PATENT DOCUMENT

Publication Number: US-9033716-B2
Application Number: US-201313952935-A
Country: US
Kind Code: B2

Title: Printed circuit board connectors

Abstract:
Contact pads on structures such as printed circuits may be coupled to each other using printed circuit connectors such as board-to-board connectors. A printed circuit connector may have interlocking metal frame structures. The metal frame structures may be soldered to traces on the printed circuits. Rectangular openings in the metal frame structures may receive a rectangular contact array structure that is separate from the metal frame structures. The contact array structure may include a dielectric carrier structure and an array of conductive contacts. The dielectric carrier structure may align the contacts with respect to pads on the printed circuits to which the metal frame structures are soldered. The contacts may be formed from metal spring structures or conductive elastomeric structures that are compressed between respective printed circuit contact pads when the metal frame structures of a printed circuit connector are attached to each other.

Claims:
What is claimed is: 
     
       1. A printed circuit connector for connecting first metal pads on a first structure to second metal pads on a second structure, comprising:
 a first printed circuit connector structure; 
 a second printed circuit connector structure that mates with the first printed circuit connector structure; and 
 a contact array structure interposed between the first structure and the second structure and surrounded by the first and second printed circuit connector structures so that contacts in the contact array structure make electrical connections between the first metal pads and the second metal pads. 
 
     
     
       2. The printed circuit connector defined in  claim 1  wherein the first and second printed circuit connector structures have interlocking engagement features. 
     
     
       3. The printed circuit connector defined in  claim 1  wherein the first printed circuit connector structure has protrusions and wherein the second printed circuit connector structure has openings that are configured to receive the protrusions to hold the first and second printed circuit connector structures together. 
     
     
       4. The printed circuit connector defined in  claim 1  wherein the first and second printed circuit connector structures comprise interlocking metal frames. 
     
     
       5. The printed circuit connector defined in  claim 4  wherein the interlocking metal frames comprise rectangular frames with rectangular openings. 
     
     
       6. The printed circuit connector defined in  claim 5  wherein the contact array structure has a rectangular footprint and is received within the rectangular openings. 
     
     
       7. The printed circuit connector defined in  claim 6 , wherein the contacts comprises metal members and wherein the contact array structure comprises a plastic rectangular carrier that aligns the metal members with respect to the pads. 
     
     
       8. The printed circuit connector defined in  claim 7  wherein the metal members each comprise a metal spring structure coated with a metal coating. 
     
     
       9. The printed circuit connector defined in  claim 6  wherein the contact array structure comprises an elastomeric dielectric carrier structure and wherein the contacts comprise conductive elastomeric structures embedded within the elastomeric dielectric carrier structure. 
     
     
       10. A printed circuit connector, comprising:
 a first metal frame configured to attach to a first printed circuit board that has a first array of metal contact pads; 
 a second metal frame configured to attach to a second printed circuit board that has a second array of metal contact pads; 
 a plurality of contacts interposed between the first array of metal contact pads and the second array of metal contact pads; and 
 a dielectric carrier that is separate from the first and second metal frames and that aligns the contacts with the first and second arrays of metal contact pads so that each metal contact pad in the first array of metal contact pads is shorted by a respective one of the contacts to a corresponding one of the metal contact pads in the second array of metal contact pads. 
 
     
     
       11. The printed circuit connector defined in  claim 10  wherein the contacts each comprise a metal spring. 
     
     
       12. The printed circuit connector defined in  claim 11  wherein each metal spring has a first portion configured to press against a metal contact pad in the first array and a second portion configured to press against a metal contact pad in the second array. 
     
     
       13. The printed circuit connector defined in  claim 10  wherein each contact comprises a column of elastomer impregnated with metal. 
     
     
       14. The printed circuit connector defined in  claim 10  wherein the first metal frame has a rectangular ring shape that surrounds the first array of metal contact pads and wherein the second metal frame has a rectangular ring shape that surrounds the second array of metal contact pads. 
     
     
       15. The printed circuit connector defined in  claim 14  further comprising plastic structures attached to the second metal frame, wherein the plastic structures have portions that align the dielectric carrier with respect to the second metal frame. 
     
     
       16. The printed circuit connector defined in  claim 15  wherein the dielectric carrier has openings and wherein the portions comprise plastic alignment posts that mate with the openings. 
     
     
       17. A board-to-board printed circuit connector configured to electrically connect a first set of printed circuit board pads on a first printed circuit to a second set of printed circuit board pads on a second printed circuit, the board-to-board printed circuit connector comprising:
 a first metal member configured to be soldered to the first printed circuit; 
 a second metal member configured to be soldered to the second printed circuit; and 
 a contact array structure that is separate from the first and second metal members, wherein the contact array structure includes a dielectric carrier structure that is received within openings in the first and second metal members and an array of contacts that are aligned with respect to the first and second sets of printed circuit board pads by the dielectric carrier structure. 
 
     
     
       18. The board-to-board connector defined in  claim 17  wherein the first metal member comprises protrusions and wherein the second metal member comprises holes that receive the protrusions. 
     
     
       19. The board-to-board connector defined in  claim 18  wherein the contacts comprise conductive elastomeric structures that are compressed when the holes receive the protrusions. 
     
     
       20. The board-to-board connector defined in  claim 18  wherein the contacts comprise spring structures that are compressed when the holes receive the protrusions.

Description:
BACKGROUND 
     This relates generally to connectors, and, more particularly, to printed circuit board connectors. 
     Electronic devices include integrated circuits and other components that are mounted on printed circuits. It is sometimes necessary to join the circuitry on printed circuits using connectors. For example, board-to-board connectors may be used to connect printed circuit boards to each other. 
     Board-to-board connectors generally require tight alignment during mating to avoid damage. This can make it challenging to assemble products that use such connectors. Even when extensive efforts are made to align board-to-board connectors properly, there is a risk for damage during the mating process. When damage arises during assembly, parts may need to be reworked or discarded. 
     Board-to-board connectors can be mounted on printed circuits using solder. Solder may be susceptible to corrosion if not isolated from the environment. To prevent undesired corrosion, solder joints in board-to-board connectors are often coated with a polymer coating. Masking fixtures or plastic protective caps may be used to ensure that contacts in a board-to-board connector are not exposed to polymer coating material when the solder is being coated, but the fixtures and protective caps that are available for masking board-to-board connectors tend to be complex and costly. 
     It would therefore be desirable to be able to provide improved printed circuit connectors. 
     SUMMARY 
     Circuitry on printed circuits may be interconnected using printed circuit board connectors. Printed circuits may have metal traces that are patterned to form interconnect paths and contact pads. Arrays of contact pads on printed circuits may be connected to each other using printed circuit connectors such as board-to-board connectors. 
     A printed circuit connector may have a pair of interlocking metal frame structures such as rectangular interlocking metal frames. The metal frame structures may be soldered to traces on printed circuits. Rectangular openings in the metal frame structures may receive a contact array structure that is separate from the metal frame structures. Alignment features such as plastic alignment posts on the metal frame structures may be configured to mate with corresponding recesses in the contact array structure to align the contact array structure relative to the pads on the printed circuits. 
     The contact array structure may include a dielectric carrier structure such as a rigid or elastomeric polymer structure and an array of conductive contacts. The dielectric carrier structure may align the conductive contacts with respect to the pads on the printed circuits to which the metal frame structures are soldered. The conductive contacts may be formed from metal spring structures or conductive elastomeric structures that are compressed between respective printed circuit contact pads when the metal frame structures of a printed circuit connector are attached to each other. 
     Further features, their nature and various advantages will be more apparent from the accompanying drawings and the following detailed description of the preferred embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional side view of an illustrative electronic device of the type that may use printed circuit board connectors in accordance with an embodiment. 
         FIG. 2  is an exploded perspective view of a pair of printed circuits being coupled by an illustrative printed circuit connector in accordance with an embodiment. 
         FIG. 3  is a cross-sectional side view of a pair of printed circuits being coupled by an illustrative printed circuit connector in accordance with an embodiment. 
         FIG. 4  is a perspective view of printed circuit connector structures being assembled to form a printed circuit connector in accordance with an embodiment. 
         FIG. 5  is a cross-sectional side view of a pair of structures such as printed circuits being coupled using an illustrative printed circuit connector with metal contacts in a dielectric carrier in accordance with an embodiment. 
         FIG. 6  an exploded cross-sectional side view of a pair of structures such as printed circuits being coupled using a printed circuit connector that has an elastomeric member with embedded conductive elastomeric contacts in accordance with an embodiment. 
         FIG. 7  is a cross-sectional side view of the structures and printed circuit connector of  FIG. 6  in an assembled configuration in accordance with an embodiment. 
         FIG. 8  is top view of an illustrative printed circuit carrier containing metal contacts in accordance with an embodiment. 
         FIG. 9  is a top view of a portion of an illustrative printed circuit connector having two rows of contacts in accordance with an embodiment. 
         FIG. 10  is a top view of a portion of an illustrative printed circuit connector having three rows of contacts in accordance with an embodiment. 
         FIG. 11  is a top view of a portion of an illustrative irregularly shaped printed circuit connector such as an L-shaped connector in accordance with an embodiment. 
         FIG. 12  is a top view of a portion of an illustrative square printed circuit connector in accordance with an embodiment. 
         FIG. 13  is a cross-sectional side view of printed circuit connector structures being masked during coating deposition operations using tape that is attached to the exposed outer edge of the printed circuit connector structures in accordance with an embodiment. 
         FIG. 14  is a cross-sectional side view of printed circuit connector structures being masked during coating deposition operations using a movable fixture in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic components such as integrated circuits, discrete components such as inductors, resistors, and capacitors, switches, sensors, and other circuitry may be mounted on dielectric substrates in an electronic device. Interconnects may be formed from patterned metal traces or other conductive pathways on the dielectric substrates. The dielectric substrates in an electronic device may include layers of glass, layers of plastic, molded plastic structures, printed circuits, or other dielectric substrates. 
     Printed circuit substrates may include rigid printed circuit board substrates (e.g., rigid printed circuit boards formed from fiberglass-filled epoxy) and flexible printed circuit board substrates (e.g., flex circuits formed from flexible sheets of polyimide or layers of other flexible polymer). Signal lines on the printed circuit substrates may be formed from patterned metal traces or other conductive paths. 
     Connectors may be used to couple the components and conductive paths on one substrate to the components and conductive paths on another substrate. For example, a first printed circuit such as a first rigid printed circuit board or first flexible printed circuit may be coupled to a second printed circuit such as a second rigid printed circuit board or second flexible printed circuit using a board-to-board printed circuit connector. Printed circuit connectors may also be used to couple flexible and rigid printed circuits to other components. 
     A printed circuit connector may have a first portion (sometimes referred to as a jack or female connector structure) that is attached to a first printed circuit and may have a mating second portion (sometimes referred to as a plug or male connector structure). These printed circuit board structures may engage one another when mated to form a connection. Interlocking printed circuit connectors may also be formed using symmetrical connector structures (i.e., parts that include both male and female structures). Printed circuit connectors that include a plug and a jack are sometimes described herein as an example. 
     Printed circuit connectors may be used in electronic devices that include printed circuits. An illustrative electronic device of the type that may be provided with one or more printed circuit connectors is shown in  FIG. 1 . Device  10  of  FIG. 1  may be a handheld device such as a cellular telephone or media player, a tablet computer, a notebook computer, other portable computing equipment, a wearable or miniature device such as a wristwatch or pendant device, a television, a computer monitor, a set-top box, a desktop computer, a wireless router, or other electronic equipment. 
     As shown in  FIG. 1 , electronic device  10  may include a display such as display  14 . Display  14  may be a touch screen that incorporates a layer of conductive capacitive touch sensor electrodes or other touch sensor components or may be a display that is not touch-sensitive. Display  14  may include an array of display pixels formed from liquid crystal display (LCD) components, an array of electrophoretic display pixels, an array of electrowetting display pixels, or display pixels based on other display technologies. 
     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 contain components such as display  14  and other components  16 . Components  16  may include integrated circuits, discrete components such as resistors, capacitors, and inductors, sensors, input-output devices, switches, status-indicator lights, audio components, and other circuits. 
     Components  16  may be mounted on printed circuits  18 . Printed circuits  18  may include rigid printed circuit boards, flexible printed circuits, printed circuit structures of the type that include integral flexible tails extending from sections of rigid printed circuit board material (sometimes referred to as rigid flex printed circuits), or other printed circuit structures. Anisotropic conductive film or other conductive adhesive, solder, or other conductive materials may be used in coupling electrical components  16  to printed circuits  18 . For example, anisotropic conductive film may be used to attach conductive traces on one end of a flexible printed circuit cable to display  14 . Printed circuits such as flexible printed circuits that are used to form signal buses may have few or no components  16  (as an example). 
     Printed circuit connectors  20  may be used to couple printed circuits to other structures in device  10 . For example, board-to-board connectors  20  may be used in coupling together respective printed circuits  18 . The printed circuits that are coupled together in this way in device  10  may be rigid printed circuits, flexible printed circuits, and/or rigid flex printed circuits. 
     As shown in  FIG. 1 , printed circuit connectors  20  may each have a first connector structure  22  and a mating second connector structure  24 . Mating printed circuit connector structures  22  and  24  may be provided with snaps or other interlocking engagement features to help hold the printed circuit connectors together. 
     Printed circuit connectors  20  may have an array of contacts for shorting contact pads on respective printed circuits to each other. The array of contacts may be aligned with respect to the pins using a dielectric carrier in a contact array structure. 
     The contact array structure may be received within openings in a pair of mating connector structures and may form signal paths through the connector for carrying data and/or power. For example, the contact array structure may have the shape of a rectangular box that is received within a rectangular opening formed in the interior of a pair of mating rectangular ring-shaped connector structures. When received within the rectangular opening in this way, the connector structures surround the periphery of the contact array structure. The connector structures may help align the contact array structure. 
     The contact array structure may include multiple connector contacts. The connector contacts may be formed from stamped metal structures or other metal structures that are carried by a dielectric carrier such as a plastic carrier or may be formed from conductive elastomeric contact structures that are embedded within a dielectric elastomeric structure. 
       FIG. 2  is an exploded perspective view of an illustrative connector. As shown in  FIG. 2 , connector  20  may have mating connector structures  22  and  24 . Connector structure  22  may be mounted to printed circuit  18 A. Connector structure  24  may be mounted to printed circuit  18 B. Connector structures  22  and  24  may have the shape of rectangular rings or other shapes that have openings. The openings may receive contract array structure  26  when connector  20  is assembled. 
     Metal traces in printed circuits  18 A and  18 B may be patterned to form contact pads. Contact array structure  26  may include dielectric carrier structure  28  and connector contacts  30 . Dielectric carrier structure  28  may be formed from a polymer or other dielectric that helps electrically isolate and mechanically support connector contacts  30 . Connector contacts  30  may be formed from conductive structures that short respective pairs of contact pads  32  together. Each connector contact  30  of  FIG. 2  may, for example, short a respective one of contact pads  32  on printed circuit  18 B to a corresponding one of contact pads  32  on printed circuit  18 A when connector  20  is assembled. 
     In its assembled state, connector structure  22  mates with connector structure  24  and contact array structure  26  is sandwiched between boards  18 A and  18 B and is surrounded by connector structures  22  and  24 . When structures  22  and  24  are attached to each other, contact array structure  26  is oriented so that contacts  30  short pads  32  on printed circuit  18 B to respective pads  32  on printed circuit  18 A. 
       FIG. 3  is a cross-sectional side view of printed circuits such as printed circuits  18 A and  18 B being connected together by illustrative printed circuit connector  20 . Printed circuit connector  20  of  FIG. 3  has upper printed circuit connector structure  22  and lower printed circuit connector structure  24 . Upper printed circuit connector structure  22  has been mounted on the lower surface of printed circuit  18 A using solder  40 . Solder  40  connects structure  22  to metal traces  42  on printed circuit  18 A. Lower printed circuit connector structure  22  has been mounted to metal traces  46  on printed circuit  18 B using solder  44 . 
     Printed circuit connector structures  22  and  24  may be provided with mating engagement features (e.g., interlocking mechanical features such as protrusions and recesses that hold structures  22  and  24  together). As shown in  FIG. 3 , for example, printed circuit connector structures  22  may have protruding portion such as snaps  50  and printed circuit connector structures  24  may have mating engagement features such as holes  52  or other openings. When printed circuit structure  22  is mated with printed circuit structure  24 , snaps  50  may engage holes  52  to hold connector  20  together. 
     When connector  20  is being held together by interlocking features on structures  22  and  24 , contact array structure  26  will be held in place within connector  20 . Contact array structure  26  may include dielectric carrier structure  28  and an array of conductive contacts  30 . If, as an example, there are three pads  32  on printed circuit  18 B and three corresponding pads  32  on printed circuit  18 A as shown in  FIG. 3 , contact array structure  26  may have an array of three corresponding contacts  30 . Each of connector contacts  30  may form an electrical path between a respective one of pads  32  on printed circuit  18 B and a corresponding one of pads  32  on printed circuit  18 A when printed circuit connector  20  is being used to couple printed circuits  18 A and  18 B together. 
     Circuitry such as illustrative components  16  may be mounted to printed circuits such as printed circuits  18 A and  18 B. Solder joints  38  or other conductive coupling structures may be used to couple pins  34  on components  16  to corresponding printed circuit pads  36 . Any suitable number of components  16  may be mounted to the printed circuits being joined using printed circuit connector  20 . The configuration of  FIG. 3  in which a single component  16  is mounted to printed circuit  18 A and in which a single component  16  is mounted to printed circuit  18 B is merely illustrative. 
       FIG. 4  is a perspective view of illustrative structures that may be used in forming printed circuit connector  20 . As shown in  FIG. 4 , patterned metal traces (pads)  32  and  46  may be formed on the surfaces of printed circuit boards that are to be joined using printed circuit connector  20  (e.g., on the surfaces of printed circuit boards  18 A and  18 B). Photolithography or other fabrication techniques may be used in forming patterned metal traces such as traces  32  and  46 . Traces  32  may be arranged in a pattern of contact pads that are coupled to internal signal lines (power lines, analog data lines, digital data lines, etc.) in printed circuits  18 A and  18 B. Traces  46  may be used to form solder pads in configurations that allow connector structures  22  and  24  to be soldered to printed circuits  18 A and  18 B. If desired, internal signal paths (e.g., grounding paths) in boards  18 A and  18 B may be shorted to pads  46 . 
     Following formation of patterned metal traces  32  and  46  on printed circuits  18 A and  18 B, connector structures  22  and  24  may be soldered to printed circuit boards  18 A and  18 B. Connector structures  22  and  24  may include metal frame structures and, if desired, other structures such as overmolded plastic structures. As shown in  FIG. 4 , for example, connector structure  24  may include overmolded plastic structures  66  on metal frame  62 . Metal frame  62  may have the shape of a rectangular ring that receives contact array structure  26 . Contact array structure  26  may have an array of contacts in a dielectric carrier. 
     Plastic structures  60  of connector structure  24  may have alignment features that mate with corresponding alignment features on contact array structure  26 . For example, overmolded plastic  66  may have portions forming alignment posts  60 . Alignment posts  60  may mate with corresponding alignment openings such as recesses  64  in the dielectric that makes up contact array structure  26 . 
     Metal contacts  30  may be held in place using dielectric such as plastic carrier  28  in contact array structure  26 . Metal contacts  30  may be, for example, stamped metal parts such as copper alloy pieces that have been plated or otherwise coated with a metal such as gold to help withstand corrosion. Metal contacts  30  may be press fit into slots in carrier  28  or may be formed within an overmolded version of carrier  28  (as examples). 
     During assembly of connector  20 , contact array structure  26  is interposed between printed circuits  18 A and  18 B while being received within openings in structures  22  and  24 . When connector structure  22  and connector structure  24  are successfully mated as shown on the right-hand side of  FIG. 4 , printed circuit connector  20  is formed, so that the interconnects and circuitry on printed circuit  18 A can be electrically connected to the interconnects and circuitry on printed circuit  18 B. 
     If desired, metal contacts  30  in contact array structure  26  may be formed from spring-shaped metal members or other metal structures that outwardly bias portions of contacts  30  against printed circuit contact pads  32 . This type of configuration is shown in  FIG. 5 .  FIG. 5  is a cross-sectional side view of connector  20  and printed circuits  18 A and  18 B taken along line  70  of  FIG. 4  and viewed in direction  72 . As shown in  FIG. 5 , contact  30  may include spring structures such as upper spring portion  30 - 1  and lower spring portion  30 - 2 . The metal spring structure formed from portions  30 - 1  and  30 - 2  may be formed from a conductive metal such as a copper alloy and may be coated with a metal that helps resist corrosion such as gold. When compressed between pads  32  on printed circuits  18 A and  18 B, spring portions  30 - 1  and  30 - 2  move towards each other while creating an outward biasing force that helps hold spring portion  30 - 1  against pad  32  on printed circuit  18 A and that helps hold spring portion  30 - 2  against pad  32  on printed circuit  18 B. In the illustrative configuration of  FIG. 5 , end portion  30 E of contact  30  does not form electrical connections with any metal pads  32 , but rather is used to help properly orient and secure contact  30  within plastic carrier  28  of contact array structure  26 . 
     If desired, dielectric and conductive elastomeric structures may be used in forming contact array structure  26  for printed circuit connector  20 .  FIG. 6  is an exploded side view of this type of printed circuit connector. As shown in  FIG. 6 , printed circuit connector  20  may have printed circuit connector structure  22  (e.g., a rectangular ring-shaped metal frame with protrusions  50 ) on printed circuit  18 A and may have printed circuit connector structure (e.g., a rectangular ring-shaped metal frame with mating openings  52 ) on printed circuit  18 B. Structures  22  and  24  may be configured to mate with each other. Rectangular openings in the centers of structures  22  and  24  may receive a rectangular contact array structure such as structure  26 , so that contacts  30  are aligned with respect to pads  32 . When structures  22  and  24  are mated, contact array structure  26  may be compressed between printed circuits  18 A and  18 B, so that contacts  30  electrically short pads  32  on printed circuit  18 B to corresponding pads  32  on printed circuit  18 A. 
     In the illustrative configuration of  FIG. 6 , contact array structure  26  is formed from elastomeric structures. Dielectric elastomeric structure  28  may be a carrier structure that is formed from a dielectric such as polymer foam or other elastomeric insulator. Contacts  30  may be formed from conductive structures that are embedded within dielectric elastomeric structure  28 . For example, contacts  30  may be formed from metal-impregnated elastomeric polymer structures such as silver-impregnated elastomer columns. Each conductive elastomeric structure of this type that is embedded within dielectric elastomeric carrier  28  may serve as a respective contact  30  for printed circuit connector  20 . 
     When compressed between respective pads  32  as shown in  FIG. 7 , the elastomeric material that forms contacts  30  of printed circuit connector  20  may help bias contacts  30  outwards, thereby facilitating the formation of good ohmic connections between contacts  30  and pads  32  on opposing printed circuits  18 A and  18 B. As shown in  FIG. 7 , printed circuits  18 A and  18 B may contain metal traces  80  for distributing signals from pads  32  within printed circuits  18 A and  18 B (e.g., to electrically couple the circuitry of components  16  to pads  32 ). 
       FIG. 8  is a top view of an illustrative pattern of contacts  30  that may be used in connector  20  in an embodiment in which stamped metal parts are used in forming contacts  30 . Ends  30 E of contacts  30  can be used to help hold contacts  30  in place within plastic contact carrier  28 . There are two rows of contacts  30  in the illustrative configuration of  FIG. 8 . In general, connector  20  may have a single contact  30 , multiple contacts  30 , a single row of multiple contacts  30 , two rows of one or more contacts  30 , two or more rows each with multiple contacts  30 , or any other suitable number of contacts (i.e., any suitable number of columns and rows of contacts  30  or other pattern of contacts  30 ) in contact array structure  26 . 
     In the illustrative pattern of  FIG. 9 , contact array structure  26  has two rows of contacts  30 . Contacts  30  may be metal structures (e.g., metal structures with integral springs) or elastomeric structures with embedded silver particles or other embedded conductive material to render the elastomeric structures conductive. The outline of each contact  30  on the surface of carrier  28  may have a circular shape (as shown in the  FIG. 9  example), may have a rectangular shape, may have a square shape, or may have other suitable shapes. 
       FIG. 10  shows how contact array structure  26  may have an array of contacts  30  arranged in three rows to form a rectangular array that has a more square aspect ratio than illustrative contact array structure  26  of  FIG. 9 . If desired, contact array structure  26  and connector  20  may have an irregular outline. As shown in  FIG. 11 , for example, connector  20  and contact array structure  26  may have an L-shaped footprint. Use of an L-shaped outline for contact array structure  26  may help contact array structure  26  and connector  20  accommodate nearby components such as adjacent component  16 .  FIG. 12  shows how contact array structure  26  may have a 1:1 aspect ratio (i.e., connector  20  and contact array structure  26  may have a square footprint). Use of a square outline for printed circuit connector  20  may help connector  20  form a dense set of electrical board-to-board connections (i.e., a relatively large number of connections per unit board area). 
     Printed circuit connectors  22  and  24  may have a rectangular frame shape with a rectangular opening or may have other suitable opening shapes. Tape or other structures may be used to mask the rectangular opening of each printed circuit connector while depositing a coating layer on the printed circuits to prevent solder corrosion. 
     Consider, as an example, the configuration of  FIG. 13 . In the  FIG. 13  example, printed circuit connector  24  has been attached to printed circuit  18 B by using solder  44  to solder printed circuit connector  24  to metal traces (pads)  46  on printed circuit  18 B. Solder  44  may be susceptible to corrosion. Accordingly, a protective polymer layer such as polymer coating  94  may be formed on printed circuit  18 B. As shown in  FIG. 13 , polymer coating  94  may cover solder  44  and thereby prevent solder  44  from being exposed to the environment and subjected to possible corrosion. 
     During deposition of polymer coating  94 , a masking structure such as tape  90  may be formed over rectangular opening  104  in printed circuit connector structure  24 . Tape  90  may be, for example, a sheet of polymer coated with a layer of pressure sensitive adhesive. The adhesive of tape  90  may be used to attach tape  90  to upper edge  24 E of connector structure  24 . Edge  24 E may have the shape of a rectangular ring that surrounds rectangular opening  104 . The presence of tape  90  over opening  104  during deposition of polymer coating  94  may help prevent insulating polymer coating  94  from covering and thereby contaminating the surfaces of pads  32 , which could hinder the formation of satisfactory electrical connections between contacts  30  and pads  32 . Following formation of coating layer  94 , tape  90  may be peeled off of printed circuit connector  24  by pulling upwards in direction  92  on end  90 T of tape  90  (as an example). 
       FIG. 14  shows how computer controlled fixture  100  may be placed into opening  104  of printed circuit connector  24  during deposition of polymer coating  94  to cover and thereby protect solder  44 . Fixture  100  may be formed from materials such as plastic and/or metal and may be positioned using a computer-controlled positioner. When it is desired to protect pads  32  from coating  94 , fixture  100  may be moved in direction  102  to cover pads  32  as shown in  FIG. 14 . Following formation of coating  94 , fixture  100  may be moved in direction  106  to remove fixture  100  from opening  104  of printed circuit connector structure  24 . 
     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: 20130729
Publication Date: 20150519
Grant Date: 20150519
Priority Date: 20130729
Inventors: SLOEY JASON
SEHRAWAT VARUN
Assignee: APPLE INC
CPC Classifications: [{"code": "H05K1/11", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R23/722", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01R12/716", "inventive": true, "first": true, "tree": "[]"}, {"code": "H05K3/368", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K1/111", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R12/73", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/2414", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K1/147", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K2201/10189", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R12/52", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R12/00", "inventive": true, "first": true, "tree": "[]"}, {"code": "H05K3/361", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K1/11", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K1/111", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K1/147", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R12/716", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R12/52", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K2201/10189", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K3/368", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/2414", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R12/73", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K3/361", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 52390856