CN220915494U - PCB and automobile electronic control module - Google Patents

Abstract

The utility model discloses a PCB and an automobile electronic control module, wherein the PCB comprises: the wiring layers are sequentially stacked; the passive element adopts a metal wiring structure corresponding to the type of the passive element, the passive element is arranged on at least one wiring layer, the metal wiring structure in the PCB is used as the passive element, the standard passive element adopting the PCB layout structure to replace an entity is realized, the reliability of the passive element is improved, the after-market problem caused by the element quality problem is reduced, and meanwhile, the performance of the passive element can be changed by adjusting the metal wiring structure of the passive element, so that the optimal design of a more efficient matching circuit is realized or the EMC problem is solved, the customizable of the element is realized, and the complexity of design work is reduced.

Description

PCB and automobile electronic control module

Technical Field

The application relates to the technical field of PCB design, in particular to a PCB and an automobile electronic control module.

Background

The automobile electric control consists of a plurality of active elements such as large-function integrated ICs and passive elements (also called passive elements) such as resistors, capacitors and inductors. Failure of either element can lead to loss of control or power to the vehicle, leading to safety concerns.

Passive components such as physical resistor, capacitor, inductor and the like are generally welded on the surface of a PCB (Printed Circuit Board ) through a welding pad in the current automobile electric control product. Failure of these passive components generally results in damage due to prolonged operation in high temperature, high humidity environments. In order to solve the problems of high humidity, dust and the like of the environment, a mode of spraying three-proofing paint is generally adopted at present to improve the protection of a passive element, but the mode can bring about another failure under the high-temperature and high-humidity environment, the thermal expansion and contraction of the three-proofing paint can cause the stress between the element and the bonding pad to be aggravated, and the element is invalid or damaged, for example, cold joint, open circuit or short circuit appear on the resistor, copper wire cold joint appears on the inductor, and cracks appear on the capacitor.

In addition, the resistor, the capacitor and the inductor are all standard components at present, in order to match the optimal circuit performance or solve the EMC problem, nonstandard components are needed in some cases, at this time, the components are needed to be subjected to customized design, and the customized change of the production line of a provider is difficult, so that the complexity of the design work is improved.

Therefore, how to provide a PCB board capable of improving the reliability of the element and realizing the customizable element is a technical problem to be solved at present.

Disclosure of utility model

The embodiment of the application provides a PCB and an automobile electronic control module, which are used for improving the reliability of elements in the PCB and realizing the customization of the elements.

In a first aspect, a PCB board is provided, comprising: the wiring layers are sequentially stacked; and the passive element is structurally characterized by adopting a metal wiring structure corresponding to the type of the passive element, and the passive element is arranged on at least one wiring layer.

In some embodiments, there is a connection relationship between passive elements in different wiring layers, connected by vias or buried vias.

In some embodiments, the passive element is a combination comprising any one or more of a resistor, an inductor, and a capacitor.

In some embodiments, the metal wiring structure of the resistor comprises wiring in a circular arc by using metal wires or wiring in a long-distance wire-wound mode of 45 degrees by using metal wires.

In some embodiments, if the resistance value of the resistor is R, the conductivity of the metal line is ρ, the cross-sectional area of the metal line is a, and the length of the metal line is L, the resistance value of the resistor satisfies: r=ρ (L/a), wherein when the cross section of the metal wire is rectangular, the thickness of the metal wire is 1-2oz, and the wire diameter of the metal wire is 8-20mil.

In some embodiments, the metal wiring structure of the inductor comprises a coil formed by adopting a metal wire to spirally surround in a circular arc on a plane, or a coil formed by adopting a metal wire to spirally surround in a 45-degree plane.

In some embodiments, if the inductance value of the inductor is L, where the unit of L is uH, the multilayer coil coefficient is L ₀, the number of turns of the coil is W, the outer diameter of the coil is D, and the unit of D is cm, the inductance value of the inductor satisfies: l=l ₀×W²×D×10^-3, wherein when the cross section of the metal wire is rectangular, the thickness of the metal wire is 1-2oz, and the wire diameter of the metal wire is 8-20mil.

In some embodiments, the passive element further includes a transformer, and/or a common-mode inductor, and/or a common-mode filter, where the transformer, the common-mode inductor, and the common-mode filter each include a primary coil and a secondary coil, the primary coil and the secondary coil adopt the same metal wiring structure as the inductor, and the primary coil and the secondary coil are disposed on the same wiring layer or on different wiring layers according to a preset turns ratio.

In some embodiments, the metal wiring structure of the capacitor includes two metal foils with the same shape as electrode plates, and the two electrode plates are oppositely disposed on different wiring layers, where if the capacitance value of the capacitor is C, the dielectric constant is epsilon, the surface area of the electrode plate is a, and the distance between the two electrode plates is d, the capacitance value of the capacitor satisfies: c=epsilon a/d.

In a second aspect, an automotive electronic control module is provided, which comprises a PCB board according to the first aspect.

Through the application of the technical scheme, the PCB board includes: the wiring layers are sequentially stacked; the passive element is arranged on at least one wiring layer by adopting a metal wiring structure corresponding to the type of the passive element, so that the standard passive element adopting the PCB layout structure to replace an entity is realized by taking the metal wiring structure in the PCB as the passive element, the reliability of the passive element is improved, the after-market problem caused by the quality problem of the element is reduced, and meanwhile, the performance of the passive element can be changed by adjusting the metal wiring structure of the passive element, thereby more efficiently optimally designing a matching circuit or solving the EMC problem, realizing the customization of the element and reducing the complexity of design work.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 shows a schematic structural diagram of a PCB board according to an embodiment of the present utility model;

FIG. 2 illustrates a top view of a metal wiring structure of a resistor in an embodiment of the present utility model;

FIG. 3 illustrates a side view of a metal wiring structure of a resistor in an embodiment of the present utility model;

FIG. 4 shows a side view of a metal wiring structure of a resistor in another embodiment of the utility model;

FIG. 5 illustrates a top view of a metal wiring structure of an inductor in an embodiment of the present utility model;

FIG. 6 illustrates a side view of a metal wiring structure of an inductor in an embodiment of the present utility model;

FIG. 7 illustrates a top view of a metal wiring structure of a capacitor in an embodiment of the utility model;

FIG. 8 illustrates a side view of a metal wiring structure of a capacitor in an embodiment of the utility model;

Fig. 9 is a top view of a transformer/common-mode inductor/common-mode filter formed by arranging a primary coil and a secondary coil on the same wiring layer in an embodiment of the present utility model;

Fig. 10 shows a side view of a transformer/common-mode inductance/common-mode filter with a primary coil and a secondary coil disposed at different wiring layers in an embodiment of the utility model;

FIG. 11 is a schematic diagram of an RC filter circuit according to an embodiment of the present utility model;

Fig. 12 is a schematic diagram showing a wiring structure of the RC filter circuit of fig. 11 in a PCB board;

Fig. 13 shows a numerical graph of the multilayer coil coefficient L ₀.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

An embodiment of the present application provides a PCB board, as shown in fig. 1, including:

A plurality of wiring layers 10, each wiring layer 10 being stacked in order;

The passive element 20, the structure of the passive element 20 adopts a metal wiring structure corresponding to the self type, and the passive element 20 is arranged on at least one wiring layer 10.

In this embodiment, the PCB board includes a plurality of wiring layers 10, each of the wiring layers 10 is stacked in sequence to form each level of the PCB board, and each of the wiring layers 10 is made of a dielectric material. The passive elements 20 are not standard solid elements, but are fabricated with corresponding metal wiring structures according to the type of passive elements 20, and different types of passive elements 20 may be fabricated with different metal wiring structures. The passive element 20 is disposed on at least one wiring layer 10, for example, the passive element 20 is embedded on the surface of the wiring layer 10.

Alternatively, the same type of passive elements may be disposed on the same wiring layer or on different wiring layers. Different types of passive elements can be arranged on different wiring layers or the same wiring layer in different areas on the PCB, and also can be arranged on different wiring layers in the same area on the PCB, so that the passive elements can be flexibly arranged according to actual needs by a person skilled in the art.

Alternatively, the number of wiring layers may be 2-10 layers.

The metal wiring structure in the PCB is used as the passive element, so that the standard passive element adopting the PCB layout structure to replace an entity is realized, the reliability of the passive element is improved, the after-market problem caused by the element quality problem is reduced, and meanwhile, the performance of the passive element can be changed by adjusting the metal wiring structure of the passive element, so that the optimal design of a more efficient matching circuit is realized or the EMC problem is solved, the customizable element is realized, and the complexity of design work is reduced.

In some embodiments of the present application, there is a connection relationship between passive elements in different wiring layers, connected by vias or buried vias.

The vias, also known as through holes, are holes that are all open from the top layer to the bottom layer of the PCB. The buried hole is formed in the inner layer of the PCB, and the upper surface and the lower surface of the buried hole are both arranged in the PCB. In this embodiment, some passive elements in different wiring layers have a connection relationship, and a via hole or a buried hole is provided in the PCB board to connect the corresponding passive elements, so as to achieve reliable electrical connection between the passive elements.

In some embodiments of the application, the passive element is a combination comprising any one or more of a resistor, an inductor, and a capacitor.

In this embodiment, the passive element may be a single resistor, a single inductor, a single capacitor, a plurality of resistors connected in series or in parallel, a plurality of inductors connected in series or in parallel, or a plurality of capacitors connected in series or in parallel, or different combinations of resistors, inductors and capacitors, which can be flexibly arranged according to actual needs by a person skilled in the art to form different passive elements.

In some embodiments of the application, the resistive metal wiring structure includes wiring in a circular arc using metal wires or wiring in a 45 ° long distance wire-wound using metal wires.

In this embodiment, the metal wiring structure of the resistor may adopt two modes, one is to adopt metal wires to wire according to circular arcs, and the design adopts elliptical angle wiring, so that the transverse space can be saved, and the resistor has better EMC characteristics. The other is that the metal wires are adopted to conduct wire winding type wiring according to a long distance of 45 degrees, the design is criss-cross, the wiring is simple and efficient, and the EMC effect is good.

Fig. 2 shows a top view of a metal wiring structure of a resistor in an embodiment of the present utility model, and fig. 3 is a corresponding side view. In fig. 2 and 3, three resistors R1, R2 and R3 are connected in series. The upper metal wiring structure in fig. 2 and 3 is to use metal wires to route in an arc, one end of the metal wires is routed from the 1 st layer (i.e. the top wiring layer of the PCB board), the other end of the metal wires is routed from the n-th layer (i.e. the n-th wiring layer of the PCB board), and n is an integer greater than 1. The lower metal wiring structure in fig. 2 and 3 is a wire-wound type wiring of 45 ° long distance with a metal wire, one end being routed from the 1 st layer and the other end being routed from the n-th layer. The resistors of different wiring layers are connected through via holes or buried holes.

Fig. 4 is a side view of a metal wiring structure of a resistor according to another embodiment of the present utility model, in which R2 and R3 are connected in parallel and then connected in series with R1 in fig. 4, and the metal wiring structure of the upper part in fig. 4 is a structure in which metal wires are wired in an arc, one end of each metal wire is wired from the 1 st layer, and the other end of each metal wire is wired from the n-th layer. The lower metal wiring structure in fig. 4 is a long-distance wire-wound type wiring of 45 ° with metal wires, one end being routed from the 1 st layer and the other end being routed from the n-th layer. The resistors of different wiring layers are connected through via holes or buried holes, so that series connection or parallel connection of the resistors of different wiring layers is realized.

In fig. 3 and 4, the resistors in the different wiring layers with connection relation have the same metal wiring structure, alternatively, the resistors in the different wiring layers with connection relation may be set to have different metal wiring structures, for example, R2 in fig. 3 may be set to be wired with a metal wire at a long distance of 45 °.

Alternatively, a plurality of resistors having connection relationship may be disposed on the same wiring layer, for example, R2 and R3 in fig. 3 may be disposed on the same wiring layer, where different resistors in the same wiring layer may use the same metal wiring structure, or may use different metal wiring structures.

Alternatively, the material of the metal wire in the resistor may be copper, or silver alloy, etc., and the cross section of the metal wire may be rectangular, or circular, etc.

In some embodiments of the present application, if the resistance of the resistor is R, the conductivity of the metal wire is ρ, the cross-sectional area of the metal wire is a, and the length of the metal wire is L, the resistance of the resistor satisfies: r=ρ (L/a), wherein when the cross section of the metal wire is rectangular, the thickness of the metal wire is 1-2oz, and the wire diameter of the metal wire is 8-20mil.

In this embodiment, the calculation formula of the resistance is: r=ρ (L/a), where R is the resistance of the resistor, and after determining the conductivity ρ and the cross-sectional area a of the metal line, the resistor is formed by using a metal line of a corresponding length according to the resistance of the resistor. If the cross section of the metal wire is rectangular, the cross section a is calculated according to the product of the width (i.e. the wire diameter) and the thickness of the metal wire, and if the cross section of the metal wire is circular, the cross section a is determined according to a circular area calculation formula, wherein when the cross section of the metal wire is rectangular, the thickness of the metal wire is 1-2oz, and the wire diameter of the metal wire is 8-20mil.

In some embodiments of the application, the metal wiring structure of the inductor comprises a coil formed by adopting a metal wire to spirally surround in a circular arc on a plane, or a coil formed by adopting a metal wire to spirally surround in a 45-degree plane.

In this embodiment, the metal wiring structure of the inductor can adopt two modes, one is that a coil is formed by adopting a metal wire to spirally surround the plane according to an arc, and the design adopts elliptical angle wiring, so that the transverse space can be saved, and the inductor has better EMC characteristics. The other is to form a coil by adopting a metal wire to spirally surround the coil at 45 degrees on the plane, the design is criss-cross design, the wiring is simple and efficient, and the EMC effect is good.

Fig. 5 shows a top view of a metal wiring structure of a resistor in an embodiment of the present utility model, and fig. 6 is a corresponding side view. The metal wiring structure in fig. 5 and 6 is a coil formed by spirally winding a metal wire in a circular arc on a plane, one end of which is routed from the 1 st layer, and the other end of which is routed from the n-th layer. The inductors of the different wiring layers are connected through the through holes or the buried holes, so that the inductors of the different wiring layers are connected.

In fig. 6, the inductors in the different wiring layers with connection relation are in the same metal wiring structure, alternatively, the inductors in the different wiring layers with connection relation can be set to be in different metal wiring structures, for example, the inductor in one wiring layer is formed into a coil by spirally winding a metal wire on a plane in an arc shape, and the inductor in the other wiring layer is formed into a coil by spirally winding a metal wire on a plane in an angle of 45 °.

Alternatively, a plurality of inductors having a connection relationship may be disposed on the same wiring layer, for example, two of the inductors in fig. 6 may be disposed on the same wiring layer, and the remaining one inductor may be disposed on another wiring layer, where different inductors in the same wiring layer may use the same metal wiring structure, or may use different metal wiring structures.

Alternatively, the material of the metal wire in the inductor may be copper, or silver alloy, etc., and the cross section of the metal wire may be rectangular, or circular, etc.

In some embodiments of the present application, if the inductance value of the inductor is L, where the unit of L is uH, the multilayer coil coefficient is L ₀, the number of turns of the coil is W, the outer diameter of the coil is D, and the unit of D is cm, the inductance value of the inductor satisfies: l=l ₀×W²×D×10^-3, wherein when the cross section of the metal wire is rectangular, the thickness of the metal wire is 1-2oz, and the wire diameter of the metal wire is 8-20mil.

In this embodiment, the inductance calculation formula based on the multilayer coil is: l=l ₀×W²×D×10^-3, where L ₀ is a multilayer coil coefficient, W is the number of turns of the coil, D is the outer diameter of the coil, and as shown in fig. 13, the multilayer coil coefficient L ₀ is obtained from a numerical curve of the multilayer coil coefficient L ₀, t= (D-D0)/2, D0 is the inner diameter of the coil, where when the cross section of the metal wire is rectangular, the thickness of the metal wire is 1-2oz, and the wire diameter of the metal wire is 8-20mil.

In some embodiments of the present application, the passive element further includes a transformer, and/or a common-mode inductor, and/or a common-mode filter, where the transformer, the common-mode inductor, and the common-mode filter each include a primary coil and a secondary coil, the primary coil and the secondary coil adopt the same metal wiring structure as the inductor, and the primary coil and the secondary coil are disposed on the same wiring layer or on different wiring layers according to a preset turns ratio.

In this embodiment, the passive element further includes a transformer and/or a common-mode inductor and/or a common-mode filter, where the primary coil and the secondary coil adopt the same metal wiring structure as the inductor, that is, the primary coil and the secondary coil form a coil by adopting a metal wire to spiral around in a circular arc on a plane, or form a coil by adopting a metal wire to spiral around in a 45 ° on a plane, and the primary coil and the secondary coil may be disposed on the same wiring layer according to a preset turns ratio, or may be disposed on different wiring layers according to a preset turns ratio. It will be appreciated that the primary and secondary coils are of the same metal wiring structure for reliability.

Fig. 9 shows a top view of a transformer/common-mode inductor/common-mode filter formed by arranging a primary coil and a secondary coil on the same wiring layer in the embodiment of the utility model, wherein the primary coil and the secondary coil on the left side in fig. 9 are arranged on the same wiring layer, and all use metal wires to form coils in a spiral way at 45 degrees in a plane. The primary coil and the secondary coil on the right side in fig. 9 are arranged on the same wiring layer, and all use metal wires to form coils in a spiral way according to an arc on a plane.

Fig. 10 shows a side view of a transformer/common-mode inductor/common-mode filter formed by arranging a primary coil and a secondary coil on different wiring layers in an embodiment of the present utility model, wherein the primary coil and the secondary coil on the left side in fig. 10 are arranged on different wiring layers, and all use metal wires to form coils by spirally winding at 45 degrees on a plane. The primary coil and the secondary coil on the right side in fig. 10 are arranged on different wiring layers, and all adopt metal wires to form coils in a plane in a circular arc spiral surrounding manner, wherein the primary coils of the different wiring layers are connected through via holes or buried holes, and the secondary coils of the different wiring layers are also connected through the via holes or buried holes.

In some embodiments of the present application, the metal wiring structure of the capacitor includes two metal foils with the same shape as electrode plates, and the two electrode plates are oppositely disposed on different wiring layers, where if the capacitance value of the capacitor is C, the dielectric constant is epsilon, the surface area of the electrode plate is a, and the distance between the two electrode plates is d, the capacitance value of the capacitor satisfies: c=epsilon a/d.

In this embodiment, two metal foils with the same shape are used as electrode plates, and the two electrode plates are oppositely arranged on different wiring layers to form a capacitor, and the increase and decrease of the capacitance value can be realized by superposing different numbers of electrode plates on different wiring layers.

Alternatively, the shape of the metal foil may be rectangular or square, as shown by the upper metal wiring structure in fig. 7 and 8, and the design capacitance is large and easy to calculate. The shape of the metal foil can also be round or oval, and as shown in the lower metal wiring structure in fig. 7 and 8, the design wiring is simple and efficient, and the EMC effect is good. The metal foil may be copper or other metal. Different capacitors are connected through via holes or buried holes, so that the series connection of different capacitors is realized.

The calculation formula of the capacitance is as follows: c=ε×a/d, where C is the capacitance value, ε is the dielectric constant, a is the surface area of the electrode sheet, and d is the spacing between the two electrode sheets. Epsilon can be determined by the type of the base material of the PCB, and the electrode plate with corresponding area and the layer number of the electrode plate can be selected according to the required capacitance value.

In some embodiments of the present utility model, the corresponding RC filter circuit may be designed through the above-mentioned metal wiring structures of the resistor, the inductor and the capacitor, for example, fig. 11 shows a schematic diagram of an RC filter circuit in the embodiment of the present utility model, R, L, T, C in fig. 11 respectively represents the resistor, the inductor, the transformer and the capacitor, and the corresponding metal wiring structures are adopted to design the RC filter circuit in the PCB board, so as to obtain the wiring structure shown in fig. 12, and in fig. 12, R2 and R3 are connected in parallel and then connected in series with R1. It should be understood that the wiring structure shown in fig. 12 is only one specific implementation manner in the embodiment of the present utility model, and those skilled in the art may flexibly use other wiring structures according to actual needs.

The PCB in the embodiment of the application comprises: the wiring layers are sequentially stacked; the passive element adopts a metal wiring structure corresponding to the type of the passive element, the passive element is arranged on at least one wiring layer, the metal wiring structure in the PCB is used as the passive element, the standard passive element adopting the PCB layout structure to replace an entity is realized, the reliability of the passive element is improved, the after-market problem caused by the element quality problem is reduced, and meanwhile, the performance of the passive element can be changed by adjusting the metal wiring structure of the passive element, so that the optimal design of a more efficient matching circuit is realized or the EMC problem is solved, the customizable of the element is realized, and the complexity of design work is reduced.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature, and in the description of the utility model, "a plurality" means two or more, unless otherwise specifically and clearly defined.

In the present utility model, unless explicitly specified and limited otherwise, the terms "access", "connected", and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present utility model. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although embodiments of the present utility model have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the utility model, and that variations, modifications, alternatives, and variations may be made in the above embodiments by those skilled in the art without departing from the spirit and principles of the utility model.

Claims (10)

1. A PCB board, comprising:

the wiring layers are sequentially stacked;

and the passive element is structurally characterized by adopting a metal wiring structure corresponding to the type of the passive element, and the passive element is arranged on at least one wiring layer.

2. The PCB of claim 1, wherein there is a connection between passive components in different wiring layers, connected by vias or buried vias.

3. The PCB of claim 1, wherein the passive component is a combination comprising any one or more of a resistor, an inductor, and a capacitor.

4. The PCB of claim 3, wherein the metal wiring structure of the resistor includes wiring in a circular arc using metal wires or wiring in a long distance of 45 ° using metal wires.

5. The PCB of claim 4, wherein if the resistance of the resistor is R, the conductivity of the metal line is ρ, the cross-sectional area of the metal line is a, and the length of the metal line is L, the resistance of the resistor satisfies: r=ρ (L/a), wherein when the cross section of the metal wire is rectangular, the thickness of the metal wire is 1-2oz, and the wire diameter of the metal wire is 8-20mil.

6. The PCB of claim 3, wherein the metal wiring structure of the inductor includes forming a coil by spirally winding a metal wire in a circular arc on a plane or forming a coil by spirally winding a metal wire in a 45 ° on a plane.

7. The PCB of claim 6, wherein if the inductance of the inductor is L, the unit of L is uH, the multilayer coil coefficient is L ₀, the number of turns of the coil is W, the outer diameter of the coil is D, and the unit of D is cm, the inductance of the inductor satisfies: l=l ₀×W²×D×10^-3, wherein when the cross section of the metal wire is rectangular, the thickness of the metal wire is 1-2oz, and the wire diameter of the metal wire is 8-20mil.

8. The PCB of claim 6, wherein the passive component further comprises a transformer, and/or a common-mode inductor, and/or a common-mode filter, the transformer, the common-mode inductor, and the common-mode filter each comprise a primary coil and a secondary coil, the primary coil and the secondary coil adopt the same metal wiring structure as the inductor, and the primary coil and the secondary coil are disposed on the same wiring layer or on different wiring layers according to a preset turns ratio.

9. The PCB board of claim 3, wherein the metal wiring structure of the capacitor includes two metal foils with the same shape as electrode pads, the two electrode pads are disposed opposite to each other in different wiring layers, and if the capacitance value of the capacitor is C, the dielectric constant is epsilon, the surface area of the electrode pad is a, and the distance between the two electrode pads is d, the capacitance value of the capacitor satisfies: c=epsilon a/d.

10. An automotive electronic control module, characterized in that it comprises a PCB board according to any one of claims 1-9.