Method for providing an SMD component, and corresponding SMD component
Patent Information
- Application Number
- EP2024703179
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-03-24
- Filing Date
- 2024-02-02
- Publication Date
- 2025-11-19
AI Technical Summary
There is a conflict between achieving precise manufacturing tolerance for low-resistance SMD current measuring resistors to ensure accurate current measurement and maintaining cost-effective production, as high manufacturing precision increases production costs.
A method that produces SMD components with a predetermined nominal value and a specific manufacturing tolerance, followed by a more precise measurement of the component parameter, which is then encoded on the component for later use in a measuring circuit, allowing for cost-effective production and precise measurement without the need for expensive manufacturing processes.
This approach allows for accurate determination and use of the actual component value in measuring circuits, reducing measurement errors and production costs by separating manufacturing and measurement tolerances, enabling precise current measurement while maintaining cost-effectiveness.
Smart Images
Figure EP2024052583_03102024_PF_FP_ABST
Abstract
Description
[0001] DESCRIPTION
[0002] Method for providing an SMD component and corresponding SMD component
[0003] Technical field of the invention
[0004] The invention relates to a method for producing an SMD component (SMD: surface-mounted device), in particular a low-ohm SMD current measuring resistor. Furthermore, the invention relates to a corresponding SMD component.
[0005] Background of the invention
[0006] Low-ohm current measuring resistors, also known as shunts, are known from the prior art (e.g., EP 0 605 800 A1). These resistors are used for current measurement using the four-wire technique. The electrical current to be measured is passed through the low-ohm current measuring resistor, whereby the voltage drop across the low-ohm current measuring resistor is a measure of the electrical current flowing through the current measuring resistor, according to Ohm's law.
[0007] Furthermore, it is known from the prior art to design such low-ohm current measuring resistors as SMD components. When using such an SMD current measuring resistor for current measurement, it is important that the resistance value matches a specified nominal value as closely as possible, i.e., a very precise manufacturing tolerance is desirable to enable precise current measurement. Deviations of the actual resistance value of the SMD current measuring resistor from the specified nominal value lead to a measurement error when calculating the electrical current according to Ohm's law. However, the costs for manufacturing such an SMD current measuring resistor depend on the manufacturing tolerance of the resistance value, i.e., achieving a precise manufacturing tolerance is associated with relatively high manufacturing costs.Thus, in the prior art, there is a conflict of objectives between the desire for the most precise manufacturing tolerance possible with small deviations of the resistance value from the nominal value on the one hand, and the desire for the most cost-effective production possible on the other. Description of the invention.
[0008] The invention is therefore based on the object of resolving the conflict of objectives described above.
[0009] This object is achieved by a method according to the invention or a corresponding SMD component according to the independent claims.
[0010] The method according to the invention initially provides for the production of an SMD component with a predetermined nominal value of a component characteristic of the SMD component and a specific manufacturing tolerance of the component characteristic, as is known per se from the prior art. It should be noted that the invention is not limited to a specific manufacturing method for producing the SMD component.
[0011] In a preferred embodiment of the invention, the SMD component is a low-ohm SMD current measuring resistor. However, the technical teaching of the invention is also fundamentally applicable to other component types, such as capacitors or inductors, to name just two examples.
[0012] In the preferred embodiment of the invention, the nominal value of the SMD component is the specified resistance value, while the manufacturing tolerance defines the permissible fluctuation range of the resistance value around the nominal value. However, the invention is not limited to the resistance value with regard to the nominal value, but can also be implemented with other component parameters. For example, the nominal value of a capacitor can be the capacitance.
[0013] Furthermore, the method according to the invention provides for measuring a measured value of the component characteristic of the SMD component, wherein the measurement is carried out with a specific measuring tolerance depending on the measuring principle used. It is important here that the measuring tolerance is more precise than the manufacturing tolerance. The invention thus combines cost-effective production of the SMD component with an inaccurate manufacturing tolerance with a measurement of the component characteristic with a more precise measuring tolerance. This resolves the conflict of objectives described above between the desire for the most precise manufacturing tolerance possible on the one hand and the desire for a cost-effective manufacturing process on the other. Within the scope of the invention, it is not necessary to use an expensive manufacturing process with a correspondingly precise manufacturing tolerance.Rather, within the scope of the invention, a cost-effective manufacturing process with a correspondingly inaccurate manufacturing tolerance can also be used. The actual value of the component parameter is then determined only during a subsequent measurement with a more precise measurement tolerance.
[0014] Furthermore, the method according to the invention provides that a code is applied to the SMD component, wherein the code contains information about the measured value of the component characteristic of the SMD component and / or about the measurement tolerance. For the sake of clarity, it should be mentioned that when using an SMD current measuring resistor in a measuring circuit, it is not particularly important that the SMD current measuring resistor used adheres to a specific nominal resistance value as precisely as possible. What is more important when using an SMD current measuring resistor in a measuring circuit is that the resistance value is known as precisely as possible with the smallest possible tolerance, since the exact value of the resistance value can then be taken into account in the measuring circuit. For current measurement using the four-wire technique, it is therefore not important that the SMD current measuring resistor used adheres to a specified nominal value as precisely as possible.What's more important is that the measuring circuit knows the actual resistance value of the current measuring resistor used as accurately as possible and can then take this into account when calculating the electrical current flowing through the current measuring resistor according to Ohm's law. For this reason, it's important that the SMD component being measured is provided with a code that reflects the measured value and / or the measurement tolerance. When the SMD component is mounted in an electronic measuring circuit, this code can then be read out, allowing the measured value and / or the measurement tolerance to be subsequently taken into account during operation of the measuring circuit.
[0015] Furthermore, the method according to the invention preferably provides that an electronic circuit (e.g. measuring circuit) is populated with the SMD component according to the invention. The position and / or orientation of the SMD component is preferably detected by means of an optical image processing system, as is known per se from the prior art. The position and / or orientation of the SMD component is then corrected according to the position and / or orientation of the SMD component determined by the image processing system in order to be able to populate the circuit with the SMD component as precisely as possible. After the position and / or orientation of the SMD component has been corrected, the circuit is then populated with the SMD component. The code applied to the SMD component can then be read by the image processing system, which also serves to detect the position and / or orientation of the SMD component during populating the circuit.Therefore, within the scope of the invention, no separate image processing system is required to read the code applied to the SMD component.
[0016] However, within the scope of the invention, it is also possible in principle for a separate image processing system to be provided for reading the code on the SMD component, which image processing system is not used to detect the position and / or orientation of the SMD component when assembling the circuit.
[0017] Furthermore, the method according to the invention preferably provides that the information contained in the read-out code of the SMD component is determined, namely the measured value of the component characteristic and / or the measurement tolerance. This information is then preferably stored in the circuit so that these values can be taken into account during operation of the circuit. For technical explanation, it should be noted that the manufacturing process has a relatively inaccurate manufacturing tolerance, so that the component characteristic can exhibit relatively large fluctuations. It is therefore advisable to store the more precise measured value of the component characteristic in the circuit so that the more precise measured value can be taken into account during operation of the circuit.
[0018] In addition to the inventive method described above, the invention also claims protection for a corresponding SMD component, which is preferably an SMD current measuring resistor. Such SMD components are known per se from the prior art. Furthermore, it is known from the prior art to apply a code to such an SMD component that contains information about a component characteristic of the SMD component. For example, the prior art uses the EIA-96 code (EIA: Electronic Industries Alliance), which is an alphanumeric code. In contrast, the invention provides that the code consists of several geometric symbols that can be distinguished from alphanumeric characters according to the EIA-96 code.
[0019] In a preferred embodiment of the invention, two codes are applied to the SMD component, each consisting of several geometric symbols. For example, the two codes can contain information about different component characteristics of the SMD component.
[0020] In the preferred embodiment of the invention, the geometric symbols of the first code are arranged in a first row, while the geometric symbols of the second code are arranged in a second row on the SMD component. The two rows of the two codes preferably run parallel to each other and can, for example, be aligned transversely or longitudinally to the main current flow direction in the SMD component.
[0021] In addition, a bar may be arranged on the surface of the SMD component to indicate the length of the respective code, wherein the bar may preferably be aligned parallel to the rows of codes and transversely or longitudinally to the main current flow direction in the SMD component.
[0022] With regard to the encoding of information in the code, various possibilities exist within the scope of the invention. For example, the geometric symbols of the code for encoding information can have different colors. Alternatively or additionally, it is possible for the geometric symbols for encoding information to have different brightnesses. Furthermore, it is also possible for the geometric symbols for encoding information to have different shapes. In the simplest case, however, binary encoding is used, with a geometric symbol being present (=1) or missing (=0) at a certain point in the code.
[0023] For example, the geometric symbols can be rectangles, circles, triangles, or hexagons, to name just a few. It's possible for the geometric symbols within a code to be consistent. For example, one code might use triangles as symbols, while another might use rectangles.
[0024] In the preferred embodiment of the invention, the information contained in the code is a component characteristic of the SMD component. For example, the following component characteristics can be included in the code as information:
[0025] • Resistance value,
[0026] • Temperature coefficient of resistance,
[0027] • Size of the SMD component, • Mass of the SM D component,
[0028] • Date of manufacture of the SMD component,
[0029] • Batch number of the SMD component,
[0030] • customer-specific information of the SMD component,
[0031] • Measurement tolerance of the component parameters.
[0032] However, the invention is not limited to the above-mentioned examples with regard to the coded component characteristic.
[0033] In the preferred embodiment of the invention, the SMD component is a low-ohm current measuring resistor with two connection parts made of a conductor material (e.g. copper) for introducing or discharging the electrical current to be measured and a resistance element made of a resistance material (e.g. Manganin®), wherein the resistance element is arranged in the current flow direction between the two connection parts, so that the electrical current to be measured flows through the resistance element.
[0034] The aforementioned code can be applied either to the resistance element or to the connecting parts. Preferably, the current measuring resistor is coated with a protective coating, with the code then preferably applied to the protective coating.
[0035] In general, it should be mentioned that the connecting parts and the resistance element are preferably plate-shaped, whereby either a flat or a curved plate shape is possible.
[0036] Furthermore, it should be mentioned that the current measuring resistor is preferably low-ohmic and has a resistance value of at most 1 Q, 500 mQ, 250 mQ, 100 mQ, 50 mQ, 25 mQ, 10 mQ, 5 mQ, 1 mQ, 500 p , 250 p , 100 p , 50 pQ or 25 pQ.
[0037] The length of the current measuring resistor in the direction of current flow is preferably no more than 5 cm, 2 cm, 1 cm, 5 mm or 3 mm.
[0038] The width of the current measuring resistor transverse to the current flow direction is preferably 5 cm, 2 cm, 1 cm, 5 mm or 3 mm.
[0039] The thickness of the current measuring resistor, however, is preferably no more than 5 mm, 3 mm, 2 mm, or 1 mm. Furthermore, it should also be noted that the code applied to the SMD component is preferably optically readable.
[0040] When using a current measuring resistor, it is also important to note that the conductor material of the connecting parts should have a lower specific electrical resistance than the resistance material of the resistance element.
[0041] For example, the conductor material of the connecting parts can be copper, a copper alloy, aluminum or an aluminum alloy.
[0042] The resistance material, on the other hand, can be, for example, a copper-manganese alloy, an iron-nickel-chromium alloy or a nickel-chromium alloy, to name just a few examples.
[0043] In general, it should also be mentioned that the conductor material of the connecting parts preferably has a specific electrical resistance that is less than 50 10' 8 Q m, 20 10' 8 Q m, 10 10' 8 Q m or 5 10' 8 Q m.
[0044] Finally, it should be mentioned in general that the current measuring resistor preferably has a continuous current strength of at least 1 A, 2 A, 5 A, 10 A, 25 A, 50 A, 100 A or 400 A.
[0045] Other advantageous developments of the invention are characterized in the subclaims or are explained in more detail below together with the description of the preferred embodiment of the invention with reference to the figures.
[0046] Brief description of the drawings
[0047] Figure 1 shows a flow chart to illustrate the method according to the invention.
[0048] Figure 2 shows a diagram to illustrate the relatively coarse manufacturing tolerance and the relatively precise measuring tolerance in a current measuring resistor according to the invention.
[0049] Figure 3 shows a schematic plan view of an SMD current measuring resistor according to the invention. Detailed Description of the Drawings
[0050] In the following, the flow chart according to Figure 1 will first be described, which explains the method according to the invention.
[0051] In a first step S1, an SMD current measuring resistor is first produced, specifically in this embodiment with a nominal value RNENN = 1 mQ of the resistance value R of the SMD current measuring resistor, whereby the manufacturing process has a certain manufacturing tolerance ±AR FERT of the nominal value RNENN. It should be mentioned in advance that the manufacturing tolerance ±AR F ERT can be relatively inaccurate, since the actual value RIST of the resistance value R of the SMD current measuring resistor is measured later. This is advantageous because due to the low requirements for the manufacturing tolerance ±AR F ERT can be used as a cost-effective manufacturing process.
[0052] In a subsequent step S2, a measured value R ESS of the resistance value R of the SMD current measuring resistor with a measurement tolerance ±AR M ESS, with a measurement tolerance of ±AR M ESS is more accurate than the manufacturing tolerance ±AR F ERT, as can also be seen from Fig. 2.
[0053] In a next step S3, a code is then applied to the SMD current measuring resistor, whereby the code contains the measured value RMESS and / or the measuring tolerance ±AR as information. M Contains ESS.
[0054] It should be noted that steps S1-S3 can be carried out by the manufacturer, i.e. by the manufacturer of the SMD current measuring resistor.
[0055] In step S4, the position and orientation of the SMD current measuring resistor is measured in a placement line to assemble a circuit with the SMD current measuring resistor. This measurement of the position and orientation of the SMD current measuring resistor is performed using an image processing system, as is known from conventional placement lines.
[0056] In the next step (S5), the image processing system reads the code on the SMD current measuring resistor. It should be emphasized that the code is read by the image processing system, which is already present in an assembly line to measure the position and orientation of the SMD current measuring resistor. Therefore, no separate image processing system is required to read the code in step S5.
[0057] In step S6, the position and orientation of the SMD current measuring resistor are then corrected according to the position and orientation determined by the image processing system in order to position the SMD current measuring resistor as precisely as possible in the circuit. The circuit is then also assembled with the SMD current measuring resistor in this step.
[0058] In the last step S7, the measured value RMESS of the resistance value R of the SMD current measuring resistor read from the code and the measurement tolerance ±AR M ESS stored in the circuit so that these measured values can be taken into account in the operation of the circuit, in particular for calculating the electrical current flowing through the SMD current measuring resistor as a function of the electrical voltage dropping across the SMD current measuring resistor in accordance with Ohm's law, as explained at the beginning for the well-known four-wire technique.
[0059] Steps S4-S7 are usually carried out by the customer when assembling the circuit.
[0060] In the following, the diagram according to Figure 2 is briefly explained, which shows a relatively large tolerance field 1 of the manufacturing tolerance ±AR F ERT of the resistance value R of the SMD current measuring resistor, while a tolerance field 2 shows the measurement tolerance ±AR MESS shows. This diagram shows that tolerance zone 2 during measurement is significantly smaller than tolerance zone 1 during production of the SMD current measuring resistor. This makes it clear that, within the scope of the invention, a manufacturing process can be used that allows a relatively coarse manufacturing tolerance ±AR F ERT and yet due to the more precise measurement tolerance ±AR M ESS and the small tolerance field 2 during measurement, an accurate determination of the actual resistance value RIST is possible.
[0061] Finally, the top view of an SMD current measuring resistor according to the invention shown in Figure 3 will now be explained.
[0062] The SMD current measuring resistor has a plate-shaped connection part 3 made of a conductor material (e.g., copper) for introducing an electrical current I to be measured into the SMD current measuring resistor. Furthermore, the SMD current measuring resistor has a plate-shaped connection part 4 made of a conductor material (e.g., copper) for diverting the electrical current I to be measured from the SMD current measuring resistor.
[0063] A resistance element 5 made of a resistance alloy (e.g. Manganin®) is arranged between the two connection parts 3, 4, wherein the resistance element 5 is welded at its two edges 6, 7 to the plate-shaped connection parts 3, 4 by electron beam welding.
[0064] Two codes 8, 9 are applied to the surface of the resistance element 5, each of which contains information about a component characteristic of the SMD current measuring resistor.
[0065] Code 8 consists of geometric symbols in the form of triangles 10, while the other code 9 consists of geometric symbols in the form of rectangles 11. The two codes 8 and 9 each have six positions (places) that can be occupied by one of the symbols.
[0066] The information is binary coded by the presence of a symbol at the respective position (=1) or by a gap 12 or 13 (=0).
[0067] The two codes 8, 9 can therefore be 2 S =64 different codewords encode.
[0068] However, it is also possible to vary the color of the symbols. Furthermore, different geometric symbols can be used to encode information. The number of variations V is then calculated as follows:
[0069] V = [ 1 + C - (S - 1) ] P with
[0070] V: Number of possible variations (different codewords),
[0071] C: Number of possible different colors of the geometric symbols,
[0072] S: Number of possible different geometric symbols, where a gap can also be a
[0073] Symbol is,
[0074] P: Number of digits within a code word. Furthermore, the top view also shows a bar 14, which serves two functions. Firstly, bar 14 indicates the length of the two codes 8 and 9. This facilitates the reading of the two codes 8 and 9 by an optical image processing system. Secondly, bar 14 also serves as an alignment aid for aligning the SMD current measuring resistor when fitting the SMD current measuring resistor into the circuit.
[0075] Finally, the top view shows that the SMD current measuring resistor can have a length L along the current flow direction and a width B perpendicular to the current flow direction. The invention is not limited to the preferred embodiment described above. Rather, a multitude of variants and modifications are possible, which also utilize the inventive concept and therefore fall within the scope of protection. In particular, the invention also claims protection for the subject matter and features of the subclaims, independently of the respective claims referred to, and in particular even without the features of the main claim. The invention thus encompasses various aspects of the invention that enjoy protection independently of one another.
[0076] List of reference symbols:
[0077] 1 Tolerance range of the resistance value R during production
[0078] 2 Tolerance field when measuring the resistance value
[0079] 3 Connection part made of a conductor material (e.g. copper) for introducing the electrical current to be measured into the SMD current measuring resistor
[0080] 4 Connection part made of a conductor material (e.g. copper) for conducting the electrical current to be measured from the SMD current measuring resistor
[0081] 5 resistance element made of a resistance material (e.g. Manganin®)
[0082] 6 Edge of the resistance element
[0083] 7 Edge of the resistance element
[0084] 8 Code
[0085] 9 Code
[0086] 10 triangles as code symbols of Code 8
[0087] 11 Rectangles as code symbols of Code 9
[0088] 12 gaps as code symbols in the Code 8
[0089] 13 gaps as code symbols in the Code 9
[0090] 14 bars
[0091] I Current to be measured
[0092] R Resistance value of the SMD current measuring resistor
[0093] RNOMINAL Nominal resistance value of the SMD current measuring resistor
[0094] ±AR F ERT manufacturing tolerance of the resistance value of the SMD current measuring resistor
[0095] RIST Actual value of the resistance of the SMD current measuring resistor
[0096] RMAX Maximum resistance value of the SMD current measuring resistor
[0097] RMIN Minimum resistance value of the SMD current measuring resistor
[0098] RMESS Measured resistance value of the SMD current measuring resistor
[0099] +ARMESS Measurement tolerance of the resistance value of the SMD current measuring resistor
Claims
CLAIMS 1. Method for providing an SMD component, in particular an SMD current measuring resistor, comprising the following steps: a) manufacturing the SMD component with a predetermined nominal value (RNENN) of a component characteristic of the SMD component and a certain manufacturing tolerance (±AR F ERT) of the component characteristic (R), b) measurement of a measured value (R ESS) of the component characteristic of the SMD component with a certain measurement tolerance (±AR M ESS), whereby the measurement tolerance (±AR M ESS) is more accurate than the manufacturing tolerance (±AR F ERT), and c) applying a code (8, 9) to the SMD component, wherein the code (8, 9) contains information about the measured value (RMESS) of the component parameter (R) of the SMD component and / or the measurement tolerance (±AR M ESS).
2. Method according to claim 1, characterized by the following steps for equipping a circuit with the SMD component: a) detecting the position and / or orientation of the SMD component by means of an optical image processing system, b) correcting the position and / or orientation of the SMD component in accordance with the position and / or orientation of the SMD component determined by the image processing system, and c) equipping the circuit with the SMD component after correcting the position and / or orientation of the SMD component.
3. Method according to claim 2, characterized by the following step when equipping the circuit with the SMD component: a) reading the code (8, 9) on the SMD component by means of the image processing system, which also serves to detect the position and / or the orientation of the SMD component when equipping the circuit, or b) reading the code (8, 9) on the SMD component by means of a separate image processing system that is not used to detect the position and / or orientation of the SMD component when assembling the circuit.
4. Method according to claim 3, characterized by the following step: a) determining the measured value (RMESS) of the component characteristic (R) and / or the measurement tolerance (±AR M ESS) from the read code (8, 9), and / or b) storing the measured value (RMESS) of the component parameter (8, 9) and / or the measurement tolerance (±AR M ESS) in the circuit for consideration during circuit operation.
5. SMD component, in particular SMD current measuring resistor, with a) a first code (8) applied to the SMD component, wherein the first code (8) contains information about a first measured value (R ESS) of a first component characteristic (R) of the SMD component and / or a first measurement tolerance (±AR MESS) with which the first measured value (RMESS) was measured, characterized in that b) the first code (8) consists of several geometric symbols (10, 12).
6. SMD component according to claim 5, characterized by a second code (9) applied to the SMD component, wherein the second code (9) consists of several geometric symbols (11, 13) and contains information about a second measured value of a second component characteristic of the SMD component and / or a second measurement tolerance with which the second measured value was measured.
7. SMD component according to claim 6, characterized in that a) the geometric symbols (10, 12) of the first code (8) are arranged on the SMD component in a first row, and / or b) the geometric symbols (11, 13) of the second code (9) are arranged on the SMD component in a second row, and / or c) the first row of the first code (8) and the second row of the second code (9) are arranged parallel to one another on the SMD component, and / or d) the first row of the first code (8) is aligned transversely and / or longitudinally to the main current flow direction in the SMD component, and / or e) the second row of the second code (9) is aligned transversely and / or longitudinally to the main current flow direction in the SMD component, and / or f) a bar (14) is arranged on the surface of the SMD component to indicate the length of the first code (8) and / or the second code (9), and / or g) that the bar (14) is aligned parallel to the first line of the first code (8) and / or parallel to the second line of the second code (9) and / or transversely and / or longitudinally to the main current flow direction in the SMD component.
8. SMD component according to one of claims 5 to 7, characterized in that a) the geometric symbols (10, 11, 12, 13) for coding the first or second component characteristic have different colors, and / or b) the geometric symbols (10, 11, 12, 13) for coding the first or second component characteristic have different brightnesses, and / or c) the geometric symbols (10, 11, 12, 13) for coding the first or second component characteristic have different shapes.
9. SMD component according to one of claims 5 to 8, characterized in that the geometric symbols comprise at least one of the following symbols: a) rectangle (11), b) circles, c) triangle (10), d) gap (12, 13) or e) hexagon.
10. SMD component according to one of claims 5 to 9, characterized in that a) the geometric symbols (10, 12) in the first code (8) are uniform, and / or b) the geometric symbols (11, 13) in the second code (9) are uniform, and / or c) the geometric symbols (10, 12) in the first code (8) are different geometric symbols than in the second code (9), or d) different symbols in a code line are assigned to a code, and / or e) the symbols (10, 11, 12, 13) have the same color, and / or f) the symbols (10, 11, 12, 13) have different colors, and / or g) the color of the symbols (10, 11, 12, 13) has the same brightness, and / or h) the color of the symbols (10, 11, 12, 13) has a different brightness.
11. SMD component according to one of claims 5 to 10, characterized in that the information contained in the first code (8) and / or the information contained in the second code (9) represents at least one of the following component characteristics of the SMD component: a) Resistance value (RMESS), b) Temperature coefficient of resistance, c) Size of the SMD component, d) Mass of the SMD component, e) Date of manufacture of the SMD component, f) Batch number of the SMD component, g) Customer-specific information of the SMD component, h) Measurement tolerance (±AR M ESS) of the component parameters.
12. SMD component according to one of claims 5 to 11, characterized by a design as a current measuring resistor with a) a first connection part (3) made of a conductor material for introducing an electrical current (I) to be measured into the current measuring resistor, b) a second connection part (4) made of a conductor material for conducting the electrical current (I) to be measured out of the current measuring resistor, and c) a resistance element (5) made of a resistance material, wherein the resistance element (5) is arranged in the current flow direction between the first connection part (3) and the second connection part (4), so that the electrical current (I) to be measured flows through the resistance element (5).
13. SMD component according to claim 12, characterized in that a) the first code (8) is applied to the resistance element (5) of the current measuring resistor, and / or b) the second code (9) is applied to the resistance element (5) of the current measuring resistor, or c) the first code (8) is applied to the protective lacquer of the current measuring resistor, and / or d) the second code (9) is applied to the protective lacquer of the current measuring resistor, or e) the first code (8) is applied to a connection part (3, 4) of the current measuring resistor, and / or f) the second code (9) is applied to a connection part (3, 4) of the current measuring resistor.
14. SMD component according to one of claims 12 to 13, characterized in that a) that the first connection part (3), the second connection part (4) and / or the resistance element (5) is plate-shaped, and / or b) that the current measuring resistor has a resistance value of at most 1 Ω, 500 Ω.Q, 250 mQ, 100 mQ, 50 mQ, 25 mQ, 10 m, 5 m, 1 m, 500 pQ, 250 pQ, 100 pQ, 50 pQ or 25 pQ, and / or c) that the current measuring resistor has a length (L) of at most 5 cm, 2 cm, 1 cm, 5 mm or 3 mm in the direction of current flow, and / or d) that the current measuring resistor has a width (B) of at most 5 cm, 2 cm, 1 cm, 5 mm or 3 mm across the direction of current flow, and / or e) that the current measuring resistor has a thickness of at most 5 mm, 3 mm, 2 mm or 1 mm, and / or f) that the first code (8) and / or the second code (9) is optically readable, and / or g) that the conductor material of the connection parts (3, 4) has a lower specific electrical resistance than the resistance material of the resistance element (5), and / or h) that the conductor material of the connection parts (3, 4) is copper, a copper alloy, aluminum or an aluminum alloy, and / or i) that the conductor material of the connection parts (3, 4) has a specific electrical resistance which is less than 5010'.8 Q m, 2010' 8 Q m, 1010' 8 Q m or 510' 8 Q m, and / or j) that the current measuring resistor has a continuous current strength of at least 1 A, 2 A, 5 A, 10 A, 25 A, 50 A, 100 A or 400 A, and / or k) that the resistance material of the resistance element is one of the following alloys: kl) copper-manganese alloy, in particular copper-manganese-nickel alloy, k2) iron-nickel-chromium alloy, k3) nickel-chromium alloy.