SELF-CALITING CURRENT SENSOR PACKAGE

Abstract

In the present disclosure, a current sensor package (100) with self-calibration functionality is proposed. No external microcontroller is required. The current sensor package (100) comprises an integrated current sensor circuit (102) configured to generate an analog sensor signal (104) in response to an electric current. The current sensor package (100) includes an ADC (108) coupled to the integrated current sensor circuit (102) and configured to convert the analog sensor signal (104) into a digital sensor signal (110). The current sensor package (100) includes a digital processor (112) coupled to the ADC (108) and configured to implement / perform a calibration procedure for the integrated current sensor circuit (102) based on the digital sensor signal (110) and predefined target values.The current sensor package (100) includes a non-volatile memory (114) coupled with the digital processor (112) and configured to store the predefined target values ​​and calibration parameters found during the calibration procedure.

Description

Area

[0001] The present disclosure relates to current sensors and, more particularly, to the calibration of integrated current sensors. background

[0002] A current sensor is an electronic device that measures the amount of alternating and / or direct current flowing through a conductor. Current sensors can be used in a wide variety of applications, including power electronics, motor control, energy management systems, and industrial automation. They can provide information about the behavior of electrical systems, allowing their performance to be monitored, controlled, and optimized.

[0003] Integrated current sensors can be more compact, efficient, and cost-effective than discrete sensors because they eliminate the need for discrete circuit components and simplify electronic system design. Furthermore, integrated current sensors can offer features such as programmable gain and bandwidth, temperature compensation, and digital output signals that can be easily interfaced with other electronic components, such as microcontrollers.

[0004] A coreless current sensor is a type of current sensor that measures the amount of electric current flowing through a conductor without using a magnetic core. Instead of using a core, coreless current sensors can rely on the principles of the Hall effect, magnetic induction, or some type of magnetoresistance such as TMR (tunneling magnetoresistance) to detect the presence of current. Coreless current sensors can be smaller and lighter than their conventional counterparts, making them more suitable for applications where space and weight are at a premium. Additionally, coreless current sensors can be more precise and have a faster response time than conventional sensors. Several types of coreless current sensors are available, including Hall effect sensors, fluxgate sensors, and magnetoresistive sensors.Hall-effect sensors use a magnetic field to detect the presence of current, while fluxgate sensors use a coil to measure changes in magnetic flux. Magnetoresistive sensors, on the other hand, use changes in the resistance of a magnetic material to measure changes in magnetic field strength.

[0005] Current sensors typically provide an output signal proportional to the measured current. This signal can be in the form of a voltage, current, or frequency output, depending on the type of sensor and the application.

[0006] Current sensors can exhibit initial offset and sensitivity errors due to part-to-part variations resulting from manufacturing steps. Furthermore, current sensors can be prone to errors due to mechanical displacements and manufacturing tolerances, making the initial offset and sensitivity errors even more significant overall. For this reason, an end-of-line (EOL) calibration is typically required in the system.

[0007] End-of-life calibration is a type of calibration process that can be performed during or after manufacturing a current sensor to ensure that the sensor's output is within its specified accuracy limits. End-of-life calibration typically involves testing the sensor's output against a known reference current source at various points throughout the sensor's operating range. Any differences between the sensor's output and a reference current can be recorded, and adjustments can be made to the sensor's circuitry to bring its output signal into line with the reference current. The calibration process may involve adjusting the gain, offset, or linearity of the sensor's output, depending on the sensor's type and design.Furthermore, it may be important to calibrate current sensors periodically to ensure they continue to provide accurate and reliable measurements over time. The calibration frequency depends on factors such as the type of sensor, the operating environment, and the criticality of the measurements taken.

[0008] The exact process for end-of-line (EOL) calibration of a current sensor can vary depending on the specific type of sensor and its manufacturer. However, a typical EOL calibration process for a current sensor might include the following steps: - Setting up a test system: The current sensor is connected to an external test system that includes a known reference current source and any necessary external instrumentation to measure and record the sensor's output signal. - Applying test currents: The reference current source is used to apply a range of test currents to the sensor that covers at least a portion of the sensor's operating range. - Recording the sensor output: The sensor output signal is measured and recorded for each applied test current. - Compare with the reference: The recorded sensor output signals are compared with the known reference currents, and any differences between the sensor output and the reference are calculated and recorded. - Adjusting the sensor output: Based on the recorded differences between the sensor output and the reference, adjustments can be made to the sensor circuitry or its output to bring its output signal into line with the reference current.

[0009] Traditionally, calibration parameters can be measured and stored either in a microcontroller or directly in the sensor EEPROM at the end of life via a digital interface between the sensor and the microcontroller. Therefore, a user must implement a sensor's digital communication interface and calibration coefficient calculation, resulting in additional time and effort.

[0010] Thus, there is a need for an improved concept for calibrating integrated current sensors. Summary

[0011] This need is met by current sensor packages and methods according to the appended claims.

[0012] According to a first aspect, the present disclosure proposes a current sensor package. The current sensor package includes an integrated current sensor circuit configured to generate an analog sensor signal in response to an electrical current. The current sensor package further includes an analog-to-digital converter (ADC) coupled to the integrated current sensor circuit and configured to convert the analog sensor signal into a digital sensor signal. The current sensor package further includes a digital processor coupled to the ADC and configured to perform a calibration procedure for the integrated current sensor circuit based on the digital sensor signal and predefined target values.The current sensor package further includes a non-volatile memory coupled to the digital processor and configured to store the predefined target values ​​and calibration parameters found during the calibration procedure.

[0013] According to embodiments of the present disclosure, a current sensor calibration routine can be implemented directly in the current sensor package, which can provide a protective and functional housing for one or more semiconductor dies implementing the circuit components in the current sensor package. This eliminates the need for the user to implement the calibration logic in an external microcontroller. The current sensor package includes at least the integrated ADC coupled to an AOUT (analog output) of the current sensor package, an integrated non-volatile memory in which calibration parameters for sensitivity and offset can be stored, and an integrated digital core implementing the calibration algorithm.

[0014] In some embodiments, the integrated current sensor circuit of the current sensor package includes a sensing element and signal conditioning circuitry configured to process an analog output signal from the sensing element. The sensing element may comprise a coil, a magnetoresistor, or a Hall-effect sensor. The signal conditioning circuitry may include an amplifier configured to amplify the analog output signal of the sensing element.

[0015] In some embodiments, the ADC in the current sensor package has a bit width of at least 6 bits. This allows for a low quantization error for the analog-to-digital conversion of the analog output signal from the sensing element.

[0016] In some embodiments, the digital processor in the current sensor package is configured to start the calibration procedure when at least one terminal or pin of the current sensor package is set to a predefined state for a predefined time. The predefined state may, for example, correspond to a predefined voltage.

[0017] In some embodiments, the digital processor in the current sensor package is configured to determine, during the calibration procedure, an offset value of the integrated current sensor circuit and a sensitivity value of the integrated current sensor circuit based on a predefined electrical current, the digital sensor signal responsive to the predefined electrical current, and the offset value. The offset value can be caused by a variety of factors, including temperature variations, magnetic interference, manufacturing variations, electrical noise, aging and degradation, or mechanical stress. The sensitivity of a current sensor can be influenced by various factors, including a distance between the current-carrying conductor and the sensor, a frequency of the measured current, an ambient temperature, or electrical noise.

[0018] In some embodiments, the non-volatile memory is configured in the current sensor package to store one or more correction factors required to obtain a target sensitivity and a target offset of the integrated current sensor circuit. The non-volatile memory may comprise an EEPROM (Electrically Erasable Programmable Read-Only Memory) that can be electrically programmed and erased.

[0019] In some embodiments, the integrated current sensor circuit, the ADC, the digital processor, and the non-volatile memory are all integrated on a common semiconductor substrate / semiconductor die. That is, the current sensor package may house a semiconductor die that integrates the current sensor circuit, the ADC, the digital processor, and the non-volatile memory.

[0020] In some embodiments, the current sensor package may further include a power rail integrated into the current sensor package. That is, the current sensor package may either include an integrated power rail within the package for low currents or measure the magnetic field of an external power rail for medium to high currents.

[0021] According to a further aspect, the present disclosure also proposes a method for calibrating a current sensor package. The method comprises - generating, using a current sensor circuit integrated into the current sensor package, an analog sensor signal in response to an electrical current, - Converting the analog sensor signal into a digital sensor signal using an ADC integrated into the current sensor package, - Performing, on a digital processor integrated in the current sensor package, a calibration procedure for the integrated current sensor circuit based on the digital sensor signal and predefined target values, and - Saving the predefined target values ​​and calibration parameters found during the calibration procedure on a non-volatile memory integrated into the current sensor package.

[0022] In some embodiments, the method may further comprise initiating the calibration procedure by setting at least one terminal or pin of the current sensor package to a predefined state (e.g., a predefined voltage) for a predefined time.

[0023] In some embodiments, performing the calibration procedure in the digital processor within a predefined time window from initiating the calibration procedure includes measuring an offset value of the integrated current sensor circuit under the assumption that no electrical current is present in a measurement path.

[0024] In some embodiments, performing the calibration procedure in the digital processor comprises, after the predefined time window from initiating the calibration procedure, forcing a predefined test current in the measurement path and calculating a sensitivity value of the integrated current sensor circuit based on the predefined test current, the digital sensor signal responsive to the predefined test current, and the offset value.

[0025] In some embodiments, performing the calibration procedure in the digital processor includes calculating one or more correction factors required to obtain a target sensitivity and a target offset of the current sensor integrated circuit and storing the one or more correction factors in the non-volatile memory.

[0026] Thus, embodiments of the present disclosure propose a current sensor calibration concept in which the sensor itself automatically corrects the sensitivity and offset according to the target sensitivity and target offset required by the system. Short description of the characters

[0027] Some examples of devices and / or methods are described below solely by way of example and with reference to the accompanying figures, in which: Fig. 1 shows a block diagram of a current sensor package with self-calibration capability; and Fig. Figure 2 shows a flowchart of a self-calibration procedure for a current sensor package. Detailed description

[0028] Some examples will now be described in more detail with reference to the accompanying figures. However, other possible examples are not limited to the features of these detailed embodiments. Other examples may include modifications of the features, as well as equivalents and alternatives to the features. Furthermore, the terminology used herein to describe specific examples is not intended to be limiting of other possible examples.

[0029] Throughout the description of the figures, identical or similar reference numerals refer to identical or similar elements and / or features, which may be implemented identically or in a modified form while providing the same or a similar function. Furthermore, in the figures, the thicknesses of lines, layers, and / or regions may be exaggerated for clarity.

[0030] When two elements A and B are combined using "or," this is to be understood as disclosing all possible combinations, i.e., only A, only B, and A and B, unless explicitly defined otherwise in the individual case. Alternative wording for the same combinations may be "at least one of A and B" or "A and / or B." This applies accordingly to combinations of more than two elements.

[0031] If a singular form is used, such as "a," "an," and "the," and the use of only a single element is neither explicitly nor implicitly defined as mandatory, further examples may also use multiple elements to implement the same function. If a function is subsequently described as being implemented using multiple elements, further examples may implement the same function using a single element or a single processing entity.It is further understood that the terms "comprises", "comprising", "has" and / or "having" when used describe the presence of the specified features, integers, steps, operations, processes, elements, components and / or a group thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, processes, elements, components and / or a group thereof.

[0032] Electric current is an important physical quantity whose measurement is required in many applications, be it industrial, automotive, or household. Various technical solutions for measuring currents are known. Due to the galvanic isolation between a sensed circuit and a measuring circuitry, current sensing using Hall-effect ICs (integrated circuits) can be a good choice for many applications.

[0033] An electric current creates a magnetic field around a conductor. The direction can be determined using the “right-hand rule.” The field strength, expressed in A / m, is directly proportional to the current and decreases linearly with increasing distances according to H=l2πr.

[0034] Using B = µ0µ r H, the flux density can then be expressed as B=μ0μrl2πr where the material permeability µr for air is almost one and the free space permeability µ0 = 4π·10 -7 Vs / Am is a constant. Flux density, for example, can be conveniently measured using an integrated Hall-effect IC. Unlike a shunt solution, current measurements using the Hall effect have no resistance immersed in the primary circuit, and accordingly, there is no voltage drop or power loss. The measurement circuit can be completely independent and galvanically isolated; the only power consumed is that of the Hall-effect sensor.

[0035] Since there is an interest in obtaining a continuous signal proportional to the current, the devices to be used can be so-called linear Hall sensors. These devices provide an output signal that is a linear function of the magnetic flux density passing perpendicularly through their Hall plate. In modern linear Hall ICs, a Hall plate can be integrated along with high-precision readout and compensation circuitry on a single piece of silicon.

[0036] Although direct measurement of a conductor's magnetic field is possible, in practice it may be advisable to use a field concentrator to both concentrate and amplify the magnetic flux. Furthermore, this soft magnetic concentrator can help make the setup less susceptible to mechanical misalignment.

[0037] Linear Hall sensors can detect the flux density, and the sensor output can be programmable in the form AOUT=SB+O, where S is the sensor's sensitivity and O is the offset. These two parameters are programmable, meaning any first-order transfer function can be selected (within the parameter range limits) to match the required measurement range. The sensitivity and offset are programmable, thus allowing for any variations due to production variation to be calibrated out.

[0038] The block diagram of Fig. 1 shows, as an illustrative example, a current sensor package 100 according to the present disclosure.

[0039] The current sensor package 100 may be an enclosure enclosing one or more semiconductor chips or integrated circuits (ICs) and may provide electrical connections (pins) to the outside world. The current sensor package 100 may protect enclosed sensitive semiconductor components from damage, provide mechanical support, and assist in thermal management. The current sensor package 100 may also provide means for mounting the package 100 on printed circuit boards or other substrates.

[0040] The current sensor package 100 includes an integrated current sensor circuit 102 configured to generate an analog sensor signal 104 in response to an electrical current flowing through a power rail 106. The power rail 106 may be external or internal to the current sensor package 100.

[0041] The current sensor circuit 102 integrated into the current sensor package 100 may include one or more current sensing elements, such as Hall-effect sensing elements, inductive sensing elements (coils), one or more magnetoresistive sensing elements, or combinations thereof. A Hall-effect sensing element is a type of coreless current sensor that uses the Hall effect to measure the magnetic field generated by the current through the power rail 106. Hall-effect sensors may include a thin plate of semiconductor material with a current-carrying conductor placed perpendicular to its surface. When a magnetic field is applied, it deflects the flow of electrons in the semiconductor, creating a voltage across the conductor that is proportional to the magnetic field and, therefore, to the current through the power rail 106.A magnetoresistive sensing element is a type of coreless current sensor that uses a magnetoresistive effect to measure the magnetic field generated by the current through the bus bar 106. Magnetoresistive effects include anisotropic magnetoresistance (AMR), giant magnetoresistance (GMR), or tunnel magnetoresistance (TMR). A magnetoresistive sensor may comprise a thin layer stack of magnetic and non-magnetic material whose resistance varies with the applied magnetic field. The current flowing through the bus bar 106 generates a magnetic field that is detected by the magnetoresistive element, producing an output signal proportional to the current. It is also conceivable for the current sensor circuit 102 to comprise an inductive current sensor and use one or more coils as sensing elements.

[0042] The current sensor circuit 102 may include additional circuit components in addition to one or more current sensing elements. For example, the integrated current sensor circuit 102 in the current sensor package 100 may include signal conditioning circuitry configured to process an analog output signal from the sensing element(s). Signal conditioning circuitry may be circuitry that processes the analog sensor signal from the sensing element(s) to make it suitable for further processing or measurement. The analog sensor signal from the sensing element is typically a low voltage or current proportional to the measured current. However, this signal may be noisy, have a low signal-to-noise ratio, or be incompatible with the input requirements of subsequent circuitry.Therefore, a signal conditioning circuit can be used to improve the quality of the signal and adapt it to the requirements of the next processing stage. The specific design of a signal conditioning circuit for a current sensor depends on the type of current sensor and the application requirements. However, some common functions of signal conditioning circuits for current sensors include amplification, filtering, linearization, or conversion (e.g., voltage-to-current conversion, current-to-voltage conversion).

[0043] The current sensor package 100 further includes an ADC 108 coupled to the output of the integrated current sensor circuit 102 and configured to convert the analog sensor signal 104 into a digital sensor signal 110. The ADC 108 may be present in various possible implementations. For example, the ADC 108 may be a delta-sigma ADC. This type of ADC uses oversampling and noise shaping techniques to convert the analog signal 104 into the digital sensor signal 110. It may sample the input signal at a very high rate and then filter the resulting digital signal to remove the noise. The ADC 108 in the current sensor package 100 may, for example, have a bit width of at least 6 bits. In this way, a quantization error for analog-to-digital conversion of the analog sensor signal 104 can be kept low.

[0044] The current sensor package 100 further includes a digital processor 112 coupled to the output of the ADC 108 and configured to implement an automatic calibration procedure for the integrated current sensor circuit 102 based on the digital sensor signal 110 and based on predefined target values ​​(e.g., for sensitivity and offset). For this purpose, the current sensor package 100 further includes a non-volatile memory 114 coupled to the digital processor 112 and configured to store the predefined target values ​​and calibration / correction parameters found during the calibration procedure.

[0045] The digital processor 112 may be an integrated digital core of the current sensor package 100. It refers to the part of the current sensor package 100 that performs digital processing and data manipulation during the calibration procedure. The digital core may be the heart of the current sensor package 100, responsible for executing instructions and performing the computational tasks required for the calibration procedure. It may include a control unit, an arithmetic logic unit (ALU), memory, and input / output (I / O) interfaces, depending on the specific application and design. The digital processor 112 may include or interface with a non-volatile memory 114. The non-volatile memory 114 may be implemented as an EEPROM, which can be electrically programmed and erased during the calibration procedure.

[0046] Those skilled in the art, taking advantage of the present disclosure, will recognize that the current sensor package 100 may include more circuit components than in Fig. 1. For example, a power supply circuit may provide the necessary power for operating the current sensor package 100. It may include voltage regulators, decoupling capacitors, and other components to ensure stable and reliable operation. An output circuit may provide the output signal of the current sensor package 100, which may be in the form of a voltage or current signal proportional to the input current. The output circuit may include voltage dividers, buffer amplifiers, and other components to provide a stable and reliable output signal.

[0047] The integrated current sensor circuit 102, the ADC 108, the digital processor 112, and the non-volatile memory 114 can all be integrated on a common semiconductor die. Thus, the current sensor package 100 can comprise a single semiconductor die that integrates the current sensor circuit 112, the ADC 108, the digital processor 112, and the non-volatile memory 114. In such a case, the current sensor package 100 can also be referred to as a current sensor IC 100.

[0048] The digital processor 112 in the current sensor package 100 may include a memory that stores program code to execute the self-calibration procedure of the current sensor package 100 when the program code is executed on the digital processor 112. The digital processor 112 may be configured to start the integrated calibration procedure when at least one terminal or pin 116 of the current sensor package is set to a predefined state for a predefined time. The predefined state may correspond to a predefined voltage, such as ground (GND) or a power supply voltage (VDD). The predefined time may correspond to, for example, 1 s, 2 s, or 5 s.

[0049] The digital processor 112 in the current sensor package 100 may be configured to determine an offset value of the integrated current sensor circuit 102 during the self-calibration procedure, assuming that no current is present in the power rail 106 within a predefined time window from the start time. As previously mentioned, the offset value may be caused by a variety of factors, including temperature fluctuations, magnetic interference, manufacturing variations, electrical noise, aging and degradation, or mechanical stress.

[0050] Furthermore, during the self-calibration procedure, the digital processor 112 in the current sensor package 100 may be configured to determine a sensitivity value of the integrated current sensor circuit 102 based on a predefined electrical test current through the power rail 106 within a predefined time window from the start time. The sensitivity of the current sensor may be influenced by various factors, including a distance between the current-carrying conductor and the sensor, a frequency of the measured current, an ambient temperature, or electrical noise. The sensitivity value may be calculated based on the predefined electrical test current, the digital sensor signal 110 in response to the predefined electrical test current, and the offset value.

[0051] The proposed current sensor package 100 with built-in self-calibration can automatically correct the sensitivity and offset according to the target sensitivity and target offset required by the system.

[0052] In the case of external power rails 106, a target sensitivity in [V / A] cannot be selected by the user, since a transfer factor TF [T / A] between the external power rail 106 and the one or more sensing elements must be known. A datasheet must specify the nominal TFs to be implemented by the user for each sensor gain [V / T]. This does not pose a problem, but rather reduces the effort on the user side, since they do not have to design the power rail; instead, predefined designs are provided by a sensor manufacturer.

[0053] In case of external busbars 106, the TF [T / A] of the internal busbar is known by design.

[0054] The target sensitivity is then defined and known to the sensor package 100: Target Sensitivity[VA]=TF[TA]∗Sensor Gain[VT]

[0055] The target offset can be zero. The self-calibration procedure can therefore be simplified as follows: 1. Enter the “calibration mode” of the digital processor 112 by pulling down pin 116. 2. The digital processor 112 measures the (digital) sensor offset V O|I=0 (analog sensor signal 104) assuming that no current is present in the power rail 106 within a predefined time window from the start time. 3. Forcing a predefined test current I TEST in the power rail 106 (e.g., <1% error, which is negligible with regard to target accuracy) within a predefined time window from the start time. The value of the test current I TESTcan be specified on the datasheet and is different for each sensor gain setting. 4. The digital processor 112 measures the (digital) output pin voltage V0|lTEST (analog sensor signal 104) and calculates the sensitivity while the target test current I TEST is known Sensitivity=V0|lTEST−V0|l=0lTEST 5. The digital processor 112 calculates a correction factor required to obtain a target sensitivity and a target offset and stores the correction factors in the EEPROM 114. The correction factors can then be combined with actual measured values ​​to generate a calibrated analog sensor signal 104.

[0056] Fig. 2 shows a flowchart of a method 200 for self-calibrating the current sensor package 100 without the need for an external microcontroller.

[0057] The method 200 includes generating 202, using the current sensor circuit 102 integrated into the current sensor package 100, an analog sensor signal 104 in response to an electrical current in an internal or external power rail 106.

[0058] The method 200 further includes converting 204 the analog sensor signal 104 into a digital sensor signal 110 using an ADC 108 integrated into the current sensor package 100. The method 200 further includes performing 206, on the digital core 112 integrated into the current sensor package 100, a self-calibration procedure using the digital sensor signal and predefined target values ​​for offset and sensitivity. The method 200 further includes storing 208 the predefined target values ​​and calibration parameters found during the calibration procedure on the non-volatile memory 114 integrated into the current sensor package 100.

[0059] The self-calibration procedure may be initiated by setting at least one terminal or pin 116 of the current sensor package 100 to a predefined state (e.g., predefined voltage) for a predefined time.

[0060] The self-calibration procedure performed on the digital core 112 may measure an offset value V within a predefined time window after initiating the self-calibration procedure. O|I=0 of the current sensor, assuming that no electrical current is present in the bus bar 106.

[0061] The self-calibration procedure performed on the digital core 112 may force a predefined test current I after the predefined time window from the initiation of the self-calibration procedure. TEST in the busbar 106 and calculating a sensitivity value Sensitivity of the current sensor based on the predefined test current I TEST , the digital sensor signal V0|lTEST responsive to the predefined test current and the offset value V0|lTEST include.

[0062] The self-calibration procedure performed on the digital core 112 may include calculating one or more correction factors required to obtain a target sensitivity and a target offset of the current sensor and storing the one or more correction factors in the non-volatile memory 114.

[0063] An advantage for the user may be that the only requirements for the proposed EOL self-calibration of the current sensor package 100 are to provide an accurate test current I TESTin power rail 106 and trigger sensor calibration mode at an EOL of its system. There is no need to implement a dedicated digital interface in an external microcontroller, since calibration mode can be initiated by pulling a pin low at startup. There is no need to implement the calibration routine in the microcontroller firmware. This is an advantage because it minimizes the effort required in developing the microcontroller firmware and in modifying the firmware for existing systems.

[0064] The aspects and features described in connection with a particular one of the previous examples may also be combined with one or more of the further examples to replace an identical or similar feature of that further example or to additionally introduce the feature into the further example.

[0065] Examples may further be or relate to a (computer) program comprising program code for carrying out one or more of the foregoing methods, when the program is executed on a computer, a processor, or other programmable hardware component. Steps, operations, or processes of various of the methods described above may therefore also be carried out by programmed computers, processors, or other programmable hardware components. Examples may also cover program storage devices, e.g., digital data storage media, that are machine-, processor-, or computer-readable and encode and / or include machine-executable, processor-executable, or computer-executable programs and instructions. The program storage devices may, for example,digital storage devices, magnetic storage media, such as magnetic disks and magnetic tapes, hard disk drives, or optically readable digital data storage media. Further examples may also include computers, processors, control units, (field-)programmable logic arrays ((F)PLAs; (field) programmable logic arrays)), (field) programmable gate arrays ((F)PGAs; (field) programmable gate arrays)), graphics processor units (GPUs), application-specific integrated circuits (ASICs), integrated circuits (ICs), or system-on-a-chip (SoCs; system-on-a-chip) systems programmed to carry out the steps of the methods described above.

[0066] It is further understood that the disclosure of multiple steps, processes, operations, or functions disclosed in the specification or claims should not be construed as necessarily being in the described order, unless explicitly stated in the individual case or required for technical reasons. Therefore, the foregoing description does not limit the performance of multiple steps or functions to any particular order. Furthermore, in further examples, a single step, function, process, or operation may include and / or be broken down into multiple sub-steps, functions, processes, or operations.

[0067] If some aspects are described in connection with a device or system, these aspects are also to be understood as a description of the corresponding method. For example, a block, device, or functional aspect of the device or system can correspond to a feature, such as a method step, of the corresponding method. Accordingly, aspects described in connection with a method are also to be understood as a description of a corresponding block, element, property, or functional feature of a corresponding device or system.

[0068] The following claims are hereby incorporated into the Detailed Description, and each claim may stand on its own as a separate example. It should also be noted that although a dependent claim in the claims refers to a particular combination with one or more other claims, other examples may include a combination of the dependent claim with the subject matter of any other dependent or independent claim. Such combinations are hereby explicitly contemplated unless it is specifically stated that a particular combination is not intended. Furthermore, features of a claim for any other independent claim are also intended to be encompassed, even if that claim is not directly defined as dependent on that other independent claim.

Claims

[1] A current sensor package (100) comprising an integrated current sensor circuit (102) configured to generate an analog sensor signal (104) in response to an electrical current; an analog-to-digital converter, ADC (108) coupled to the integrated current sensor circuit (102) and configured to convert the analog sensor signal (104) into a digital sensor signal (110); a digital processor (112) coupled to the ADC (108) and configured to perform a calibration procedure for the integrated current sensor circuit (102) based on the digital sensor signal (110) and predefined target values; a non-volatile memory (114) coupled to the digital processor (112) and configured to store the predefined target values ​​and calibration parameters found during the calibration procedure. [2] The current sensor package (100) of claim 1, wherein the integrated current sensor circuit (102) comprises a sensing element and signal conditioning circuitry configured to process an analog output signal from the sensing element. [3] The current sensor package (100) of claim 1 or 2, wherein the integrated current sensor circuit (102) comprises a coil, a magnetoresistive device, or a Hall effect sensor. [4] The current sensor package (100) according to any one of the preceding claims, wherein the digital processor (112) is configured to start the calibration procedure when at least one terminal of the current sensor package is set to a predefined state for a predefined time. [5] The current sensor package (100) according to any one of the preceding claims, wherein the digital processor (112) is configured to determine, during the calibration procedure, an offset value of the integrated current sensor circuit (102), and a sensitivity value of the integrated current sensor circuit (102) based on a predefined electrical current, the digital sensor signal responsive to the predefined electrical current, and the offset value. [6] The current sensor package (100) of claim 5, wherein the non-volatile memory (114) is configured to store one or more correction factors required to obtain a target sensitivity and a target offset of the integrated current sensor circuit (102). [7] The current sensor package (100) according to any one of the preceding claims, wherein the integrated current sensor circuit (102), the ADC (108), the digital processor (112) and the non-volatile memory (114) are integrated on a common semiconductor substrate. [8] The current sensor package (100) according to any one of the preceding claims, wherein the non-volatile memory (114) comprises an EEPROM. [9] The current sensor package (100) according to any one of the preceding claims, further comprising a bus bar (106) integrated into the current sensor package. [10] A method (200) for calibrating a current sensor package (100), the method comprising Generating (202), using a current sensor circuit (102) integrated into the current sensor package, an analog sensor signal (104) in response to an electrical current; Converting (204) the analog sensor signal (104) into a digital sensor signal (110) using an ADC (108) integrated into the current sensor package; Performing (206), on a digital processor (112) integrated into the current sensor package, a calibration procedure for the integrated current sensor circuit (102) based on the digital sensor signal (110) and predefined target values; Storing (208) the predefined target values ​​and calibration parameters found during the calibration procedure on a non-volatile memory (114) integrated into the current sensor package. [11] The method (200) of claim 10, further comprising initiating the calibration procedure by setting at least one terminal (116) of the current sensor package (100) to a predefined state for a predefined time. [12] The method (200) according to claim 10 or 11, comprising performing (206) the calibration procedure comprising, within a predefined time window from initiating the calibration procedure, measuring an offset value of the integrated current sensor circuit (102) assuming that no electrical current is present in a measurement path (106). [13] The method (200) according to claim 12, comprising performing (206) the calibration procedure after the predefined time window from the initiation of the calibration procedure, forcing a predefined test current in the measurement path (106), and Calculating a sensitivity value of the integrated current sensor circuit (102) based on the predefined test current, the digital sensor signal (110) responsive to the predefined test current, and the offset value. [14] The method (200) according to claim 13, comprising performing (206) the calibration procedure Calculating one or more correction factors required to obtain a target sensitivity and a target offset of the integrated current sensor circuit, and Storing the one or more correction factors in the non-volatile memory (114).

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