Printed circuit board comprising at least two potential sections electrically isolated by a separating section

Abstract

A printed circuit board (1) comprising at least two potential sections (3, 4) separated in an electrically insulating manner by a separating section (2), wherein a first potting compound (5) is arranged on the printed circuit board (1), which at least partially covers the separating section (2), in particular completely, wherein at least one second potting compound (6) is arranged on the printed circuit board (1), which at least partially covers the at least one separating section (2) and / or at least one potential section (3, 4), wherein the first and the second potting compound (5, 6) have different elastic properties, wherein the separating section (2) is designed as a separating trench and the first potting compound (5) completely fills the separating section (2), wherein the second potting compound (6) covers the first potting compound (5) at least partially, characterized in thatthat the material of the first potting compound (5) has a lower hardness and / or a higher elongation at break than the material of the second potting compound (6) and the second potting compound (6) partially touches the first and second potential sections (3, 4).

Description

[0001] The invention relates to a printed circuit board comprising two potential sections separated in an electrically insulating manner by a separating section, wherein the separating section is designed as a separating trench and the first potting compound completely fills the separating section, wherein the second potting compound covers the first potting compound at least in sections.

[0002] Corresponding printed circuit boards are known in principle from the prior art. Printed circuit boards are known that have at least two potential sections separated by an electrically insulating separating section, wherein a first potting compound is arranged on the printed circuit board, which at least partially covers the separating section, in particular completely. Either a hard potting compound or a soft potting compound is used as the potting compound. These potting compounds serve to protect the potential sections and / or the separating sections in order to maintain clearance and creepage distances and / or to protect against environmental influences such as moisture and / or mechanical stress.If a high level of energy is introduced into the circuit board, particularly into a semiconductor chip arranged on the circuit board (in the event of a fault), defects can occur in hard-cast circuit boards. This is because, above a certain temperature, electrically conductive gases can be generated when a high level of energy is introduced, which can cause the hard-cast or solid potting compound to burst free. This destruction of the potting compound, at least in sections, can expose internal structures of the circuit board, e.g., its potential sections, and the clearance and creepage distances are therefore no longer maintained. Finally, the resulting electrically conductive gases and the continued electrical voltage can lead to the formation of an electrical arc between adjacent potential sections.

[0003] JP S57 130 499 A discloses a printed circuit board comprising two potential sections electrically isolatingly separated by a separating section, wherein quartz glass powder and synthetic resin mixed on the printed circuit board are used as an insulator which completely covers the separating section, and wherein solder resist is further arranged on the printed circuit board which covers the separating section and the potential sections.

[0004] The invention is based on the object of specifying a printed circuit board which, in particular with regard to a simple, quick and cost-effective measure, enables greater safety, in particular in the event of a fault, during use of the printed circuit board.

[0005] The object is achieved by a printed circuit board according to claim 1. The dependent claims relate to possible embodiments of the printed circuit board. The object is also achieved by a method according to claim 12. The dependent claims relate to advantageous embodiments of the printed circuit board, as well as a circuit breaker, an electric axle drive, and a motor vehicle with a printed circuit board according to claim 1.

[0006] The invention relates to a printed circuit board comprising at least two potential sections separated in an electrically insulating manner by a separating section, wherein a first potting compound is arranged on the printed circuit board and covers at least the separating section at least partially, in particular completely. The potential sections can each be arranged as conductive, in particular planar, conductor structures on a base support of the printed circuit board. The at least one potential section can comprise copper as a component or be formed from copper. An electronic and / or electrical component, e.g. a computer chip and / or a microcontroller, can be arranged on or at a potential section and / or can be connected for power and / or data transmission.According to the invention, at least one second potting compound is arranged on the circuit board, which at least partially covers the at least one separating section and / or at least one potential section, wherein the first potting compound and the second potting compound have different elastic properties. For example, the material forming the first potting compound and the material forming the second potting compound can have different elastic values ​​or elasticities. For example, the first potting compound can be a soft potting compound and the second potting compound can be a hard potting compound. Essentially, by providing a first section of the circuit board with a first, soft potting compound and a further section with a second potting compound that is harder than the first potting compound, a more powerful circuit board can be achieved because this combines the advantages of hard and soft potting compounds.In the present case, the printed circuit board is formed by a base carrier and potential sections or electrically conductive regions arranged thereon, wherein the printed circuit board further comprises at least two potting compounds with different elastic properties.

[0007] The first potting compound can be arranged directly or indirectly on the printed circuit board. If the first potting compound is arranged directly on the printed circuit board, the first potting compound can be in direct contact with the base support of the printed circuit board, at least in sections, e.g., in the region of a separating section formed as a separating trench. Alternatively or additionally, the first potting compound can be in direct contact, at least in sections, with conductor tracks of the printed circuit board and / or electrical or electronic components on the printed circuit board and / or with electrical connectors connecting potential sections on the printed circuit board, e.g., bonds or bond wires.

[0008] During normal operation of the circuit board, the first and second potential sections can have different electrical voltage potentials, in particular high-voltage potentials. The first and second potential sections can, for example, have the same or different polarities, at least temporarily or permanently, during normal operation of the circuit board. The at least one potential section can, for example, be designed as a so-called leadframe. Thus, the potential section can be designed as a flat conductive body with a plurality of openings and can be arranged in or on a base support, in particular on a base support.

[0009] It is possible for the first potting compound to directly cover the separating section at least in sections, preferably predominantly, particularly preferably completely. Covering the separating section by the first potting compound can mean encapsulation or surrounding of the separating section at least in sections such that the separating section is at least predominantly, particularly preferably completely, separated from the environment by the first potting compound. Direct covering here means contacting covering or covering, i.e. that there is no further element between the first potting compound and the separating section - with the exception of any adhesion promoter - so that the first potting compound directly contacts the separating section. The separating section can be designed, for example, as a separating trench, wherein this trench can be filled by the potting compound at least in sections, preferably predominantly, particularly preferably completely.

[0010] The second potting compound covers the first potting compound, at least in sections, preferably predominantly, particularly preferably completely. The second potting compound has a higher hardness and can, for example, offer greater protection against deformation under mechanical stress. The second potting compound can also have an interface to a component to be fastened to the circuit board, in particular to be fastened to the circuit board in a force-fitting and / or form-fitting manner. For example, the potting compound can have an engagement projection for being received in a component-side receiving recess and / or a receiving recess for receiving a component-side engagement projection. In general, the second potting compound can have a higher rigidity than the first potting compound in its intended state or in the final assembly state of the circuit board.Because the first potting compound is surrounded or covered by the second potting compound at least in sections, preferably predominantly, particularly preferably completely, despite the presence of the first potting compound on a section of the circuit board, this section can have the external properties of the second potting compound, e.g. higher stiffness values, due to the additional, more outward arrangement of the second potting compound.

[0011] The material of the first potting compound has a lower hardness and / or a higher elongation at break than the material of the second potting compound. Due to the higher elongation at break of the first potting compound, even in the event of a section-by-section break of the second potting compound, a "sealing" of defined sections of the circuit board from the environment can be achieved by the first potting compound, which has a later tendency to break due to the higher elongation at break. This reduces or eliminates the risk of an arc forming, caused by a break in the second potting compound or a hard potting compound. This makes it possible to detect different voltage potentials within the circuit board ora power module comprising the circuit board to be arranged close to one another and to be separated from one another via the separating sections, whereby the soft potting compound, even in the event of the hard potting bursting, provides sufficient sealing of the burst areas and thus sufficient electrical insulation or sufficient protection against the formation of arcs at the burst areas.

[0012] By forming regions on the circuit board at least in sections where the first and second potting compounds can contact each other, these regions have a tendency to fracture because the adhesion of the first and second potting compounds to each other can be reduced. Consequently, if the first potting compound is arranged in the region of a critical electrical voltage point or a critical electrical high-voltage point, this point may be more likely to fracture due to the lower adhesion, but it can remain sufficiently sealed by the elastic first potting compound, preventing the formation of an arc.

[0013] For example, a material with a Shore A hardness according to DIN ISO 7619-1 in the range from 5 to 150, preferably in the range from 20 to 90, more preferably from 20 to 50, more preferably from 20 to 30, can be used as the first casting compound. Alternatively or additionally, the Shore A hardness can be a maximum of 90, preferably a maximum of 50, preferably a maximum of 30. The elongation at break according to DIN 53504 S2 of the first casting compound can be, for example, at least 100%, preferably at least 200%, more preferably at least 300%, most preferably at least 400%, more preferably at least 475%. The tensile strength according to DIN 53504 S2 of the first casting compound can be, for example, in the range from 0.5 to 4.0, preferably from 1.0 to 2.5 N / mm 2 , lay.

[0014] A soft potting compound can be used as the first potting compound, e.g. the first potting compound consists at least partially, preferably predominantly, particularly preferably completely, of silicone and / or a 2-component gel. Alternatively or additionally, the first potting compound can consist of a material that is applied to the circuit board in pasty and / or liquid form to form the potting compound on the circuit board and that hardens under the influence of air and / or UV light and / or thermal energy. This hardening thereby forms an increase in the hardness of the potting compound relative to the state in which it was applied to the circuit board. Accordingly, a hardening that significantly increases the degree of hardness towards harder forms a hardening in the present sense. For example, the first potting compound canas a so-called cold-curing silicone (rubber), also known as RTV (room temperature curing), or as a hot-curing silicone (rubber), also known as HTV (high temperature curing). It can be provided that the material of the first potting compound and the material of the second potting compound have different thermal expansion coefficients. The difference in the expansion coefficients of the two potting compounds can differ, for example, by a factor of 1.25, preferably 1.50, and particularly preferably 2.0.

[0015] It can be provided that the first potting compound has a permanent elasticity, whereas the second potting compound has no or no significant elasticity (anymore) after its application to the circuit board and after its curing.

[0016] Preferably, the second potting compound may consist of a hard potting material or comprise such a material and / or consist of an injection molding material, in particular a plastic injection molding material, or comprise such a material.

[0017] To form the first and / or second potting compound, it can be provided that a shaping mold is placed on the circuit board and forms a cavity, wherein the cavity is then filled at least partially with the first and / or second potting compound, wherein the tool-side, with walls defining the cavity, has a shaping effect on the potting compound introduced into the cavity. Preferably, a first tool is used to form the target shape of the first potting compound by means of a first cavity and a second tool is used to form the target shape of the second potting compound by means of a second cavity. The respective tools can each have the geometries corresponding to the target shape of the first and second potting compound.It is also possible to use a single tool, wherein at least one wall section of the tool can be changed in its position and / or orientation in order to form a first cavity and a second cavity different from the first cavity.

[0018] By placing an adhesion promoter (a) between the first potting compound and the second potting compound and / or (b) between the circuit board and the first potting compound and / or (c) between the circuit board and the second potting compound, the connection or adhesion of the respective connecting partners can be positively influenced. The adhesion promoter can, for example, be an adhesive and / or be made of a material from an organic group.

[0019] It is possible for a bond connection to be arranged between at least one first potential section and at least one second potential section, wherein the at least one bond connection is completely, in particular directly, surrounded by the first potting compound. In other words, an electrical connector or a bond connection connecting the first potential section to the second potential section is surrounded by the first potting compound at least in sections, preferably predominantly, preferably completely. Thus, the first potting compound can be provided to separate or encapsulate the electrical connector or the bond connection from the environment and / or from a second potting compound. Optionally, the first potting compound can surround or embed the bond connection at least in sections, preferably predominantly, particularly preferably completely. The first potting compound can preferably surround the bond connection directly, i.e.directly touching them. By separating the bond connection from the environment and / or from a second potting compound, the risk of fracture initiation by the bond contact can be reduced and / or prevented. If the bond contact of the bond connection with a potential section and / or with an electrical or electronic component arranged on a potential section were provided with a hard potting compound, this could promote the initiation of fracture of the hard potting compound or increase the risk of fracture of the potting compound of the printed circuit board. It can prove advantageous if the majority, preferably all, of the bond connections and / or the bond contacts (the end sections of the bond connections) are completely surrounded or embedded by the first potting compound.For this purpose, the first potting compound can be formed as a potting structure of the first potting compound comprising several separate sections, or the first potting compound can be present as a continuous potting structure of the first potting compound. A bond connection is understood to be an electrical conductor that represents an electrical connection bridging or spanning the separating section. The bond connection or a bond connector can be formed, for example, as a rib bond and / or as a copper strip.

[0020] It is possible for a separating section between the first and second potential sections to be formed as an intermediate space separating the potential sections, and for the intermediate space to be filled with the first potting compound, at least in sections, preferably predominantly, particularly preferably completely. Thus, the first and the at least one second potential section can preferably be arranged within a common plane and, due to interruptions, form electrically separated potential sections. The space between these interruptions, if filled with air, would form a potential conductor bridge or arc bridge if corresponding electrical potentials, in particular high-voltage potentials, were present. Alternatively or additionally, at least one separating section can be formed as a raised section on the circuit board or as a section provided with an insulating element.In the case of a raised insulating element, this could be covered by the first casting compound at least in sections, preferably predominantly, particularly preferably completely.

[0021] In a preferred optional development, it can be provided that the first potting compound is arranged above a surface of the first and / or second potential section. Thus, the first potting compound can extend, at least in sections, into an area that is at a greater distance from the base support of the circuit board than the maximum elevation of the first and / or second potential section. Thus, the potential section can not only fill a direct line between two potential sections and thus electrically insulate them, but also form a further barrier to electrical flow between the first and second potential sections.For example, the height of the potting compound above the surface of the first and / or second potential section can be at least a factor of 0.30, preferably 0.5, particularly preferably 1.0, most preferably 1.5, and further preferably 2.0, of the height of the first and / or second potential section from a support structure or base support supporting the potential sections to the surface of the first and / or second potential section. In other words, the first potting compound projects beyond the separation section formed as a separation trench by at least the aforementioned factors with respect to the height or depth of the separation trench.

[0022] The potential section can be formed as a substrate, e.g., at least one copper substrate. The potential section can be formed, e.g., as a flat electrically conductive element. This flat element can be arranged on a base carrier, e.g., on a ceramic plate or a plate having a ceramic as a component. For example, an electronic or electrical component, e.g., a computer chip, can be arranged on at least one potential section.

[0023] It is also possible for the first and / or second potential sections to form a component of a lead frame, also referred to as a "connection frame." This lead frame forms a metallic conductor carrier, e.g., in the form of a frame or a comb for the mechanical production of semiconductor chips or other electronic components. The lead frame can thus form a component of the printed circuit board described herein. The lead frame can be mounted on an insulating carrier, i.e., on the base carrier.

[0024] It is possible for the first potting compound, starting from the intermediate space or starting from a region located in the intermediate space, to cover at least one adjacent potential section at least partially on its upper side and form a covering section of the first potting compound. In other words, the covering section overlaps at least partially the edge region of the first and / or second potential section adjacent to the intermediate space. Consequently, the covering section of the first potting compound can have a lateral coverage of at least one potential section along a longitudinal axis of the circuit board that corresponds to at least a factor of 0.25, preferably 0.50, particularly preferably 1.00, most preferably 1.50, further preferably 2.50, of the length of the separating section along the longitudinal axis of the circuit board.Viewed in cross-section, the first potting compound can have a mushroom-like shape and / or a T-like shape, wherein a mushroom stem of the mushroom-like shape or the middle T-web forms the intermediate space filled by the first potting compound. The mushroom head or the two short T-webs form the covering section of the first potting compound that lies above the potential sections and at least partially covers at least one potential section. Optionally, the cross-sectional shape of the potting compound can be in a sectional plane that is oriented perpendicular to a straight line of a linear separating section. The cross-sectional shape of the first potting compound can, for example, have the shape of a flat-spherical or hemispherical screw head.

[0025] During normal operation, the circuit board is operated with high voltages, e.g., the circuit board is used in a power module of a motor vehicle.

[0026] In addition to the printed circuit board, the invention also relates to a circuit breaker and / or a power converter, in particular an inverter, with a printed circuit board described herein. The circuit breaker can thus comprise the printed circuit board described herein and having at least two potting compounds of different elasticities. The circuit breaker is preferably used for applications in the high-voltage range. The invention also relates to an electric axle drive for a motor vehicle with at least one electric machine, a transmission device and a circuit breaker and / or power converter described herein. Furthermore, the invention relates to a motor vehicle comprising an electric axle drive described herein and / or a circuit breaker and / or power converter described herein and / or a printed circuit board described herein.Finally, the invention relates to a method for producing a printed circuit board described herein, wherein the method comprises the following method steps: arranging the first potting compound on the printed circuit board and arranging the second potting compound on the printed circuit board, wherein the first and second potting compounds are applied to the printed circuit board simultaneously, overlapping in time, or offset in time. The first potting compound can, for example, cover at least one separating section. Preferably, the predominant separating section, particularly preferably all separating sections, of the printed circuit board are completely covered, in particular directly, by the first potting compound. In other words, it can be provided that the at least one separating section of the printed circuit board is first completely covered by the first potting compound before the second potting compound is applied to the printed circuit board.Optionally, it is possible to first apply a portion of the second potting compound to the areas of the circuit board spaced apart from the separating sections, then arrange the first potting compound at the at least one separating section, and then apply another portion of the second potting compound to the first potting compound. For example, when applying the second portion of the second potting compound, it is brought into contact with the first portion of the second potting compound or forms a connection with it.

[0027] It is possible that the second encapsulant is applied to the first encapsulant only after the first encapsulant has cured. For example, the first encapsulant is cured thermally and / or UV-light-assisted.

[0028] All advantages, details, designs and / or features of the printed circuit board according to the invention are applicable to the circuit breaker and / or power converter, in particular inverter, and / or axle drive and / or motor vehicle and / or method according to the invention and vice versa.

[0029] The invention is explained in more detail using exemplary embodiments in the drawings. In the drawings: Fig. 1 a perspective schematic representation of components of a printed circuit board according to an embodiment; Fig. 2 a perspective schematic diagram of a separating section of a printed circuit board designed as a separating trench according to an embodiment; Fig. 3 a schematic plan view of a separating section of a printed circuit board provided with a first potting compound according to an embodiment; Fig. 4 a schematic side view of a separating section separating two potential sections of a printed circuit board, which is covered with a first and a second potting compound according to an embodiment.

[0030] In Fig. 1 shows some of the components of a printed circuit board 1, which comprises potential sections 3, 4 formed from an electrically conductive material. The printed circuit board 1 comprises at least two potential sections 3, 4 which are electrically insulated and separated by a separating section 2. A first potting compound 5 is arranged on the printed circuit board 1, which at least partially covers the separating section 2, in particular completely. The potting compound 5 prevents mechanical influences, e.g., contact of a third object with the separating section 2. According to the invention, at least one second potting compound 6 is arranged on the printed circuit board 1, which at least partially covers the at least one separating section 2 and / or at least one potential section 3, 4, wherein the first and second potting compounds 5, 6 have different elastic properties. Fig. 4 shows, by way of example, that the separating section 2, designed as a trench or as a separating trench, is filled, in particular completely, with the first potting compound 5, and a second potting compound 6 is arranged above the first potting compound 5. For example, the second potting compound 6 can surround the separating section 2 and / or at least one potential section and / or the first potting compound 5, at least in cross-section, without gaps, preferably completely without gaps.

[0031] The first casting compound 5 can, for example, directly cover the separating section 2 at least in sections, preferably predominantly, particularly preferably completely, cf. Fig. 4. For this purpose, the first potting compound can completely fill the separating section 2 formed as a recess or trench. In other words, the first potting compound 5 can be applied in such a quantity that the walls of the adjacent potential sections 3, 4 defining a separating trench are in contact, in particular completely, with the first potting compound 5.

[0032] The material of the first potting compound 5 can, for example, have a lower hardness and / or a higher elongation at break than the material of the second potting compound 6. This reinforces the effect that, in the event of a fault or damage to a potting compound 5, 6, it is less prone to breakage or the formation of gaps that would expose at least one section of an isolating section 2 and / or a potential section 3, 4, which is intended to be shielded by at least one potting compound 5, 6, to the environment. This can increase the operational safety of a printed circuit board, particularly if it carries currents or electrical voltages in the high-voltage range in the potential sections 3, 4.

[0033] Preferably, the first potting compound 5 is formed from or comprises a silicone and / or a two-component gel. Optionally, the first potting compound 5 consists of or comprises a material that is applied to the circuit board 1 in pasty and / or liquid form and cures under the influence of air and / or UV light and / or thermal energy. After curing, the first potting compound 5 can exhibit a residual elasticity that corresponds, for example, to the values ​​of a silicone in the final assembly state.

[0034] The second potting compound 6 can, for example, consist of a hard potting material or comprise such a material. Optionally, the second potting compound 6 can consist of an injection-molded material, in particular a plastic injection-molded material, or comprise such a material. The second potting material can, for example, be formed from thermoplastic plastic. For example, the second potting compound can comprise polyolefins, e.g., polypropylene, or Plexiglas (PMMA) or polycarbonate (PC) or polystyrene (PS), in particular its copolymers (acrylonitrile butadiene styrene), or polyamide (PA) or polyoxymethylene (POM) as material. In general, the second potting compound can comprise or form an interface function for connecting a third object, e.g., a connector body, to the printed circuit board.

[0035] For example, a bond connection 7 can be arranged between at least one first potential section 3, 4 and at least one second potential section 3, 4, wherein the at least one bond connection 7 is completely, in particular directly, surrounded by the first potting compound 5 (not shown). Fig. In the embodiment shown in Figure 4, the bond connection 7 is not surrounded or touched by the first potting compound 5, but exclusively by the second potting compound 6.

[0036] A separating section 2 can be formed, for example, between the first and second potential sections 3, 4 as an intermediate space 8 that electrically separates the potential sections 3, 4 at least in sections. Fig. 2, the separating section 2 is designed as a separating trench. The separating trench can, for example, be U-shaped, with the parallel free U-legs being formed by the sides of the at least two potential sections 3, 4 directly adjacent to the separating trench, and the central U-web being formed by a base support 16 of the circuit board. The interior of the U-shaped separating trench forms the intermediate space 8, which is filled by the first potting compound, at least in sections, preferably predominantly, and particularly preferably completely.

[0037] The printed circuit board 1 comprises a base support 16, which can be designed, for example, as a plate or plate-shaped. The base support 16 can, for example, consist of or comprise a ceramic material. The base support 16 can, for example, have a supporting function for (a) potential sections 3, 4, e.g., in the form of a copper structure, and / or (b) electrical and / or electronic components 17, such as computer chips, applied thereto. The electrical and / or electronic component 17 can be connected to the base support 16 or carried by it, at least in sections, directly and / or at least in sections indirectly via a potential section 3, 4. Furthermore, the printed circuit board optionally comprises electrical connections, e.g., bond connections 7, which connect individual potential sections 3, 4 directly or indirectly to one another. Thus, in Fig. 4, the second potential region 4 is electrically conductively connected to the first potential section 3 via the electrical and / or electronic component 17 arranged thereon and the bond connection 7. It is possible for the bond connection 7 to run at least partially, preferably predominantly, particularly preferably entirely, along a separation region between the first and second potting compounds. In other words, the bond connection 7 can be in contact with the first and second potting compounds 3, 4 at least partially, preferably predominantly, particularly preferably entirely, along its longitudinal extent (not shown).

[0038] It is possible for the first potting compound 5 to be arranged above a surface 9 of the first and / or second potential section 3, 4. For example, the height 11 of the first potting compound 5 above the surface 9 of the first and / or second potential section 3, 4 can be at least a factor of 0.30, preferably 0.5, particularly preferably 1.0, most preferably 1.5, further preferably 2.0, of the height 10 of the first and / or second potential section 3, 4 from a base support 16 supporting the potential sections 3, 4 to the surface 9 of the first and / or second potential section 3, 4. In other words, the height 10 is defined by the distance of the surface of the base support 16 facing the potential section 3, 4 to the surface 9 of the first and / or second potential section 3, 4.

[0039] The first potting compound 5 can, for example, starting from the intermediate space 8, cover at least one adjacent potential section 3, 4 at least partially on its upper side 9 and form a covering section 12 of the first potting compound 3. Preferably, the covering section 12 of the first potting compound 3 has a lateral covering 13 or a length of a lateral covering 13 (cf. Fig. 3, Fig. 4) at least one potential section 3, 4 along a longitudinal axis 14 of the circuit board 1, which corresponds to at least a factor of 0.25, preferably 0.50, particularly preferably 1.00, most preferably 1.50, further preferably 2.50, of the length 15 of the separating section 2 along the longitudinal axis 14 of the circuit board 1. Thus, the coverage 13 of the covering section 12 can overlap or project beyond the upper side of the potential sections 3, 4 adjacent to the separating section 2, at least at the edge. Preferably, the overlap or the coverage 13 is constant along the course of the separating section 2 to at least one adjacent potential section 3, 4, preferably to both adjacent potential sections 3, 4, cf. Fig. 3.

[0040] Furthermore, the invention relates to a circuit breaker (not shown) and / or power converter (not shown), in particular an inverter (not shown), with a circuit board 1 described herein. The invention also relates to an electric axle drive (not shown) for a motor vehicle (not shown) with at least one electric machine (not shown) described herein, a transmission device (not shown) and a circuit breaker and / or power converter described herein.

[0041] The invention also encompasses a method for producing a printed circuit board 1 described herein, comprising the method steps of: arranging the first potting compound 5 on the printed circuit board 1 and arranging the second potting compound 6 on the printed circuit board 1, wherein the first and second potting compounds 6 are applied to the printed circuit board 1 simultaneously, overlapping in time, or, in particular, completely offset in time. Thus, it can be provided that the second potting compound 6 is only applied to the first potting compound 6 after the first potting compound 5 has cured or has its intended elasticity. List of reference symbols 1 circuit board 2 Separation section 3 first potential section 4 second potential section 5 first casting compound 6 second casting compound 7 Bond connection 8 gap 9 Surface of 3, 4 10 height of 3, 4 11 height of 5 above 3, 4 12 Cover section of 3 13 Coverage 14 Longitudinal axis of 1 15 length of 2 16 base supports 17 electrical and / or electronic components

Claims

[1] A printed circuit board (1) comprising at least two potential sections (3, 4) separated in an electrically insulating manner by a separating section (2), wherein a first potting compound (5) is arranged on the printed circuit board (1), which at least partially covers the separating section (2), in particular completely, wherein at least one second potting compound (6) is arranged on the printed circuit board (1), which at least partially covers the at least one separating section (2) and / or at least one potential section (3, 4), wherein the first and the second potting compound (5, 6) have different elastic properties, wherein the separating section (2) is designed as a separating trench and the first potting compound (5) completely fills the separating section (2), wherein the second potting compound (6) covers the first potting compound (5) at least partially, characterized bythat the material of the first potting compound (5) has a lower hardness and / or a higher elongation at break than the material of the second potting compound (6) and the second potting compound (6) partially touches the first and second potential section (3, 4). [2] Printed circuit board (1) according to claim 1, characterized by that the first casting compound (5) directly covers the separating section (2) at least in sections, preferably predominantly, particularly preferably completely. [3] Printed circuit board (1) according to one of the preceding claims, characterized by , that - the first casting compound (5) consists of or comprises a silicone and / or a 2-component gel and / or that - the first potting compound (5) consists of a material which is applied to the printed circuit board (1) in pasty form and / or liquid form and cures under the influence of air and / or UV light and / or thermal energy. [4] Printed circuit board (1) according to one of the preceding claims, characterized by , that - the second potting compound (6) consists of a hard potting material or comprises such a material, and / or - the second casting compound (6) consists of an injection-moulding material, in particular of a plastic injection-moulding material, or comprises such a material. [5] Printed circuit board (1) according to one of the preceding claims, characterized by that a bond connection (7) is arranged between at least one first potential section (3, 4) and at least one second potential section (3, 4), wherein the at least one bond connection (7) is completely, in particular directly, surrounded by the first potting compound (5). [6] Printed circuit board (1) according to one of the preceding claims, characterized byin that the first potting compound (5) is arranged above a surface (9) of the first and / or second potential section (3, 4), the height (11) of the first potting compound (5) above the surface (9) of the first and / or second potential section (3, 4) is preferably at least a factor of 0.30, preferably 0.5, particularly preferably 1.0, most preferably 1.5, further preferably 2.0, of the height (10) of the first and / or second potential section (3, 4) from a base support (16) carrying the potential sections (3, 4) to the surface (9) of the first and / or second potential section (3, 4). [7] Printed circuit board (1) according to one of the preceding claims, characterized byin that the first potting compound (5), starting from the intermediate space (8), covers at least one adjacent potential section (3, 4) at least in sections on its upper side (9) and forms a covering section (12) of the first potting compound (5), preferably the covering section (12) of the first potting compound (5) has a lateral covering (13) of at least one potential section (3, 4) along a longitudinal axis (14) of the printed circuit board (1), which corresponds to at least a factor of 0.25, preferably 0.50, particularly preferably 1.00, most preferably 1.50, further preferably 2.50, of the length (15) of the separating section (2) along the longitudinal axis (14) of the printed circuit board (1). [8] Circuit breaker with a printed circuit board (1), characterized by that the circuit board (1) is designed according to one of the preceding claims. [9] Electric axle drive for a motor vehicle with at least one electric machine, a transmission device and a circuit breaker, characterized by that the circuit breaker is designed according to claim 8. [10] Motor vehicle, comprising an electric axle drive according to claim 9 and / or a circuit breaker according to claim 8 and / or a printed circuit board (1) according to one of claims 1 to 7. [11] Method for producing a printed circuit board (1) according to one of claims 1 to 7, characterized by the procedural steps: - Arranging the first potting compound (5) on the circuit board (1) and - Arranging the second potting compound (6) on the circuit board (1), wherein the first and the second potting compound (6) are applied to the circuit board (1) simultaneously or overlapping in time or offset in time. [12] Method according to claim 11, characterized bythat the second casting compound (6) is only applied to the first casting compound (5) after the first casting compound (5) has cured.

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