US20220137103A1 - Differential current sensor - Google Patents
Differential current sensor Download PDFInfo
- Publication number
- US20220137103A1 US20220137103A1 US17/083,487 US202017083487A US2022137103A1 US 20220137103 A1 US20220137103 A1 US 20220137103A1 US 202017083487 A US202017083487 A US 202017083487A US 2022137103 A1 US2022137103 A1 US 2022137103A1
- Authority
- US
- United States
- Prior art keywords
- current
- conductive trace
- integrated circuit
- current sensor
- magnetic field
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000005291 magnetic effect Effects 0.000 claims abstract description 80
- 238000000034 method Methods 0.000 claims abstract description 25
- 230000005355 Hall effect Effects 0.000 claims description 18
- 238000004364 calculation method Methods 0.000 claims description 15
- 230000035945 sensitivity Effects 0.000 claims description 9
- 239000004065 semiconductor Substances 0.000 claims description 7
- 230000005641 tunneling Effects 0.000 claims description 7
- 230000007704 transition Effects 0.000 claims 3
- 239000012212 insulator Substances 0.000 claims 2
- 239000004020 conductor Substances 0.000 description 30
- 230000006870 function Effects 0.000 description 9
- 238000004590 computer program Methods 0.000 description 7
- 239000000758 substrate Substances 0.000 description 6
- 230000005294 ferromagnetic effect Effects 0.000 description 3
- WPYVAWXEWQSOGY-UHFFFAOYSA-N indium antimonide Chemical compound [Sb]#[In] WPYVAWXEWQSOGY-UHFFFAOYSA-N 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- JBRZTFJDHDCESZ-UHFFFAOYSA-N AsGa Chemical compound [As]#[Ga] JBRZTFJDHDCESZ-UHFFFAOYSA-N 0.000 description 1
- 239000004593 Epoxy Substances 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- -1 e.g. Chemical compound 0.000 description 1
- 229910052732 germanium Inorganic materials 0.000 description 1
- GNPVGFCGXDBREM-UHFFFAOYSA-N germanium atom Chemical compound [Ge] GNPVGFCGXDBREM-UHFFFAOYSA-N 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 150000002472 indium compounds Chemical class 0.000 description 1
- 230000005381 magnetic domain Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/10—Measuring sum, difference or ratio
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/20—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using galvano-magnetic devices, e.g. Hall-effect devices, i.e. measuring a magnetic field via the interaction between a current and a magnetic field, e.g. magneto resistive or Hall effect devices
- G01R15/207—Constructional details independent of the type of device used
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/145—Indicating the presence of current or voltage
- G01R19/15—Indicating the presence of current
Definitions
- Some conventional current sensors are positioned near a current-carrying conductor to sense a magnetic field generated by a current through the conductor.
- the current sensor generates an output signal having a magnitude proportional to the magnetic field induced by the current through the conductor.
- Some current sensors such as a ground fault interrupt (GFI) current sensor, are configured to look for small differences in current, typically less than 0.01% of full scale or less than 25 mA, between two conductors. Having a current sensor which can effectively determine when a difference exits between two conductors can be challenging.
- GFI ground fault interrupt
- Example embodiments of the disclosure provide methods and apparatus for sensing a current between two or more conductors, or wires, such as a current sensor or a differential magnetic field sensor.
- a current sensor such as a current sensor or a differential magnetic field sensor.
- the difference of these two magnetic fields is compared to a threshold for providing an output to indicate a difference between the first and second currents above a predetermined level.
- the first and second conductors may be conductive traces on a printed circuit board or hybrid circuit.
- the current sensor may be positioned above the two conductive traces on the circuit board or hybrid circuit.
- the current sensor may contain one or more magnetic field sensing elements, which may comprise a planar Hall element, a vertical Hall element, or a magnetoresistance element, such as a giant magnetoresistance element (GMR), a tunneling magnetoresistance element (TMR) or a magnetic tunnel junction (MTJ), or a combination of magnetic field sensing elements.
- a magnetoresistance element such as a giant magnetoresistance element (GMR), a tunneling magnetoresistance element (TMR) or a magnetic tunnel junction (MTJ), or a combination of magnetic field sensing elements.
- GMR giant magnetoresistance element
- TMR tunneling magnetoresistance element
- MTJ magnetic tunnel junction
- the current sensor may contain a current calculation circuit on the integrated current sensor die to calculate the current flowing in the conductive traces, or wires, as the measured value of the magnetic field combination from the two wire, or positioned so that the current in each wire is measured independently.
- a disconnect output signal may be generated by the current calculation circuit and provided as an output of the current sensor integrated circuit.
- the output disconnect signal may be activated by a current difference between the two conductors of approximately 10%, 20%, or more.
- a current sensor or differential Hall sensor can be positioned near first and second conductive wires, or traces on printed circuit board or hybrid circuit, to compare the current in the two conductors by measuring the magnetic field generated by the two conductors, either as one measurement or a combination of measuring the two currents independently.
- An output disconnect signal from the current sensor or the differential Hall sensor can correspond to the current comparison.
- a method may use one or more magnetic field sensing elements to measure the current in the conductive traces.
- the magnetic field sensing elements may comprise a planar Hall element, a vertical Hall element, or a magnetoresistance element, such as a giant magnetoresistance element (GMR), a tunneling magnetoresistance element (TMR) or magnetic tunnel junction (MTJ), or a combination of magnetic field sensing elements.
- GMR giant magnetoresistance element
- TMR tunneling magnetoresistance element
- MTJ magnetic tunnel junction
- the method to provide a output disconnect signal from the current sensor or differential Hall sensor integrated circuit may contain a current calculation circuit on the integrated current sensor die to calculate the current flowing in the conductive traces, or wires as the measured value of the magnetic field combination from the two wire, or positioned so that the current in each wire is measured independently.
- a disconnect output signal may be generated by the current calculation circuit and provided as an output of the current sensor integrated circuit.
- the method may provide an output disconnect signal activated by a current difference between the two conductors of approximately 10%, 20%, or more. The method may be used to detect a ground or reference voltage disconnect in a motor.
- FIG. 1 shows a current sensor system with a current sensor IC package
- FIG. 2 Is a top view of a current sensor integrated circuit package mounted on a printed circuit board;
- FIG. 2A is a side of a current sensor integrated circuit package mounted on a printed circuit board
- FIG. 3 is a schematic overview of a circuit for use in the current sensor integrated circuit.
- FIG. 4 is a flow diagram of a method for determining a current difference between a plurality of conductors in the current sensor system.
- magnetic field sensing element is used to describe a variety of electronic elements that can sense a magnetic field.
- the magnetic field sensing element can be, but is not limited to, a Hall effect element, a magnetoresistance element, or a magnetotransistor.
- Hall effect elements for example, a planar Hall element, a vertical Hall element, and a Circular Vertical Hall (CVH) element.
- magnetoresistance elements for example, a semiconductor magnetoresistance element such as Indium Antimonide (InSb), a giant magnetoresistance (GMR) element, for example, a spin valve, an anisotropic magnetoresistance element (AMR), a tunneling magnetoresistance (TMR) element, and a magnetic tunnel junction (MTJ).
- the magnetic field sensing element may be a single element or, alternatively, may include two or more magnetic field sensing elements arranged in various configurations, e.g., a half-bridge or full (Wheatstone) bridge.
- the magnetic field sensing element may be a device made of a type IV semiconductor material such as Silicon (Si) or Germanium (Ge), or a type III-V semiconductor material like Gallium-Arsenide (GaAs) or an Indium compound, e.g., Indium-Antimonide (InSb).
- a type IV semiconductor material such as Silicon (Si) or Germanium (Ge)
- a type III-V semiconductor material like Gallium-Arsenide (GaAs) or an Indium compound, e.g., Indium-Antimonide (InSb).
- some of the above-described magnetic field sensing elements tend to have an axis of maximum sensitivity parallel to a substrate that supports the magnetic field sensing element, and others of the above-described magnetic field sensing elements tend to have an axis of maximum sensitivity perpendicular to a substrate that supports the magnetic field sensing element.
- planar Hall elements tend to have axes of sensitivity perpendicular to a substrate
- metal based or metallic magnetoresistance elements e.g., GMR, TMR, AMR
- vertical Hall elements tend to have axes of sensitivity parallel to a substrate.
- magnetic field sensor is used to describe a circuit that uses a magnetic field sensing element, generally in combination with other circuits.
- Magnetic field sensors are used in a variety of applications, including, but not limited to, an angle sensor that senses an angle of a direction of a magnetic field, a current sensor that senses a magnetic field generated by a current carried by a current-carrying conductor, a magnetic switch that senses the proximity of a ferromagnetic object, a rotation detector that senses passing ferromagnetic articles, for example, magnetic domains of a ring magnet or a ferromagnetic target (e.g., gear teeth) where the magnetic field sensor is used in combination with a back-biased or other magnet, and a magnetic field sensor that senses a magnetic field density of a magnetic field.
- an angle sensor that senses an angle of a direction of a magnetic field
- a current sensor that senses a magnetic field generated by a current carried by a current-carrying conductor
- a magnetic switch that
- processor or “controller” is used to describe an electronic circuit that performs a function, an operation, or a sequence of operations.
- the function, operation, or sequence of operations can be hard coded into the electronic circuit or soft coded by way of instructions held in a memory device.
- a “processor” can perform the function, operation, or sequence of operations using digital values or using analog signals.
- the “processor” can be embodied in an application specific integrated circuit (ASIC), which can be an analog ASIC or a digital ASIC.
- ASIC application specific integrated circuit
- the “processor” can be embodied in a microprocessor with associated program memory.
- the “processor” can be embodied in a discrete electronic circuit, which can be an analog or digital.
- a processor can contain internal processors or internal modules that perform portions of the function, operation, or sequence of operations of the processor.
- a module can contain internal processors or internal modules that perform portions of the function, operation, or sequence of operations of the module.
- a so-called comparator can comprise an analog comparator having a two state output signal indicative of an input signal being above or below a threshold level (or indicative of one input signal being above or below another input signal).
- the comparator can also comprise a digital circuit having an output signal with at least two states indicative of an input signal being above or below a threshold level (or indicative of one input signal being above or below another input signal), respectively, or a digital value above or below a digital threshold value (or another digital value), respectively.
- FIG. 1 shows a current sensing system 100 for sensing a current in a load 110 such as a motor, LED light, string of lights, or other electrical circuit for which it is desired to measure current.
- the load 110 has a voltage input Vin and/or power input 120 .
- the load 110 has a first ground wire 130 for a first ground (ground 1 ) and a second ground wire 132 for a second ground (ground 2 ).
- ground 1 and/or ground 2 may comprise traces on a circuit board.
- a current sensor 150 may be positioned near the first and second ground wires/conductors 130 , 132 .
- the electrical conductors 130 , 132 are connected to ground or other reference voltage potential through conductors, traces, or wires 160 , 162 . It is understood that in example embodiments the current sensor 150 is placed proximate the current-carrying conductors 130 , 132 , but does not contact or interrupt the conductors.
- the current sensor 150 may be replaced with a differential Hall sensor, as the conductors are outside of the current sensor integrated circuit package.
- a current mismatch between the two ground wires 130 , 132 In a motor application, including AC or DC motor applications, it may be desirable to know when there is a current mismatch between the two ground wires 130 , 132 . In some motor applications this mismatch may be above what may be observed in a typical ground fault interrupt circuit (GFI). As such, the use of a GFI current sensing system would indicate a problem where a problem may not exist in a motor application. For example, in some cases, the current may be 55% to 75% in one current path or ground wire and 25% to 45% in the other current path or ground wire. For example, in some cases the current in ground wires may be split up to 70% in one and 30% in another current path and this would not be a reason for a flag or problem indicator.
- GFI ground fault interrupt circuit
- the current may be acceptable at between 40-60% in each ground wire or current path.
- These current differences may be greater than 100 mA or larger, for example, a current difference may be greater than 1 A or 2 A in certain applications.
- a conventional GFI type of current sensor may not allow the motor to remain operational with these differences in current, as the GFI would typically trip below 25 mA.
- FIG. 2 provides an example of a portion of the current sensing system 100 shown in FIG. 1 .
- a current sensing system 250 includes a circuit board 260 upon which a current sensor integrated circuit (current sensor IC) 280 is mounted.
- Input electrical connection points 262 , 264 may be in the form of a bonding pad, an electrical connector or other terminal, including but not limited to a separate wire soldered to each of circuit board connection points 262 , 264 .
- Current traces 266 , 268 may be patterned on the circuit board, or a hybrid circuit.
- Output electrical connection points 272 , 274 may be provided on the circuit board.
- the current traces 266 , 268 are patterned such that they generate current flow in opposite directions near the current sensor integrated circuit.
- a first current, I 1 flows into electrical connection point 262 through current trace 266 and out of electrical connection point 272 .
- a second current, I 2 flows into electrical connection point 264 through current trace 268 and out of electrical connection point 274 .
- the current traces 266 , 268 are positioned on top of one another in the vicinity of the current sensor 280 , which will be described further in relation to FIG. 2A .
- the current sensor 280 has eight leads 291 , 292 , 293 , 294 , 295 , 296 , 297 , and 298 . These leads contain power input, ground leads, output pins, and other functions that may be desired for a current sensor.
- One lead may be an overcurrent pin and/or a current mismatch pin.
- the current mismatch pin may provide an indication of the current flowing in.
- current sensor 280 may be a packaged integrated circuit with two Hall plates, 285 , 287 , or other magnetic field sensing elements. In the case of planar Hall elements, the first and second Hall elements, or Hall plates, for example, are positioned on opposite sides of the current traces 266 , 268 .
- the electrical current flowing through the current traces 266 , 268 produces magnetic fields which are in opposite directions in FIG. 2 in the area of the current sensor IC 280 . If the two currents are of the same magnitude but in opposite directions the net sum of magnetic field sensed by the Hall plates 285 , 287 is near zero. The actual net magnetic field will depend on the dimensions of the system and the exact position of the magnetic field sensing elements, 285 , 287 , e.g., two Hall plates, and the vertical distance between the first and second traces 266 , 268 . Where the two Hall plates have the same positive sensitivity axis, for example both Hall plates produce a positive voltage for a magnetic field sensed out of the surface of the integrated circuit die.
- FIG. 2A provides a side view of FIG. 2 in the region of the current sensor IC.
- Current sensor system 250 ′ shows the current sensor IC 280 with an integrated circuit die 282 .
- the current sensor IC 280 is mounted to a circuit board 270 .
- Internal leadframe connections of the current sensor IC 280 are not shown for clarity.
- the internal connections of the current sensor IC 280 may include a flip-chip assembly, a typical die on leadframe with wire bond assembly, a lead on chip assembly, or the like.
- current traces 266 , 268 are positioned in or on the circuit board 270 .
- the circuit board 270 includes a substrate 265 upon which a current trace 266 is patterned.
- An insulating layer 267 is placed between current trace 266 and current trace 268 .
- a final insulating layer 269 may be provided to insulate the current trace 268 from any connections, which are not shown for clarity, to the current sensor IC 280 .
- Other electrical traces and connections may be part of the circuit board 270 . They may include, but are not limited to, connections to the current sensor IC 280 on an additional metal layer or layers. In other embodiments the connection to the current sensor IC 280 may be made with conductor layers on the same level as traces 266 or 268 .
- a vertical Hall or giant magnetoresistive (gmr) or other magnetoresistive element (MR) embodiment may have the elements above the current traces 266 , 268 .
- the position of the conductors, 266 , 268 may also be changed to be next to each other rather than on top of each other as shown in FIG. 2A .
- the Hall plates 285 , 287 may be positioned on the same plane of the circuit board. In such a case field measured by the Hall plates may not cancel to zero.
- circuit board may be removed and replaced with wires that connect the motor to a ground or reference voltage in a system directly.
- a circuit board may contain the integrated current sensor package, or die, 280 and have the ground wires from the motor positioned near the current sensor IC with an epoxy attach, tape attach, glue, or mechanical fixture to place the wires or a wiring harness
- each current trace or wire may be replaced by more than one current trace or wire.
- two wires or traces may be represented by ground line 130 and two traces or wires may be represented by ground line 132 in FIG. 1 .
- Other numbers of wires or traces are also possible without departing from the teachings of the present invention.
- FIG. 3 provides an example of a current mismatch circuit 300 that may form part of a current sensor integrated circuit.
- current mismatch circuit 300 includes first and second magnetic field sensing elements 385 , 387 .
- the first magnetic field sensing element 385 and the second magnetic field sensing element 387 may comprise planar Hall plates.
- the magnetic field sensing elements 385 , 387 are connected to first and second amplifiers 310 , 312 respectively.
- the output of the amplifiers 310 , 312 may be summed in a summing element 320 .
- the sum of the two magnetic field sensing elements 385 , 387 is input to a current calculation circuit 330 , which may include a comparator to compare a difference (or sum) of the measured magnetic fields detected by magnetic field sensing elements 385 , 387 .
- the threshold of the comparator in the current calculation circuit 330 may be programmable, such as by the manufacturer or customer.
- the current calculation circuit 330 provides a disconnect output signal 390 that may go to a pin or lead on the current sensor IC.
- the output of the current calculation circuit 330 may be provided to an output circuit as part of the current sensor IC circuit.
- An output circuit in the current sensor IC circuit may allow output in the form of a SENT, I 2 C, or other output format including changing the outputs on pins at a defined clock frequency.
- FIG. 3 also shows an alternative set of connections 314 , 316 , 340 in dotted lines.
- the magnetic field level from the first sensing element 385 may be provided to the current calculation circuit 330 .
- the magnetic field level from the second sensing element 387 may be provided to the current calculation circuit 330 .
- the signals on the traces 314 , 316 may be used to calculate the current in each line to be sensed, for example 266 , 268 on FIG. 2 .
- the current calculation may be output on for example on pins, lines, or traces 340 . In other embodiments, the current in each trace 266 , 268 in FIG. 2 and the sum of the two currents may be output.
- the trace 340 may be expanded into three output pins, lines, or traces, so the current in each of the two writes to be measured can be output, as well as the sum of the current in the two traces.
- Other outputs such as a disconnect output signal may also be present on additional output pins, leads, or traces. Multiple outputs may be combined on one pin, lead or trace as described above with the use of an output protocol.
- the direction of the current in a conductor, or the position of the conductor may result in a sum of the two Hall plates 385 , 387 becoming a difference, for example if the two wires or conductors have current flowing in the same direction.
- one Hall plate would provide a positive Hall voltage, for example Hall plate 385 , for a magnetic field out of the plane of the integrated circuit die, and Hall plate 387 would provide a negative Hall voltage for a magnetic field out of the plane of the integrated circuit die.
- a current sensor integrated circuit die is mounted to a PC board without a package. This may use technics including, but not limited to, flip-chip attachment, and a chip and wire boding to the circuit board, or other support substrate, or flexible circuit.
- a method for determining a current difference between a plurality of conductors in the current sensor system begins at block 405 by providing a current sensor or differential Hall sensor (e.g., current sensor 150 , current sensor integrated circuit 280 ).
- a current sensor or differential Hall sensor e.g., current sensor 150 , current sensor integrated circuit 280 .
- plurality of conductors e.g., 266 , 268 .
- Block 420 compares the current measurement in the plurality of conductors and provides a disconnect output signal.
- processing may be implemented in hardware, software, or a combination of the two.
- Processing may be implemented in computer programs executed on programmable computers/machines that each includes a processor, a storage medium or other article of manufacture that is readable by the processor (including volatile and non-volatile memory and/or storage elements), at least one input device, and one or more output devices.
- Program code may be applied to data entered using an input device to perform processing and to generate output information.
- the system can perform processing, at least in part, via a computer program product, (e.g., in a machine-readable storage device), for execution by, or to control the operation of, data processing apparatus (e.g., a programmable processor, a computer, or multiple computers).
- a computer program product e.g., in a machine-readable storage device
- data processing apparatus e.g., a programmable processor, a computer, or multiple computers.
- Each such program may be implemented in a high-level procedural or object-oriented programming language to communicate with a computer system.
- the programs may be implemented in assembly or machine language.
- the language may be a compiled or an interpreted language and it may be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment.
- a computer program may be deployed to be executed on one computer or on multiple computers at one site or distributed across multiple sites and interconnected by a communication network.
- a computer program may be stored on a storage medium or device (e.g., RAM/ROM, CD-ROM, hard disk, or magnetic diskette) that is readable by a general or special purpose programmable computer for configuring and operating the computer when the storage medium or device is read by the computer.
- a storage medium or device e.g., RAM/ROM, CD-ROM, hard disk, or magnetic diskette
- Processing may also be implemented as a machine-readable storage medium, configured with a computer program, where upon execution, instructions in the computer program cause the computer to operate.
- Processing may be performed by one or more programmable processors executing one or more computer programs to perform the functions of the system. All or part of the system may be implemented as, special purpose logic circuitry (e.g., an FPGA (field programmable gate array), and/or an ASIC (application-specific integrated circuit)).
- special purpose logic circuitry e.g., an FPGA (field programmable gate array), and/or an ASIC (application-specific integrated circuit)
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
- Measuring Magnetic Variables (AREA)
- Hall/Mr Elements (AREA)
Abstract
Description
- Some conventional current sensors are positioned near a current-carrying conductor to sense a magnetic field generated by a current through the conductor. The current sensor generates an output signal having a magnitude proportional to the magnetic field induced by the current through the conductor.
- Some current sensors, such as a ground fault interrupt (GFI) current sensor, are configured to look for small differences in current, typically less than 0.01% of full scale or less than 25 mA, between two conductors. Having a current sensor which can effectively determine when a difference exits between two conductors can be challenging.
- Example embodiments of the disclosure provide methods and apparatus for sensing a current between two or more conductors, or wires, such as a current sensor or a differential magnetic field sensor. In embodiments, as current in a first conductor generates a first magnetic field, and a second current generates a second magnetic field, the difference of these two magnetic fields is compared to a threshold for providing an output to indicate a difference between the first and second currents above a predetermined level.
- In one architecture, the first and second conductors may be conductive traces on a printed circuit board or hybrid circuit. The current sensor may be positioned above the two conductive traces on the circuit board or hybrid circuit.
- The current sensor may contain one or more magnetic field sensing elements, which may comprise a planar Hall element, a vertical Hall element, or a magnetoresistance element, such as a giant magnetoresistance element (GMR), a tunneling magnetoresistance element (TMR) or a magnetic tunnel junction (MTJ), or a combination of magnetic field sensing elements. In an embodiment that uses more than one magnetic field sensing element, at least two magnetic field sensing elements may have an axis of maximum sensitivity configured in the order of about 180 degrees from each other.
- The current sensor may contain a current calculation circuit on the integrated current sensor die to calculate the current flowing in the conductive traces, or wires, as the measured value of the magnetic field combination from the two wire, or positioned so that the current in each wire is measured independently. In embodiments, a disconnect output signal may be generated by the current calculation circuit and provided as an output of the current sensor integrated circuit. In embodiments the output disconnect signal may be activated by a current difference between the two conductors of approximately 10%, 20%, or more.
- A current sensor or differential Hall sensor can be positioned near first and second conductive wires, or traces on printed circuit board or hybrid circuit, to compare the current in the two conductors by measuring the magnetic field generated by the two conductors, either as one measurement or a combination of measuring the two currents independently. An output disconnect signal from the current sensor or the differential Hall sensor can correspond to the current comparison.
- A method may use one or more magnetic field sensing elements to measure the current in the conductive traces. The magnetic field sensing elements may comprise a planar Hall element, a vertical Hall element, or a magnetoresistance element, such as a giant magnetoresistance element (GMR), a tunneling magnetoresistance element (TMR) or magnetic tunnel junction (MTJ), or a combination of magnetic field sensing elements. In an embodiment that uses more than one magnetic field sensing element, at least two magnetic field sensing elements may have an axis of maximum sensitivity configured 180 degrees from each other.
- The method to provide a output disconnect signal from the current sensor or differential Hall sensor integrated circuit may contain a current calculation circuit on the integrated current sensor die to calculate the current flowing in the conductive traces, or wires as the measured value of the magnetic field combination from the two wire, or positioned so that the current in each wire is measured independently. In embodiments, a disconnect output signal may be generated by the current calculation circuit and provided as an output of the current sensor integrated circuit. The method may provide an output disconnect signal activated by a current difference between the two conductors of approximately 10%, 20%, or more. The method may be used to detect a ground or reference voltage disconnect in a motor.
-
FIG. 1 shows a current sensor system with a current sensor IC package; -
FIG. 2 . Is a top view of a current sensor integrated circuit package mounted on a printed circuit board; -
FIG. 2A is a side of a current sensor integrated circuit package mounted on a printed circuit board; -
FIG. 3 is a schematic overview of a circuit for use in the current sensor integrated circuit; and -
FIG. 4 is a flow diagram of a method for determining a current difference between a plurality of conductors in the current sensor system. - As used herein, the term “magnetic field sensing element” is used to describe a variety of electronic elements that can sense a magnetic field. The magnetic field sensing element can be, but is not limited to, a Hall effect element, a magnetoresistance element, or a magnetotransistor. As is known, there are different types of Hall effect elements, for example, a planar Hall element, a vertical Hall element, and a Circular Vertical Hall (CVH) element. As is also known, there are different types of magnetoresistance elements, for example, a semiconductor magnetoresistance element such as Indium Antimonide (InSb), a giant magnetoresistance (GMR) element, for example, a spin valve, an anisotropic magnetoresistance element (AMR), a tunneling magnetoresistance (TMR) element, and a magnetic tunnel junction (MTJ). The magnetic field sensing element may be a single element or, alternatively, may include two or more magnetic field sensing elements arranged in various configurations, e.g., a half-bridge or full (Wheatstone) bridge. Depending on the device type and other application requirements, the magnetic field sensing element may be a device made of a type IV semiconductor material such as Silicon (Si) or Germanium (Ge), or a type III-V semiconductor material like Gallium-Arsenide (GaAs) or an Indium compound, e.g., Indium-Antimonide (InSb).
- As is known, some of the above-described magnetic field sensing elements tend to have an axis of maximum sensitivity parallel to a substrate that supports the magnetic field sensing element, and others of the above-described magnetic field sensing elements tend to have an axis of maximum sensitivity perpendicular to a substrate that supports the magnetic field sensing element. In particular, planar Hall elements tend to have axes of sensitivity perpendicular to a substrate, while metal based or metallic magnetoresistance elements (e.g., GMR, TMR, AMR) and vertical Hall elements tend to have axes of sensitivity parallel to a substrate.
- As used herein, the term “magnetic field sensor” is used to describe a circuit that uses a magnetic field sensing element, generally in combination with other circuits. Magnetic field sensors are used in a variety of applications, including, but not limited to, an angle sensor that senses an angle of a direction of a magnetic field, a current sensor that senses a magnetic field generated by a current carried by a current-carrying conductor, a magnetic switch that senses the proximity of a ferromagnetic object, a rotation detector that senses passing ferromagnetic articles, for example, magnetic domains of a ring magnet or a ferromagnetic target (e.g., gear teeth) where the magnetic field sensor is used in combination with a back-biased or other magnet, and a magnetic field sensor that senses a magnetic field density of a magnetic field.
- As used herein, the term “processor” or “controller” is used to describe an electronic circuit that performs a function, an operation, or a sequence of operations. The function, operation, or sequence of operations can be hard coded into the electronic circuit or soft coded by way of instructions held in a memory device. A “processor” can perform the function, operation, or sequence of operations using digital values or using analog signals. In some embodiments, the “processor” can be embodied in an application specific integrated circuit (ASIC), which can be an analog ASIC or a digital ASIC. In some embodiments, the “processor” can be embodied in a microprocessor with associated program memory. In some embodiments, the “processor” can be embodied in a discrete electronic circuit, which can be an analog or digital. A processor can contain internal processors or internal modules that perform portions of the function, operation, or sequence of operations of the processor. Similarly, a module can contain internal processors or internal modules that perform portions of the function, operation, or sequence of operations of the module.
- While electronic circuits shown in figures herein may be shown in the form of analog blocks or digital blocks, it will be understood that the analog blocks can be replaced by digital blocks that perform the same or similar functions and the digital blocks can be replaced by analog blocks that perform the same or similar functions. Analog-to-digital or digital-to-analog conversions may not be explicitly shown in the figures, but will be readily understood by one of ordinary skill in the art.
- In particular, it should be understood that a so-called comparator can comprise an analog comparator having a two state output signal indicative of an input signal being above or below a threshold level (or indicative of one input signal being above or below another input signal). However, the comparator can also comprise a digital circuit having an output signal with at least two states indicative of an input signal being above or below a threshold level (or indicative of one input signal being above or below another input signal), respectively, or a digital value above or below a digital threshold value (or another digital value), respectively.
-
FIG. 1 shows acurrent sensing system 100 for sensing a current in aload 110 such as a motor, LED light, string of lights, or other electrical circuit for which it is desired to measure current. Theload 110 has a voltage input Vin and/orpower input 120. In embodiments, theload 110 has afirst ground wire 130 for a first ground (ground 1) and asecond ground wire 132 for a second ground (ground 2). In embodiments,ground 1 and/orground 2 may comprise traces on a circuit board. Acurrent sensor 150 may be positioned near the first and second ground wires/conductors current sensor 150, theelectrical conductors wires current sensor 150 is placed proximate the current-carryingconductors - In another embodiment the
current sensor 150 may be replaced with a differential Hall sensor, as the conductors are outside of the current sensor integrated circuit package. - In a motor application, including AC or DC motor applications, it may be desirable to know when there is a current mismatch between the two
ground wires -
FIG. 2 provides an example of a portion of thecurrent sensing system 100 shown inFIG. 1 . In embodiments, acurrent sensing system 250 includes acircuit board 260 upon which a current sensor integrated circuit (current sensor IC) 280 is mounted. Input electrical connection points 262, 264 may be in the form of a bonding pad, an electrical connector or other terminal, including but not limited to a separate wire soldered to each of circuit board connection points 262, 264. Current traces 266, 268 may be patterned on the circuit board, or a hybrid circuit. Output electrical connection points 272, 274 may be provided on the circuit board. In embodiments, thecurrent traces electrical connection point 262 throughcurrent trace 266 and out ofelectrical connection point 272. A second current, I2, flows intoelectrical connection point 264 throughcurrent trace 268 and out ofelectrical connection point 274. In one embodiment thecurrent traces current sensor 280, which will be described further in relation toFIG. 2A . - In the illustrated embodiment, the
current sensor 280 has eightleads current sensor 280 may be a packaged integrated circuit with two Hall plates, 285, 287, or other magnetic field sensing elements. In the case of planar Hall elements, the first and second Hall elements, or Hall plates, for example, are positioned on opposite sides of thecurrent traces - The electrical current flowing through the
current traces FIG. 2 in the area of thecurrent sensor IC 280. If the two currents are of the same magnitude but in opposite directions the net sum of magnetic field sensed by theHall plates second traces -
FIG. 2A provides a side view ofFIG. 2 in the region of the current sensor IC.Current sensor system 250′ shows thecurrent sensor IC 280 with an integrated circuit die 282. Thecurrent sensor IC 280 is mounted to acircuit board 270. Internal leadframe connections of thecurrent sensor IC 280 are not shown for clarity. The internal connections of thecurrent sensor IC 280 may include a flip-chip assembly, a typical die on leadframe with wire bond assembly, a lead on chip assembly, or the like. In the illustrated embodiment,current traces circuit board 270. In one example, thecircuit board 270 includes asubstrate 265 upon which acurrent trace 266 is patterned. An insulatinglayer 267 is placed betweencurrent trace 266 andcurrent trace 268. A final insulatinglayer 269 may be provided to insulate thecurrent trace 268 from any connections, which are not shown for clarity, to thecurrent sensor IC 280. Other electrical traces and connections may be part of thecircuit board 270. They may include, but are not limited to, connections to thecurrent sensor IC 280 on an additional metal layer or layers. In other embodiments the connection to thecurrent sensor IC 280 may be made with conductor layers on the same level astraces - In other embodiments, other types of magnetic field sensing elements may be used. The position of the sensing elements may be moved without departing from the scope of the claimed invention in order to place the magnetic field sensing elements in a position where they can sense the magnetic field. For example, a vertical Hall or giant magnetoresistive (gmr) or other magnetoresistive element (MR) embodiment may have the elements above the
current traces - The position of the conductors, 266, 268 may also be changed to be next to each other rather than on top of each other as shown in
FIG. 2A . In one example theHall plates - In another embodiment current traces on the circuit board may be removed and replaced with wires that connect the motor to a ground or reference voltage in a system directly. In such a case a circuit board may contain the integrated current sensor package, or die, 280 and have the ground wires from the motor positioned near the current sensor IC with an epoxy attach, tape attach, glue, or mechanical fixture to place the wires or a wiring harness
- In other embodiments, each current trace or wire may be replaced by more than one current trace or wire. For example, two wires or traces may be represented by
ground line 130 and two traces or wires may be represented byground line 132 in FIG. 1. Other numbers of wires or traces are also possible without departing from the teachings of the present invention. -
FIG. 3 provides an example of acurrent mismatch circuit 300 that may form part of a current sensor integrated circuit. In example embodiments,current mismatch circuit 300 includes first and second magneticfield sensing elements field sensing element 385 and the second magneticfield sensing element 387, may comprise planar Hall plates. The magneticfield sensing elements second amplifiers amplifiers element 320. The sum of the two magneticfield sensing elements current calculation circuit 330, which may include a comparator to compare a difference (or sum) of the measured magnetic fields detected by magneticfield sensing elements current calculation circuit 330 may be programmable, such as by the manufacturer or customer. Thecurrent calculation circuit 330 provides adisconnect output signal 390 that may go to a pin or lead on the current sensor IC. - In another embodiment, the output of the
current calculation circuit 330 may be provided to an output circuit as part of the current sensor IC circuit. An output circuit in the current sensor IC circuit may allow output in the form of a SENT, I2C, or other output format including changing the outputs on pins at a defined clock frequency. -
FIG. 3 also shows an alternative set ofconnections first sensing element 385, may be provided to thecurrent calculation circuit 330. The magnetic field level from thesecond sensing element 387 may be provided to thecurrent calculation circuit 330. The signals on thetraces FIG. 2 . The current calculation may be output on for example on pins, lines, or traces 340. In other embodiments, the current in eachtrace FIG. 2 and the sum of the two currents may be output. In some embodiments thetrace 340 may be expanded into three output pins, lines, or traces, so the current in each of the two writes to be measured can be output, as well as the sum of the current in the two traces. Other outputs such as a disconnect output signal may also be present on additional output pins, leads, or traces. Multiple outputs may be combined on one pin, lead or trace as described above with the use of an output protocol. - In another embodiment the direction of the current in a conductor, or the position of the conductor may result in a sum of the two
Hall plates example Hall plate 385, for a magnetic field out of the plane of the integrated circuit die, andHall plate 387 would provide a negative Hall voltage for a magnetic field out of the plane of the integrated circuit die. - In another embodiment, a current sensor integrated circuit die is mounted to a PC board without a package. This may use technics including, but not limited to, flip-chip attachment, and a chip and wire boding to the circuit board, or other support substrate, or flexible circuit.
- Referring to
FIG. 4 , a method for determining a current difference between a plurality of conductors in the current sensor system (e.g.,system 100, 250) begins atblock 405 by providing a current sensor or differential Hall sensor (e.g.,current sensor 150, current sensor integrated circuit 280). Atblock 410, plurality of conductors (e.g., 266, 268) are provided, each of the conductors carrying a current to be measured. - At
block 415, the magnetic field generated by the current in the plurality of conductors is measured.Block 420 compares the current measurement in the plurality of conductors and provides a disconnect output signal. - It is understood that any of the above-described processing may be implemented in hardware, software, or a combination of the two. Processing may be implemented in computer programs executed on programmable computers/machines that each includes a processor, a storage medium or other article of manufacture that is readable by the processor (including volatile and non-volatile memory and/or storage elements), at least one input device, and one or more output devices. Program code may be applied to data entered using an input device to perform processing and to generate output information.
- The system can perform processing, at least in part, via a computer program product, (e.g., in a machine-readable storage device), for execution by, or to control the operation of, data processing apparatus (e.g., a programmable processor, a computer, or multiple computers). Each such program may be implemented in a high-level procedural or object-oriented programming language to communicate with a computer system. However, the programs may be implemented in assembly or machine language. The language may be a compiled or an interpreted language and it may be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program may be deployed to be executed on one computer or on multiple computers at one site or distributed across multiple sites and interconnected by a communication network. A computer program may be stored on a storage medium or device (e.g., RAM/ROM, CD-ROM, hard disk, or magnetic diskette) that is readable by a general or special purpose programmable computer for configuring and operating the computer when the storage medium or device is read by the computer.
- Processing may also be implemented as a machine-readable storage medium, configured with a computer program, where upon execution, instructions in the computer program cause the computer to operate.
- Processing may be performed by one or more programmable processors executing one or more computer programs to perform the functions of the system. All or part of the system may be implemented as, special purpose logic circuitry (e.g., an FPGA (field programmable gate array), and/or an ASIC (application-specific integrated circuit)).
- Having described exemplary embodiments of the disclosure, it will now become apparent to one of ordinary skill in the art that other embodiments incorporating their concepts may also be used. The embodiments contained herein should not be limited to disclosed embodiments but rather should be limited only by the spirit and scope of the appended claims. All publications and references cited herein are expressly incorporated herein by reference in their entirety.
- Elements of different embodiments described herein may be combined to form other embodiments not specifically set forth above. Various elements, which are described in the context of a single embodiment, may also be provided separately or in any suitable subcombination. Other embodiments not specifically described herein are also within the scope of the following claims.
Claims (31)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US17/083,487 US11320466B1 (en) | 2020-10-29 | 2020-10-29 | Differential current sensor |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US17/083,487 US11320466B1 (en) | 2020-10-29 | 2020-10-29 | Differential current sensor |
Publications (2)
Publication Number | Publication Date |
---|---|
US11320466B1 US11320466B1 (en) | 2022-05-03 |
US20220137103A1 true US20220137103A1 (en) | 2022-05-05 |
Family
ID=81380980
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US17/083,487 Active US11320466B1 (en) | 2020-10-29 | 2020-10-29 | Differential current sensor |
Country Status (1)
Country | Link |
---|---|
US (1) | US11320466B1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20240266819A1 (en) * | 2021-07-05 | 2024-08-08 | Phoenix Contact Gmbh & Co. Kg | Residual current monitoring for a dc voltage switching device |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11885866B2 (en) | 2022-05-31 | 2024-01-30 | Allegro Microsystems, Llc | Auto-calibration for coreless current sensors |
US11940470B2 (en) | 2022-05-31 | 2024-03-26 | Allegro Microsystems, Llc | Current sensor system |
US12078662B2 (en) * | 2022-06-27 | 2024-09-03 | Allegro Microsystems, Llc | Techniques for reducing an eddy current in a ground plane of a coreless sensor |
Family Cites Families (35)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2004075311A1 (en) | 1998-10-02 | 2004-09-02 | Sanken Electric Co., Ltd. | Semiconductor device with hall-effect element |
JP2000174357A (en) | 1998-10-02 | 2000-06-23 | Sanken Electric Co Ltd | Semiconductor device containing hall-effect element |
JP2001165963A (en) | 1999-12-09 | 2001-06-22 | Sanken Electric Co Ltd | Current detecting device |
JP3852554B2 (en) | 1999-12-09 | 2006-11-29 | サンケン電気株式会社 | Current detection device with Hall element |
JP4164615B2 (en) | 1999-12-20 | 2008-10-15 | サンケン電気株式会社 | CURRENT DETECTOR HAVING HALL ELEMENT |
JP3230580B2 (en) | 2000-02-04 | 2001-11-19 | サンケン電気株式会社 | Current detection device equipped with a ball element |
JP4025958B2 (en) | 2000-05-17 | 2007-12-26 | サンケン電気株式会社 | CURRENT DETECTOR HAVING HALL ELEMENT |
JP2001339109A (en) | 2000-05-26 | 2001-12-07 | Sanken Electric Co Ltd | Current sensing device equipped with hall element |
JP2002026419A (en) | 2000-07-07 | 2002-01-25 | Sanken Electric Co Ltd | Magnetism-electricity conversion device |
JP2002202327A (en) | 2000-10-23 | 2002-07-19 | Sanken Electric Co Ltd | Current detector equipped with hall element |
JP4164629B2 (en) | 2000-10-23 | 2008-10-15 | サンケン電気株式会社 | Current detection device with Hall element |
JP4164626B2 (en) | 2001-06-15 | 2008-10-15 | サンケン電気株式会社 | CURRENT DETECTOR HAVING HALL ELEMENT |
EP1267173A3 (en) | 2001-06-15 | 2005-03-23 | Sanken Electric Co., Ltd. | Hall-effect current detector |
DE60219561T2 (en) | 2001-07-06 | 2008-01-03 | Sanken Electric Co. Ltd., Niiza | Hall effect current detector |
JP3896590B2 (en) | 2002-10-28 | 2007-03-22 | サンケン電気株式会社 | Current detector |
JP2004207477A (en) | 2002-12-25 | 2004-07-22 | Sanken Electric Co Ltd | Semiconductor device having hall element |
US20060219436A1 (en) * | 2003-08-26 | 2006-10-05 | Taylor William P | Current sensor |
US20070279053A1 (en) | 2006-05-12 | 2007-12-06 | Taylor William P | Integrated current sensor |
US7816905B2 (en) | 2008-06-02 | 2010-10-19 | Allegro Microsystems, Inc. | Arrangements for a current sensing circuit and integrated current sensor |
US9222992B2 (en) * | 2008-12-18 | 2015-12-29 | Infineon Technologies Ag | Magnetic field current sensors |
US8400139B2 (en) * | 2010-03-26 | 2013-03-19 | Infineon Technologies Ag | Sensor package having a sensor chip |
US8907437B2 (en) | 2011-07-22 | 2014-12-09 | Allegro Microsystems, Llc | Reinforced isolation for current sensor with magnetic field transducer |
US8896295B2 (en) | 2012-04-04 | 2014-11-25 | Allegro Microsystems, Llc | Magnetic field sensor having multiple sensing elements and a programmable misalignment adjustment device for misalignment detection and correction in current sensing and other applications |
US9007054B2 (en) | 2012-04-04 | 2015-04-14 | Allegro Microsystems, Llc | Angle sensor with misalignment detection and correction |
US9081041B2 (en) | 2012-04-04 | 2015-07-14 | Allegro Microsystems, Llc | High accuracy differential current sensor for applications like ground fault interrupters |
US20140266180A1 (en) * | 2013-03-15 | 2014-09-18 | Infineon Technologies Ag | Sensors, systems and methods for residual current detection |
JP6194466B2 (en) | 2013-04-11 | 2017-09-13 | パナソニックIpマネジメント株式会社 | Motor drive device |
WO2016210287A1 (en) * | 2015-06-24 | 2016-12-29 | The University Of North Carolina At Charlotte | Contactless wideband magneto-resistive current sensor with low electromagnetic interference |
US10533877B2 (en) * | 2017-02-17 | 2020-01-14 | Infineon Technologies Ag | Angle sensor with disturbance field suppression |
US10520559B2 (en) * | 2017-08-14 | 2019-12-31 | Allegro Microsystems, Llc | Arrangements for Hall effect elements and vertical epi resistors upon a substrate |
EP3644069A1 (en) * | 2018-10-24 | 2020-04-29 | Melexis Technologies SA | Insulated current sensor |
US10955306B2 (en) * | 2019-04-22 | 2021-03-23 | Allegro Microsystems, Llc | Coil actuated pressure sensor and deformable substrate |
US11150110B2 (en) * | 2019-08-01 | 2021-10-19 | Allegro Microsystems, Llc | Sensor having a shaped coil |
US11150273B2 (en) * | 2020-01-17 | 2021-10-19 | Allegro Microsystems, Llc | Current sensor integrated circuits |
US11226382B2 (en) * | 2020-04-07 | 2022-01-18 | Allegro Microsystems, Llc | Current sensor system |
-
2020
- 2020-10-29 US US17/083,487 patent/US11320466B1/en active Active
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20240266819A1 (en) * | 2021-07-05 | 2024-08-08 | Phoenix Contact Gmbh & Co. Kg | Residual current monitoring for a dc voltage switching device |
Also Published As
Publication number | Publication date |
---|---|
US11320466B1 (en) | 2022-05-03 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US11320466B1 (en) | Differential current sensor | |
US10908190B2 (en) | Systems and methods for current sensing | |
US10908232B2 (en) | Gain equalization for multiple axis magnetic field sensing | |
EP3786657A2 (en) | Dual magnetoresistance element with two directions of response to external magnetic fields | |
US9958482B1 (en) | Systems and methods for a high isolation current sensor | |
US9605979B2 (en) | Magnetic field sensor with magnetoresistance elements and conductive trace magnetic source | |
US9739850B2 (en) | Push-pull flipped-die half-bridge magnetoresistive switch | |
CN111308153A (en) | Current sensor with integrated current conductor | |
US11519946B1 (en) | Packaged current sensor integrated circuit | |
US11561112B2 (en) | Current sensor having stray field immunity | |
CN113376422B (en) | Current sensor for improving functional safety | |
US20190113584A1 (en) | Efficient Signal Path Diagnostics For Safety Devices | |
EP4063872A1 (en) | Differential current sensor package | |
US10914765B1 (en) | Multi-die integrated current sensor | |
US10763219B2 (en) | Signal conductor routing configurations and techniques | |
US20230060219A1 (en) | Packaged current sensor integrated circuit | |
US20240003995A1 (en) | Sensor package and system | |
EP3594704B1 (en) | Integrated circuit with connectivity error detection | |
US11892476B2 (en) | Current sensor package | |
US11899047B1 (en) | Magnetic field shaping for magnetic field current sensor | |
US20240133981A1 (en) | Dual current magnetic field sensor | |
US11768229B2 (en) | Packaged current sensor integrated circuit | |
US20230184865A1 (en) | Hybrid hall-effect/magnetoresistance (mr) magnetometer with self-calibration | |
US11791083B2 (en) | Tunnel magneto-resistive (TMR) sensor with perpendicular magnetic tunneling junction (p-MTJ) structures |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
FEPP | Fee payment procedure |
Free format text: ENTITY STATUS SET TO UNDISCOUNTED (ORIGINAL EVENT CODE: BIG.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
AS | Assignment |
Owner name: ALLEGRO MICROSYSTEMS, LLC, NEW HAMPSHIRE Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:BRIANO, ROBERT A.;BUSSING, WADE;CLARK, TIMOTHY A.;REEL/FRAME:054236/0875 Effective date: 20201028 |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
AS | Assignment |
Owner name: MORGAN STANLEY SENIOR FUNDING, INC., AS THE COLLATERAL AGENT, MARYLAND Free format text: PATENT SECURITY AGREEMENT;ASSIGNOR:ALLEGRO MICROSYSTEMS, LLC;REEL/FRAME:064068/0459 Effective date: 20230621 |