Patent Publication Number: US-10320131-B2

Title: Recessed switched test connector

Description:
BACKGROUND 
     Modern computing devices incorporate increasingly complex and compact circuit boards, which may incorporate various wireless communication components (e.g., Wi-Fi, Bluetooth, and long-term evolution (LTE) components) amongst other electronic components. In various implementations, the wireless communication components may need to be calibrated, compliance tested (e.g., comply with Federal Communications Commission (FCC) emissions standards), inspected for further product development, and/or interference tested (collectively referred to herein as certification testing). 
     A test port is often included within each circuit board to perform the certification testing during commissioning of an associated device. However, such test ports typically protrude from a component-side of the circuit board, but are inaccessible once a screen is attached to the device. Alternatively, some test ports protrude from a side of the circuit board opposite the circuit board components (i.e., the non-component side). However, these test ports may create physical interference issues with other nearby components of the computing device (e.g., the device case). 
     SUMMARY 
     Implementations described and claimed herein provide a printed circuit board comprising a substrate including an aperture, an array of components attached to a first side of the substrate, and a recessed switched test connector oriented within the aperture. The recessed switched test connector includes a test port accessible from a second side of the substrate and a bracket securing the recessed switched test connector within the aperture. 
     Implementations described and claimed herein further provide a method of using a recessed switched test connector. The method includes inserting a test probe into a test port of the recessed switched test connector and testing a circuit connected from the recessed switched test connector to the test probe for interference. Further, the recessed switched test connector is oriented within an aperture in a printed circuit board substrate and the recessed switched test connector is accessible from a side of the substrate opposite an array of printed circuit board components attached to the substrate. 
     Implementations described and claimed herein still further provide a computing device comprising a printed circuit board, a display, and a case. The printed circuit board includes a substrate including an aperture, an array of components attached to a first side of the substrate, and a recessed switched test connector oriented within the aperture. The recessed switched test connector includes a test port accessible from a second side of the substrate and a bracket securing the recessed switched test connector within the aperture. The display resides in close proximity to the first side of the substrate. The case resides in close proximity to the second side of the substrate and includes a test aperture axially aligned with the test port permitting access to the test port from outside the computing device. 
     Other implementations are also described and recited herein. This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Descriptions. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. 
    
    
     
       BRIEF DESCRIPTIONS OF THE DRAWINGS 
         FIG. 1  illustrates a tablet computer and an elevation sectional view of an associated printed circuit board incorporating an example recessed switched test connector. 
         FIG. 2  is a first perspective view of an example recessed switched test connector. 
         FIG. 3  is a second perspective view of an example recessed switched test connector. 
         FIG. 4  is an elevation sectional view of an example recessed switched test connector. 
         FIG. 5  illustrates example operations for installing a recessed switched test connector on a printed circuit board and using the recessed switched test connector to perform certification testing on the printed circuit board. 
     
    
    
     DETAILED DESCRIPTIONS 
     Increasingly smaller computing devices necessitate other components of a computing device to be mounted very close to the circuit board and conventional test ports can become a limiting factor. The presently disclosed recessed test connectors reduce or eliminate protrusion of the test port on a non-component side of a printed circuit board, while providing access to the test port from the non-component side of the printed circuit board. 
       FIG. 1  illustrates a tablet computer  102  and an elevation sectional view A-A of an associated printed circuit board (PCB)  104  incorporating an example recessed switched test connector  100 . The tablet computer  102  includes a display  106  (e.g., a touchscreen, liquid crystal (LCD), light-emitting diode (LED), or organic light-emitting diode (OLED) screens) occupying a front-facing portion of the tablet computer  102  and a case  108  occupying a rear-facing portion of the tablet computer  102 . The display  106  and the case  108  in combination encompass the printed circuit board  104  within the tablet computer  102 . View A-A of the tablet computer  102  is a cross section cut along section lines A-A. 
     The printed circuit board  104  includes a variety of electronic components (e.g., component  114 ), which may be microprocessors, integrated circuits, resistors, transistors, capacitors, electronic storage devices, and/or cooling components. The electronic components are mounted on a component side (or first side)  110  of the circuit board  104  and soldered or otherwise electrically connected to a network of conductive tracks, pads, and other conductive features. The conductive network is etched from one or more conductive sheets laminated onto a non-conductive substrate  116 . As a result, the component side  110  of the substrate  116  includes protruding electronic components, while a non-component side (or second side)  112  of the substrate  116  contains few, if any, protruding components. 
     The recessed switched test connector  100  resides within an aperture  118  in the printed circuit board  104 . The recessed switched test connector  100  protrudes beyond the substrate  116  on the component side  110  of the substrate  116 , but does not substantially protrude beyond the substrate  116  (e.g., the recessed switched test connector  100  is substantially flush with an outer surface of the substrate  116  or is set back into the substrate  116 ) on the non-component side  112  of the substrate  116 . Further, a test port (not shown, see e.g., test port  232  of  FIG. 2 ) of the recessed switched test connector  100  is oriented facing the case  108 . In various implementations, a magnitude that the various components of the printed circuit board  104  protrude beyond the substrate  116  on the component side  110  of the substrate  116  is greater than the magnitude that the recessed switched test connector  100  protrudes beyond the substrate  116  on the component side  110  of the substrate  116 . 
     The display  106  resides in close proximity to (i.e., within 3.00-4.00 mm, or less) or in contact with the printed circuit board  104  on its component side  110 . The case  108  resides in close proximity to (i.e., less than 0.25 mm) or in contact with the printed circuit board  104  on its non-component side  112 . For comparison, in traditional switched connectors the display  106  and/or the case  110  may be spaced 0.80-1.00 mm from the printed circuit board  104 . The case  108  further includes a test aperture  120  that is axially aligned with the test port so that a user may access the test port from the exterior of the tablet computer  102  to perform certification testing (e.g., calibration, compliance testing (e.g., compliance with Federal Communications Commission (FCC) emissions standards), inspection for further product development, and/or interference testing). In various implementations, the certification testing accesses or sends a RF signal via the recessed switched test connector  100 . 
     A user may selectively insert an associated test probe  122  through the test aperture  120  and into the test port to perform the certification testing on the tablet computer  102 . The recessed switched test connector  100  is automatically activated when the test probe  122  is inserted into the test port and de-activated when the test probe  122  is removed from the test port. More specifically, an electrical circuit runs through the recessed switched test connector  100  during normal operation of the tablet computer  102 . When the test probe  122  is inserted into the test port, the test probe  122  mechanically and electrically disrupts the electrical circuit and diverts a signal running through the electrical circuit to the test probe  122  for the certification testing and analysis. When the test probe  122  is removed from the test port, the electrical circuit is mechanically and electrically returned to its original condition where the electrical circuit runs through the recessed switched test connector  100 . 
     In various implementations, an impedance of the test port may substantially match an impedance of the test probe  122 , which in turn may substantially match an impedance within an associated coaxial cable  144 . Impendence may be affected by the cross sectional area of a central conductor  146  and an outer conductor  147  of each of the test probe  122  and the coaxial cable  144 , as well as the distance between the two conductors  146 ,  147  and the material selection for each of the conductors  146 ,  147 . In various implementations, a substantially matching impedance has less than 5% variation in diameter. As a result, there may be little to no impedance change along a length of the test probe  122 . 
     In some implementations, the test aperture  120  is covered (e.g., with a friction-fit plug, not shown) after the certification testing on the tablet computer  102  is complete. The plug may prevent contaminates from entering the test aperture  120  when the tablet computer  102  is placed into service and may provide an improved visual or tactile experience to an end user by hiding the test aperture  120  from the end user. 
     While the tablet computer  102  is shown and described in detail above, the printed circuit board  104  and the recessed switched test connector  100 , or other recessed switched test connectors described herein, may be incorporated into a variety of other computing devices (e.g., laptop computers, personal computers, gaming devices, smart phones, or other devices that carry out one or more specific sets of arithmetic and/or logical operations) with a variety of physical forms, including various sizes and shapes. 
       FIG. 2  is a first perspective view of an example recessed switched test connector  200 . The recessed switched test connector  200  resides within an aperture  218  in a substrate  216  of an associated printed circuit board. The recessed switched test connector  200  protrudes beyond the substrate  216  on a component side (not shown) of the substrate  216 , but does not substantially protrude beyond the substrate  216  (e.g., the recessed switched test connector  200  is substantially flush with an outer surface of the substrate  216  or is set back into the substrate  216 ) on the depicted non-component side of the substrate  216 . 
     The recessed switched test connector  200  includes a test port  232  facing the non-component side of the substrate  216 . The test port  232  is used for selectively inserting a test probe (not shown, see e.g., test probe  122  of  FIG. 1 ) to perform certification testing and analysis on the printed circuit board. The recessed switched test connector  200  is automatically activated when the test probe is inserted into the test port  232  and de-activated when the test probe is removed from the test port  232 . More specifically, an electrical circuit runs through the recessed switched test connector  200  between tabs  228 ,  230  during normal operation of the printed circuit board. When the test probe is inserted into the test port  232 , the test probe mechanically and electrically disrupts the electrical circuit and diverts a signal running through the electrical circuit to the test probe for performing the certification testing and analysis. Depending on the direction of current flow, this disrupted signal may run from either tab  228  or tab  230  to the test probe. When the test probe is removed from the test port  232 , the electrical circuit is mechanically and electrically returned to its original condition where the electrical circuit runs through the recessed switched test connector  200 . 
     The recessed switched test connector  200  further includes a mounting bracket  224 , which mounts the recessed switched test connector  200  to the depicted non-component side of the substrate  216  via one or more mounting tabs (e.g., tab  226 ) and physically secures the recessed switched test connector  200  in place. The mounting tabs are soldered, adhered, or mechanically fastened to the substrate  216  and the mounting bracket  224  forms an integral part of the recessed switched test connector  200 . In some implementations, the mounting bracket  224  also serves as an electrical ground for the recessed switched test connector  200  and is electrically connected to ground on the printed circuit board. 
       FIG. 3  is a second perspective view of an example recessed switched test connector  300 . The recessed switched test connector  300  resides within an aperture  318  in a substrate  316  of an associated printed circuit board. The recessed switched test connector  300  protrudes beyond the substrate  316  on the depicted component side of the substrate  316 , but does not substantially protrude beyond the substrate  316  (e.g., the recessed switched test connector  300  is substantially flush with an outer surface of the substrate  316  or is set back into the substrate  316 ) on a non-component side (not depicted) of the substrate  316 . 
     The recessed switched test connector  300  includes a test port (not shown) facing the non-component side of the substrate  316 . The test port is used for selectively inserting a test probe (also not shown, see e.g., test probe  122  of  FIG. 1 ) to perform certification testing and analysis on the printed circuit board. The recessed switched test connector  300  is automatically activated when the test probe is inserted into the test port and de-activated when the test probe is removed from the test port. More specifically, an electrical circuit runs through the recessed switched test connector  300  between two tabs (e.g., tab  328 ) during normal operation of the printed circuit board. When the test probe is inserted into the test port, the test probe mechanically and electrically disrupts the electrical circuit and diverts a signal running through the electrical circuit to the test probe for performing the certification testing and analysis. Depending on the direction of current flow, this disrupted signal may run from either of two tabs electrically connecting the recessed switched test connector  300  to the test probe. When the test probe is removed from the test port, the electrical circuit is mechanically and electrically returned to its original condition where the electrical circuit runs through the recessed switched test connector  300  via the tabs. 
     The recessed switched test connector  300  further includes a mounting bracket  324 , which mounts and physically secures the recessed switched test connector  300  to the substrate  316 . The mounting bracket  324  includes an array of stanchions (e.g., stanchion  333 ) that extend through respective holes (e.g., hole  334 ) in the substrate  316  and may terminate with plain ends or tabs on the non-component side of the substrate  316 . The tabs or plain ends of the stanchions are soldered, adhered, or mechanically fastened to the substrate  316  (on either or both of the component side and the non-component side) and the mounting bracket  324  forms an integral part of the recessed switched test connector  300 . In some implementations, the mounting bracket  324  also serves as electrical ground for the recessed switched test connector  300  and is electrically connected to ground on the printed circuit board. 
     The recessed switched test connector  300  may possess a sandwich-type construction with the mounting bracket  324  forming a first half of the recessed switched test connector  300  and a bottom plate  336  forming a second half of the recessed switched test connector  300 . The bottom plate  336  is crimped onto the mounting bracket  324  via four crimping tabs (e.g., crimping tab  338 ). Internal components of the recessed switched test connector  300  (e.g., the electrical circuit that runs through the recessed switched test connector  300 ) may be compressively secured between the mounting bracket  324  and the bottom plate  336  within the recessed switched test connector  300 . 
     An example sectional view of the recessed switched test connector  300  is cut along section lines B-B and illustrated as recessed switched test connector  400  of  FIG. 4 . 
       FIG. 4  is an elevation sectional view of an example recessed switched test connector  400 . The recessed switched test connector  400  resides within an aperture  418  in a substrate  416  of an associated printed circuit board. The recessed switched test connector  400  protrudes beyond the substrate  416  on a component side  410  of the substrate  416 , but does not substantially protrude beyond the substrate  416  (e.g., the recessed switched test connector  400  is substantially flush with an outer surface of the substrate  416  or is set back into the substrate  416 ) on a non-component side  412  of the substrate  416 . 
     The recessed switched test connector  400  includes a test port  432  facing the non-component side  412  of the substrate  416 . The test port  432  is used for selectively inserting a test probe (not shown, see e.g., test probe  122  of  FIG. 1 ) to perform certification testing and analysis on the printed circuit board. The recessed switched test connector  400  is automatically activated when the test probe is inserted into the test port  432  and de-activated when the test probe is removed from the test port  432 . More specifically, an electrical circuit or path runs through the recessed switched test connector  400  between tabs  428 ,  430  during normal operation of the printed circuit board. When the test probe is inserted into the test port  432 , the test probe elastically deflects contact  438  creating an opening in the circuit at point  440  and concurrently completing a new testing circuit between the tab  430  and the test probe for performing the certification testing and analysis. When the test probe is removed from the test port, the contact  438  elastically returns to the depicted position in physical and electrical continuity with the tab  428  at point  440 . In various implementations, the test port  432  includes a self-centering countersink for the associated test probe, as illustrated. 
     The recessed switched test connector  400  further includes a mounting bracket  424 , which mounts and physically secures the recessed switched test connector  400  to the substrate  416 . The mounting bracket  424  includes an array of stanchions (e.g., stanchion  433 ) that extend through respective holes (not shown) in the substrate  416  and may terminate with plain ends or tabs on the non-component side of the substrate  416 . The tabs or plain ends of the stanchions are soldered, adhered, or mechanically fastened to the substrate  416  (on either or both of the component side  410  and the non-component side  412 ) and the mounting bracket  424  forms an integral part of the recessed switched test connector  400 . In some implementations, the mounting bracket  424  also serves as electrical ground for the recessed switched test connector  400  and is electrically connected to ground on the printed circuit board. 
     In some implementations, the recessed switched test connector  400  possesses a sandwich-type construction with the mounting bracket  424  forming a first half of the recessed switched test connector  400  and a bottom plate  436  forming a second half of the recessed switched test connector  400 . The bottom plate  436  is crimped onto the mounting bracket  424  via crimping tabs (e.g., crimping tab  439 ). Internal components of the recessed switched test connector  400  (e.g., the electrical circuit that runs through the recessed switched test connector  400 ) are compressively secured between the mounting bracket  424  and the bottom plate  436  within the recessed switched test connector  400 . 
     In some implementations, the bottom plate  436  also forms a ground portion of the test port  432  allowing a ground portion of a corresponding coaxial cable extending from the test probe to be grounded directly to the recessed switched test connector  400 . An insulating portion  442  of the test port  432  separates the grounded bottom plate from the electrical circuit running through the recessed switched test connector  400 . 
     In various implementations, an impedance of the test port  432  may substantially match an impedance of the test probe, which in turn may substantially match an impedance within an associated coaxial cable. Impendence may be affected by the cross-sectional area of a central conductor and an outer conductor of each of the test probe and the coaxial cable, as well as the distance between the two conductors and the material selection for each of the conductors. 
     While in some implementations, view B-B of the recessed switched test connector  400  of  FIG. 4  is a sectional view of the recessed switched test connector  300  of  FIG. 3  cut along section lines B-B, in other implementations, the recessed switched test connector  300  of  FIG. 3  and the recessed switched test connector  400  of  FIG. 4  are distinct implementations with distinct features. 
       FIG. 5  illustrates example operations  500  for installing a recessed switched test connector on a printed circuit board and using the recessed switched test connector to perform certification testing on the printed circuit board. A creating operation  505  creates an aperture in a substrate for the recessed switched test connector. The creating operation  505  may be performed by drilling, milling, cutting, or otherwise removing material from the substrate. A size of the created aperture is defined by a size of the recessed switched test connector that will be oriented therein. The substrate forms a structure and electronic network for a variety of electronic components mounted on a component side of the printed circuit board. A non-component side of the printed circuit board includes few, if any, such electronic components. 
     An orienting operation  510  orients the recessed switched test connector within the aperture. The recessed switched test connector is oriented such that an associated test port faces the non-component side of the printed circuit board and is recessed within the aperture. In various implementations, a portion of the recessed switched test connector may protrude out of the component side of the printed circuit board. 
     An attaching operation  515  attaches a bracket associated with the recessed switched test connector to the substrate securing the recessed switched test connector in place within the aperture. In some implementations, the bracket extends through the aperture and is attached to the non-component side of the substrate. In other implementations, the bracket includes a set of stanchions that extend through dedicated holes in the substrate and are attached to either or both of the component side and the non-component side of the substrate. In various implementations, the bracket is soldered, welded, glued, or mechanically attached (e.g., screwed) to the substrate. 
     An inserting operation  520  inserts a test probe into a test port of the recessed switched test connector. The recessed switched test connector is automatically activated when the test probe is inserted into the test port. More specifically, an electrical circuit runs through the recessed switched test connector between two tabs or other contacts during normal operation of the printed circuit board. When the test probe is inserted into the test port, the test probe elastically deflects a contact within the recessed switched test connector creating an opening in the circuit and concurrently completing a new testing circuit between one of the tabs or contacts with the printed circuit board and the test probe. In various implementations, the test port may have a countersunk shape to guide the test probe into the test port. 
     A certification testing operation  525  calibrates, compliance tests (e.g., compliance with Federal Communications Commission (FCC) emissions standards), inspects for further product development, and/or interference tests a circuit connected through the recessed switched test connector. In various implementations, the testing operation  525  tests radio-frequency (RF) or other types of signals. 
     A removing operation  530  removes the test probe from the test port. The recessed switched test connector is automatically de-activated when the test probe is removed from the test port. More specifically, the contact within the recessed switched test connector elastically returns to its original position in physical and electrical continuity with the tab electrically connected to the printed circuit board. In various implementations, the inserting operation  520  and the removing operation  530  are selectively performed by a user or a machine during certification of the printed circuit board. 
     The logical operations described herein are referred to variously as operations or steps. Furthermore, the logical operations may be performed in any order, adding or omitting operations as desired, unless explicitly claimed otherwise or a specific order is inherently necessitated by the claim language. 
     An example printed circuit board according to the presently disclosed technology includes a printed circuit board comprising a substrate including an aperture, an array of components attached to a first side of the substrate, and a recessed switched test connector oriented within the aperture. The recessed switched test connector includes a test port accessible from a second side of the substrate and a bracket securing the recessed switched test connector within the aperture. 
     In another example printed circuit board according to the presently disclosed technology, the recessed switched test connector protrudes beyond the first side of the substrate. 
     In another example printed circuit board according to the presently disclosed technology, the array of components protrudes beyond the first side of the substrate a magnitude greater than the recessed switched test connector protrudes beyond the first side of the substrate. 
     In another example printed circuit board according to the presently disclosed technology, the recessed switched test connector is set back within the aperture on the second side of the substrate. 
     In another example printed circuit board according to the presently disclosed technology, the recessed switched test connector includes an electrical path through the printed circuit board that is mechanically and electrically disrupted when an associated test probe is inserted into the test port. 
     In another example printed circuit board according to the presently disclosed technology, the electrical path through the printed circuit board is mechanically and electrically restored when the associated test probe is removed from the test port. 
     In another example printed circuit board according to the presently disclosed technology, the test port includes a self-centering countersink for an associated test probe. 
     In another example printed circuit board according to the presently disclosed technology, the second side of the substrate opposes the first side of the substrate. 
     In another example printed circuit board according to the presently disclosed technology, the bracket serves as electrical ground for the recessed switched test connector. 
     In another example printed circuit board according to the presently disclosed technology, the bracket is attached to the second side of the substrate. 
     In another example printed circuit board according to the presently disclosed technology, the recessed switched test connector further comprises a bottom plate crimped to the bracket. An electrical circuit through the recessed switched test connector is compressively secured between the bottom plate and the bracket. 
     An example method of using a recessed switched test connector in a printed circuit board according to the presently disclosed technology includes inserting a test probe into a test port of the recessed switched test connector and certification testing an electrical circuit connected from the recessed switched test connector to the test probe. The recessed switched test connector is oriented within an aperture in a substrate and the recessed switched test connector is accessible from a side of the substrate opposite an array of components attached to the substrate. 
     Another example method of using a recessed switched test connector in a printed circuit board according the presently disclosed technology further includes removing the test probe from the test port of the recessed switched test connector following the certification testing of the electrical circuit. 
     In another example method of using a recessed switched test connector in a printed circuit board according to the presently disclosed technology, inserting the test probe into the test port disrupts an electrical circuit connected through the recessed switched test connector and connects the test probe to the electrical circuit. 
     In another example method of using a recessed switched test connector in a printed circuit board according to the presently disclosed technology, removing the test probe from the test port restores the electrical circuit connected through the recessed switched test connector and disconnects the test probe from the electrical circuit. 
     In another example method of using a recessed switched test connector in a printed circuit board according to the presently disclosed technology, the recessed switched test connector is recessed within the aperture on the side of the substrate opposite the array of printed circuit board components attached to the substrate. 
     In another example method of using a recessed switched test connector in a printed circuit board according to the presently disclosed technology, inserting the test probe into the test port further includes directly grounding the test probe to the recessed switched test connector. 
     An example computing device according to the presently disclosed technology includes a printed circuit board. The printed circuit board includes a substrate including an aperture, an array of components attached to a first side of the substrate, and a recessed switched test connector oriented within the aperture. The recessed switched test connector includes a test port accessible from a second side of the substrate and a bracket securing the recessed switched test connector within the aperture. The computing device also includes a display residing in close proximity to the first side of the substrate and a case residing in close proximity to the second side of the substrate. The case includes a test aperture axially aligned with the test port permitting access to the test port from outside the computing device. 
     Another example computing device according to the presently disclosed technology further includes a test probe for selective insertion into the test port. The test probe is connected to a coaxial cable and an impedance of the test probe substantially matches an impedance of the coaxial cable. 
     Another example computing device according to the presently disclosed technology further includes a test probe for selective insertion into the test port. The test probe is grounded directly to the recessed switched test connector when inserted into the test port. 
     The above specification, examples, and data provide a complete description of the structure and use of exemplary embodiments of the invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended. Furthermore, structural features of the different embodiments may be combined in yet another embodiment without departing from the recited claims.