PATENT DOCUMENT

Publication Number: US-9743564-B2
Application Number: US-201514830351-A
Country: US
Kind Code: B2

Title: Electromagnetic shielding structures

Abstract:
An electronic device may have a printed circuit to which electrical components are mounted. Electromagnetic shields may be mounted to the printed circuit over the components to suppress interference. A shield may have a metal frame covered with a conductive fabric. The conductive fabric may cover an opening in the top of the frame. An insulating layer may be formed on the lower surface of the conductive fabric to prevent shorts between components on the printed circuit and the conductive fabric. An insulating cap such as an elastomeric polymer cap may also be formed over each component to provide electrical isolation between the components and the conductive fabric. Shields may be formed by coupling shield cans to subscriber identity module shields or other metal structures in a device. Intervening wall structures may be removed to help provide additional shielding volume.

Claims:
What is claimed is: 
     
       1. A shield for electromagnetically shielding components on a printed circuit, comprising:
 a metal frame having an opening; 
 a conductive fabric that covers the opening; and 
 an insulating layer on a surface of the conductive fabric, wherein the insulating layer is interposed between the components on the printed circuit and the conductive fabric. 
 
     
     
       2. The shield defined in  claim 1  wherein the metal frame comprises four sidewalls and wherein the opening comprises a rectangular opening. 
     
     
       3. The shield defined in  claim 2  further comprising conductive adhesive that attaches the conductive fabric to the metal frame. 
     
     
       4. The shield defined in  claim 3  wherein the metal frame has planar upper metal wall portion that extends horizontally inwards from the four sidewalls and that surrounds the opening. 
     
     
       5. The shield defined in  claim 4  wherein the conductive adhesive is attached between the planar upper metal wall portion and the conductive fabric. 
     
     
       6. The shield defined in  claim 5  wherein the conductive fabric comprises intertwined fibers, metal particles, and a polymer binder in which the intertwined fibers and metal particles are embedded. 
     
     
       7. The shield defined in  claim 5  wherein the planar upper metal wall portion has an inner surface of a first height and wherein the conductive fabric has an inner surface of a second height that is greater than the first height. 
     
     
       8. The shield defined in  claim 1  wherein the insulating layer comprises a polymer layer and a layer of adhesive that attaches the polymer layer to the surface of the conductive fabric. 
     
     
       9. A shield for electromagnetically shielding components on a printed circuit, comprising:
 a shield can; and 
 a subscriber identity module shield, wherein adjacent portions of the shield can and the subscriber identity module shield are joined together. 
 
     
     
       10. The shield defined in  claim 9  wherein the shield can and subscriber identity module have at least one horizontal wall protrusion that mates with horizontally extending tabs. 
     
     
       11. The shield defined in  claim 10  wherein the horizontally extending tabs comprise upper tabs and lower tabs and wherein the horizontal wall protrusion is received between the upper and lower tabs. 
     
     
       12. The shield defined in  claim 10  wherein the horizontal wall protrusion protrudes outward from a horizontally extending planar upper wall of the shield can. 
     
     
       13. The shield defined in  claim 10  wherein the horizontal wall protrusion protrudes outward from a horizontally extending planar upper wall of the subscriber identity module shield. 
     
     
       14. The shield defined in  claim 9  further comprising a planar metal wall portion that is attached between the shielding can and the subscriber identity module shield. 
     
     
       15. The shield defined in  claim 14  further comprising welds that attach the planar metal wall portion to the shielding can and to the subscriber identity module shield. 
     
     
       16. The shield defined in  claim 9  further comprising conductive fabric that is attached between the shielding can and the subscriber identity module shield. 
     
     
       17. Apparatus, comprising:
 a printed circuit; 
 electrical components soldered to the printed circuit; 
 a first shield that electromagnetically shields the electrical components, wherein the first shield includes a first vertical metal wall that is soldered to the printed circuit and a first surface extending horizontally from the first vertical metal wall; and 
 a second shield that electromagnetically shields an additional electronic component, wherein the second shield includes a second vertical metal wall and a second surface extending horizontally from the second vertical metal wall, and the second surface has tabs configured to attach the second surface to the first surface. 
 
     
     
       18. The apparatus defined in  claim 17  wherein the tabs comprise upper and lower tabs, and the first surface is interposed between the upper and lower tabs when the second surface is attached to the first surface.

Description:
This application claims the benefit of provisional patent application No. 62/043,055 filed on Aug. 28, 2014, which is hereby incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     This relates generally to electronic devices, and, more particularly, to electronic devices that include electrical components. 
     Electronic devices include electronic components such as integrated circuits and other circuitry. Electronic components may be mounted on printed circuit boards. Metal shielding cans are often used to block electromagnetic interference. In a typical scenario, a metal shielding can is soldered to a printed circuit board so that the metal shielding can overlaps one or more electrical components on the printed circuit board. The components that are shielded in this way are protected from interference from other components in an electronic device. The presence of a shield may also help block electromagnetic interference signals that might otherwise be emitted by the components under the shield. 
     Conventional shielding cans are often bulky. This can make it difficult or impossible to mount electrical components in a compact electronic device where space is at a premium. At the same time, it may be difficult or impossible to omit shielding to save space, because omission of the shielding could lead to interference that would make device performance unreliable. 
     It would therefore be desirable to be able to provide compact electromagnetic shielding arrangements for use in an electronic devices. 
     SUMMARY 
     An electronic device may have a printed circuit to which electrical components are mounted. Electromagnetic shields may be mounted to the printed circuit over the components to suppress interference. A shield may have a metal frame covered with a conductive fabric. The conductive fabric may cover an opening in the top of the frame. An insulating layer may be formed on the lower surface of the conductive fabric to prevent shorts between components on the printed circuit and the conductive fabric. An insulating cap such as an elastomeric polymer cap may also be formed over each component to provide electrical isolation between the components and the conductive fabric. 
     Shields may be formed by coupling shield cans to subscriber identity module shields or other metal structures in a device. Intervening wall structures may be removed to help provide additional shielding volume. A subscriber identity module shield and a shield can may be coupled by inserting a horizontally extending planar wall portion into bent tabs formed from bent sidewalls. A subscriber identity module shield and a shield can may also be coupled together using a welded sheet metal member, conductive fabric, or other conductive material. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram of an illustrative electronic device in accordance with an embodiment. 
         FIG. 2  is a cross-sectional side view of an illustrative electronic device in accordance with an embodiment. 
         FIG. 3  is a side view of an illustrative printed circuit on which electrical components and shielding structures have been mounted in accordance with an embodiment of the present invention. 
         FIG. 4  is a top view of an illustrative rectangular shield covering electrical components on a printed circuit in accordance with an embodiment. 
         FIG. 5  is a top view of an illustrative L-shaped shield covering electrical components in accordance with an embodiment. 
         FIG. 6  is a cross-sectional side view of an illustrative shield having a conductive fabric cover in accordance with an embodiment. 
         FIG. 7  is a cross-sectional side view of a portion of a shielding structure having a conductive fabric cover showing how an insulating layer such as a sheet of adhesive-backed polymer and an optional polymeric component cover may provide insulation and separation between an electrical component and the interior surface of the conductive fabric cover in accordance with an embodiment. 
         FIG. 8  is a perspective view of an illustrative metal structure such as a subscriber identity module (SIM) card shield that may receive a SIM card or other mating component in accordance with an embodiment. 
         FIG. 9  is a perspective view of the illustrative SIM card shield of  FIG. 9  showing how portions of the wall of the receptacle may be configured to form laterally protruding tabs in accordance with an embodiment. 
         FIG. 10  is an exploded perspective view of an illustrative SIM card receptacle having laterally protruding tabs that mate with a laterally extending portion of a shield can or other shield structure to form a shield in accordance with an embodiment. 
         FIG. 11  is a cross-sectional side view of the mating shield can and SIM card receptacle of  FIG. 10  in accordance with an embodiment. 
         FIG. 12  is a cross-sectional side view of an illustrative shield can structure having a protruding portion with an upper surface that contacts a tab from a metal structure such as a SIM card receptacle in accordance with an embodiment. 
         FIG. 13  is a cross-sectional side view of an illustrative shield can structure having a protruding portion with a lower surface that contacts a tab from a metal structure such as a SIM card receptacle in accordance with an embodiment. 
         FIG. 14  shows how a welded metal sheet may be used to join a metal structure such as a SIM card receptacle with a laterally extending shield can wall to form an electromagnetic shield in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     An illustrative electronic device is shown in  FIG. 1 . Electronic device  10  may be a computing device such as a laptop computer, a computer monitor containing an embedded computer, a tablet computer, a cellular telephone, a media player, or other handheld or portable electronic device, a smaller device such as a wrist-watch device, a pendant device, a headphone or earpiece device, a device embedded in eyeglasses or other equipment worn on a user&#39;s head, or other wearable or miniature device, a television, a computer display that does not contain an embedded computer, a gaming device, a navigation device, an embedded system such as a system in which electronic equipment with a display is mounted in a kiosk or automobile, equipment that implements the functionality of two or more of these devices, or other electronic equipment. 
     As shown in  FIG. 1 , electronic device  10  may have control circuitry  16 . Control circuitry  16  may include storage and processing circuitry for supporting the operation of device  10 . The storage and processing circuitry may include storage such as hard disk drive storage, nonvolatile memory (e.g., flash memory or other electrically-programmable-read-only memory configured to form a solid state drive), volatile memory (e.g., static or dynamic random-access-memory), etc. Processing circuitry in control circuitry  16  may be used to control the operation of device  10 . The processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors and other wireless communications circuits, power management units, audio chips, application specific integrated circuits, etc. 
     Input-output circuitry in device  10  such as input-output devices  18  may be used to allow data to be supplied to device  10  and to allow data to be provided from device  10  to external devices. Input-output devices  18  may include buttons, joysticks, scrolling wheels, touch pads, key pads, keyboards, microphones, speakers, tone generators, vibrators, cameras, sensors such as touch sensors, proximity sensors, ambient light sensors, compasses, gyroscopes, accelerometers, light-emitting diodes and other status indicators, data ports, etc. A user can control the operation of device  10  by supplying commands through input-output devices  18  and may receive status information and other output from device  10  using the output resources of input-output devices  18 . 
     Input-output devices  18  may include one or more displays. Device  10  may, for example, include a touch screen display that includes a touch sensor for gathering touch input from a user or a display that is insensitive to touch. A touch sensor for a display in device  10  may be based on an array of capacitive touch sensor electrodes, acoustic touch sensor structures, resistive touch components, force-based touch sensor structures, a light-based touch sensor, or other suitable touch sensor arrangements. 
     Power for device  10  may be provided by an external source of power and/or an internal battery. The components for device  10  such as circuitry  16  and devices  18  and other structures in device  10  may be implemented using integrated circuits, discrete components (e.g., resistors, capacitors, inductors), microelectromechanical systems (MEMS) devices, portions of housing structures, packaged parts, and other devices and structures. 
     Control circuitry  16  may be used to run software on device  10  such as operating system code and applications. During operation of device  10 , the software running on control circuitry  16  may display images for a user on one or more displays and may use other internal components such as input-output devices  18 . Device  10  may use communications circuits to send and receive wireless and wired data. For example, device  10  may use light-emitting components to transmit data and may use light-receiving components to receive transmitted light signals. Device  10  may also use light-emitting components, light-receiving components, audio components, capacitive sensors, microelectromechanical systems devices, and other components as sensors and output devices. Device  10  may use wireless circuits in circuitry  16  (e.g., a baseband processor and associated radio-frequency transceiver circuitry) to transmit and receive wireless signals. For example, device  10  may transmit and receive cellular telephone signals and/or wireless local area network signals or other wireless data. 
     A cross-sectional side view of an illustrative electronic device is shown in  FIG. 2 . As shown in  FIG. 2 , device  10  may have a housing such as housing  12 . Housing  12 , which may sometimes be referred to as an enclosure or case, may be formed of plastic, glass, ceramics, fiber composites, metal (e.g., stainless steel, aluminum, etc.), other suitable materials, or a combination of any two or more of these materials. Housing  12  may be formed using a unibody configuration in which some or all of housing  12  is machined or molded as a single structure or may be formed using multiple structures (e.g., an internal frame structure, one or more structures that form exterior housing surfaces, etc.). Device  10  may have inner housing structures that provide additional structural support to device  10  and/or that serve as mounting platforms for printed circuits and other structures. Structural internal housing members may sometimes be referred to as housing structures and may be considered to form part of housing  12 . 
     Device  10  may have a display such as display  14 . Display  14  may be a touch screen display that incorporates a layer of conductive capacitive touch sensor electrodes or other touch sensor components (e.g., resistive touch sensor components, acoustic touch sensor components, force-based touch sensor components, light-based touch sensor components, etc.) or may be a display that is not touch-sensitive. Capacitive touch screen electrodes may be formed from an array of indium tin oxide pads or other transparent conductive structures. 
     Display  14  of device  10  may be formed from a display module such as display module  22  mounted under a cover layer such as display cover layer  20  (as an example). Display  14  (display module  22 ) may be a liquid crystal display, an organic light-emitting diode display, a plasma display, an electrophoretic display, a display that is insensitive to touch, a touch sensitive display that incorporates and array of capacitive touch sensor electrodes or other touch sensor structures, or may be any other type of suitable display. Display cover layer  20  may be planar or curved and may be formed from clear glass, a transparent plastic member, a transparent crystalline member such as a sapphire layer, clear ceramics, other transparent materials, or combinations of these structures. 
     Electrical components  26  may be mounted within the interior of housing  12 . Components  26  may be mounted to printed circuits such as printed circuit  24 . Printed circuit  24  may be a rigid printed circuit board (e.g., a printed circuit board formed from fiberglass-filled epoxy or other rigid printed circuit board material) or may be a flexible printed circuit (e.g., a printed circuit formed from a sheet of polyimide or other flexible polymer layer). Patterned metal traces within printed circuit board  24  may be used to form signal paths between components  26 . If desired, components such as connectors may be mounted to printed circuit  24 . As shown in  FIG. 2 , for example, a cable such as flexible printed circuit cable  28  may couple display module  22  to connector  30 . Connector  30  may couple cable  28  to traces within printed circuit  24 . When coupled as shown in  FIG. 2 , signals associated with operation of display  14  may pass to display module  22  from signal lines in printed circuit  24  through cable  28  and connector  30 . 
     Components  26  may be mounted to signal lines in printed circuit  24  using solder or other conductive materials. As shown in  FIG. 3 , metal traces  32  in printed circuit  24  may be used to interconnect components  26 . Metal traces  32  may be formed in one or more metal layers on printed circuit  24  (i.e., printed circuit  24  may be a single layer printed circuit or a multilayer printed circuit). In multilayer printed circuit configurations, metal vias may be used to interconnect metal signal traces on different layers. The patterned metal traces on printed circuit  24  may be used to route signals such as digital signals, analog signals, power signals, ground signals, etc. For example, ground signals may be coupled to conductive structures such as conductive shield structures  34 . Each conductive shield structure  34  may be used to electromagnetically shield one or more components  26 . The components that are shielded in this way may have one or more different heights (i.e., different vertical dimensions above the surface of printed circuit  24 ). 
     Conductive shields  34  may be formed from conductive material. The walls of shields  34  define cavity shapes that are configured to receive components  26  (i.e., shapes that allow shields  34  to be mounted to printed circuit  24  overlapping components  26 ). The conductive material for conductive shields  34  may be formed into a desired shape using techniques such as stamping, machining, casting, laser cutting, welding, attachment of conductive structures using conductive adhesive or solder, etc. Shields  34  may have a horizontal planar cover and four downwardly extending sidewalls that form an open box shape or may have other shapes and may sometimes be referred to as shield cans. 
     The footprint of each shield  34  may be rectangular in shape or may have other suitable shapes. As shown by the top view of illustrative shield  34  of  FIG. 4 , shield  34  may have a rectangular outline (when viewed from above) and may overlap multiple components. A top view of an illustrative configuration for shield  34  that has a non-rectangular L-shape is shown in  FIG. 5 . Other non-rectangular shapes for the outlines of shields  34  may be used if desired (e.g., U-shapes, shapes with curved edges, shapes with combinations of curved and straight edges, non-rectangular shapes with fewer than four sides or more than four sides, etc.). The footprints of shields  34  that are shown in  FIGS. 4 and 5  are merely illustrative. 
     Shields  34  may be formed entirely or primarily of metal or may be formed from a combination of conductive materials (e.g., conductive metal, conductive polymers, conductive intertwined fibers such as conductive fabric, conductive materials that include fibers embedded within a polymer matrix such as carbon-fiber composites and other fiber composite materials, and/or other conductive materials). 
     In some applications, it may be desirable to minimize the vertical dimensions of some or all of shield  34  (e.g., to minimize shield volume). The height of shield  34  can be minimized by forming an opening in the upper surface of shield  34  and covering the opening with a thin conductive layer. This forms a shield structure with a raised center that may efficiently accommodate a collection of shorter and taller components. 
     The sidewalls of shield  34  may, as an example, be formed from metal. An opening may be formed in the upper wall of a metal frame structure used in forming shield  34 . In a configuration of the type shown in  FIG. 4 , for example, a rectangular opening may be formed in the upper wall of a rectangular metal can, creating a metal frame formed from four metal vertical sidewalls and an upper wall with a rectangular opening. This rectangular opening may then be covered with a thin conductive material (e.g., a layer of material having a thickness that is less than the sidewall thickness and/or that is less than the wall thickness of the other portions of the metal can or that has any other suitable thickness). 
     The presence of the thin layer over the opening ensures that components  26  are enclosed within conductive material, thereby ensuring that shield  34  can provide components  26  with satisfactory electromagnetic shielding. The thinness of the thin layer and the variations in interior heights for components  26  within the shield may help reduce the overall size of shield  34 . 
     In general, any suitable conductive material may be used to form the thin covering layer that seals the opening in the upper surface of the metal can (e.g., polymer covered with a metal coating, a thin sheet metal layer, etc.). With one suitable arrangement, which is sometimes described herein as an example, the thin covering layer is formed from a conductive fabric. Fabrics may be formed from woven fibers that form a mesh or other fiber pattern, from fibers that are intertwined using a random pattern, or from other intertwined fiber arrangements. The fabric may be rendered conductive by forming some or all of the fibers in the fabric from metal fibers, by forming some or all of the fibers in the fabric from polymer fibers coated with metal, by incorporating metal particles into a binder material that is used as a matrix to hold the fibers together and/or that is used as a coating on one or more surfaces of the fibers, by coating one or more surfaces of a set of intertwined fibers or interstitial spaces within these fibers with metallic paint or metal (e.g., metal deposited using physical vapor deposition to form a coating layer, etc.), by forming the fibers of the fabric from carbon materials (e.g., carbon nanotubes, other carbon fibers, or other non-metal conductive fibers), by incorporating carbon particles or other conductive particles into the fabric and/or a polymer binder that coats and/or binds the intertwined fibers, or using other suitable techniques for forming conductive fabric. 
     A cross-sectional side view of an illustrative shield with a conductive fabric covering layer such as shield  34  of  FIG. 4  taken along line  36  and viewed in direction  38  is shown in  FIG. 6 . As shown in  FIG. 6 , shield  34  may have covering layer  34 - 3 . Covering layer  34 - 3  may include conductive fabric layer  46 . Insulating layer  44  may be formed on the inner surface of covering layer  34 - 3  (e.g., on the inner surface of fabric  46 ) to help prevent components  26  from shorting to conductive fabric  46 . 
     Shield  34  may have metal portions such as metal sidewalls  34 - 1 . Shield  34  may also have upper wall portions such as metal wall portions  34 - 2  around the perimeter of shield  34 . Wall portions  34 - 2  may lie in the horizontal X-Y plane and may run perpendicular to walls  34 - 1 . Opening  48  may be formed in the upper surface of the metal portion of shield  34  (i.e., within upper wall  34 - 2 ). Together, wall portions  34 - 1  and  34 - 2  form a metal frame to which fabric  46  may be attached using conductive adhesive  42 . If desired, metal wall portions  34 - 2  can be omitted from the metal frame and fabric  46  can be attached directly to sidewalls  34 - 1 . The configuration of  FIG. 6  in which fabric  46  covers opening  48  by attachment to the portions of upper wall  34 - 2  that run around the rectangular periphery of opening  48  is merely illustrative. 
     The metal frame of shield  34  may be attached to metal traces on printed circuit  24  such as metal traces  32  using solder  40 . Solder  40  may also be used in mounting components  26  to metal traces  32 . The metal traces that are connected to the metal frame of shield  34  may be ground traces that ground metal shield  34 . 
     The metal walls of the frame of shield  34  such as metal sidewalls  34 - 1  and upper metal wall  34 - 2  may have a thickness that is smaller than the thickness of fabric  46 . The thickness of the metal frame may be, for example, about 150 microns, 100-200 microns, more than 100 microns, less than 200 microns, or other suitable thickness and the thickness of fabric  46  may be, for example, about 75 microns, 50-125 microns, more than 50 microns, less than 125 microns, or other suitable thickness. 
     Because fabric  46  is mounted to the outer surface of wall  34 - 2 , the inner surface of fabric  46  may lie above the inner surface of wall  34 - 2 . This allows taller components such as components of height HB to be mounted in the center of shield  34  where these components are overlapped by fabric  46 , whereas shorter components such as components of height HS (less than HB) may be mounted under shorter portions of shield  34  such as the portions of shield  34  under upper wall  34 - 2 . The thinness of fabric  46  helps minimize any increases in shield height in the center of shield  34  covering opening  48  that might result from the presence of fabric  46 . As shown in  FIG. 6 , this type of configuration allows components of different heights to be efficiently shielded under shield  34  and avoids the need to increase the height of shield  34  in peripheral areas such as wall portions  34 - 2 . As a result, wall portions  34 - 2  may be shorter (and therefore more efficiently mounted within device  10 ) than would be possible if all of shield  34  were to be constructed with a metal upper wall sufficient in height to accommodate tall components of height HB. 
       FIG. 7  is a cross-sectional side view of a central portion of shield  34  that includes conductive fabric  46 . In the example of  FIG. 7 , conductive fabric  46  includes conductive particles  46 - 3  (e.g., metal particles, or other conductive particles) and intertwined fibers  46 - 2 . Fibers  46 - 2  and the conductive material of particles  46 - 3  may be embedded within polymer binder  46 - 1 . Metal particles  46 - 3  may be formed from metals such as silver, copper, nickel, or other metals. The metal of the frame of shield  34  to which fabric  46  is shorted may be formed from a nickel copper alloy or other metal. Insulating layer  44  may be formed from adhesive layer  44 - 1  and polymer layer  44 - 2 . Adhesive layer  44 - 1  may be used to attach an insulating sheet of material such as layer  44 - 2  to the inner surface of fabric  46 . 
     An optional insulating cap such as cap  50  may be formed on top of one or more of the components under shield  34 . Cap  50  may be formed from a layer of insulating material such as silicone or other polymer that is able to withstand heat generated by component  26  during operation (e.g., an elastomeric polymer, etc.). The edges of cap  50  may cover the upper portions of the sides of components  26  or cap  50  may be formed from a layer of insulating material that does not significantly extend down the sides of components  26 . 
     In addition to or as an alternative to forming shield  34  from conductive fabric attached to a peripheral metal frame, shield  34  may be formed by combining shielding can structures with other metal structures in device  10 . As an example, shield  34  may have a first portion that is formed from a shielding can structure (or a metal frame with a fabric cover) and a second portion that is formed using part of a metal structure such as a shield for a subscriber identity module (SIM) card. In wireless devices such as cellular telephones and portable computers, SIM cards are used to authenticate wireless users to a wireless service provider. Metal shield structures are used to hold and shield SIM cards within the housing of an electronic device. By combining a SIM card shield with an adjacent shielding can, overall shielding structure volume for a given amount of shielded area may be reduced, because intervening sidewall structures can be minimized or eliminated. 
     An illustrative SIM card and SIM card shield structure are shown in  FIG. 8 . As shown in  FIG. 8 , when SIM card  52  is inserted into an opening in a SIM card shielding structure such as opening  58  in SIM card shield  60 , SIM card contacts  54  will mate with corresponding SIM card shield contacts  62 . Control circuitry  16  may have signal paths coupled to contacts  62  to support communications with the circuitry of SIM card  52 . SIM card shield  60  may have vertical sidewalls such as sidewalls  60 - 2 . Upper wall  60 - 1  may be formed from a planar sheet of metal. An opposing lower wall may be formed for shield  60  such as lower wall  60 - 1 ′ or lower wall  60 - 1 ′ may be omitted (e.g., to permit soldering of sidewalls  60 - 2  directly to a printed circuit board such as printed circuit  24 . If desired, other configurations may be used for shield  60 . The illustrative box shape of  FIG. 8  is merely illustrative. 
     Shield  60  may be configured to mate with an adjacent shield can, thereby forming an area-efficient hybrid shield for components  26 . A perspective view of an illustrative SIM card shielding structure that has portions for mating with an adjacent shield can is shown in  FIG. 9 . As shown in  FIG. 9 , SIM card shield  60  may have a planar upper surface such as surface  60 - 1  surrounded on some or all sides by sidewalls  60 - 2 . Along one or more of the sidewalls of shield  60 , horizontally protruding bent tabs  60 - 2 ′ may be formed to engage with corresponding portions of a component shield can. Tabs  60 - 2 ′ may be formed by cutting and bending sidewalls portions of shield  60  upwards to form horizontal protrusions from shield  60 . In the example of  FIG. 9 , oddly numbered tabs  60 - 2 ′ are bent upward slightly less than evenly numbered tabs  60 - 2 ′, which allows a portion of an adjacent shield can to be sandwiched between the even and odd tabs. 
     Consider, as an example, the configuration of  FIG. 10 . As shown in  FIG. 10 , shield  34  may be formed by joining SIM card shield  60  with component shielding can  64 . Shield can  64  may have a horizontally extending planar upper wall such as wall  64 - 1 . Sidewalls  64 - 2  may extend vertically downward and may be soldered to printed circuit  24 . One of the sidewalls of shield  64  (e.g., the sidewall facing SIM card shield tabs  60 - 2 ′) may be bent upwards (e.g., from vertical to horizontal), thereby forming extended horizontal wall portion  64 - 1 ′. In the example of  FIG. 10 , shield can  64  has one horizontally protruding edge (horizontally protruding upper wall portion  64 - 1 ′) and SIM card shield  60  has mating tabs  60 - 2 ′ for receiving this one protruding edge when shield can  64  is moved towards SIM card shield  60  in direction  66 . If desired, other configurations may be used for forming a hybrid shield having joined SIM card shield and shielding can structures (e.g., configurations in which shield  64  and shield  60  are joined along part of a single edge or are joined along all or part of two or more edges, configurations in which tabs are formed on shield  64  that mate with a horizontally protruding portion of shield  60 , etc.). The configuration of  FIG. 10  is merely illustrative. 
       FIG. 11  is a cross-sectional side view of shield  34  of  FIG. 10  following mating of shield  64  and shield  60  by placing shield can wall protrusion  64 - 2 ′ of upper shield wall  64 - 2  of shield can  64  between opposing upper and lower tabs  60 - 2 ′ of shield  60 . As shown in  FIG. 11 , shield  34  may be soldered to printed circuit  24  over component  26  and over SIM card  52 . Tabs  60 - 2 ′ and protrusion  64 - 2 ′ may overlap components  26 , thereby expanding the area available for shielding under shield  34 . Space may be used efficiently, because intervening vertical wall structures between component  26  and SIM card  52  may be reduced or eliminated. For example, the vertical wall associated with the edge of can  64  that is adjacent to SIM card shield  60  may be omitted. Some or all of the vertical wall of shield  60  that is adjacent to shield can  64  (i.e., wall  60 - 2  in the example of  FIG. 11 ) may also be omitted. For example, most or all of wall  60 - 2  may be bent upwards to form tabs  60 - 2 ′ with only corner post portions of wall  60 - 2  remaining. 
     It is not necessary to use both upper and lower horizontal tab protrusions from shield  60  to mate with shield can  64 .  FIG. 12  is a cross-sectional side view of protrusion  64 - 2 ′ mating with a series of upper tabs  60 - 2 ′ (or a single upper tab) in a configuration in which no lower tabs are used.  FIG. 13  is a cross-sectional side view of protrusion  64 - 2 ′ mating with a series of lower tabs  60 - 2 ′ (or a single lower tab) in a configuration in which no upper tabs are used. In general, tabs may be formed on shield  64 , shield  60 , and/or portions of both shield  60  and  64 , may be upwardly bent and downwardly bent tabs, and/or may include only lower tabs or only upper tabs. 
     In the example of  FIG. 14 , horizontal sheet metal plate  70  has been welded between a portion of shield  64  (e.g., horizontally extending wall portion  64 - 2 ′) and an adjacent portion of shield  60  (e.g., upper wall  60 - 1 ). Connections  72  may be welds formed using laser welding or other welding techniques. Solder or other conductive materials may also be used to form connections  72  to join portions  64 - 2 ′ and  60 - 1 . If desired, vertical wall  60 - 2  may be partly or completely removed to create more interior volume for shield  34  (e.g., wall  60 - 2  may be retained only at corner post locations). The portion of shield  60  to which the horizontal wall formed from sheet metal structure  70  is attached may, if desired, be a bent portion of wall  60 - 2  such as one or more tabs  60 - 2 ′. If desired, conductive fabric  46  or other conductive structures may be used to form horizontal planar wall  70  or other conductive bridging structure that couples adjacent edges of shields  64  and  60 . Conductive adhesive may be used to attach the bridging structures and other shield structures. Hybrid shields such as shields formed using shielding can and SIM card shield structures may, if desired, have upper wall openings (in the component shield and/or in the SIM card shield) that are covered with fabric  46 , as described in connection with  FIG. 6 . 
     The foregoing is merely illustrative and various modifications can be made by those skilled in the art without departing from the scope and spirit of the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20150819
Publication Date: 20170822
Grant Date: 20170822
Priority Date: 20140828
Inventors: MALEK SHAYAN
PAKULA DAVID A.
STEPHENS GREGORY N.
SLOEY JASON
Assignee: APPLE INC
CPC Classifications: [{"code": "H05K1/181", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K9/0032", "inventive": true, "first": true, "tree": "[]"}, {"code": "H05K2201/10371", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y02P70/611", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K1/0216", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K1/0216", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K9/0032", "inventive": true, "first": true, "tree": "[]"}, {"code": "Y02P70/50", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L2224/16227", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K1/181", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K9/0032", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01L2924/3025", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K2201/10371", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L23/552", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01L2924/3025", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K1/0216", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L23/552", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K2201/10371", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K1/181", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y02P70/50", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L2224/16227", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 55404287