PATENT DOCUMENT

Publication Number: US-9011176-B2
Application Number: US-201213492813-A
Country: US
Kind Code: B2

Title: ESD path for connector receptacle

Abstract:
Circuits, methods, and apparatus that may provide a separation between a signal ground and an enclosure ground such that EMI and ESD circuits are not bypassed. One example may provide a connector receptacle having fingers for contacting a device enclosure, where the fingers are not directly electrically connected to a shell of the connector receptacle. These fingers may be isolated from the shell along a top-side by an electrically insulating layer. These fingers may be further insulated from the shell along a back side by a nonconductive piece or portion of a housing.

Claims:
What is claimed is: 
     
       1. A connector receptacle comprising:
 a shell at least partially surrounding a housing portion; 
 at least one finger passing through a first opening in a top side of the shell and a second opening in a second side of the shell, the finger electrically insulated from the shell by the housing portion, 
 wherein the finger is electrically connected to a device enclosure, the device enclosure enclosing an electronic device supporting the connector receptacle and a first trace on a printed circuit board to form an enclosure ground, and 
 wherein the shell is electrically connected to a second trace on the printed circuit board to form a signal ground, the signal ground and the enclosure ground electrically isolated from each other. 
 
     
     
       2. The connector receptacle of  claim 1  wherein the at least one finger is electrically insulated from the shell by passing through a backside of the housing portion. 
     
     
       3. The connector receptacle of  claim 2  wherein the at least one finger is electrically insulated along a topside of the shell by a layer of tape. 
     
     
       4. The connector receptacle of  claim 3  wherein the tape is polyimide tape. 
     
     
       5. The connector receptacle of  claim 3  wherein the at least one finger is formed of phosphor bronze. 
     
     
       6. The connector receptacle of  claim 5  wherein the shell is formed using stainless steel. 
     
     
       7. The connector receptacle of  claim 3  wherein the shell and the at least one finger are soldered to a main-logic board. 
     
     
       8. The connector receptacle of  claim 7  wherein electromagnetic interference suppression circuits are electrically located between the shell and the at least one finger. 
     
     
       9. An electronic device comprising:
 an enclosure having an opening; 
 a receptacle located in the opening, the receptacle comprising:
 a shell at least partially surrounding a housing portion and having a first tab; and 
 at least one finger passing through a first opening in a top of the shell and a second opening in a second side of the shell, the finger electrically insulated from the shell by the housing portion, the finger electrically connected to the enclosure; and 
 
 a main logic board having a signal ground path electrically connected to the first tab of the shell and an enclosure ground path electrically connected to the device enclosure and the at least one finger, the signal ground and the enclosure ground electrically isolated from each other. 
 
     
     
       10. The electronic device of  claim 9  wherein the at least one finger is electrically insulated from the shell by passing through a backside of the housing portion. 
     
     
       11. The electronic device of  claim 10  wherein the at least one finger is electrically insulated along a topside of the shell by a layer of tape. 
     
     
       12. The electronic device of  claim 11  wherein the tape is polyimide tape. 
     
     
       13. The electronic device of  claim 11  wherein the at least one finger is formed of phosphor bronze. 
     
     
       14. The electronic device of  claim 13  wherein the shell is formed using stainless steel. 
     
     
       15. The electronic device of  claim 9  wherein electromagnetic interference suppression circuits are electrically located between the shell and the at least one finger. 
     
     
       16. A method of routing grounds comprising:
 providing a signal ground path comprising a faceplate of a receptacle, a shell of the receptacle, a first contact of the receptacle, and a first trace on a main-logic board, wherein the faceplate of the receptacle, the shell of the receptacle, the first contact of the receptacle, and the first trace on the main-logic board are electrically connected; and 
 providing an enclosure ground comprising a device enclosure, at least one finger of the receptacle, and a second trace on the main-logic board, wherein the device enclosure, the at least one finger, and the second trace on the main-logic board are electrically connected, 
 wherein the signal ground path and the enclosure ground are electrically isolated. 
 
     
     
       17. The method of  claim 16  further comprising providing electrostatic discharge and electromagnetic interference circuitry between the first trace and the second trace on the main-logic board. 
     
     
       18. The method of  claim 17  wherein the at least one finger of the receptacle passes through an opening in the shell of the receptacle. 
     
     
       19. The method of  claim 16  wherein a tab of the shell of the receptacle is soldered to the first trace on the main-logic board. 
     
     
       20. The method of  claim 16  wherein the at least one finger of the receptacle is soldered to the second trace on the main-logic board. 
     
     
       21. The connector receptacle of  claim 1  wherein the second side is a bottom side. 
     
     
       22. The connector receptacle of  claim 21  wherein at least one finger comprises a first portion angled along the top side of the shell. 
     
     
       23. The electronic device of  claim 9  wherein the second side is a bottom side. 
     
     
       24. The electronic device of  claim 23  wherein at least one finger comprises a first portion angled along the top side of the shell. 
     
     
       25. The connector receptacle of  claim 1  further comprising a first contact, the first contact electrically connected to the shell. 
     
     
       26. The electronic device of  claim 9  further comprising a first contact, the first contact electrically connected to the shell.

Description:
BACKGROUND 
     The number and types of electronic devices available to consumers have increased tremendously the past few years, and this increase shows no signs of abating. Devices such as portable computing devices, tablet, desktop, and all-in-one computers, cell, smart, and media phones, storage devices, portable media players, navigation systems, monitors and other devices have become ubiquitous. 
     These devices often receive power and share data using various cables. These cables may have connector inserts, or plugs, on each end. The connector inserts may plug into connector receptacles on electronic devices, thereby forming one or more conductive paths for signals, power, and ground. 
     These signals are voltages that may vary relative to a ground line. The ground line may be referred to as signal ground. One or more signal grounds may be conveyed in a cable along with signals and supply voltages. 
     These signal grounds may become noisy. For example, frequency components from signals carried in the cable may corrupt the signal ground. Reflections caused by mismatched terminations may also degrade the quality of the ground. Also, signals outside the cable may send frequency components that are carried by the signal ground. 
     Enclosures or cases for electronic devices are often connected to ground. If a noisy signal ground connects to the device enclosure, the noise from the signal ground may radiate throughout the device, thereby degrading device performance. 
     To prevent this, circuitry to suppress electromagnetic interference (EMI) may be placed between a signal ground and an enclosure ground. But this circuitry may be bypassed if a signal ground is directly connected to the device enclosure. 
     Thus, what is needed are circuits, methods, and apparatus that may provide a separation between a signal ground and an enclosure ground such that EMI circuits are not bypassed. 
     SUMMARY 
     Accordingly, embodiments of the present invention may provide circuits, methods, and apparatus that may provide a separation between a signal ground and an enclosure ground such that EMI circuits are not bypassed or shorted out. 
     An illustrative embodiment of the present invention may provide a connector receptacle having fingers for contacting a device enclosure, where the fingers are not directly electrically connected to a shell of the connector receptacle. In a specific embodiment of the present invention, these fingers are isolated from the shell along a top-side by an electrically insulating layer. This layer may be formed of a tape, such as polyimide tape, which may also be referred to as Kapton® tape, or more commonly, electrical tape. These fingers may be further insulated from the shell along a back side by a nonconductive piece or portion of a housing. This piece or housing portion may be formed of plastic, nylon, or other nonconductive material. 
     Another illustrative embodiment of the present invention may provide a connector receptacle having a faceplate that mates with a corresponding attraction plate on a connector insert. The attraction plate and faceplate may form part of an electrical path for a signal ground. The faceplate may electrically connect to a remaining portion of a shell of the connector receptacle. The shell may then electrically connect to a signal ground connection on a main-logic or other board. This board may be a printed circuit board, flexible circuit board, or other appropriate substrate. 
     The connector receptacle may further include fingers to make electrical contact with a device enclosure. These fingers may be electrically isolated from the shell of the connector receptacle. Again, these fingers are isolated from the shell along a top-side by an electrically insulating layer, which may be formed of tape or other electrically insulative material. These fingers may be further insulated from the shell along a back side by a nonconductive piece or portion of a housing, which may be formed of plastic or other electrically insulative material. These fingers may then electrically connect to an enclosure ground connection on the main-logic or other board. EMI circuits may then be placed between the signal ground and the enclosure ground. Electrostatic discharge (ESD) circuits, such as a spark-gap, Zener diode, or other ESD circuit may also be located between the signal ground and enclosure ground. 
     In various embodiments of the present invention, the connector receptacle may include one or more ground contacts. These ground contacts may be electrically connected to the signal ground of the faceplate and shell, or they may be connected to other grounds. 
     In various embodiments of the present invention, different materials may be used for portions of the connector receptacle. For example, the fingers may be formed using a highly conductive material, such as phosphor bronze or other material. The faceplate of the receptacle may be formed of a ferromagnetic steel, other magnetically conductive material, or other electrically conductive material. The remaining portion of the shell may be formed of non-magnetically conductive steel. In a specific embodiment of the present invention, label 1210 may be low-carbon steel, such as 10-10 steel. These portions may be plated with nickel, and then plated with platinum nickel. 
     Embodiments of the present invention may provide connector receptacles consistent with various standard and proprietary communication interfaces. For example, embodiments of the present invention may provide connector receptacles consistent with Universal Serial Bus (USB), High-Definition Multimedia Interface (HDMI), Digital Visual Interface (DVI), DisplayPort, Thunderbolt, and other types of interfaces. 
     Embodiments of the present invention may provide connector receptacles for use in many types of devices. For example, connector receptacles consistent with embodiments of the present invention may be employed in portable computing devices, tablet, desktop, and all-in-one computers, cell, smart, and media phones, storage devices, portable media players, navigation systems, monitors, and other devices. 
     Various embodiments of the present invention may incorporate one or more of these and the other features described herein. A better understanding of the nature and advantages of the present invention may be gained by reference to the following detailed description and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a portion of an electronic device that may be improved by the incorporation of an embodiment of the present invention; 
         FIG. 2  illustrates an electrical diagram for ground connections for a connector receptacle according to an embodiment of the present invention; 
         FIG. 3  illustrates a connector receptacle according to an embodiment of the present invention; 
         FIG. 4  illustrates a rear view of a connector receptacle according to an embodiment of the present invention; 
         FIG. 5  illustrates a cutaway view of a connector receptacle according to an embodiment of the present invention; 
         FIG. 6  illustrates a top view of a connector receptacle according to an embodiment of the present invention; and 
         FIG. 7  illustrates a side view of a connector receptacle according to an embodiment of the present invention. 
     
    
    
     DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
       FIG. 1  illustrates a portion of an electronic device that may be improved by the incorporation of an embodiment of the present invention. This figure, as with the other included figures is shown for illustrative purposes and does not limit either the possible embodiments of the present invention or the claims. 
     This example illustrates a portion of a device having an enclosure or case  110 . Enclosure or case  110  may have an opening for a connector receptacle  120 . Connector receptacle  120  may include faceplate  130 . Mesa  140  may extend from faceplate  130  and may include a number of contacts  150 . 
     In a specific embodiment of the present invention, one or more contacts  150  may be ground contacts. Also, faceplate  130  and device enclosure  110  may be grounded as well. In such an embodiment, faceplate  130  and one or more contacts  150  may be signal grounds. These signal grounds may be connected together. 
     In this example, connector receptacle  120  may be a magnetic connector receptacle, specifically a MagSafe connector receptacle. Other embodiments of the present invention may provide connector receptacles consistent with various standard and proprietary communication interfaces. For example, embodiments of the present invention may provide connector receptacles consistent with Universal Serial Bus (USB), High-Definition Multimedia Interface (HDMI), Digital Visual Interface (DVI), DisplayPort, Thunderbolt, and other types of interfaces. 
     Embodiments of the present invention may provide connector receptacles for use in many types of devices. For example, connector receptacles consistent with embodiments of the present invention may be employed in portable computing devices, tablet, desktop, and all-in-one computers, cell, smart, and media phones, storage devices, portable media players, navigation systems, monitors, and other devices. 
     Again, these signal grounds may become corrupted by various sources. For example, the power supply providing power and signal ground may be generated by a noisy power supply source. Also, other signals received or transmitted at connector receptacle  120  may corrupt the signal grounds. Signals not associated with connector receptacle  120  may transmit frequency components that are received by the signal grounds. These various signals may be improperly terminated, thereby causing reflections which may also couple to and cropped the signal grounds. If these noisy signal grounds are coupled directly to device enclosure  110 , they may propagate through device enclosure  110  and radiate onto other circuits inside or associated with the electronic device. 
     Accordingly, embodiments of the present invention may provide connector receptacles that isolate signal grounds on contacts  150  and faceplate  130  from enclosure ground  110 . By isolating these ground lines, EMI suppression and ESD circuits may be provided between these ground lines. The EMI suppression circuits may protect noise on a signal grounds from coupling to a device enclosure. The ESD circuits may help prevent electrostatic discharges at connector receptacle  120  from damaging circuitry inside device enclosure  110 . An electrical diagram of illustrative circuitry is shown in the following figure. 
       FIG. 2  illustrates an electrical diagram for ground connections for a connector receptacle according to an embodiment of the present invention. Again, a faceplate ground  130  may connect to one of ground contacts  150 . Shell ground  132  for the receptacle may also connect to the faceplate ground  130  and ground contact  150 . These grounds may be referred to as signal grounds  250 . 
     A finger ground provided by a finger, which is shown below, may connect to enclosure ground  110 . Again, EMI and ESD circuits  260  and  270  may be electrically located between signal grounds  250  and the enclosure ground  110 . In this case, a spark gap may be used for ESD protection. Examples of spark gaps that may be used may be found in co-pending U.S. patent application Ser. No. 13/033,542, filed Feb. 23, 2011, titled SPARK GAP FOR HIGH-SPEED CABLE CONNECTORS, which is incorporated by reference. Other ESD circuits  260  may be used consistent with embodiments of the present invention, including diodes, Zener diodes, resistors, and other circuits and components. Circuitry shown for EMI circuits  270  are merely illustrative, other circuitry may be used. Electrostatic discharges at a ground contact  150  or faceplate  130  may be dissipated to enclosure ground  110  through spark gap  260 . Noise on signal grounds  250  may be suppressed by EMI circuits  270  before they reach enclosure ground  110 . 
     In a specific embodiment of the present invention, the receptacle is isolated from the enclosure by a finger that passes through, but does not electrically connect to, the connector receptacle shell. An example is shown in the following figure. 
       FIG. 3  illustrates a connector receptacle according to an embodiment of the present invention. This connector receptacle includes faceplate  130 . Mesa  140  may extend from face plate  130  and may include a number of contacts  150 . Shell  132  may connect to faceplate  130 . Fingers  210  may be separated from shell  132  by area  410 . Area  410  may be covered with an electrically insulating material. In a specific embodiment of the present invention, polyimide or electrical tape may be used. In this way, if finger  210  is pushed down, it does not form an electrical connection with shell  132  or internal structures in the connector receptacle. Again, if finger  210  were to contact shell  132 , ESD and EMI components  260  and  270  would be bypassed or shorted out. 
     In various embodiments of the present invention, these internal structures or components may include magnets, magnetic shunts, contacts, or other components or structures. More detailed examples may be found in co-pending U.S. patent application Ser. No. 13/458,853, filed Apr. 27, 2012, titled MAGNETIC INSERT AND RECEPTACLE FOR CONNECTOR SYSTEM, which is incorporated by reference. 
       FIG. 4  illustrates a rear view of a connector receptacle according to an embodiment of the present invention. In this example, the connector receptacle resides on a main-logic board  450 . Main-logic board  450  may be a printed circuit board, flexible circuit board, or other appropriate substrate. 
     Fingers  210  may pass through openings  422  and shell  132  and emerge as tabs  212 . Shell  132  may include tabs  132 . Fingers  210  may be electrically isolated from shell  132  and internal components of the connector receptacle by tape  410 . Fingers  210  may be further isolated from shell  132  and internal components by plastic piece or housing portion  420 . 
     When located in an electronic device, fingers  210  may contact a surface of device enclosure  110 . Fingers  210  may also contacts one or more traces on main-logic board  450  via tab  212 , which is the portion of finger  210  extending below the connector receptacle, as shown. Shell  132  may also contact one or more traces on main-logic board  450  via tabs  132 . 
       FIG. 5  illustrates a cutaway view of a connector receptacle according to an embodiment of the present invention. In this example, polyimide or electrical tape  410  is shown as covering a substantial portion of a top of the internal components of a connector receptacle. Again, as fingers  210  are depressed, tape  410  may prevent them from coming to contact with structures and components internal to the connector receptacle. 
       FIG. 6  illustrates a top view of a connector receptacle according to an embodiment of the present invention. Again, fingers  210  may be electrically isolated from shell  132  by housing piece or portion  420 . Housing piece or portion  420  may be plastic, nylon, or other electrically nonconductive material. 
       FIG. 7  illustrates a side view of a connector receptacle according to an embodiment of the present invention. Again, fingers  410  are electrically isolated from shell  132  by housing piece or portion  420 . Shell  132  may connect to main-logic board  450  via tabs  134 . Fingers  210  may electrically connect to main-logic board  450  via tabs  212 . Contacts  150  may connect to main-logic board  450  via tabs  152 . Again, EMI and ESD components may be electrically connected between traces connected to tabs  212  and  134 . 
     By electrically isolating the signal ground from the enclosure ground, ESD and electrical noise performance may be improved. Specifically, ESD and EMI components  260  and  270  are not shorted out or bypassed. Instead, ESD circuitry  260  may protect electronic device circuitry from electrostatic discharges at the faceplate  130  or ground contacts  132 . Also, EMI circuitry  270  may suppress noise on signal grounds  250  and help prevent such noise from reaching the device enclosure  110 , from which it would otherwise radiate noise to circuitry in the electronic device. 
     The above description of embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form described, and many modifications and variations are possible in light of the teaching above. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. Thus, it will be appreciated that the invention is intended to cover all modifications and equivalents within the scope of the following claims.

Metadata:
Filing Date: 20120609
Publication Date: 20150421
Grant Date: 20150421
Priority Date: 20120609
Inventors: TZIVISKOS GEORGE
GAO ZHENG
Assignee: APPLE INC
CPC Classifications: [{"code": "H01R13/65802", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R23/6873", "inventive": true, "first": true, "tree": "[]"}, {"code": "H05K5/0247", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01R13/6594", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K9/0066", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K9/0067", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K5/0247", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/6594", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/6205", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/6596", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/658", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R12/00", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01R12/00", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01R13/658", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K9/0067", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/6596", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/6205", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K9/0066", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 49715121