Mutually shielded printed circuit board assemblies

Abstract

An electronic assembly includes a first printed circuit board (PCB), a second PCB, and a ground shield. The first PCB includes a first plurality of electronic components and a first conductive layer. The second PCB includes a second plurality of electronic components and a second conductive layer. The ground shield is electrically connected between the first conductive layer of the first PCB and the second conductive layer of the second PCB to electrically connect the first PCB and the second PCB. The first PCB and the second PCB are arranged in a stacked manner so that the first conductive layer and the second conductive layer mutually shield at least one of the first plurality of electronic components and at least one of the second plurality of electronic components from electromagnetic interference.

Description

[0001] background

[0002] Electromagnetic (EM) radiation can be emitted from various electronic sources. Such EM radiation can prevent electronic devices from operating properly due to electromagnetic interference (EMI). To prevent EMI, an EMI shield can be electrically connected to a printed circuit board (PCB) to block EM radiation. Sometimes one or more EMI shields may be required to cover the entire PCB or a portion of the PCB. Summary of the invention

[0003] This summary is provided to introduce in a simplified form a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that solve any or all of the disadvantages mentioned in any part of this disclosure.

[0004] An electronic assembly includes a first printed circuit board (PCB), a second PCB, and a ground shield. The first PCB includes a first plurality of electronic components and a first conductive layer. The second PCB includes a second plurality of electronic components and a second conductive layer. The ground shield is electrically connected between the first conductive layer of the first PCB and the second conductive layer of the second PCB to electrically connect the first PCB to the second PCB. The first PCB and the second PCB are arranged in a stacked manner so that the first conductive layer and the second conductive layer mutually shield at least one of the first plurality of electronic components and at least one of the second plurality of electronic components from electromagnetic interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1A and 1B An example electronic assembly is schematically illustrated that includes mutually shielded printed circuit boards (PCBs) electrically connected to a common ground shield.

[0007] Figure 2A and 2B Another example electronic assembly is schematically illustrated and includes mutually shielded PCBs electrically connected to a common ground shield including a plurality of surface mountable electronic components and / or surface mountable metal structures positioned around the entire perimeter.

[0008] Figure 3A and 3B Another example electronic assembly is schematically illustrated and includes mutually shielded PCBs electrically connected to a common ground shield including a plurality of ground contacts, the common ground shield including surface mountable electronic components and surface mountable metal structures located around different portions of the perimeter and other ground structures or materials electrically connecting the two PCBs.

[0009] Figure 4 Another example electronic assembly is schematically illustrated and includes a plurality of surface-mountable electronic components electrically connected between ground planes of two mutually shielded PCBs.

[0010] Figure 5 Another example electronic assembly is schematically illustrated and includes a plurality of surface-mountable electronic components electrically connected between ground planes of two mutually shielded PCBs.

[0011] Figure 6 Another example electronic assembly is schematically illustrated in which a PCB cooperates with two additional PCBs electrically connected on the same side of the PCB to provide mutual shielding.

[0012] Figure 7 Another example electronic assembly is schematically illustrated in which a PCB cooperates with two additional PCBs electrically connected on opposite sides of the PCB to provide mutual shielding.

[0013] Figure 8 is a flow chart depicting aspects of an example method for producing an electronic assembly.

[0014] Detailed Description

[0015] Certain electronic components mounted on a printed circuit board (PCB) may generate signal noise that may interfere electromagnetically with other nearby radio components, thereby degrading the performance of the radio components. This form of electromagnetic interference may be referred to as desensitization or "desensitization," in which a radio receiver is unable to receive radio signals that it might be able to receive in the absence of interference. For example, the desensitization of a radio component may be caused by a nearby electronic component having a noise signal of similar frequency, which may overload the radio and thus prevent the desired signal from being fully received. Other situations may occur in which sensitive electronic components on a PCB may be protected from noise generated in the environment or elsewhere on the device. In addition, the device may need to comply with electromagnetic compatibility (EMC) regulations, which specify the maximum and minimum noise that a device can emit, or the maximum and minimum noise that can be operated in the presence of, respectively. In order to mitigate desensitization and / or other electromagnetic interference effects, at least some of the electronic components on the PCB may be encapsulated by some form of electromagnetic interference (EMI) shielding to electromagnetically isolate the electronic components. As an example, an EMI shield includes a metal housing surrounding the electronic components on the PCB. The EMI shield may be electrically connected to the ground plane of the PCB to provide EMI shielding for the electronic components.

[0016] In an electronic assembly using two or more PCBs in collaboration, the two or more PCBs can be electrically connected to each other through one or more electrical connectors. In past solutions, each PCB would have a separate EMI shield or multiple EMI shields. Using a separate EMI shield for each PCB may result in an increase in the size of the PCB, which in turn may result in an increase in the length of the electrical connector electrically connected between the PCBs. In an example where the PCBs are arranged side by side, the electrical connector may have to extend beyond the perimeter formed by the EMI shield in order to reach the shielded electronic components (or another electrical connection point - for example, a ground plane, a power plane) within the EMI shield. In this case, the distance between the edge of the PCB and the electronic component may be increased to allow the EMI shield to be located between them, which may be the reason for increasing the length of the electrical connector. In another example where the PCBs are arranged in a stacked manner, the height of the EMI shield may be greater than the height of any electronic component on the PCB. In this case, the height of the EMI shield may be the reason for increasing the length of the electrical connector.

[0017] Additionally, when interconnects are made between two PCBs, various EMI issues may arise. High-speed signals passing through interconnects are often shielded using more complex, more expensive connectors or using mechanical shielding that encapsulates the interconnects. The number of interconnects used may be limited by cost or EMI requirements. If lower cost connectors can be used without EMI issues, multiple connectors can be used in multiple locations, which will reduce design constraints and / or costs. Additionally, the length and location of electrical connectors may limit the signal integrity and speed of signals that can be transmitted between the PCBs, as well as present PCB trace routing challenges. Attempting to add more electrical connectors to simplify trace routing may have a negative impact on EMI.

[0018] Therefore, the present specification relates to an electronic assembly that solves the above-mentioned problems. The electronic assembly may include a first PCB, a second PCB, and a ground shield electrically connected between the conductive layers (e.g., ground planes) of the first and second PCBs. The first PCB includes a first plurality of electronic components. The second PCB includes a second plurality of electronic components. The first PCB and the second PCB may be arranged in a stacked manner so that the first conductive layer (e.g., ground plane) of the first PCB and the second conductive layer (e.g., ground plane) of the second PCB cooperate with the ground shield to mutually shield at least one of the first plurality of electronic components and at least one of the second plurality of electronic components to provide isolation from an internal shielding area to the outside. Such isolation may include suppressing noise caused by the electronic components from leaving the internal shielding area, or may include preventing EMI from the environment from entering the internal shielding area.

[0019] In some examples, the ground shield can surround the entire perimeter of the two PCBs to provide perimeter EMI shielding for the first plurality of electronic components and the second plurality of electronic components. In some examples, the ground shield can extend at least partially around one or more electronic components to provide EMI shielding for the one or more components. In some examples, the ground shield can include a perimeter ground shield and additional ground shield elements inside the perimeter to shield or isolate different electronic components.

[0020] Such electronic assemblies can improve the size and cost issues of the above-mentioned previous solutions. Specifically, by replacing two separate EMI shields with mutual shielding provided by the conductive layers of the two PCBs and a single common ground shield, the distance (i.e., height) between the two PCBs can be reduced. This in turn can reduce the length of the electrical connector electrically connected between the two PCBs. In addition, in such electronic assemblies, the electrical connector can be electrically connected between the PCBs within the internal shielding area. This allows the use of a low-cost unshielded electrical connector. Additionally, the electrical connector can be electrically connected between the PCBs at any position within the internal shielding area. This allows layout design flexibility, which can increase the integration density of electronic components on the PCB, which can reduce the occupied area of ​​the PCB. In addition, such design flexibility allows the use of additional electrical connections between the PCBs as needed, because a low-cost unshielded electrical connector can be used for such connections, and because not all traces / connections must be fed through a single shielded electrical connector.

[0021] In some implementations, the ground shield may include one or more surface-mountable electronic components or surface-mountable mechanical structures electrically connected between the first PCB and the second PCB. Such surface-mountable electronic components or surface-mountable mechanical structures may be configured to provide EMI shielding to at least some of the electronic components of the first and second PCBs. In some examples, such surface-mountable electronic components or surface-mountable mechanical structures may be commercial electronic components with standardized sizes and shapes, which are configured to be installed on the PCB in an automated manner using commercial machinery (e.g., a pick-and-place machine). By using such production methods, the time and cost of producing such electronic assemblies may be reduced. In addition, in some cases, in addition to EMI shielding, surface-mountable electronic components may also provide additional benefits. In some examples, surface-mountable electronic components may include decoupling, filtering or matching components, which may be electrically connected between the conductive traces of the two PCBs. Decoupling, filtering or matching components may be used to shunt or filter signals or noise, filter or adjust signals, or for impedance matching of signals sent via conductive traces.

[0022] Figure 1A and 1BAn example electronic assembly 100 is schematically illustrated and includes a first PCB 102 and a second PCB 104 electrically connected to a common ground shield 106 . Figure 1A The second PCB 104 is shown spaced apart from the first PCB 102 to expose the ground shield 106 and the first plurality of electronic components 108 located on the surface 110 of the first PCB 102. In addition, the second plurality of electronic components 112 are located on the second surface 114 of the second PCB 104. The first and second PCBs 102 and 104 are arranged in a stacked manner such that the surface 110 is opposite to the surface 114.

[0023] Any suitable type of electronic components may be mounted on the surface of the first PCB 102 or the second PCB 104. Non-limiting examples of electronic components that may be mounted on the surfaces of the first and second PCBs 102, 104 include: passive circuit components (e.g., capacitors, resistors, inductors), active circuit components (e.g., diodes, transistors), electromechanical components, optoelectronic components, display components, audio components, sensor components, radio frequency (RF) components, integrated circuits (ICs), systems on a chip (SoCs), and power components. In some examples, at least some of the plurality of electronic components 108 and / or 112 may be commercially available surface mountable or surface mount technology (SMT) type components. In some examples, at least some of the plurality of electronic components 108 and / or 112 may optionally be through-hole type components.

[0024] A plurality of conductive traces 116 may extend along the surface 110 of the first PCB 102. The plurality of conductive traces 116 may be configured to electrically connect the plurality of electronic components 108 to various other electronic components and / or other circuit systems (e.g., power, ground) on the first PCB 102. The plurality of conductive traces 116 may be formed of any suitable conductive material. As an example, the conductive traces 116 include copper. Any suitable number of conductive traces 116 may be arranged on the surface 110 of the first PCB 102 according to any suitable layout design. In addition, in some examples, one or more of the conductive traces 116 may be connected to different non-surface layers of the first PCB 102. Similarly, the second PCB 104 may include a plurality of conductive traces (not shown). In some examples, the electronic assembly may include an electrical connector that is electrically connected between the conductive traces on the first and second PCBs 102, 104.

[0025] The board-to-board interconnect 118 is mounted on the surface 110 of the first PCB 102. The interconnect 118 can be configured to be electrically connected to a corresponding interconnect (not shown) on the second PCB 104 to enable signals to be sent between the two PCBs. The interconnect 118 can take any suitable form and can be electrically and / or mechanically connected to the corresponding interconnect on the second PCB 104 in any suitable manner. As a non-limiting example, the interconnect can be a snap fit, a spring fit, or a press fit with the corresponding interconnect to connect the two PCBs. In the depicted example, the interconnect 118 is located at the center of the first PCB 102. It should be understood that the interconnect can be placed at any suitable position on the first PCB 102. In some examples, two or more interconnects can be electrically connected between the two PCBs 102, 104.

[0026] The first and second PCBs 102, 104 can take any suitable form. More specifically, the size and shape of the first and second PCBs 102, 104 can be adjusted to accommodate the plurality of electronic components 108, 112 and the plurality of conductive traces 116. The first and second PCBs 102, 104 can include any suitable number of different layers, including conductive layers (e.g., ground layers, power layers) and non-conductive / substrate layers (e.g., surface layers, insulating layers). In some examples, either of the first and second PCBs 102, 104 can be non-rigid or flexible.

[0027] Figure 1B A second PCB 104 is schematically shown electrically connected and mechanically attached to the first PCB 102 via a ground shield 106. The ground shield 106 may be electrically connected between a first conductive layer of the first PCB 102 and a second conductive layer of the second PCB 104. The first and second PCBs 102, 104 may be arranged so that the conductive layers, for example, ground planes (not shown) of the first and second PCBs 102, 104 provide mutual EMI shielding. Specifically, the conductive layers in the first PCB 102 may provide a lower EMI shielding layer and the conductive layers in the second PCB 104 may provide an upper shielding layer. The lower shielding layer of the first PCB 102, the upper shielding layer of the second PCB 104, the surrounding ground shield 106, and appropriate PCB through-holes together form an internal shielding area that electromagnetically isolates the electronic components 108, 112 and the traces 116 located therein. The ground shield 106 may be used for a number of additional purposes, such as as a heat sink, a base, or a structural component that provides mechanical support.

[0028] The electronic assembly may optionally include features that promote heat dissipation of the electronic assembly. In some implementations, the ground shield may be porous or may have holes to allow air to flow in the space between the PCBs. In some implementations, the electronic assembly 108 or 112 may be thermally connected to the relative PCB through mechanical contact or thermal interface materials. The relative PCB may have multiple through holes or copper layers to spread or dissipate heat from the electronic assembly. In some implementations, multiple holes may be formed in the relative PCB and multiple heat sinks may be directly attached to the electronic assembly 108 or 112. In some implementations, holes may be formed in the PCB to allow airflow through the PCB. In some implementations, thermal potting materials may fill the space between the PCBs. In some implementations, the ground shield may be a steam chamber and may be configured to provide dual shielding and cooling functions.

[0029] In some examples, the ground plane may extend substantially beneath the entire surface of the PCBs 102, 104. In some examples, the first and second PCBs 102, 104 may include a partial or non-continuous layer that occupies only a portion of the total area of ​​the PCBs. In some such examples, the first and second PCBs 102, 104 may provide mutual shielding in portions of the two PCBs having overlapping ground planes.

[0030] In the depicted example, the ground shield 106 extends continuously around the perimeter of the first and second PCBs 102, 104 to provide EMI shielding for all electronic components 108, 112 and conductive traces 116 on the surfaces of the PCBs 102, 104. In some examples, the ground shield 106 may only surround some of the electronic components 108, 112 and / or conductive traces 116 to form a shielding sub-region between the two conductive layers of the PCBs 102, 104. In some such examples, other electronic components not positioned within the shielding sub-region may be partially shielded or unshielded. In some implementations, the ground shield may include a perimeter ground shield and additional internal grounding elements that at least partially surround a separate electronic component or group of electronic components to isolate the electronic component from other electronic components within the internal shielding region. In other words, the ground shield may include multiple different internal shielding regions that are isolated from each other to strategically prevent undesirable resonance or coupling within the structure and / or provide additional grounding in some regions.

[0031] The ground shield 106 may include any suitable conductive material, such as metal, conductive foam, conductive fabric on foam, conductive elastomer, metal base or heat sink, surface mountable metal structure, any other suitable conductor, or a combination thereof. The metal ground shield may be made in any suitable manner. For example, the metal ground shield may be machined, stamped or drawn. In some examples, the ground shield 106 may include metallized plastic or resin. In some examples, the ground shield 106 may include an aluminum base. The ground shield 106 may be electrically connected and mechanically attached to the first and second PCBs 102, 104 in any suitable manner. As an example, the ground shield 106 may be electrically connected and mechanically attached to the first and second PCBs 102, 104 via a metal clip connected to the ground plane of each of the PCBs 102, 104. The metal clip may hold the ground shield 106 in place via a tension fit or a spring force fit. As another example, the ground shield 106 may be electrically connected and mechanically attached to the first and second PCBs 102, 104 via solder. As discussed in further detail below, in some implementations, different types of solders optionally may be used to connect different components to facilitate construction of electronic assembly 100 .

[0032] In some examples, electronic components on the PCB may be a source of EM radiation or coupling, and the internal shielding area may be configured to encapsulate the electronic components to contain the EM radiation or coupling at the source. In other examples, electronic components on the PCB may be susceptible to EMI, and the internal shielding area may be configured to encapsulate the electronic components to block EM radiation or coupling from reaching the electronic components.

[0033] Note that the electronic assembly depicted includes only electronic components located on the inner surface of the PCB. It should be understood that additional electronic components may also be optionally located on the outer surface of the PCB. In some of these examples, there may be an internal ground plane layer with through-hole openings inside the PCB that allow some signals to pass between the outer surface and the inner surface through the PCB. In some such examples, decoupling capacitors or other decoupling, filtering, or matching components may be placed at these locations on the PCB to shunt noise to the ground plane and prevent it from escaping the shielded area. In some examples, if the application does not require high shielding effectiveness, decoupling, filtering, or matching components may not be used at such locations.

[0034] Figure 2A and 2B Another example electronic assembly 200 is schematically illustrated and includes a first PCB 202 and a second PCB 204 electrically connected to a common ground shield 206 including a plurality of commercially available surface mountable electronic components and / or surface mountable metal structures 207 around the entire perimeter of the PCBs 202 , 204 . Figure 2A A second PCB 204 is shown spaced apart from the first PCB 202 to expose a ground shield 206 and a first plurality of electronic components 208 located on a surface 210 of the first PCB 202. In addition, a second plurality of electronic components 212 are located on a second surface 214 of the second PCB 204. A plurality of conductive traces 216 may extend along the surface 210 of the first PCB 202. The plurality of conductive traces 216 may be configured to electrically connect the plurality of electronic components 208 to various other electronic components and / or other circuit systems (e.g., power, ground) on the first PCB 202. Similarly, the second PCB 204 may include a plurality of conductive traces (not shown). The first and second PCBs 202 and 204 are arranged in a stacked manner such that the surface 210 is opposite to the surface 214.

[0035] Figure 2B The second PCB 204 is schematically shown to be electrically connected and mechanically attached to the first PCB 202 via a plurality of commercially available surface-mountable electronic components and / or surface-mountable metal structures 207 of a ground shield 206. The first and second PCBs 202, 204 can be arranged so that the conductive layers, for example, the ground planes (not shown) of the first and second PCBs 202, 204 provide mutual EMI shielding. In addition, the first and second PCBs 202, 204, in cooperation with the plurality of commercially available surface-mountable electronic components and / or surface-mountable metal structures 207 forming the ground shield 206, can jointly form an internal shielding area that electromagnetically isolates the electronic components 208, 212 and the traces 216 located therein. The ground shield 206 can be used for a number of additional purposes, such as as a heat sink, a base, or a structural component that provides mechanical support.

[0036] In some implementations, ground shield 206 can be used to dissipate heat using separate surface-mountable electronic components and / or surface-mountable metal structures 207. Heat can be dissipated via thermal conduction, convection, or radiation. Multiple surface-mountable electronic components and / or surface-mountable metal structures 207 can be added in the interior area between PCBs to improve heat dissipation.

[0037] Each commercial surface-mountable electronic component and / or surface-mountable metal structure 207 can provide an electrical connection between a first conductive layer of the first PCB 202 and a second conductive layer of the second PCB 204, such that the plurality of commercial surface-mountable electronic components and / or surface-mountable metal structures 207 collectively form a ground shield 206. In some examples, one or more of the commercial surface-mountable electronic components and / or surface-mountable metal structures 207 can include a zero-ohm resistor that provides an electrical connection between the PCBs 202, 204. In some examples, the commercial surface-mountable electronic components and / or surface-mountable metal structures 207 can include other electronic components as discussed in further detail herein.

[0038] Typically, commercial surface-mountable electronic components are mounted on a single PCB. In such cases, the commercial surface-mountable electronic components are oriented "horizontally" with both ends electrically connected to different connection points on the same PCB. In contrast, each of the plurality of commercial surface-mountable electronic components and / or surface-mountable metal structures 207 included in the ground shield 206 is oriented "vertically" at the ends and connected between different PCBs.

[0039] Commercial surface-mountable electronic components and / or surface-mountable metal structures 207 may have standardized sizes and dimensions. Such commercial surface-mountable electronic components may be of any suitable size and / or package type (e.g., 0402 or 0201). By using commercial surface-mountable components in this manner, ground shield 206 may have a substantially uniform height and thickness. In addition, electronic assembly 200 may be constructed using commercial manufacturing equipment such as a pick-and-place machine to electrically connect commercial surface-mountable electronic components or surface-mountable metal structures 207 to a PCB. In other words, by using commercial manufacturing equipment, the production cost of electronic assembly 200 may be reduced because the electrical and mechanical properties of the components have been designed, tested, and mass-produced.

[0040] Note that commercially available surface-mountable electronic components and / or surface-mountable metal structures are one example of the type of electronic components that can be used to form the ground shield 206, and other types of electronic components can be used in other examples. In addition, other assembly methods / techniques can be used to produce such electronic assemblies.

[0041] Commercial surface-mountable electronic components and / or surface-mountable metal structures 207 may be electrically connected and / or mechanically attached between the first PCB 302 and the second PCB 204 using any suitable conductive material / technique. In one example, the commercial surface-mountable electronic components and / or surface-mountable metal structures 207 may be soldered between the first PCB 202 and the PCB 204. In a specific example, the commercial surface-mountable electronic components and / or surface-mountable metal structures 207 may first be connected to the first PCB 202 via high-temperature solder soldering. Then, the commercial surface-mountable electronic components and / or surface-mountable metal structures 207 may be soldered to the second PCB 204 via reflow solder having a lower melting point than the high-temperature solder. This may allow the entire first PCB 202 and the mounted commercial surface mountable electronic components and / or surface mountable metal structures 207 forming the ground shield 206 to be reflowed in an oven to solder it to the second PCB 204 without high temperature solder melting.

[0042] Additionally or alternatively, in some examples, commercially available surface-mountable electronic components and / or surface-mountable metal structures 207 may be electrically connected and / or mechanically attached in different ways. Such examples may include epoxy, welding, friction or mechanical fit, spring force, and adhesives.

[0043] In some implementations, at least some of the commercially available surface-mountable electronic components and / or surface-mountable metal structures 207 forming the ground shield 206 may be electrically connected to other conductors on either surface of the PCBs 202, 204 other than the ground plane. As one example, the commercially available surface-mountable electronic components and / or surface-mountable metal structures may be electrically connected between power planes of the PCBs 202, 204. As another example, the commercially available surface-mountable electronic components and / or surface-mountable metal structures may be electrically connected between conductive traces on the surface of the PCBs 202, 204. As yet another example, the commercially available surface-mountable electronic components and / or surface-mountable metal structures may be electrically connected between another conductor (e.g., any copper sheet) exposed on the surface of the PCBs 202, 204.

[0044] It should be noted that when commercial surface-mountable electronic components and / or surface-mountable metal structures are electrically connected between conductive traces on the surface of PCBs 202, 204, it can act as a low-cost interconnect. This is different from existing implementations in important ways. First, the interconnect is very low-cost, for example, if a zero-ohm resistor is used, the cost may be only a fraction of a penny. Second, it takes up very little PCB board space because it only requires surface-mounted components with a small footprint. Third, any radiated or coupled EM noise is contained between the PCBs and does not generate EMI that extends outside the PCBs, achieving the shielding effect of mutual PCB shielding. Fourth, due to the first three benefits, it allows a large number of interconnects to be placed anywhere on the PCB, which allows more flexible routing options, potentially requires fewer PCB layers and lower-cost PCBs, and achieves high-density design, so that more data can be passed from one PCB to another PCB and / or allows more integrated circuits to be more closely integrated. These are potential advantages compared to existing non-mutually shielded PCBs, which are not connected together by commercial surface-mountable electronic components and / or surface-mountable metal structures.

[0045] Active electronic components (e.g., transistors, ICs) 208, 212 on the first or second PCB 202, 204 may operate at high frequencies or fast clock signals, which may generate noise harmonics or broadband noise spectra. Under certain conditions (such as impedance mismatch, proximity, or conductor geometry), electric and magnetic fields may radiate into space or couple to other electronic components. In addition, the electronic components 208, 212 may be connected to the power supply through conductive traces and / or other conductors with finite resistance and inductance. If the current drawn by the active electronic components changes, the voltage drop from the power supply to the device will also change due to these impedances. If multiple active devices share a common path to the power supply, the current drawn by one component may produce a large enough voltage change to affect the operation of other components-such as voltage spikes or ground bounce-so the state change component of one electronic component can be coupled to other electronic components through the common impedance of the power supply in the form of signal noise. In some cases, the electronic components may not generate noise, but it is necessary to optimize the impedance matching with the electronic components so that signal loss can be minimized. In other cases, noise may not be present, but filtering or conditioning of the signal may be required, such as a bandpass filter, lowpass filter, or duplexer.

[0046] To address these issues, in some implementations, one or more of the commercially available surface-mountable electronic components 207 may be decoupling, filtering or matching components. In some examples, decoupling, filtering or matching components may be electrically connected between conductive traces on each PCB 202, 204. Decoupling, filtering or matching components connected between conductive traces can help prevent the radiation or coupling of electromagnetic interference caused by component frequency components or rapidly changing power supply currents. In particular, decoupling, filtering or matching components can provide a bypass path for transient currents to flow through a return path, rather than allowing transient currents to flow through the common impedance of the conductive traces. In this case, the decoupling, filtering or matching components can play a dual role of being configured to filter or match signals or shunt noise from conductive traces, and provide electrical and mechanical connections between the first PCB 202 and the second PCB 204. In addition, the electrical connection provided by the decoupling, filtering or matching components can help form an internal shielding area between the PCBs 202, 204. In some examples, decoupling, filtering, or matching components may be electrically connected between other conductors of PCBs 202 , 204 , including power planes and ground planes.

[0047] In some cases, the decoupling, filtering or matching component may be configured to act as a filter. As an example, the decoupling, filtering or matching component may be configured to act as a low-pass filter. Such decoupling, filtering or matching components may be configured to filter any suitable frequency range. In some examples, different decoupling, filtering or matching components may be configured to filter different frequency ranges according to the connection type (e.g., to a trace, a ground plane, a power plane) and / or other factors. In addition, the decoupling, filtering or matching component may be configured to match the impedance of the trace when applicable. In some cases, the decoupling, filtering or matching component may be configured to act as a ground reference for an electronic component, and shielding may be considered a secondary function. In some cases, the decoupling, filtering or matching component may be used as a DC block.

[0048] Any suitable type of decoupling, filtering, or matching component may be integrated into the ground shield 206 and electrically connected between the PCBs 202, 204. For example, the decoupling, filtering, or matching component may include a decoupling capacitor, an inductor, a multi-element filter (e.g., "L", "T", "π" topology), or another type of filter or signal conditioning component such as a duplexer, circulator, combiner, etc.

[0049] The ground shield 206 may include any suitable combination of different types of commercially available surface-mountable electronic components and / or surface-mountable metal structures 207. In some examples, all of the commercially available surface-mountable electronic components and / or surface-mountable metal structures 207 may be the same type of electronic components (e.g., zero-ohm resistors). In some examples, different types of electronic components may be positioned according to the surface layout of the PCBs 202, 204. For example, a zero-ohm resistor may be electrically connected between perimeter ground planes of the PCBs 204, 204 at one portion of the ground shield 206, and a decoupling, filtering, or matching component may be electrically connected between conductive traces of the PCBs 202, 204 at another portion of the ground shield 206. Any suitable type of commercially available surface-mountable electronic components and / or surface-mountable metal structures may be positioned at any suitable portion of the ground shield 206, depending on the type of connection and functionality required of the electronic components.

[0050] Figure 3A and 3B Another example electronic assembly 300 is schematically illustrated and includes a first PCB 302 and a second PCB 306 electrically connected to a common ground shield 304 including a plurality of commercially available surface mountable electronic components and / or surface mountable metal structures 307 and / or other conductive materials 309 . Figure 3A A second PCB 304 is shown spaced apart from the first PCB 302 to expose a ground shield 306 and a first plurality of electronic components 308 located on a surface 310 of the first PCB 302. In addition, the second plurality of electronic components 312 are located on a second surface 314 of the second PCB 304. A plurality of conductive traces 316 may extend along the surface 310 of the first PCB 302. The plurality of conductive traces 316 may be configured to electrically connect the plurality of electronic components 308 to various other electronic components and / or other circuit systems (e.g., power, ground) on the first PCB 302. Similarly, the second PCB 304 may include a plurality of conductive traces (not shown). The first and second PCBs 302 and 304 are arranged in a stacked manner such that the surface 310 is opposite to the surface 314.

[0051] The ground shield 306 may include a plurality of commercial surface-mountable electronic components and / or surface-mountable metal structures 307, which may be intelligently positioned around the perimeter to provide specific functions between specific connections. For example, decoupling, filtering or matching components may be positioned around the perimeter to align with the conductive traces of the PCBs 302, 304 and electrically connect therebetween. As another example, commercial surface-mountable electronic components and / or surface-mountable metal structures may be positioned around the perimeter to align with the power planes of the PCBs 302, 304 and electrically connect therebetween. Another example is that if the conductive material 309 is a heat sink, a base or structural mechanical component and a plurality of commercial surface-mountable electronic components and / or surface-mountable metal structures 307 are used to fill any remaining gaps or voids. Another example is that if the conductive material 309 requires a large escape zone, such as if it is a conductive foam, and a plurality of commercial surface-mountable electronic components or surface-mountable metal structures 307 are placed in an area where there is not enough space to accommodate the escape zone. In another example, the conductive material 309 forms a perimeter and a plurality of commercial surface-mountable electronic components or surface-mountable metal structures 307 form additional ground shield elements within the perimeter. The commercial surface-mountable electronic components and / or surface-mountable metal structures 307 may be intelligently positioned at any portion of the ground shield 306 to provide any suitable function.

[0052] In addition, other conductive materials 309 can be connected between the ground planes of PCBs 302, 304 in a portion of the perimeter (this portion of the perimeter can include a portion of the perimeter where no commercially available surface-mountable electronic components 307 are present) to provide EMI shielding substantially around the entire perimeter, which can include a portion of the perimeter interior of the PCBs 302, 304. In some examples, other conductive materials 309 can provide structural rigidity to ensure that the two PCBs 302, 304 remain parallel and / or separate. In some examples, other conductive materials 309 can be non-rigid or flexible. In some such examples, the PCBs and / or surface-mountable electronic components can also be non-rigid or flexible. Other conductive materials 309 can include any suitable type of conductive material, including stamped or drawn metal, conductive foam, conductive elastomer, conductive fabric on foam, conductive non-woven fabric, cast or machined aluminum, or other conductive materials. Other conductive materials 309 can be electrically connected to the ground planes of PCBs 302, 304 in any suitable manner. Such examples may include epoxy, welding, friction or mechanical fit (e.g., via metal clips), spring force, and adhesives. There may be multiple layers of different conductive materials, for example, one such stacked layer is conductive adhesive, conductive foam, conductive adhesive. Many other combinations are also possible.

[0053] A plurality of commercial surface-mountable electronic components and / or surface-mountable metal structures 307 can be integrated with other conductive materials 309 in the ground shield 306 in any suitable manner. In the depicted example, the other conductive materials 309 form a sidewall or perimeter fence having a cutout or slot 318 configured to accommodate the commercial surface-mountable electronic components and / or surface-mountable metal structures 307. The size of the slots 318 can be adjusted to minimize the distance between the other conductive materials 309 and the commercial surface-mountable electronic components and / or surface-mountable metal structures 307 so as to maintain the shielding effect of the ground shield 306 and reduce parasitic inductance. In other words, the commercial surface-mountable electronic components and / or surface-mountable metal structures 307 can substantially fill the space of the slots to maintain shielding along the sidewalls and reduce parasitic inductance. In another example, the commercial surface-mountable electronic components and / or surface-mountable metal structures 307 can be confined within the multi-layer sidewalls of the ground shield 306.

[0054] The electronic assembly 300 may include interior walls or compartments. For example, an internal shielding compartment 320 may be formed around an integrated circuit 322 to isolate the integrated circuit from other electronic components on the first PCB 302. Commercial surface-mountable electronic components and / or surface-mountable metal structures 307 may occupy slots in these internal compartment walls in the same manner as the external ground shield 306 to provide the same functions. For example, commercial surface-mountable electronic components and / or surface-mountable metal structures 324 may be electrically connected to conductive traces connected between the integrated circuit 322 and an adjacent integrated circuit located outside the internal shielding compartment 320. In one example, the commercial surface-mountable electronic components and / or surface-mountable metal structures 324 may provide decoupling, filtering, or matching functions of the conductive traces.

[0055] Figure 3B The second PCB 304 is schematically shown to be electrically connected and mechanically attached to the first PCB 302 via a plurality of commercial surface-mountable electronic components and / or surface-mountable metal structures 307 and other conductive materials 309 of a ground shield 306. The first and second PCBs 302, 304 can be arranged so that the conductive layers, for example, the ground planes (not shown) of the first and second PCBs 302, 304 provide mutual EMI shielding. In addition, the first and second PCBs 302, 304, in cooperation with the plurality of commercial surface-mountable electronic components and / or surface-mountable metal structures 307 and other conductive materials 309 forming the ground shield 306, can jointly form an internal shielding area that electromagnetically isolates the electronic components 308, 312 and the traces 316 located therein.

[0056] Figure 4 and Figure 5 Aspects of different example electronic assemblies having a common ground shield electrically connected between two mutually shielded PCBs are shown. In particular, the figures show partial cross-sectional views of the electronic assemblies.

[0057] Figure 4 An example electronic assembly 400 is shown. The depicted view is from Figure 2A However, line AA is provided only as a reference system because electronic assembly 400 is different from Figure 2A . The electronic assembly 400 includes a first PCB 402, which includes a plurality of substrate layers 404 (e.g., a first layer 404A, a second layer 404B, and a third layer 404C). A ground plane 406 is located between the first layer 404A and the second layer 404B. A power plane 408 is located between the second layer 404B and the third layer 404C. An outer conductive layer 410 is located below the third layer 404C.

[0058] The electronic assembly 400 includes a second PCB 412 opposite to the first PCB 402. The second PCB 412 includes a plurality of substrate layers 414 (e.g., a first layer 414A, a second layer 414B, and a third layer 414C). A ground plane 416 is located between the first layer 414A and the second layer 414B. A power plane 418 is located between the second layer 414B and the third layer 414C. An outer conductive layer 420 is located above the third layer 414C.

[0059] In the depicted example, a plurality of commercially available surface-mountable electronic components and / or surface-mountable metal structures 422 together form a ground shield electrically connected between the first PCB 402 and the second PCB 412. Within the ground shield, different commercially available surface-mountable electronic components 422 may have different types of connections and provide different functions. In particular, commercially available surface-mountable electronic components and / or surface-mountable metal structures 422A, 422B, 422G, and 422H are all electrically connected between the ground planes 406 and 416. For example, these components may be zero-ohm resistors. Commercially available surface-mountable electronic components and / or surface-mountable metal structures 422D are electrically connected between the power planes 408 and 418. Commercially available surface-mountable electronic components 422B, 422C, 422E, and 422F are decoupling, filtering, or matching components that are electrically connected between different conductive traces on the surfaces of the first and second PCBs 402, 412. In some implementations, additional decoupling, filtering, or matching components may reside entirely on one PCB and be connected to any one of the decoupling, filtering, or matching components 422B, 422C, 422E, 422F. These additional decoupling, filtering, or matching components may be used to provide performance gains and / or additional functionality for filtering or matching applications. For example, a multi-pole lumped element filter may be constructed. Such different electrical connections and functionality provided by different commercially available surface-mountable electronic components 422 may allow design flexibility because the PCBs may be electrically connected to each other via any suitable exposed conductors (e.g., copper) on the PCB surface.

[0060] Note that outer conductive layers 410 and 420 may optionally be added to electronic assembly 400 to provide additional EMI shielding. In such cases, through holes are added to complete the shielding case.

[0061] Figure 5 An example electronic assembly 500 is shown. The depicted view is from Figure 2A However, line BB is provided only as a reference system because electronic assembly 500 is different from Figure 2A2. The electronic assembly 200 shown in FIG. The electronic assembly 500 includes a first PCB 502 including a first ground plane 508 and a second PCB 504 including a second ground plane 510. The first PCB 502 is opposite to the second PCB 504 in the stack so that the ground planes 508 and 510 provide mutual EMI shielding. Commercially available surface-mountable electronic components and / or surface-mountable metal structures 506A and 506B are electrically connected between the ground planes 508 and 510 of the first PCB 502 and the second PCB 504, as a ground shield to cooperate with the mutually shielded PCBs 502 and 504 to form a portion of an internal shielding area 512.

[0062] Using commercially available surface-mountable electronic components and / or surface-mountable metal structures to form the ground shield can reduce the height (Z) of the inner shielding area 512 relative to an assembly in which each PCB is individually shielded via a "can" style EMI shield. Such a reduced height can reduce the overall form factor of the electronic assembly 500. However, due to the limited height of the inner shielding area 512, different electronic assemblies can be intelligently arranged on the surfaces of the two PCBs 502, 504 so that the electronic components do not contact or otherwise interfere with each other. For example, a capacitor 514 with a larger height requirement can be positioned on the first PCB 502 so that no electronic components on the second PCB 504 are opposite to the capacitor 514. As another example, a surface mount component 516 with a smaller height requirement can be positioned on the first PCB 502 and an integrated circuit 518, also with a smaller height requirement, can be positioned on the second PCB 504 to be opposite to the surface mount component 516, because the two electronic components will not contact or otherwise mechanically interfere with each other.

[0063] The internal shielding area 512 can allow the use of an unshielded electrical connector 520 to be electrically connected between the first PCB 502 and the second PCB 504. The unshielded electrical connector 520 can be electrically connected between any suitable electronic components, traces, and other connection points on the PCBs 502, 504. The unshielded electrical connector 520 does not need to have any EMI shielding material or only requires a small amount of EMI shielding material because the electrical connector 520 resides in the internal shielding area 512. The lack of EMI shielding material can reduce the cost of the electrical connector 520. In some examples, if a lower speed or more current is required, the electrical connector 520 is composed of a plurality of commercially available surface-mountable electronic components and / or surface-mountable metal structures. The electrical connector 520 can also be an integrated structure to support high speed or other requirements.

[0064] The internal shielding area 512 can allow design flexibility for the electronic assembly 500 because different electrical connections between the PCBs 502, 504 can be placed at any location within the internal shielding area 512. For example, the unshielded electrical connector 520 can be positioned at any suitable location within the internal shielding area 512. As another example, commercial surface-mountable electronic components and / or surface-mountable metal structures 522 can be connected between the ground planes 508 and 510 to provide a ground reference at any suitable location within the internal shielding area 512. In some implementations, multiple commercial surface-mountable electronic components and / or surface-mountable metal structures placed internally in a manner similar to the commercial surface-mountable electronic components or surface-mountable metal structures 522 can be used to create an internal shielding cavity that is isolated from each other. Additionally or alternatively, one or more commercial surface-mountable electronic components are electrically connected between the PCBs 502, 504 at any location to serve as an interconnect. In general, the internal shielding area 512 provides flexibility for the various electronic components to be arranged on the surface of the PCBs 502 , 504 according to any suitable layout design depending on the purpose of the electronic assembly 500 .

[0065] Figure 6 Another example electronic assembly 600 is schematically illustrated, wherein a first PCB 602 cooperates with a second PCB 604 and a third PCB 606 to provide mutual shielding, the second PCB 604 and the third PCB 606 being electrically connected on the same side / surface 608 of the first PCB 602. The first PCB 602 includes a first ground plane 610. The second PCB includes a second ground plane 612. The third PCB includes a third ground plane 614. The first PCB 602 is opposite the second PCB 604 in a stack such that the first and second ground planes 610 and 612 provide mutual EMI shielding. Commercially available surface-mountable electronic components and / or surface-mountable metal structures 616A and 616B are electrically connected between the first and second ground planes 610 and 612 of the first PCB 602 and the second PCB 604 as a ground shield that cooperates with the mutually shielded PCBs 602 and 604 to form a portion of an internal shielding area that isolates electronic components 618 (which may be, for example, integrated circuits).

[0066] Similarly, the first PCB 602 is opposite to the third PCB 606 in the stack so that the first and third ground planes 610 and 614 provide mutual EMI shielding. Commercial surface-mountable electronic components and / or surface-mountable metal structures 616C and 616D are electrically connected between the first and third ground planes 610 and 614 of the first PCB 602 and the third PCB 606, as a ground shield that cooperates with the mutually shielded PCBs 602 and 606 to form a portion of an internal shielding area that isolates the electronic component 612 (which can be a capacitor). In the depicted example, the electronic components 618 and 620 can be isolated from each other in different mutually shielded internal areas. In some examples, additional electronic components can be mounted to either the second PCB 604 or the third PCB 606 in a separate internal shielding area.

[0067] In the depicted scenario, a larger first PCB cooperates with smaller second and third PCBs attached to the first PCB to provide mutual shielding.

[0068] Figure 7 Another example electronic assembly 700 is schematically illustrated in which a first PCB 702 cooperates with a second PCB 704 and a third PCB 706 to provide mutual shielding, with the second PCB 704 and the third PCB 706 both being electrically connected on opposite sides / surfaces of the first PCB 702. In particular, the second PCB 704 is electrically connected to a first side 708 of the first PCB 702. The third PCB 706 is electrically connected to a second side 710 opposite the first side 708. The first PCB 702 includes a first ground plane 712. The second PCB includes a second ground plane 714. The third PCB includes a third ground plane 716. The first PCB 702 is opposite the second PCB 704 in the stack such that the first and second ground planes 712 and 714 provide mutual EMI shielding. Commercially available surface-mountable electronic components and / or surface-mountable metal structures 718A and 718B are electrically connected between the first and second ground planes 712 and 714 of the first PCB 702 and the second PCB 704, acting as a ground shield that cooperates with the mutually shielded PCBs 702 and 704 to form a portion of an internal shielding area that isolates the electronic component 720 (which may be, for example, an integrated circuit).

[0069] Similarly, the first PCB 702 is opposite to the third PCB 706 in the stack so that the first and third ground planes 712 and 716 provide mutual EMI shielding. Commercially available surface-mountable electronic components and / or surface-mountable metal structures 718C and 718D are electrically connected between the first and third ground planes 712 and 716 of the first PCB 702 and the third PCB 706, as a ground shield that cooperates with the mutually shielded PCBs 702 and 706 to form a portion of an internal shielding area that isolates electronic components 722 (which can be, for example, an integrated circuit). In the depicted example, the electronic components 720 and 722 can be isolated from each other in different mutually shielded internal areas. In some examples, additional electronic components can be mounted to any of the first PCB 702, the second PCB 704, or the third PCB 706 in a separate internal shielding area.

[0070] In the depicted example, multiple PCBs are stacked so that each PCB mutually shields adjacent PCBs. In some implementations, a larger PCB may have multiple smaller mutually shielding PCBs on its top and bottom surfaces.

[0071] It should be understood that the PCB can cooperate with any suitable number of additional PCBs to provide mutual shielding. In addition, multiple PCBs can have any suitable spatial arrangement relative to each other to provide such mutual shielding. In some implementations, multiple PCBs can be formed into geometric shapes so that the PCBs shield each other. For example, six PCBs can form the faces of a cube with internal shielding areas. In such cases, the edges of the PCBs will be mechanically and electrically connected. In this case, commercial surface-mountable electronic components or surface-mountable metal structures may not be suitable for providing electrical connections between PCBs because the PCBs may not be parallel to each other.

[0072] Figure 8 Aspects of an example method 800 for producing an electronic assembly as described herein are shown. At 802, method 800 includes electrically connecting and mechanically attaching one or more surface-mountable electronic components, surface-mountable metal structures, and / or other conductors to a printed circuit board (PCB) including a first plurality of electronic components. The one or more surface-mountable electronic components, surface-mountable metal structures, and / or other conductors may at least partially form a perimeter around at least one of the first plurality of electronic components on the first PCB. For example, the one or more surface-mountable electronic components, surface-mountable metal structures, and / or other conductors may be electrically connected and mechanically attached to a ground plane, a power plane, or a conductive trace of the first PCB.

[0073] In some examples, a plurality of surface-mountable electronic components, surface-mountable metal structures, or other conductors may form a perimeter around the entirety of the first plurality of electronic components on the first PCB. In some examples, a plurality of surface-mountable electronic components, surface-mountable metal structures, or other conductors may form a perimeter around a single electronic component or group of electronic components on the first PCB. In some examples, a plurality of commercially available surface-mountable electronic components, surface-mountable metal structures, or other conductors may form a perimeter around the first PCB and form an additional internal shielding region around one or more electronic components of the first PCB.

[0074] In some examples, a ground shield may be formed using only a plurality of surface-mountable electronic components electrically connected and mechanically attached to a first PCB. In some examples, a plurality of surface-mountable electronic components, surface-mountable metal structures, and other conductors (e.g., stamped or drawn metals, conductive foams, metallized plastics or resins) may cooperate to form a ground shield by electrically connecting and mechanically attaching to a first PCB.

[0075] In some implementations, method 800 may optionally include placing high temperature solder (or other connecting materials, such as conductive epoxy) on the first PCB, vertically placing one or more commercial surface-mountable electronic components using a pick-and-place machine so that one end contacts the high temperature solder (or other connecting material), and reflowing the first PCB and the one or more commercial surface-mountable electronic components and / or surface-mountable metal structures in an oven to electrically connect and mechanically attach the one or more commercial surface-mountable electronic components and / or surface-mountable metal structures to the first PCB. In some implementations, the one or more commercial surface-mountable electronic components and / or surface-mountable metal structures may be electrically connected and mechanically attached to the first PCB via at least one of mechanical crimping, spring force, conductive epoxy, or welding.

[0076] At 804, method 800 includes aligning the first PCB with a second PCB including a second plurality of electronic components such that one or more surface mountable electronic components form a perimeter on the second PCB at least partially around at least one of the second plurality of electronic components. In some implementations, this method step can optionally be performed by a pick and place machine.

[0077] At 806, method 800 includes electrically connecting and mechanically attaching one or more surface-mountable electronic components, surface-mountable metal structures, or other conductors to the second PCB when the first PCB and the second PCB are aligned, so that the first PCB is electrically connected to the second PCB via the one or more surface-mountable electronic components, surface-mountable metal structures, or other conductors to encapsulate and electromagnetically isolate at least one of the first plurality of electronic components and at least one of the second plurality of electronic components. For example, the one or more surface-mountable electronic components, surface-mountable metal structures, or other conductors may be electrically connected and mechanically attached to a ground plane, a power plane, or a conductive trace of the second PCB.

[0078] In some implementations, one or more commercial surface-mountable electronic components and / or surface-mountable metal structures may first be soldered to a first PCB via a high temperature solder. Then, one or more commercial surface-mountable electronic components and / or surface-mountable metal structures may be soldered to a second PCB via a reflow solder having a lower melting point than the high temperature solder. This may allow the entire first PCB and the connected commercial surface-mountable electronic components and / or surface-mountable metal structures to be reflowed in an oven to be soldered to the second PCB without the high temperature solder melting.

[0079] In some implementations, multiple additional smaller PCBs can be added to either side of the first larger PCB following the same process. In some implementations, three or more PCBs can be stacked using the same process.

[0080] The resulting electronic assembly enables the PCB to cooperate with one or more surface-mountable electronic components, surface-mountable metal structures, or other conductors to provide mutual EMI shielding to encapsulate and electromagnetically isolate at least one of the first plurality of electronic components on the first PCB and at least one of the second plurality of electronic components on the second PCB. In some examples, more than two PCBs are used to form a more complex mutually shielded assembly.

[0081] In one example, an electronic assembly includes: a first printed circuit board (PCB), the first PCB including a first plurality of electronic components and a first conductive layer; a second PCB, the second PCB including a second plurality of electronic components and a second conductive layer; and a ground shield, the ground shield electrically connected between the first conductive layer of the first PCB and the second conductive layer of the second PCB to electrically connect the first PCB and the second PCB, wherein the ground shield at least partially shields at least one of the first plurality of electronic components and / or at least one of the second plurality of electronic components, wherein the ground shield includes at least one surface-mountable electronic component electrically connected between the first conductive layer of the first PCB and the second conductive layer of the second PCB, and wherein the first PCB and the second PCB are arranged in a stacked manner so that the first conductive layer and the second conductive layer mutually shield at least one of the first plurality of electronic components and at least one of the second plurality of electronic components from electromagnetic interference. In this example and / or other examples, the at least one surface-mountable electronic component may include a zero-ohm resistor. In this example and / or other examples, the at least one surface-mountable electronic component may include a decoupling, filtering, or matching component. In this example and / or other examples, the decoupling, filtering, or matching component may be one of a shunt capacitor, an inductor, or a multi-element filter. In this example and / or other examples, the at least one surface-mountable electronic component may include a non-rigid or flexible surface-mountable electronic component. In this example and / or other examples, at least one of the first plurality of electronic components and / or at least one of the second plurality of electronic components may be thermally connected to the relative PCB through mechanical contact or thermal interface material. In this example and / or other examples, the electronic assembly may further include a third PCB, the third PCB includes a third conductive layer, and at least one additional surface-mountable electronic component may be electrically connected between the first conductive layer of the first PCB and the third conductive layer of the third PCB, so that the first conductive layer and the third conductive layer provide mutual shielding. In this example and / or other examples, the ground shield may include a metal sidewall or fence having at least one groove, at least one surface-mountable electronic component is positioned in the at least one groove, and the surface-mountable electronic component may be electrically connected between the first PCB and the second PCB. In this example and / or other examples, the ground shield may extend substantially along the entire first perimeter of the first PCB and the entire second perimeter of the second PCB. In this example and / or other examples, the electronic assembly may further include one or more additional surface-mountable electronic components electrically connected between the first PCB and the second PCB at any location within the mutually shielded area formed between the first PCB and the second PCB, and the one or more additional surface-mountable electronic components may serve as interconnects between the first PCB and the second PCB.In this example and / or other examples, the electronic assembly may further include an unshielded electrical connector electrically connected between the first electronic component of the first PCB and the second electronic component of the second PCB. In this example and / or other examples, the ground shield may be electrically connected to the first PCB via a high temperature solder, and the ground shield may be electrically connected to the second PCB via a reflow solder, the reflow solder having a lower melting point than the high temperature solder.

[0082] In one example, a method for manufacturing an electronic assembly includes: electrically connecting and mechanically attaching one or more surface-mountable electronic components to a printed circuit board (PCB) including a first plurality of electronic components such that the one or more surface-mountable electronic components form a perimeter on the first PCB at least partially around at least one of the first plurality of electronic components;

[0083] Aligning the first PCB with a second PCB including a second plurality of electronic components so that one or more surface-mountable electronic components form a perimeter on the second PCB at least partially around at least one of the second plurality of electronic components; and electrically connecting and mechanically attaching the one or more surface-mountable electronic components to the second PCB when the first PCB and the second PCB are aligned so that the first PCB is electrically connected to the second PCB via the one or more surface-mountable electronic components to encapsulate and electromagnetically isolate at least one of the first plurality of electronic components and at least one of the second plurality of electronic components. In this example and / or other examples, the one or more surface-mountable electronic components may be electrically connected and mechanically attached to the first PCB using a pick-and-place machine. In this example and / or other examples, the one or more surface-mountable electronic components may be electrically connected and mechanically attached to the first PCB via high temperature solder. In this example and / or other examples, the one or more surface-mountable electronic components may be electrically connected and mechanically attached to the second PCB via reflow solder, the reflow solder having a melting point lower than the high temperature solder. In this example and / or other examples, the one or more surface mountable electronic components can be electrically connected and mechanically attached to the first PCB and the second PCB via a conductive epoxy. In this example and / or other examples, the one or more surface mountable electronic components can be electrically connected and mechanically attached to the first PCB and the second PCB via one of mechanical crimping, spring force, or welding.

[0084] In one example, an electronic assembly includes: a first printed circuit board (PCB), the first PCB including a first plurality of electronic components and a first conductive layer; a second PCB, the second PCB including a second plurality of electronic components and a second conductive layer; and a ground shield, the ground shield electrically connected between the first conductive layer of the first PCB and the second conductive layer of the second PCB to electrically connect the first PCB and the second PCB, wherein the ground shield is electrically connected to the first PCB via a high temperature solder, wherein the ground shield is electrically connected to the second PCB via a reflow solder, the reflow solder having a melting point lower than the high temperature solder; and wherein the first PCB and the second PCB are arranged in a stacked manner so that the first conductive layer and the second conductive layer mutually shield at least one of the first plurality of electronic components and at least one of the second plurality of electronic components from electromagnetic interference. In this example and / or other examples, the ground shield may include a plurality of surface mountable electronic components electrically connected between the first conductive layer of the first PCB and the second conductive layer of the second PCB, and the plurality of surface mountable electronic components may be positioned substantially around the entirety of the first perimeter of the first PCB and the second perimeter of the second PCB to electrically connect the first PCB and the second PCB.

[0085] It should be understood that the configurations and / or methods described herein are exemplary in nature, and these specific embodiments or examples should not be considered to have limiting significance, as many variations are possible. The specific routines or methods described herein may represent one or more of any number of processing strategies. Thus, the various actions illustrated and / or described may be performed in the illustrated and / or described order, in other orders, in parallel, or omitted. Likewise, the order of the processes described above may be changed.

[0086] The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various processes, systems and configurations, and other features, functions, acts, and / or properties disclosed herein, as well as any and all equivalents thereof.

Claims

1. An electronic assembly, comprising: a first printed circuit board PCB, the first PCB comprising a first plurality of electronic components mounted on a first surface and a first conductive layer; a second PCB including a second plurality of electronic components mounted on the second surface and a second conductive layer; as well as a ground shield electrically connected between the first conductive layer of the first PCB and the second conductive layer of the second PCB to electrically connect the first PCB with the second PCB, wherein the ground shield at least partially shields at least one of the first plurality of electronic components and / or at least one of the second plurality of electronic components, wherein the ground shield includes at least one surface-mountable electronic component, each surface-mountable electronic component physically extending between the first surface of the first PCB and the second surface of the second PCB and electrically connected between the first conductive layer of the first PCB and the second conductive layer of the second PCB, and The first PCB and the second PCB are arranged in a stacked manner so that the first surface of the first PCB is opposite to the second surface of the second PCB and so that the first conductive layer, the second conductive layer and the at least one surface-mountable electronic component jointly shield at least one of the first plurality of electronic components and at least one of the second plurality of electronic components to prevent electromagnetic interference.

2. The electronic assembly according to claim 1, wherein: The at least one surface mountable electronic component includes a zero ohm resistor.

3. The electronic assembly according to claim 1, wherein: The at least one surface-mountable electronic component comprises a decoupling, filtering or matching component.

4. The electronic assembly according to claim 3, wherein: The decoupling, filtering or matching component is one of a shunt capacitor, an inductor or a multi-element filter.

5. The electronic assembly according to claim 1, wherein: The at least one surface-mountable electronic component comprises a non-rigid surface-mountable electronic component.

6. The electronic assembly according to claim 1, wherein: At least one of the first plurality of electronic components and / or at least one of the second plurality of electronic components are thermally connected to an opposing PCB via mechanical contact or a thermal interface material.

7. The electronic assembly according to claim 1, wherein: Further comprising a third PCB comprising a third conductive layer, wherein at least one additional surface-mountable electronic component is electrically connected between the first conductive layer of the first PCB and the third conductive layer of the third PCB, such that the first conductive layer and the third conductive layer provide mutual shielding.

8. The electronic assembly according to claim 1, wherein: The ground shield includes a metal sidewall or fence having at least one slot, wherein at least one surface-mountable electronic component is positioned in the at least one slot, and wherein the surface-mountable electronic component is electrically connected between the first PCB and the second PCB.

9. The electronic assembly according to claim 1, wherein: The ground shield extends along an entire first perimeter of the first PCB and an entire second perimeter of the second PCB.

10. The electronic assembly according to claim 1, wherein: Further comprising one or more additional surface-mountable electronic components electrically connected between the first PCB and the second PCB at any location within a mutually shielded area formed between the first PCB and the second PCB, wherein the one or more additional surface-mountable electronic components serve as interconnects between the first PCB and the second PCB.

11. The electronic assembly according to claim 1, wherein: Further including: An unshielded electrical connector is electrically connected between a first electronic component of the first PCB and a second electronic component of the second PCB.

12. The electronic assembly according to claim 1, wherein: The ground shield is electrically connected to the first PCB via a high temperature solder, and the ground shield is electrically connected to the second PCB via a reflow solder having a lower melting point than the high temperature solder.

13. A method for manufacturing an electronic assembly, the method comprising: electrically connecting and mechanically attaching one or more surface-mountable electronic components to a first surface of a first printed circuit board PCB comprising a first plurality of electronic components such that the one or more surface-mountable electronic components form a perimeter on the first PCB at least partially around at least one of the first plurality of electronic components, wherein the first plurality of electronic components are mounted on the first surface of the first PCB; aligning the first PCB with a second PCB including a second plurality of electronic components such that the one or more surface-mountable electronic components form a perimeter on the second PCB at least partially around at least one of the second plurality of electronic components, wherein the second plurality of electronic components are mounted on a second surface of the second PCB; as well as When the first PCB and the second PCB are aligned so that the first surface is opposite to the second surface, the one or more surface-mountable electronic components are electrically connected and mechanically attached to the second surface of the second PCB so that each surface-mountable electronic component physically extends between the first surface of the first PCB and the second surface of the second PCB and so that the first PCB is electrically connected to the second PCB via the one or more surface-mountable electronic components to encapsulate and electromagnetically isolate at least one of the first plurality of electronic components and at least one of the second plurality of electronic components.

14. The method according to claim 13, characterized in that The one or more surface mountable electronic components are electrically connected and mechanically attached to the first PCB using a pick and place machine.

15. The method according to claim 13, characterized in that The one or more surface mountable electronic components are electrically connected and mechanically attached to the first PCB via high temperature solder.

16. The method of claim 15, characterized in that The one or more surface mountable electronic components are electrically connected and mechanically attached to the second PCB via a reflow solder having a lower melting point than the high temperature solder.

17. The method according to claim 13, characterized in that The one or more surface mountable electronic components are electrically connected and mechanically attached to the first PCB and the second PCB via a conductive epoxy.

18. The method according to claim 13, characterized in that The one or more surface mountable electronic components are electrically connected and mechanically attached to the first PCB and the second PCB via one of mechanical crimping, spring force, or soldering.

19. An electronic assembly comprising: a first printed circuit board PCB, the first PCB comprising a first plurality of electronic components mounted on a first surface and a first conductive layer; a second PCB including a second plurality of electronic components mounted on the second surface and a second conductive layer; as well as a ground shield electrically connected between the first conductive layer of the first PCB and the second conductive layer of the second PCB to electrically connect the first PCB with the second PCB, wherein the ground shield is electrically connected to the first PCB via a high temperature solder, wherein the ground shield is electrically connected to the second PCB via a reflow solder having a lower melting point than the high temperature solder, wherein the ground shield includes a plurality of surface mountable electronic components, each surface mountable electronic component physically extending between the first surface of the first PCB and the second surface of the second PCB and electrically connected between the first conductive layer of the first PCB and the second conductive layer of the second PCB; as well as The first PCB and the second PCB are arranged in a stacked manner so that the first surface of the first PCB is opposite to the second surface of the second PCB and so that the first conductive layer, the second conductive layer and the plurality of surface-mountable electronic components jointly shield at least one of the first plurality of electronic components and at least one of the second plurality of electronic components to prevent electromagnetic interference.

20. The electronic assembly according to claim 19, wherein: The plurality of surface mountable electronic components are positioned around an entirety of a first perimeter of the first PCB and a second perimeter of the second PCB to electrically connect the first PCB to the second PCB.

Images