second schematic diagram showing the first embodiment of the multi-path current difference detection device of the present invention implemented as an integrated circuit.

[0030] 6A to 6C are schematic diagrams of the multi-path current difference detection device of the present invention applied to a laminated circuit board.

[0031] FIG7 is a block diagram of a second embodiment of a multi-path current difference detection device according to the present invention.

[0032] FIG8 is a circuit block diagram of a second embodiment of a multi-path current difference detection device according to the present invention.

[0033] FIG9 is a schematic diagram showing a second embodiment of the multi-path current difference detection device of the present invention implemented as an integrated circuit.

[0034] Explanation of the reference numerals: 100: current difference detection device 11: sensing element 12: judgment unit Pi1: first path Pi2: second path i1: first current i2: second current Sin: current signal Sdet: detection signal 121: signal amplifier 122: voltage follower 200: current difference detection device 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: calculation unit L1~L6: first to sixth layer boards DETAILED DESCRIPTION

[0035] The technical content and detailed description of the present invention are described as follows with reference to the accompanying drawings.

[0036] The following describes the implementation of the present invention through specific embodiments. Those skilled in the art will readily understand the other advantages and technical effects of the present invention from the disclosure herein. The present invention may also be implemented or applied through other specific embodiments, and the details in this specification may be modified and altered based on different viewpoints and applications without departing from the spirit of the present invention.

[0037] It should be noted that the structures, proportions, sizes, number of components, etc. shown in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions under which the present invention can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should fall within the scope of the technical content disclosed in the present invention without affecting the technical effects and purposes that can be achieved by the present invention.

[0038] Please refer to Figure 2, which is a block diagram of a first embodiment of a multi-path current difference detection device according to the present invention. As shown in Figure 2, the multi-path means multiple paths through which current can flow, and the current flow direction along each path is not restricted.

[0039] The multi-path current difference detection device 100 of the first embodiment shown in FIG2 includes sensing elements 11 and a determination unit 12. Each sensing element 11 senses current to generate a magnetic field. Thus, the magnitude of the sensed current and the corresponding magnetic field change can generate an electrical signal (for example, but not limited to, a voltage signal). Therefore, the magnitude of the electrical signal can be used to determine the magnitude of all currents sensed on the multiple paths, or the net current magnitude. In the present invention, each sensing element 11 is a Hall element, a tunnel magnetoresistance (TMR), anisotropic magnetoresistance (AMR), giant magnetoresistance (GMR), colossal magnetoresistance (CMR), ordinary magnetoresistance (OMR), or a shunt resistor. However, the present invention is not limited to these elements. Any element that can achieve the aforementioned functions and purposes can be used as the sensing element 11 and should fall within the scope of the technical content disclosed in the present invention.

[0040] It is worth mentioning that the current difference detection device 100 is an integrated circuit (IC), which means that the current difference detection device 100 can be implemented as a packaged integrated circuit, thereby significantly reducing the volume and space occupied by the current difference detection device 100 .

[0041] Sensing element 11 is used to sense multiple currents i1 and i2 flowing through multiple paths Pi1 and Pi2. As shown in FIG2 , two paths, namely, first path Pi1 and second path Pi2, are used as an example. Therefore, sensing element 11 can be used to sense the magnitude of first current i1 flowing through first path Pi1 and the magnitude of second current i2 flowing through second path Pi2. In the present invention, sensing element 11 can also be used to sense the magnitude of currents in more than two paths, which will not be discussed further here. Based on the magnitude of first current i1 and second current i2, sensing element 11 calculates the net current value |i1-i2| of the multiple current values ​​of these currents i1 and i2. In other words, the net current calculated by sensing element 11 is |i1-i2| or |i2-i1|, indicating that the net current value only considers the magnitude of the net current and does not consider the direction of the first current i1 and the second current i2. Incidentally, if the net current of three currents is calculated, the net current is |i1-i2-i3| or the absolute value of the difference between the three currents.

[0042] The judgment unit 12 is connected to the sensing element 11 and receives a current signal Sin corresponding to the net current value |i1-i2|. It determines whether the current signal Sin is greater than or equal to a current threshold and provides a detection signal Sdet. Specifically, the net current value |i1-i2| is the actual current value, so the sensing element 11 converts the actual current value into the corresponding current signal Sin. In other words, a larger current signal Sin indicates a larger net current value |i1-i2|, and conversely, a smaller current signal Sin indicates a smaller 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 greater than or equal to the current threshold, it provides a detection signal Sdet.

[0043] Incidentally, the sensing element 11 can be used to sense AC or DC current. Therefore, in one embodiment, the current threshold corresponds to a current value of zero amperes. That is, when the current signal Sin is greater than or equal to zero amperes (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 non-zero. Therefore, it can be determined that a non-zero DC or AC current difference exists between the paths Pi1 and Pi2.

[0044] In another embodiment, if the first current i1 and the second current i2 are AC currents, and the current value corresponding to the current threshold is 15 mA, then when the current signal Sin is greater than or equal to 15 mA (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 or equal to 15 mA. Therefore, it can be determined that an AC current difference greater than or equal to 15 mA exists between the paths Pi1 and Pi2.

[0045] Similarly, in another embodiment, if the first current i1 and the second current i2 are AC or DC currents, and the current value corresponding to the current threshold is 6 mA DC, then when the current signal Sin is greater than or equal to 6 mA (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 or equal to 6 mA. Therefore, it can be determined that a DC current difference greater than or equal to 6 mA exists between the paths Pi1 and Pi2.

[0046] Please refer to FIG3 , which is a circuit block diagram of a first embodiment of a multi-path current difference detection device according to the present invention. FIG3 further discloses and illustrates an implementation of the judgment unit 12. As shown in FIG3 , the judgment 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 the current signal Sin to generate a corresponding voltage signal by operating as an operational amplifier. The voltage follower 122 is connected to the signal amplifier 121 and receives the amplified current signal Sin, that is, receives the voltage signal generated by the signal amplifier 121.

[0047] The determination unit 12 provides a high-level detection signal Sdet from the voltage follower 122 based on the amplified current signal Sin being greater than or equal to the current threshold. Corresponding to the aforementioned description, if the current value corresponding to the current threshold is zero amperes and the voltage follower 122 outputs a high-level detection signal Sdet, this indicates that the net current value |i1-i2| between the first current i1 and the second current i2 is non-zero, thereby determining that a non-zero DC or AC current difference exists between the paths Pi1 and Pi2. If the current value corresponding to the current threshold is 15 milliamperes and the voltage follower 122 outputs a high-level detection signal Sdet, this indicates that the net current value |i1-i2| between the first current i1 and the second current i2 is greater than or equal to 15 milliamperes, thereby determining that an AC current difference greater than or equal to 15 milliamperes exists between the paths Pi1 and Pi2. If the current value corresponding to the current threshold is 6 mA and the voltage follower 122 outputs a high-level detection signal Sdet, it means that the net current value |i1-i2| of the first current i1 and the second current i2 is greater than or equal to 6 mA. Therefore, it can be determined that a DC current difference greater than or equal to 6 mA exists between the paths Pi1 and Pi2.

[0048] Conversely, the determination unit 12 provides a low-level detection signal Sdet from the voltage follower 122 based on the amplified current signal Sin being less than the current threshold. Corresponding to the aforementioned description, if the current value corresponding to the current threshold is zero amperes and the voltage follower 122 outputs a low-level detection signal Sdet, this indicates that the net current value |i1-i2| between the first current i1 and the second current i2 is zero, thus determining that no DC or AC current difference exists between the paths Pi1 and Pi2. If the current value corresponding to the current threshold is 15 milliamperes and the voltage follower 122 outputs a low-level detection signal Sdet, this indicates that the net current value |i1-i2| between the first current i1 and the second current i2 is less than 15 milliamperes, thus determining that no AC current difference greater than or equal to 15 milliamperes exists between the paths Pi1 and Pi2. If the current value corresponding to the current threshold is 6 mA and the voltage follower 122 outputs a low-level detection signal Sdet, it means that the net current value |i1-i2| of the first current i1 and the second current i2 is less than 6 mA. Therefore, it can be determined that there is no DC current difference greater than or equal to 6 mA between the paths Pi1 and Pi2.

[0049] However, the above-mentioned high-level detection signal Sdet is not used to determine whether the net current value |i1-i2| is greater than or equal to the current threshold, and the low-level detection signal Sdet is not used to determine whether the net current value |i1-i2| is less than the current threshold. In other words, the relationship between the net current value |i1-i2| and the current threshold can also be determined using the opposite signal level. For example, if the current threshold is set to zero amperes and the voltage follower 122 outputs a low-level detection signal Sdet, it can 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 can indicate that the net current value |i1-i2| of the first current i1 and the second current i2 is zero.

[0050] Please refer to Figure 4, which is a schematic diagram of a first embodiment of a multi-path current difference detection device according to the present invention implemented as an integrated circuit. As previously mentioned, the current difference detection device 100 can be implemented as a packaged integrated circuit. Therefore, in Figure 4, the current difference detection device 100 is an integrated circuit for multi-path current difference detection. The current difference detection device 100 is configured in a contactless manner on a first path Pi1 and a second path Pi2. The first path Pi1 and the second path Pi2 can be traces of a bus (also known as a bus bar) or a printed circuit board (PCB). Figure 4 uses a bus as an example, so the bottom view (top view) of Figure 4 shows the current difference detection device 100 configured in a contactless manner on 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 i1, i2 flowing through the second path Pi2 are sensed by a sensing element 11. Furthermore, the sensing element 11 calculates the net current value |i1-i2| of the first current i1 and the second current i2. The determination unit 12 then receives the current signal Sin corresponding to the net current value |i1-i2|, determines whether the current signal Sin is greater than or equal to a current threshold, and provides a detection signal Sdet. As shown in FIG4 , the current difference detection device 100 can output the detection signal Sdet as an output voltage Vout via an output pin Out. Furthermore, the current difference detection device 100 can be powered by an externally provided power supply voltage Vcc.

[0051] Please refer to Figure 5, which is a second schematic diagram of the first embodiment of the multi-path current difference detection device of the present invention implemented as an integrated circuit. As shown in Figure 5, a bus is used as an example. Therefore, the bottom view (top view) shown in Figure 5 shows the current difference detection device 100 disposed in a non-contact manner on the first path Pi1 and the second path Pi2 of the bus. A sensing element 11 senses a first current i1 flowing through the first path Pi1 and a second current i1, i2 flowing through the second path Pi2. Furthermore, the sensing element 11 calculates the net current value |i1-i2| of the first current i1 and the second current i2. The determination unit 12 then receives a current signal Sin corresponding to the net current value |i1-i2| and determines whether the current signal Sin is greater than or equal to a current threshold, providing a detection signal Sdet. As shown in Figure 5, the current difference detection device 100 can output the detection signal Sdet as an output voltage Vout via an output pin Out. Furthermore, the current difference detection device 100 can be powered by an externally provided power supply voltage Vcc.

[0052] Please refer to Figures 6A to 6C, which are schematic diagrams of the multi-path current difference detection device of the present invention applied to a laminated circuit board. Incidentally, the content shown in Figures 6A to 6C is primarily for the purpose of clearly and conveniently presenting the schematic diagram of the current difference detection device 100 applied to a laminated circuit board, so this description will be omitted. The current difference detection device 100 is disposed on a circuit board, which is a multi-layer board with a laminated structure, wherein the paths Pi1 and Pi2 are respectively configured on different layers. As shown in Figure 6A, the circuit board has two layers, namely a first layer L1 and a second layer L2, with the first path Pi1 configured on the first layer L1 and the second path Pi2 configured on the second layer L2. The current difference detection device 100 is non-contactly disposed on the first path Pi1 and the second path Pi2 and is electrically connected to the first layer L1 of the circuit board. Therefore, through the aforementioned technical means, multi-path current difference detection is achieved using the sensing element 11 and the judgment unit 12, and no further details will be given here.

[0053] As shown in Figure 6B , the circuit board has four layers: a first layer L1, a second layer L2, a third layer L3, and a fourth layer L4. The first path Pi1 is located on the second layer L2, and the second path Pi2 is located on the third layer L3. However, this is not limiting, and neither the number of paths nor the layer positions on which they are located are limited. The current difference detection device 100 is non-contactly disposed on the first path Pi1 and the second path Pi2 and electrically connected to the first layer L1 of the circuit board. Therefore, through the aforementioned technical means, the sensing element 11 and the determination unit 12 implement multi-path current difference detection, which will not be elaborated upon here.

[0054] As shown in FIG6C , the circuit board has six layers: a first layer L1, a second layer L2, a third layer L3, a fourth layer L4, a fifth layer L5, and a sixth layer L6. A first path Pi1 is disposed on the second layer L2, a second path Pi2 is disposed on the third layer L3, a third path Pi3 is disposed on the fourth layer L4, and a fourth path Pi4 is disposed on the fifth layer L5. However, this is not limiting, and the number of paths and the layer positions on which they are disposed are not limited. The current difference detection device 100 is non-contactly disposed 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 layer L1 of the circuit board. Therefore, through the aforementioned technical means, multi-path current difference detection is achieved using the sensing element 11 and the determination unit 12, which will not be elaborated upon here.

[0055] Please refer to FIG7 , which 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 according to the second embodiment shown in FIG7 includes a sensing element 21 and a determination unit 22 . Compared to the non-contact detection method of the first embodiment shown in FIG2 , the current difference detection device 200 according to this embodiment uses a contact detection method. Therefore, the sensing element 21 is used to directly sense the current magnitude in a contact manner. In the present invention, each sensing element 21 is 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 the present invention is not limited to these elements.

[0056] It is worth mentioning that the current difference detection device 200 is an integrated circuit (IC), which means that the current difference detection device can be implemented as a packaged integrated circuit, thereby significantly reducing the volume and space occupied by the current difference detection device.

[0057] Sensing element 21 receives multiple currents i1 and i2 flowing through multiple paths Pi1 and Pi2. For example, using the two paths shown in FIG7 , sensing element 21 receives the magnitude of a first current i1 flowing through a first path Pi1 and the magnitude of a second current i2 flowing through a second path Pi2. In the present invention, sensing element 21 can also be used to receive the magnitude of currents in more than two paths, which will not be elaborated upon here.

[0058] The judgment unit 22 is connected to the sensing element 21 and receives complex current signals Sin1 and Sin2 corresponding to the complex current values ​​of the corresponding currents i1 and i2. In other words, the judgment unit 22 receives a first current signal Sin1 corresponding to the current value of the first current i1 and a second current signal Sin2 corresponding to the current value of the second current i2. Furthermore, the judgment 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. In other words, the net current calculated by the judgment unit 22 is |i1-i2| or |i2-i1|, indicating that the net current value only considers the magnitude of the net current value and does not consider the flow direction of the first current i1 and the second current i2.

[0059] The determination unit 22 determines whether a net current signal corresponding to the net current |i1-i2| is greater than or equal to a 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., a larger first current signal Sin1 indicates a larger first current i1, and vice versa). It also converts the actual current value of the second current i2 into a corresponding second current signal Sin2 (i.e., a larger second current signal Sin2 indicates a larger second current i2, and vice versa), and provides these signals to the determination unit 22. Therefore, the determination unit 22 calculates the net current of the first current i1 and the second current i2 based on the first current signal Sin1 and the second current signal Sin2. Therefore, the determination unit 12 receives the current threshold and compares the net current signal corresponding to the net current |i1-i2| with the current threshold. If the determination unit 12 determines that the net current signal is greater than or equal to the current threshold, it provides a detection signal Sdet.

[0060] Incidentally, the sensing element 21 can be used to sense AC or DC current. Therefore, in one embodiment, the current threshold corresponds to a current value of zero amperes. That is, when the net current signal is greater than or equal to 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 non-zero. Therefore, it can be determined that a non-zero DC or AC current difference exists between the paths Pi1 and Pi2.

[0061] In another embodiment, if the first current i1 and the second current i2 are AC currents, and the current value corresponding to the current threshold is 15 mA, then when the net current signal is greater than or equal to 15 mA (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 or equal to 15 mA. Therefore, it can be determined that an AC current difference greater than or equal to 15 mA exists between the paths Pi1 and Pi2.

[0062] Similarly, in another embodiment, if the first current i1 and the second current i2 are AC or DC currents, and the current value corresponding to the current threshold is 6 mA DC, then when the net current signal is greater than or equal to 6 mA (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 or equal to 6 mA. Therefore, it can be determined that a DC current difference greater than or equal to 6 mA exists between the paths Pi1 and Pi2.

[0063] Please refer to FIG8 , which is a circuit block diagram of a second embodiment of a multi-path current difference detection device according to the present invention. FIG8 further discloses and illustrates an implementation of the determination unit 22 . As shown in FIG8 , the determination unit 22 includes complex signal amplifiers 221 - 1 , 221 - 2 , complex voltage followers 222 - 1 , 222 - 2 , and a calculation unit 223 . The complex signal amplifiers 221 - 1 , 221 - 2 respectively receive the current signals Sin1 , Sin2 , and amplify the current signals Sin1 , Sin2 , respectively. In one embodiment, each of the signal amplifiers is an operational amplifier (OPA). Therefore, the first signal amplifier 221 - 1 receives the first current signal Sin1 and amplifies the first current signal Sin1 as an operational amplifier; the second signal amplifier 221 - 2 receives the second current signal Sin2 and amplifies the second current signal Sin2 as an operational amplifier.

[0064] The plurality of voltage followers 222-1, 222-2 are connected to the signal amplifiers 221-1, 221-2, respectively, 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; the second voltage follower 222-2 is connected to the second signal amplifier 221-2 and receives the amplified second current signal Sin2.

[0065] The calculation unit 223 is connected to the voltage followers 222-1 and 222-2, receives the amplified current signals Sin1 and Sin2, respectively, and sums 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, respectively, and further sums the amplified first current signal Sin1 and the amplified second current signal Sin2 to generate a net current signal corresponding to the net current |i1-i2|.

[0066] Based on the net current signal being greater than or equal to the current threshold, the determination unit 22 generates a high-level detection signal Sdet from the calculation unit 223. As previously described, if the current value corresponding to the current threshold is zero amperes and the calculation unit 223 outputs a high-level detection signal Sdet, this indicates that the net current value |i1-i2| between the first current i1 and the second current i2 is non-zero, thereby determining that a non-zero DC or AC current difference exists between the paths Pi1 and Pi2. If the current value corresponding to the current threshold is 15 milliamperes and the calculation unit 223 outputs a high-level detection signal Sdet, this indicates that the net current value |i1-i2| between the first current i1 and the second current i2 is greater than or equal to 15 milliamperes, thereby determining that an AC current difference exists between the paths Pi1 and Pi2 is greater than or equal to 15 milliamperes. If the current value corresponding to the current threshold is 6 mA and the calculation unit 223 outputs a high-level detection signal Sdet, it means that the net current value |i1-i2| of the first current i1 and the second current i2 is greater than or equal to 6 mA. Therefore, it can be determined that a DC current difference greater than or equal to 6 mA exists between the paths Pi1 and Pi2.

[0067] Conversely, if the net current signal is less than the current threshold, the calculation unit 223 provides a low-level detection signal Sdet. Corresponding to the aforementioned description, if the current value corresponding to the current threshold is zero amperes and the calculation unit 223 outputs a low-level detection signal Sdet, this indicates that the net current value |i1-i2| between the first current i1 and the second current i2 is zero, thus determining that no DC or AC current difference exists between the paths Pi1 and Pi2. If the current value corresponding to the current threshold is 15 milliamperes and the calculation unit 223 outputs a low-level detection signal Sdet, this indicates that the net current value |i1-i2| between the first current i1 and the second current i2 is less than 15 milliamperes, thus determining that no AC current difference greater than or equal to 15 milliamperes exists between the paths Pi1 and Pi2. If the current value corresponding to the current threshold is 6 mA and the calculation unit 223 outputs a low-level detection signal Sdet, it means that the net current value |i1-i2| of the first current i1 and the second current i2 is less than 6 mA. Therefore, it can be determined that there is no DC current difference greater than or equal to 6 mA between the paths Pi1 and Pi2.

[0068] However, the above-mentioned high-level detection signal Sdet is not used to determine whether the net current value |i1-i2| is greater than or equal to the current threshold, and the low-level detection signal Sdet is not used to determine whether the net current value |i1-i2| is less than the current threshold. In other words, the relationship between the net current value |i1-i2| and the current threshold can also be determined using the opposite signal level. For example, if the current threshold is set to zero amperes and the calculation unit 223 outputs a low-level detection signal Sdet, it can indicate that the net current value |i1-i2| representing 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 can indicate that the net current value |i1-i2| representing the first current i1 and the second current i2 is zero.

[0069] Please refer to FIG9 , which 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 previously mentioned, the current difference detection device 200 can be implemented as a packaged integrated circuit. Therefore, in FIG9 , 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 a contact manner on the first path Pi1 and the second path Pi2, where the first path Pi1 and the second path Pi2 can be bus bars or traces on a printed circuit board (PCB). Specifically, the pins of the integrated circuit serving as 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 pins of the integrated circuit. The sensing element 21 and the determination unit 22 provided within the integrated circuit then perform current reception, calculate the net current, determine the net current signal and the current threshold, and output the detection signal Sdet, thereby implementing multi-path current difference detection in a contact manner. This will not be described in detail here. 9 , the current difference detection device 200 can output the detection signal Sdet as an output voltage Vout via an output pin Out. Furthermore, the current difference detection device 200 can be powered by an externally provided power supply voltage Vcc.

[0070] In summary, the present invention has the following features and advantages:

[0071] 1. The current difference detection device of the present invention can be implemented as a packaged integrated circuit, thereby significantly reducing the volume and space occupied by the device.

[0072] 2. The current difference detection device of the present invention can realize multi-path current difference detection in a non-contact manner or a contact manner.

[0073] 3. The current difference detection device of the present invention can be used to detect alternating current or direct current.

[0074] 4. In a preferred embodiment, an AC current difference of 15 mA or more can be accurately detected, or a DC current difference of 6 mA or more can be accurately detected.

[0075] 5. Electromagnetic interference can be avoided by designing the spacing between different current paths.

[0076] 6. The detection time of the current difference detection of the present invention can be less than 1 second.

[0077] 7. The detection accuracy of the current difference detection of the present invention is higher than 95% (ie the error is lower than 5%).

[0078] 8. The current difference detection device of the present invention can operate in an environment above 150°C.

[0079] 9. The spacing between the multiple layers of the laminated structure of the circuit board of the present invention can be designed to be 0.4±0.1 mm.

[0080] The above description is only a detailed description and drawings of preferred specific embodiments of the present invention, and the features of the present invention are not limited thereto and are not intended to limit the present invention. The full scope of the present invention shall be based on the following claims. All embodiments that are consistent with the concepts of the claims of the present invention and similar variations thereof shall be included in the scope of the present invention. Any changes or modifications that can be easily conceived by any person skilled in the art within the field of the present invention shall be covered by the claims of this disclosure.

Claims

1. A multi-path current difference detection device, comprising: a sensing element for sensing the plurality of currents flowing through the plurality of paths and calculating a net current value of the plurality of current values; as well as A determination unit receives a current signal corresponding to the net current value, determines whether the current signal is greater than or equal to a current threshold, and provides a detection signal.

2. The current difference detection device according to claim 1 , wherein the judgment unit comprises: a signal amplifier, receiving the current signal and amplifying the current signal; as well as a voltage follower connected to the signal amplifier and receiving the amplified current signal; Wherein, based on the amplified current signal being greater than or equal to the current threshold, the voltage follower provides the detection signal of a high level; When the amplified current signal is smaller than the current threshold, the voltage follower provides the detection signal of a low level. 3 . The current difference detection device as claimed in claim 1 , wherein the current difference detection device is an integrated circuit. The current difference detection device as claimed in claim 1 , wherein the current value corresponding to the current threshold is zero ampere. 5 . The current difference detection device as claimed in claim 1 , wherein each of the currents is an alternating current, and the current value corresponding to the current threshold is 15 mA. 6 . The current difference detection device as claimed in claim 1 , wherein each of the currents is an alternating current or a direct current, and the current value corresponding to the current threshold is 6 mA DC. 7 . The current difference detection device as claimed in claim 1 , wherein the sensing element is a Hall element, a tunneling magnetoresistor, an anisotropic magnetoresistor, a giant magnetoresistor, an ultra-giant magnetoresistor, a normal magnetoresistor, or a shunt resistor. 8 . The current difference detection device as claimed in claim 2 , wherein the signal amplifier is an operational amplifier.

9. The current difference detection device as claimed in claim 1, wherein the current difference detection device is disposed on a circuit board, and the circuit board is a multi-layer board having a laminated structure; The plurality of paths are respectively configured on different plurality of layers of boards.

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

11. The current difference detection device according to claim 10, wherein the judgment unit comprises: a complex signal amplifier, receiving the complex current signals respectively and amplifying the complex current signals respectively; a complex voltage follower, correspondingly connected to the complex signal amplifier and respectively receiving the amplified complex current signal; as well as a calculation unit connected to the plurality of voltage followers, receiving the amplified plurality of current signals respectively, and summing the plurality of current signals to generate a net current signal corresponding to the net current; Wherein, based on the net current signal being greater than or equal to the current threshold, the calculation unit provides the detection signal of a high level; When the net current signal is less than the current threshold, the calculation unit provides the detection signal of a low level. 12 . The current difference detection device as claimed in claim 10 , wherein the current difference detection device is an integrated circuit. 13 . The current difference detection device as claimed in claim 10 , wherein the current value corresponding to the current threshold is zero ampere. 14 . The current difference detection device as claimed in claim 10 , wherein each of the currents is an alternating current, and the current value corresponding to the current threshold is 15 mA. 15 . The current difference detection device as claimed in claim 10 , wherein each of the currents is an alternating current or a direct current, and the current value corresponding to the current threshold is 6 mA DC. 16 . The current difference detection device as claimed in claim 10 , wherein the sensing element is a Hall element, a tunneling magnetoresistor, an anisotropic magnetoresistor, a giant magnetoresistor, an ultra-giant magnetoresistor, a normal magnetoresistor, or a shunt resistor. 17 . The current difference detection device as claimed in claim 11 , wherein each of the signal amplifiers is an operational amplifier.

18. The current difference detection device as claimed in claim 10, wherein the current difference detection device is disposed on a circuit board, and the circuit board is a multi-layer board having a laminated structure; The plurality of paths are respectively configured on different plurality of layers of boards.

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