Sensor chip and its associated lead frame used for calibration

Abstract

This disclosure describes a sensor chip for calibration and its associated lead frame. The present disclosure relates to a packaged sensor chip (100) having: a lead frame (20) on which a sensor element (10) is mounted, designed to generate a sensor signal dependent on a magnetic field experienced by the sensor element; and a housing (30) for this purpose. The lead frame has functional terminals (40) having at least two calibration terminals (T1, T2, COM) arranged on opposite sides of the housing. The lead frame has a conductive structure (60) connecting the at least two calibration terminals, the conductive structure being configured to generate a calibration magnetic field for the sensor element when current flows through it. The conductive structure is part of a connection structure (50, 60) connecting the multiple lead frames before they separate from each other along a first direction (the other two opposite sides are opposite each other along the first direction).

Description

Technical Field

[0001] This disclosure relates to a packaged sensor chip, a lead frame structure for packaging the sensor chip, and a method for manufacturing such a sensor chip. Background Technology

[0002] Developing and manufacturing inexpensive yet accurate magnetic field sensors remains a major challenge. Currently, integrated magnetic field sensors require expensive calibration and testing equipment, and because they are not standardized, they must be developed individually for each product. In particular, angle or 3D sensors used for magnetic fields require sophisticated angle or 3D calibration equipment for calibration.

[0003] For Hall sensors, a so-called WOC (Wire-on-Chip) was developed, in which additional wires surrounding the Hall sensor element, arranged vertically or laterally, generate a magnetic field when an excitation current is applied. This generates a localized magnetic field, which can be used to calibrate and adjust the sensor. The WOC principle is based on a method of measuring the difference between two magnetic fields induced by two electrical conductors, where current is applied to each of the two copper contact surfaces—so-called chips (these two surfaces forming the two ends of the electrical conductors)—for an excitation test that generates a specific magnetic field.

[0004] Another concept, the so-called BWOC (Backside Wire on Chip), involves depositing conductive lines on the back side of a chip to generate the desired magnetic field, which can be used to adjust or calibrate a magnetic field sensor. This concept can be used in any lateral measurement system, such as giant magnetoresistance (GMR) or anisotropic magnetoresistance (AMR). With special arrangements, even vertically sensitive devices such as Hall plates can be used. When current flows through the BWOC, a magnetic field is generated. By properly placing the BWOC below or along the Hall region, the magnetic field can optimally penetrate the sensor vertically and can be measured. A large current must flow through the BWOC to achieve the desired field density on the sensor surface. The wire must be large enough to carry the required amount of current. The required amount of current depends on the distance between the conductive wire and the sensor surface. Summary of the Invention

[0005] The aim is to provide a sensor chip that is simple and inexpensive to manufacture, while improving the reliability of measurements performed with it compared to conventional sensors or sensor chips.

[0006] As an example of solving this problem, the packaged sensor chip has the following features: a sensor element designed to generate a sensor signal that depends on a magnetic field experienced by the sensor element; a lead frame on which the sensor element is mounted; and a housing that encapsulates the sensor element and the lead frame, wherein the lead frame has functional terminals arranged on at least one of two opposite sides of the housing, wherein the lead frame has at least two calibration terminals arranged on the other two opposite sides of the housing, wherein the lead frame has a conductive structure connecting the at least two calibration terminals, wherein the conductive structure is configured to generate a calibration magnetic field for the sensor element when current flows through it, and wherein the conductive structure is part of a connection structure that connects the multiple lead frames before they separate from each other along a first direction (the other two opposite sides are opposite each other along this direction).

[0007] In other words, the general concept of this disclosure is to use a lead frame as a source of magnetic field to calibrate a magnetically sensitive sensor element. When using a conductive structure that is part of the lead frame, there is no need to provide separate wires for generating a magnetic field to produce a predetermined current, i.e., these additional components can be saved. Another advantage arising from this is that the distance from the conductive structure that generates the guiding current for the magnetic field required for calibration to the sensor can be advantageously reduced. Therefore, a sensor chip packaged with a lead frame according to this disclosure can be made flatter. Since the distance between the conductive structure that guides the current and the sensor element to be calibrated is small, the magnitude of the predetermined current used to generate the magnetic field, which is necessary for calibrating the sensor element, can also be minimized. This means that, according to the concept of this disclosure, the current level used for calibrating the sensor element can be significantly reduced in the case of a sensor chip compared to conventional sensor chips. In the sense of this disclosure, opposite sides should also be understood as mutually exclusive sides of the same sensor chip or lead frame.

[0008] Another aspect of this disclosure relates to a lead frame structure having the following features: a plurality of lead frames, each designed to manufacture a sensor chip according to the aforementioned package; a plurality of connection plates, wherein at least one connection plate is disposed between each pair of adjacent lead frames along a first direction; wherein the connection structure has a conductive structure and connection plates, and wherein the connection plates are designed to be cut off upon separation of the lead frames, such that the remaining plate ends after separation form calibration terminals. In this case, it is particularly advantageous that the connection structure having the conductive structure and connection plates performs a variety of functions, for example, that can be used during the manufacture of the sensor chip. On the one hand, the respective connection plates connect adjacent lead frames, wherein these connection plates ensure a mechanically stable connection between the respective lead frames; on the other hand, the sensor chip can be calibrated through the same connection plates. Furthermore, after the respective sensor chip is separated, the connection plate continues to function as a calibration terminal, through which a predetermined calibration current for setting the sensor element of the sensor chip can be introduced into or pass through the conductive structure.

[0009] Another aspect of this disclosure relates to a method for manufacturing a plurality of packaged sensor chips, characterized by: providing a lead frame structure according to one of the following examples; mounting at least one sensor element onto a corresponding lead frame; encapsulating the corresponding sensor element and the lead frame into a packaged sensor chip; separating the packaged sensor chip from the lead frame structure; wherein the method includes calibration by applying current to at least some calibration terminals before and / or after separating the sensor chips. As described above, the lead frame structure provided according to this disclosure allows, on the one hand, respective connecting plates to connect adjacent lead frames, wherein the connecting plates ensure mechanically stable connections between the respective lead frames, and on the other hand, the sensor chip can be calibrated through the same connecting plates. Furthermore, after separating the corresponding sensor chips, the connecting plates continue to perform the function of calibration terminals, through which a predetermined calibration current for setting the sensor element of the sensor chip can be introduced into or pass through a conductive structure. Attached Figure Description

[0010] Some examples are schematically depicted in the accompanying drawings and explained below. They are shown here:

[0011] Figure 1 It is a top view projection based on the example sensor chip with a lead frame.

[0012] Figure 2 It is based on Figure 1 The example is a side view projection of the sensor chip with a lead frame.

[0013] Figure 3 yes Figure 2 The sensor chip in the image is rotated 90° in a side view projection, and the sensor chip has a... Figure 1 Example leader box,

[0014] Figure 4 It is a lead frame structure with multiple lead frames that can be held together and aligned by multiple connecting plates according to a connection structure of an advantageous example. Detailed Implementation

[0015] Figure 1 A top view projection of a sensor chip 100 with a lead frame 20 is shown as an example. The sensor chip 100 has a square housing 30 in the top view. According to another example, the housing 30 may have a polygonal or elliptical shape. Figure 1 In the diagram, functional terminals 40 are shown on two opposite sides or opposite sides of the housing 30, and calibration terminals T1, T2, and COM are shown on two other opposite sides or opposite sides of the housing 30, as part of the lead frame 20. Figure 1 In the current example, certain calibration terminals 50 are also identified by reference numerals T1, T2, and COM, respectively. The lead frame 20 has a conductive structure 60 that connects the calibration terminals T1, T2, and COM to each other. The purpose of the conductive structure 60 is to generate a calibration magnetic field for the sensor element 10 when current flows through it. The sensor element 10 is further designed to generate a sensor signal that depends on the magnetic field experienced by the sensor element 10. The sensor element 10 can be, for example, any magnetically sensitive element such as a magnetoresistive sensor, a Hall sensor, an inductive sensor such as a classical induction coil, etc. Other examples involve XMR (X-magnetoresistive) sensors, such as spin-orbit torque or vortex structures.

[0016] The characteristics and advantages of the features listed in the examples below also apply to packaged sensor chips, the lead frame structure of packaged sensor chips, and methods for manufacturing multiple packaged sensor chips using the lead frame structure. The features can be combined with each other.

[0017] In advantageous embodiments of this disclosure, the sensor element is electrically connected to at least a portion of a plurality of functional terminals. The functional terminals of the sensor chip represent connections or terminals to the outside world, through which sensor signals generated by the sensor element can be forwarded or provided to other electrical devices. For example, this could be additional measuring and / or control devices that initiate predetermined method steps based on signals received from the sensor element of the sensor chip.

[0018] Suitablely, the conductive structure and / or its associated calibration terminals are electrically isolated from the functional terminals. Electrical isolation is particularly important if the permissible current or voltage transmitted or applied through the calibration terminals or functional terminals have different permissible thresholds. Furthermore, according to advantageous examples, the separation of dedicated functions is particularly advantageous when certain portions of the circuitry with the leadframe are no longer in use, as this allows the sensor chip to be operated as a whole in an energy-efficient manner.

[0019] In one example, at least two conductive structures and their respective calibration terminals are electrically isolated from each other. This isolation is particularly useful if different currents for different purposes are conducted via the calibration terminals of the respective conductive structures. Based on this, the corresponding conductive structures can be sized differently according to specific needs, with respect to predetermined physical characteristics. For example, when calibrating different sensor elements, electrical isolation can also be used to avoid affecting individual or corresponding conductive structures.

[0020] In one example, at least one conductor of the conductive structure extends in a straight line along a first direction, and / or at least one conductor of the conductive structure extends perpendicular to the first direction. The shortest connection between the calibration terminals corresponds to the straight extension of the conductive structure along the first direction. Short connections are energy-efficient and save materials. By arranging at least one additional conductor of the conductive structure perpendicular to the first direction and / or perpendicular to the straight extension of the conductive structure in the first direction, for example, two mutually perpendicular magnetic fields can be generated when a predetermined current flows through the conductive structure. The correspondingly generated magnetic fields can be used to calibrate sensor elements, such as magnetic sensors in sensor chips. In addition, different currents matched to the various sensor elements of the sensor chip (and, for example, currents used to calibrate the sensor elements) can flow through the various wires of the conductive structure. Furthermore, at least two conductive structures can also have the same or parallel extension directions, which can thus also be used to check the reasonableness of the measured values ​​when calibrating one or more sensor elements.

[0021] In another example, the sensor element has a magnetic sensor. The arrangement of two mutually perpendicular conductors in the conductive structure described above is particularly suitable for calibrating the magnetic sensor by means of multiple generated magnetic fields. One such example is a 2D sensor, in which predetermined magnetic fields can be generated independently of each other in predetermined erroneous configurations. In this way, the two conductors of the conductive structure can be measured independently of each other.

[0022] In another example, the magnetic sensor incorporates a Hall sensor and / or an XMR sensor and / or an inductive sensor. The Hall sensor and / or XMR sensor can be designed to be particularly small and space-saving, and these sensors are capable of measuring magnetic fields of different directions and intensities. Hall sensors are particularly well-suited for detecting position within magnetic fields; that is, Hall sensors are especially suitable for detecting magnetic fields of different directions.

[0023] In yet another example, the sensor chip has at least one additional sensor element designed to detect the state of the environment in which the sensor chip exists. If the calibration of the sensor element by means of the sensor element depends on another physical variable, then the additional sensor element is suitable, for example, as it can be detected by means of the additional sensor element. By taking into account the individual (and sometimes mutual) effects of different physical variables, the sensor element can be calibrated with particular accuracy and reliability.

[0024] Another sensor element advantageously includes a temperature sensor. For example, the values ​​recorded by means of a magnetic sensor depend to a large extent on the ambient temperature or the temperature of the magnetic sensor itself. Therefore, when calibrating a magnetic sensor, it is recommended to take temperature or its effects into account during calibration.

[0025] To minimize the mutual interference between individual sensor elements or their corresponding conductive conductors, additional sensor elements have conductive structures and associated calibration terminals that are electrically isolated from the conductive structures and calibration terminals of the sensor elements. This electrical isolation allows for the alternating application of current to the conductors of the conductive structures associated with the respective sensor elements, or the simultaneous application of the same current or different currents. Therefore, the flexibility of calibrating or using sensor elements or sensor chips can be increased.

[0026] Suitablely, the remaining plate ends of the connecting structure or lead frame structure after separation are molded onto the housing in a form-fit and / or force-fit manner. This ensures that the plate ends do not interfere with the processing of the sensor chip.

[0027] In another suitable example, the remaining plate end after separation is designed to be used as a calibration terminal. Thus, whether the plate end is in the state of being molded onto the housing, or the plate end is bent while it is being used as a calibration terminal and then remolded onto the housing after calibrating the sensor element of the sensor chip, the plate end can continue to be used as a calibration terminal for the sensor chip.

[0028] A particular advantage of the method for manufacturing multiple packaged sensor chips with the above-described features is that, after separating the sensor chips, at least one sensor element is calibrated or can be calibrated. Therefore, after separating the respective sensor chips, the calibration already performed can be checked, or the sensor element can be trimmed or calibrated even more precisely. Thus, each sensor chip can be specifically matched to the particular needs of its application.

[0029] With such a system, sensitive sensors can be easily tested on the back end without the need for special magnetic units. This reduces testing time and equipment costs, thereby lowering the overall cost of the sensor chip. Combined with the (back-end film on-line) BWOC system, magnetic sensors can be tested on both the front and back ends of production. The sensor chip can even be used during its application for later calibration.

[0030] This concept can be advantageously applied to SMD (surface mount device) assemblies that, due to manufacturing process limitations, must be measured individually; for example, in cases where functional and / or calibration terminals are bent before molding, as this would otherwise introduce voltage into the housing. Such a load can cause sensitivity fluctuations in the sensor chip or sensor element. After the sensor chip is manufactured, calibration terminals can be bent or molded along the package to form additional contact pads for later and / or additional calibration. Using specialized probes, these contact pads can be used to conduct current through the conductive structure of the sensor chip's connection structure.

[0031] The concept described above for sensor chip calibration can also be applied to tape measure measuring devices. Utilizing the special geometry of the lead frame, the calibration terminals can be extended to allow connection to a key pin or probe pin.

[0032] Some examples offer the potential to significantly reduce the production cost of magnetic field sensors, especially those that utilize correlated or differential fields, such as angularly robust, stray-field robust current sensors. It is even possible to generate electromagnetic pulses to simulate the gears of a speed sensor.

[0033] In the foregoing description, various features are combined in the examples to justify this disclosure. This type of disclosure should not be construed as an intention that the claimed example has more features than those expressly stated in each claim. Rather, as reflected in the appended claims, the subject matter may be less than all the features of a single disclosed example. Therefore, the following claims are thus incorporated into the detailed description, wherein each claim is taken independently as a separate example. While each claim may be taken as its own separate example, it should be noted that, despite specific combinations of dependent claims with one or more other claims, other examples will also combine the subject matter of dependent claims with the subject matter of claims that are independent of each other. Or each feature may be combined with other dependent or independent claims. Such combinations are included unless otherwise specified. It is also intended that combinations of features of the claims be included together with any other independent claim, even if that claim does not directly depend on the independent claim.

[0034] In the following description, examples of this disclosure are illustrated in detail using the accompanying description. It should be noted that identical elements or elements having the same function may be provided with the same or similar reference numerals, and repeated descriptions of elements having the same or similar reference numerals are generally omitted. The descriptions of elements having the same or similar reference numerals are interchangeable. Numerous details are described in the following description to provide a more thorough explanation of the examples of this disclosure. However, it will be apparent to those skilled in the art that other examples can be implemented without these specific details. Features of the different examples described may be combined with each other unless the features of the corresponding combinations are mutually exclusive or explicitly exclude such combinations. Method steps relating to a particular feature of the device may be interchanged with that feature of the device, and vice versa.

[0035] exist Figure 1 An example of a 2D sensor is shown, in which X and Y magnetic fields can be generated in two different directions, for example, independently of each other. For instance, the magnetic field generated in the X direction and the magnetic field generated in the Y direction are perpendicular to each other. The magnetic fields generated in different directions can have different intensities. According to... Figure 1 For example, by applying a current flowing from calibration terminal T1 or T2 to calibration terminal COM, calibration magnetic fields perpendicular to each other can be generated respectively. In the example shown, a single conductor T2-COM extends in a straight line from T2 to COM in the first direction (between the shortest distances between the two opposite sides) of the lead frame 20 of the sensor chip 100. This saves material and minimizes losses based on the resistance present in the material of conductor T2-COM. Another conductor T1-COM, which leads from calibration terminal T1 to calibration terminal COM, is... Figure 1 In this example, the two conductors T1-COM and T2-COM are connected to each other electrically. In order to generate the calibration magnetic field required for sensor element 10, in this example, the corresponding current flows through each conductor T1-COM and T2-COM in turn.

[0036] In order to enable the generation of two or more calibration magnetic fields independently of each other and to be measured or detected by sensor element 10, according to another advantageous embodiment, the individual conductors T1-COM, T2-COM can be electrically isolated from each other. Due to the electrical isolation, the different dimensions of the individual conductors T1-COM, T2-COM can be matched with a predetermined current to generate the calibration magnetic field. In another advantageous example, the individual functional terminals 40 are also electrically isolated from the conductive structure 60 and / or its associated calibration terminals T1, T2, COM. Electrical isolation can prevent functional errors of the sensor chip 100 due to incorrect wiring.

[0037] According to Figure 1In this example, sensor element 10 is embedded in / on wafer 70. Sensor element 10 is advantageously arranged near or adjacent to conductive structure 60, which generates the calibration magnetic field. This is desirable because the current generating the calibration magnetic field must be selected based on a predetermined distance between sensor element 10 and conductive structure 60. The strength of the calibration magnetic field decreases proportionally with the distance from the conductor generating the calibration magnetic field. Additionally, the permeability of the material that can be arranged between conductive structure 60 and sensor element 10, such as the permeability of the material of wafer 70, must also be considered. To achieve the required field density for sensor element 10, a large current must flow through conductive structure 60 of lead frame 20. Furthermore, the thickness of wafer 70 also significantly affects the required current. If wafer 70 can be thinned, for example, to 35 μm, as is the case in this example, the amount of current required to generate the calibration magnetic field decreases dramatically. As a result, the influence of the current flowing through the conductive structure on other conductive structures of sensor chip 100 (not shown here) can also be reduced.

[0038] According to another example, sensor chip 100 may have at least one additional sensor element (not shown). Suitably, the additional sensor element is designed to detect the state of the environment in which sensor chip 100 is located. Advantageously, the additional sensor element is configured as a temperature sensor. This is particularly advantageous when sensor element 10 of sensor chip 100 has a magnetic sensor. Magnetic sensors react differently to temperature changes. By means of another sensor element configured as a temperature sensor, the measurements of the magnetic sensor can be detected more accurately and / or checked in terms of reasonableness.

[0039] Because a large current flows through lead frame 20 to generate a magnetic field or calibration magnetic field, this allows for further improvements in calibration when taking temperature into account, without requiring additional calibration terminals beyond the already provided calibration terminals T1, T2, COM or conductors T1-COM, T2- of the conductive structure 60. This is because the current also generates heat loss and heat during the current excitation used to generate the calibration magnetic field. During calibration, the temperature can rise steadily. According to a suitable example, various measurements, including temperature, for the magnetic field or calibration magnetic field can be performed in one or more identical test inserts.

[0040] In this way, different combinations of calibration of the sensor chip 100 can be performed. The various conductors T1-COM, T2-COM of the conductive structure 60 and their corresponding calibration terminals T1, T2, COM can be used to calibrate the same and / or different sensor elements 10.

[0041] Figure 2 The image shows a projection of a side view of a sensor chip 100, which has according to... Figure 1Example lead frame 20. Here the arrangement of the various elements forming the sensor chip 100 can be seen. Functional terminals 40 are used to control the sensor chip 100 or serve as terminals for providing the detected or measured sensor signal to the sensor element 10. They form part of the lead frame 20 together with the conductive structure 60, which has calibration terminals T1, T2, COM connected thereto. Wafer 70 is arranged parallel to the plane of the conductive structure 60, in or above which the sensor element 10 is embedded. The wafer 70 shown can be made particularly thin and has a thickness similar to or the same as that of the conductive structure 60. As shown above... Figure 1 As already discussed, it is particularly advantageous that the spacing between the sensor element 10 and the conductors T1-COM and T2-COM that generate the calibration magnetic field is small. This allows for a smaller selection of the current entering the conductive structure 60 through the calibration terminals T1, T2, COM for generating the calibration magnetic field. This also reduces losses due to heat dissipation determined by the resistance of the conductive structure 60, and subjects the entire lead frame 20 and sensor chip 100 to a lower load. By reducing heat dissipation, the sensor signal of the sensor element 10 can also be reliably detected (independent of thermal effects).

[0042] Figure 2 The example described illustrates a sensor chip 100 in an SMD (Surface-mounted device) embodiment. Various calibration terminals T1, T2, COM are molded onto the surface of the housing 30 of the sensor chip 100. In an advantageous example, even after the respective sensor chip 100 has been separated from the lead frame structure 200 comprising multiple lead frames 20, the calibration terminals T1, T2, COM can continue to function as calibration terminals T1, T2, COM, where these calibration terminals provide surfaces that can be contacted by measuring needles or probes. To ensure reliable function during the calibration of the sensor chip 100, the calibration terminals T1, T2, COM are molded onto the housing 30 in a form-fit and / or force-fit manner. Upon request, the calibration terminals T1, T2, COM molded onto the housing 30 of the sensor chip 100 can also be bent outwards from the housing 30 and then bent back again.

[0043] Figure 3 yes Figure 2 The sensor chip in the image is rotated 90° in a side view projection, and the sensor chip has a... Figure 1 or Figure 2 The example leader box 20. Specifically, in Figure 3The bending structure of the functional terminals 40 exposed from the housing 30 of the sensor chip 100 on the side can be identified. The physical properties of the functional terminals 40 can be altered by bending—this includes altering them until the sensor chip 100 becomes unusable. Therefore, the functional terminals 40 will also be unsuitable for calibrating the sensor element 10 of the sensor chip 100, as accurate calibration of the sensor element 10 cannot be guaranteed without problems. Therefore, dedicated calibration terminals T1, T2, and COM are provided in the example of the sensor chip 100 to reliably perform calibration of the sensor element 10; and this is also done after the sensor chip 100 is manufactured, where the calibration terminals T1, T2, and COM, molded on the housing 30 of the sensor chip 100, can be used.

[0044] The illustrations of the sensor chip 100 with sensor element 10 explained in this specification should be understood as representative examples only. According to the concept of the drawings, different combinations of two or more sensor elements (not shown) can be of the same or different types. The examples shown can be fabricated and calibrated.

[0045] Figure 4 A lead frame structure 200 with multiple lead frames 20 is described, which can be held together and aligned by multiple connecting plates 50 according to a connection structure of an advantageous example.

[0046] In the example shown, multiple individual lead frames 20 are connected to form a strip-like or coil-like lead frame structure 200, wherein the individual lead frames 20 can be used to fabricate a packaged sensor chip 100 accordingly, for example, in the previous Figures 1 to 3 As described in the text. Each lead frame 20 has multiple connecting plates 50, wherein at least one connecting plate 50 is disposed between each pair of adjacent lead frames 20 of the lead frame structure 200. The connecting plates 50 are arranged between two opposite sides of two adjacent lead frames 20, and these connecting plates have or form corresponding calibration terminals T1, T2, and COM, thereby giving the connection structure of each lead frame 20 a conductive structure 60 and a connecting plate 50. Here, the connecting plate 50 is designed to be cut when the lead frames 20 of the sensor chip 100 are separated, such that the remaining plate ends after separation form calibration terminals T1, T2, and COM. Figure 4 In the example shown, the respective lead frames 20 are connected to each other via three connecting plates 50 to form a lead frame structure 200. Here, each lead frame 20 has a sensor element 10, such as a magnetic sensor, embedded on or within the wafer 70. Depending on the example not shown here, the number of connecting plates 50 or the number of sensor elements 10 in the respective lead frame structure can vary.

[0047] The concept of the lead frame structure 200 is illustrated in a highly simplified manner below, incorporating some method steps for manufacturing and / or calibrating a multi-package sensor chip 100.

[0048] exist Figure 4 Part A shows one state of the lead frame structure 200 in which multiple packages of sensor chips 100 are present before individual sensor chips 100 are separated or disconnected. The individual lead frames 20 are still connected to each other via the connecting plate 50, such that the multiple lead frames 20 of the lead frame structure 200 have the shape of lead frame strips or lead frame reels.

[0049] exist Figure 4 Part B shows one state of the lead frame structure 200 in which the individual lead frames 20 or finished sensor chips 100 are held together only by connection plates 50, wherein two of the three connection plates 50 are separated, and they respectively form calibration terminals T1, T2, and COM of one of the sensor chips 100 or lead frames 20. In this example, the individual sensor elements 10 of the sensor chip 100 can be calibrated via key pins or probes that can be applied to the respective calibration terminals.

[0050] Based on the concepts explained above, in the case of a measuring tape device, a lead frame structure 200 formed using a lead frame 20 can also be used. For example, the lead frame 20... Figures 1 to 3 The special geometry allows for the design or customization of corresponding calibration terminals T1, T2, COM for each lead frame 20, enabling them to connect to the button pins. Figure 4 A portion of the lead frame structure 200 is shown, which is configured as a lead frame strip or strip and provides possible contact points, these contact points in Figure 4 The center is marked as point x, or it provides calibration terminals T1, T2, COM for the key pins.

[0051] According to yet another example, after separation (i.e., the lead frames 20 of the lead frame structure 200 finally separate from each other), the completed sensor chip 100 can continue to be individually calibrated by applying current to at least some of the calibration terminals T1, T2, and COM. According to other examples not shown here, a portion of the calibration can be performed in the state according to section A, while additional calibration steps, such as checks, can be performed in the state according to section B and / or in the calibration steps in the separated state of the sensor chip 100 – see reference. Figures 1 to 3 This allows for a high degree of flexibility in the manufacture or calibration of the sensor element 10 or sensor chip 100 according to the example above.

[0052] The above examples are merely schematic illustrations of the present idea, and it should be understood that modifications and variations of the arrangements and details described herein will be apparent to those skilled in the art. Therefore, it is intended that the idea be limited only by the scope of the appended claims, and not by the specific details presented in conjunction with the description and illustrations herein.

[0053] List of reference numerals

[0054] 100 sensor chips

[0055] 200 lead frame structure

[0056] 10 Sensor Components

[0057] 20 Lead Frame

[0058] 30 Casing

[0059] 40 Functional Terminals

[0060] 50 Connector board (becomes a calibration terminal after the sensor chip is separated)

[0061] 60 Conductive Structure

[0062] 70 chips

[0063] COM calibration terminal

[0064] T1 calibration terminal

[0065] T2 calibration terminal

[0066] T1-COM conductive structure conductor

[0067] T2-COM conductive structure conductor

Claims

1. A packaged sensor chip (100) having the following features: a sensor element (10) designed to generate a sensor signal that depends on a magnetic field experienced by the sensor element (10); a leadframe on which the sensor element (10) is mounted; and a housing (30) that encapsulates the sensor element (10) and the leadframe, wherein the leadframe having functional terminals (40) arranged on at least one of two opposite sides of the housing (30), wherein the leadframe has at least two calibration terminals (Tl, T2, COM) arranged on two further opposite sides of the housing (30), wherein the leadframe has an electrically conductive structure that connects the at least two calibration terminals (Tl, T2, COM), wherein the electrically conductive structure is configured to generate a calibration magnetic field for the sensor element (10) when an electric current flows through the sensor element, and wherein the electrically conductive structure is part of a connection structure that connects a plurality of the leadframes before the plurality of the leadframes is separated from each other in a first direction, wherein the two further opposite sides are opposite in the first direction, wherein the at least one connection plate is designed to be cut off when the leadframe is separated; and wherein plate ends remaining after the separation are form-fittingly and / or force-fittingly molded on the housing (30).

2. The packaged sensor chip (100) according to claim 1, wherein the sensor element (10) is electrically connected to at least a portion of the functional terminals (40).

3. The packaged sensor chip (100) according to claim 1 or 2, wherein the electrically conductive structure and / or the calibration terminals (Tl, T2, COM) to which the electrically conductive structure belongs are electrically isolated from the functional terminals (40).

4. The packaged sensor chip (100) according to claim 1 or 2, wherein at least one conductor of the electrically conductive structure extends linearly in the first direction, and / or at least one conductor of the electrically conductive structure extends perpendicular to the first direction.

5. The packaged sensor chip (100) according to claim 1 or 2, wherein the sensor element (10) has a magnetic sensor.

6. The packaged sensor chip (100) according to claim 5, wherein the magnetic sensor has a Hall sensor and / or an XMR sensor and / or an inductive sensor.

7. The packaged sensor chip (100) according to claim 1 or 2, wherein the sensor chip (100) has at least one further sensor element (10) that is arranged to detect a state of an environment in which the sensor chip (100) is located.

8. The packaged sensor chip (100) according to claim 7, wherein the further sensor element (10) has a temperature sensor.

9. The packaged sensor chip (100) according to claim 7, wherein the further sensor element (10) has an electrically conductive structure and an associated calibration terminal (T1, T2, COM), which electrically conductive structure and calibration terminal are electrically isolated from the electrically conductive structure and calibration terminal of the sensor element (10).

10. A leadframe structure (200) having the following features: a plurality of leadframes, each of the plurality of leadframes being designed to manufacture a packaged sensor chip (100) according to any one of the preceding claims, a plurality of connecting plates, wherein at least one connecting plate is provided between each two leadframes adjacent in the first direction, wherein the connecting structure having the electrically conductive structure and the connecting plates, wherein the connecting plates are designed to be cut off upon separation of the leadframes, such that the plate end portions remaining after the separation form the calibration terminals (T1, T2, COM), and wherein the plate end portions remaining after the separation are configured to be form-fittingly and / or force-fittingly molded on the housing (30).

11. The leadframe structure (200) of claim 10, wherein, The plate end portions remaining after the separation are designed to serve as calibration terminals (T1, T2, COM).

12. A method for manufacturing a plurality of packaged sensor chips (100) having the following features: providing a leadframe structure (200) according to claim 10 or 11; mounting at least one sensor element (10) on a respective leadframe; encapsulating the respective sensor element (10) and the leadframe into a packaged sensor chip (100); separating the packaged sensor chips (100) of the leadframe structure.

13. The method of claim 12, wherein, The method comprises calibrating by applying an electric current to at least some of the calibration terminals (T1, T2, COM) before and / or after separating the sensor chips (100).

14. The method of claim 12 or 13, wherein, Calibrating at least one sensor element (10) after separating the sensor chips (100).

13. The method according to claim 12, wherein the calibration is performed by applying an electric current to at least some of the calibration terminals (T1, T2, COM) before and / or after separating the sensor chips (100).

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