PATENT DOCUMENT

Publication Number: US-11670435-B2
Application Number: US-202117226491-A
Country: US
Kind Code: B2

Title: Hybrid cabling solution for higher bandwidth and millimeter wave applications

Abstract:
Flexible cables may include multiple power, ground, and signal traces, and include EM interference suppression devices within the cable itself. Signal traces may be shielded by ground traces. The body of a cable may be divided into lateral portions through which different types of traces extend. One lateral side of a cable body may include a stack of power traces, while another lateral side of the cable body may include ground and signal traces. EBG patterns may be incorporated into ground traces. Capacitors may be positioned within the cable along its length, mounted between power and ground traces, for decoupling.

Claims:
What is claimed is: 
     
       1. A flexible cable comprising:
 a flexible body formed of an electrical insulation material, the flexible body including a top, a bottom vertically spaced from the top, with two sides extending vertically between the top and the bottom, the two sides being laterally spaced apart, wherein the flexible body includes first and second longitudinally spaced apart ends; and 
 a plurality of conductive traces extending longitudinally through the flexible body between the first and second ends, wherein the plurality of conductive traces comprises a power trace, a lower ground trace, and a signal trace, such that the signal trace is spaced laterally within the flexible body from the power trace, and the lower ground trace is located vertically beneath both the signal trace and the power trace; 
 wherein the power trace is one of a plurality of power traces stacked vertically within the flexible body; and 
 a first capacitor underneath the lower ground trace, the first capacitor including a first terminal connector connected to the lower ground trace and a second terminal connector connected to the power trace through a via passing through the lower ground trace. 
 
     
     
       2. The flexible cable of  claim 1 , further comprising:
 an interference suppression device within the flexible cable selected from the group consisting of: an EBG grounding pattern formed in the lower ground trace, an LRC circuit formed in the lower ground trace, and a lumped filter formed in the lower ground trace. 
 
     
     
       3. The flexible cable of  claim 1 , further comprising a second capacitor underneath the lower ground trace and connected to the lower ground trace and the power trace, the second capacitor having a different frequency suppression band than the first capacitor. 
     
     
       4. The flexible cable of  claim 1 , further comprising a plurality of additional capacitors underneath the lower ground trace and spaced apart longitudinally along the flexible body between the first and second ends, wherein each additional capacitor of the plurality of additional capacitors includes:
 a first terminal connector connected to the lower ground trace; and 
 a second terminal connector connected to the power trace through a via passing through the lower ground trace. 
 
     
     
       5. The flexible cable of  claim 1 , further comprising an EBG grounding pattern formed in the lower ground trace. 
     
     
       6. The flexible cable of  claim 1 , further comprising a plurality of vertically extending shunt traces interconnecting the plurality of power traces. 
     
     
       7. The flexible cable of  claim 1 , wherein the lower ground trace is one of a plurality of ground traces, and further comprising a plurality of vertically extending shunt traces interconnecting the plurality of ground traces. 
     
     
       8. The flexible cable of  claim 1 , further comprising a middle ground trace, wherein the signal trace is positioned vertically between the middle ground trace and the lower ground trace. 
     
     
       9. The flexible cable of  claim 1 , further comprising a middle ground trace, an upper ground trace, and a second signal trace, wherein the signal trace is a first signal trace, the first signal trace being positioned vertically between the lower ground trace and the middle ground trace, and the second signal trace being positioned vertically between the middle ground trace and the upper ground trace. 
     
     
       10. The flexible cable of  claim 9 , further comprising a third signal trace and a fourth signal trace, the third signal trace being positioned vertically between the lower and middle ground traces and laterally adjacent to the first signal trace, and the fourth signal trace being positioned vertically between the middle and upper ground traces and laterally adjacent to the second signal trace. 
     
     
       11. The flexible cable of  claim 9 , further comprising an interference suppression trench extending vertically between the top and the bottom of the flexible body laterally adjacent to the first signal trace. 
     
     
       12. The flexible cable of  claim 1 , further comprising a middle ground trace, wherein the power trace is positioned vertically between the lower ground trace and the middle ground trace. 
     
     
       13. The flexible cable of  claim 1 , further comprising a junction block between the first and second ends and a second signal trace, and wherein:
 the signal trace is a first signal trace, 
 the flexible body splits into first and second arms at the junction block, 
 the first signal trace extends from the junction block only through the first arm; and 
 the second signal trace extends from the junction block only through the second arm. 
 
     
     
       14. The flexible cable of  claim 13 , wherein the junction block further comprises a switch, an interference suppressor, signal enhancement circuitry, or combinations thereof. 
     
     
       15. A system comprising:
 a first radio frequency transceiver, a second radio frequency transceiver, and a power source; and 
 a cable comprising a flexible body formed of an electrical insulation material, the flexible body including a top, a bottom vertically spaced from the top, with two sides extending vertically between the top and the bottom, the two sides being laterally spaced apart, wherein the flexible body includes first and second longitudinally spaced apart ends; 
 a plurality of conductive traces extending longitudinally through the flexible body between the first and second ends, wherein the plurality of conductive traces comprises a power trace, a lower ground trace, and a signal trace, such that the signal trace is spaced laterally within the flexible body from the power trace, and the lower ground trace is located vertically beneath both the signal trace and the power trace; 
 wherein the power trace is one of a plurality of power traces stacked vertically within the flexible body; 
 a first capacitor underneath the lower ground trace, the first capacitor including a first terminal connector connected to the lower ground trace and a second terminal connector connected to the power trace through a via passing through the lower ground trace; and 
 wherein the power trace is connected to the power source and the signal trace is connected to both of the first and second radio frequency transmitters to communicate a signal therebetween.

Description:
BACKGROUND 
     Field 
     Embodiments described herein relate to cabling useful for the transmission of power and signals, and more particularly to such cabling used in electronic devices. 
     BACKGROUND INFORMATION 
     In electronic devices that include radio wave transceivers, for example mobile phones, tablets, phablets, laptop computers, and numerous other devices, a carrier wave of a digital signal is often shifted from a first transmission frequency to an intermediate frequency (IF) for transmission within the device, before being again shifted to the transmission frequency from an antenna. Currently, board-to-board connections between IF transceivers that sit on a main board and an antenna, for example a side-firing millimeter wave antenna-in-package (AIP) array, are limited due to isolation, IR drop, voltage droop, and size with respect to area and cost. 
     Electromagnetic Band Gap (EBG) structures are structures that generate a stopband which greatly inhibits or completely blocks electromagnetic waves of predefined frequency bands. Some EBGs include a small, periodic pattern of small metal areas or patches on a dielectric substrate. EBG can refer to both the blocked frequency band as well as a device or medium itself which transmits electromagnetic waves that includes such a structure. EBG structures have been used with components of electronic devices to suppress electromagnetic noise. Because an EBG structure reflects only a small portion of electromagnetic waves of the frequency bands it can detect, the EBG shows high sensitivity in its receiving frequencies. 
     SUMMARY 
     Flexible cables are described in which power, signal, and ground traces may be laterally and vertically separated. 
     In an embodiment, a flexible cable includes a flexible body formed of an electrical insulation material and may include a top, a bottom vertically spaced from the top, and two sides extending vertically between the top and the bottom. The two sides may be laterally spaced apart, and the flexible body may include first and second longitudinally spaced apart ends. A plurality of conductive traces may extend longitudinally through the flexible body between the first and second ends. The plurality of conductive traces may include at least one power trace, at least one ground trace, and at least one signal trace, such that at least one signal trace is spaced laterally within the body from the at least one power trace. 
     In some embodiments, a flexible cable may include at least one interference suppression device within the flexible cable, which may be an embedded capacitor, an EBG grounding pattern formed in the at least one ground trace, a trench extending vertically between the top and the bottom, an LRC circuit formed in the at least one ground trace, or a lumped filter formed in the at least one ground trace. 
     In some embodiments, the at least one interference suppression device includes two interference suppression devices having different frequency suppression bands. The at least one interference suppression device may include at least one capacitor in electrical communication between the at least one power trace and the at least one ground trace. The at least one ground trace may be positioned vertically between the at least one capacitor and the at least one signal trace. 
     In some embodiments, the at least one interference suppression device may include at least one capacitor in electrical communication between the at least one power trace and the at least one ground trace. The at least one interference suppression device may include an EBG grounding pattern formed in the at least one ground trace. The at least one power trace may include a plurality of power traces stacked vertically within the body and laterally spaced from the at least one signal trace. 
     In some embodiments, a flexible cable may also include a plurality of vertically extending shunt traces interconnecting the plurality of power traces. A flexible cable may also include a plurality of vertically extending shunt traces interconnecting the plurality of ground traces. The at least one power trace may be laterally spaced from the at least one ground trace and from the at least one signal trace. The at least one signal trace may be vertically spaced from the at least one ground trace. The at least one ground trace may include two ground traces, and the at least one signal trace may be positioned vertically between the two ground traces. 
     In some embodiments, the at least one ground trace may include first, second, and third ground traces, and the at least one signal trace may include first and second signal traces, with the first signal trace being positioned vertically between the first and second ground traces, and the second signal trace being positioned vertically between the second and third ground traces. The at least one signal trace may also include third and fourth signal traces, with the third signal trace being positioned vertically between the first and second ground traces and laterally adjacent to the first signal trace, and the fourth signal trace being positioned vertically between the second and third ground traces and laterally adjacent to the second signal trace. A flexible cable may also include an interference suppression trench extending vertically between the top and the bottom laterally adjacent to the at least one signal trace. 
     In some embodiments, the at least one ground trace may include two ground traces and the at least one power trace may be positioned vertically between the two ground traces. 
     In some embodiments, a flexible cable may also include a junction block between the first and second ends, the at least one signal trace may include first and second signal traces, the body splits into first and second arms at said junction block, the first signal trace extends from the junction block only through the first arm, and the second signal trace extends from the junction block only through the second arm. The junction block may also include at least one switch, at least one interference suppressor, signal enhancement circuitry, or combinations thereof. 
     In an embodiment, a system may include a first radio frequency transceiver, a second radio frequency transceiver, and a power source. A cable may include a flexible body formed of an electrical insulation material, the flexible body including a top, a bottom vertically spaced from the top, and two sides extending vertically between the top and the bottom, with the two sides being laterally spaced apart. The flexible body may include first and second longitudinally spaced apart ends. A plurality of conductive traces may extend longitudinally through the flexible body between the first and second ends. The plurality of conductive traces may include at least one power trace, at least one ground trace, and at least one signal trace, such that at least one signal trace is spaced laterally within the body from the at least one power trace. The at least one power trace may be connected to the power source and the at least one signal trace may be connected to both of the first and second radio frequency transmitters to communicate a signal therebetween. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    illustrates a highly simplified plan view of a flexible cable; 
         FIG.  2    illustrates a cross sectional view taken at line A-A in  FIG.  1   ; 
         FIG.  3    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a first embodiment of a cable; 
         FIG.  4    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a second embodiment of a cable; 
         FIG.  5    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a third embodiment of a cable; 
         FIG.  6    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a fourth embodiment of a cable; 
         FIG.  7    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a fifth embodiment of a cable; 
         FIG.  8    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a sixth embodiment of a cable; 
         FIG.  9    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a seventh embodiment of a cable; 
         FIG.  10    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of an eighth embodiment of a cable; 
         FIG.  11    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a ninth embodiment of a cable; 
         FIG.  12    illustrates a highly simplified plan view of a ground trace; 
         FIG.  13    illustrates a cross-sectional view taken at line B-B in  FIG.  5   ; 
         FIG.  14    illustrates a flexible cable including two arms; 
         FIG.  15   . illustrates an example mobile phone including a flex cable; 
         FIG.  16    illustrates an example tablet including a flex cable; and 
         FIG.  17    illustrates an example laptop computer including a flex cable. 
     
    
    
     DETAILED DESCRIPTION 
     Described herein are exemplary embodiments of flex cables. In various embodiments, description is made with reference to figures. However, certain embodiments may be practiced without one or more of these specific details, or in combination with other known methods and configurations. In the following description, numerous specific details are set forth, such as specific configurations, dimensions, and processes, etc., in order to provide a thorough understanding of the embodiments. In other instances, well-known manufacturing techniques have not been described in particular detail in order to not unnecessarily obscure the embodiments. Reference throughout this specification to “one embodiment” means that a particular feature, structure, configuration, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrase “in one embodiment” in various places throughout this specification are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, configurations, or characteristics may be combined in any suitable manner in one or more embodiments. 
     The terms “above”, “over”, “to”, “between”, “in”, and “on” as used herein may refer to a relative position of one element with respect to other elements. One element “above” or “over” another element may be directly in contact with the other element or may have one or more intervening elements. One element “between” other elements may be directly in contact with the elements or may have one or more intervening elements. 
     In one aspect, embodiments may include constructions of flexible cables, which may be intermediate frequency cables, which may include power traces, interference suppression or cancellation filters, and/or repeated placement of capacitors, in space constrained applications. Laterally separating power traces from signal traces within the body of a flexible cable may also improve signal transmission fidelity. 
     Referring now to  FIG.  1   , a highly simplified top plan view of a flex cable  100  is illustrated. Cable  100  may be connected between two or more electronic components  102 ,  104 , which may be, but are not limited to, radio frequency transceivers, e.g., IF transceivers operating within 9-15 Ghz, which may be or include frequency down converters, and the like, and other electronic components as described elsewhere herein which are connected to any other electrical component by an electrical conductor in order to perform its function. Such radio frequency transceivers are well known, commonly commercially available, and are incorporated into many electronic devices, including mobile phones. Components  102 ,  104  may also include voltage sources, e.g., VDD, connections to electrical ground, antennae, and the like. The components  102 ,  104  are located at opposite longitudinal ends of the flex cable  100 . Elements (e.g., components  102 ,  104 ) connected to the ends of flex cable  100  and other flex cables as described herein, may include electronic modules, multi-layer boards (MLBs), systems-in-package (SiPs), antenna modules, or other hardware with circuitry configured to transmit and/or receive signals over flex cables. 
       FIG.  2    illustrates a cross sectional view of a flex cable, such as flex cable  100 , taken at line A-A in  FIG.  1   . The flex cable  100  includes a body  112  formed of an electrically insulating material, e.g., a dielectric material, which is flexible enough to bend back on itself without breaking or rupturing. An optional casing  110  may be provided on the outer surface of the body  112 . The body  112  includes a top  126 , a bottom  128 , and sides  130 ,  132  extending between the top and the bottom. In embodiments, the cross-section of the body  112  may be rectangular, i.e., the top and bottom are longer than each of the sides. For the sake of clarity, the illustrations herein may exaggerate the vertical thickness of the body  112 . As used herein, the word “vertical” (or its equivalent) means the direction directly between the top and bottom, and the word “lateral” (or its equivalent) means the direction directly between the two sides, perpendicular to “vertical.” The designations top, bottom, and side(s) may be arbitrary, as a flex cable may be rotated in space without changing its structure, and therefore these terms are used merely to assist in describing the cables described herein. 
     Encased within the material of the body  112  are a plurality of electrical conductors which extend longitudinally along the flex cable  100  between its two opposite ends at components  102 ,  104 . The conductors may take any of numerous forms, including but not limited to electrically conductive wires, electrically conductive ink, differential lines, transmission lines, or wide buses, any of which are generally referred to herein as a “trace”. The plurality of traces may include one or more power traces, ground traces, and signal carrying traces, as well as other traces performing different functions. In some embodiments a respective trace is electrically and/or physically continuously connected between component  102  and component  104 . In some embodiments a respective trace is electrically and/or physically continuously connected between component  102  and component  104 , through an intermediate structure embedded in flex cable  100 , such as a repeater. In some embodiments a respective trace is not electrically and/or physically continuously connected between component  102  and component  104 . For example, such a structure may be embedded within casing  110  for shielding purposes and/or to provide mechanical support. The plurality of traces may include ground traces  114 ,  116 ,  118 , which extend laterally (left and right in  FIG.  2   ) through the body  112  nearly completely between the sides  130 ,  132 , leaving a small portion of the body laterally enveloping the traces so that they are electrically insulated. The plurality of traces may further include a power trace  120 , e.g., a VDD, a base supply voltage for microelectronics. Power trace  120  may be vertically positioned (“sandwiched”) between two of the ground traces, e.g., ground traces  116  and  118 , which isolates the power being transmitted through the flex cable. The plurality of traces may further include one or more signal traces, e.g., intermediate frequency signal traces  122 ,  124 , which may be vertically sandwiched between ground traces  114 ,  116  and laterally spaced from each other in laterally left and right portions of the cross-section of the body  112 . In this manner, the power trace  120  is isolated from the signal traces  122 ,  124  by the interposition of a ground trace  116 . Such a configuration may, however, experience noisy signals transmitted along the signal traces because there is no provision for noise cancellation or filtering along the cable itself, and has limited power transmission capacity because of the inclusion of only a single power trace. In some embodiments, cables described herein may be a flexible flat cable (FFC), a ribbon cable, a flexible printed circuit (FPC), a coaxial cable, or any other type of cable. Furthermore, flexible materials may be used to form cables described herein, such as liquid crystal polymer (LCP) and polyimide and may be mixed or otherwise combined with very high permittivity materials so that the resulting composite material may act as distributed capacitance along the length of a flex cable, which may also reduce EM interference. By way of example and not of limitation, alumina, ceramic powders, nano composites, and the like may be used to produce a high permittivity flex cable, which may benefit noise reduction on power traces and may reduce voltage droop. Additionally, the use of such a composite material may also make EBGs more effective. 
       FIG.  3    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a first embodiment of a flex cable  200 . Cable  200  includes a body  204  formed of an electrically insulating material, e.g., a dielectric, which may optionally be enveloped in an outer casing  202 . The body  204  includes a top  234 , a bottom  236 , and two sides  238 ,  240  extending between the top and the bottom. Cable  200  may include an upper ground trace  206  adjacent the top  234 , a lower ground trace  210  adjacent to the bottom  236 , and a middle ground trace  208  positioned vertically between the upper and lower ground traces and may form gaps between it and each of the upper and lower ground traces. Ground traces  206 ,  210  may extend laterally through the body  204  nearly completely between the sides  238 ,  240 , leaving a small portion of the body laterally enveloping the ground traces so that they are electrically insulated. Middle ground trace  208  is laterally shorter than one or both of the upper ground trace  206  and the lower ground trace  210  and is laterally positioned on one lateral portion (here, the right portion in  FIG.  3   ) within the body  204 , its end adjacent to the side  238  insulated by a small portion of the body. 
     A number of signal traces may longitudinally extend through the body  204 . By way of example, signal traces  218 ,  220  may be located between the upper ground trace  206  and the middle ground trace  208 , in the gap formed therebetween, and may be generally vertically aligned with the middle ground trace. Signal traces  222 ,  224  may be located between the lower ground trace  210  and the middle ground trace  208 , in the gap formed therebetween, and may also be generally vertically aligned with the middle ground trace. In this way, one lateral portion of the body houses the signal traces  218 - 224 , vertically sandwiched between ground traces to provide shielding and mechanical stability. Each of the signal traces  218 - 224  may be attached to the same or different signal sources, e.g., a first intermediate frequency generator, a second intermediate frequency generator, an intermediate frequency clock, or one or more control signals. 
     The cable  200  may include a number of power traces longitudinally extending through the body  204 . In some embodiments, power traces  212 ,  214 ,  216  are vertically spaced apart from each other, are stacked and vertically sandwiched between upper ground trace  206  and lower ground trace  210  without contacting either ground trace and are located laterally next to the signal traces  218 - 224  and the middle ground trace  208  on one lateral portion of the body  204 . In some embodiments, the power traces may be grouped together as a set  242  of a plurality of power traces, indicated throughout by broken line, which permits power traces to be arranged without a signal trace or ground trace between any of the power traces. In some embodiments, the plurality of power traces in a set  242  may carry more than one voltage through the cable because of the provision of more than one conductor. Additionally, a set of a plurality of power traces may be laterally sized and positioned so as to not span the entire width of the cable, which may leave lateral space for signal and/or ground traces laterally adjacent to one ore a plurality of power traces in a set of power traces. The power traces  212 - 216  may be connected to the same voltage source. In some embodiments, each respective power trace (e.g., of power traces  212 - 216 ) in flex cable  200  may be connected to one of a plurality of voltage sources. The laterally middle ends of each of the power traces  212 - 216  are spaced and electrically insulated from the signal traces  218 - 224  and the middle ground trace  208 . One of ordinary skill in the art will appreciate that the number of signal traces, power traces, and ground traces in flex cable  200  may vary from those depicted in  FIG.  3   . In some embodiments, power traces, including but not limited to power traces  212 - 216 , may be directly laterally adjacent to signal traces, e.g., including but not limited to signal traces  218 - 224 . 
     One or more interference suppression devices may be included in the body  204  to suppress EM interference and coupling from the power traces. In some embodiments, the interference suppression devices may be one or more capacitors  226  positioned within the body  204 . In the embodiment of  FIG.  3   , capacitor(s)  226  are positioned between the lower ground trace  210  and the bottom  236  of the body  204 . A first terminal connector  228  for each capacitor electrically connects the capacitor  226  to power trace  216  through an insulated via  232  or the like which passes through the lower ground trace  210 , while a second terminal connector  230  for each capacitor electrically connects the capacitor to the lower ground trace. As well understood by those of ordinary skill in the art, embedded passive elements in flex cable  200 , such as capacitor(s)  226 , may decouple the power from the signals transmitted through the signal traces. Capacitor(s)  226  may be multilayer ceramic chip capacitors, e.g.,  0402  and/or  0201  capacitors, liquid crystal polymer capacitors, or the like, and may be shielded. 
       FIG.  4    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a second embodiment of a flex cable  250 . Flex cable  250  is very similar to flex cable  200 , and therefore only their differences will be described. In some embodiments, passive elements such as capacitor(s)  226 , are embedded with the power traces so that the via  232  can be eliminated. Capacitor(s)  226  are positioned to overlap part of one of the power traces and part of one of the ground traces so that terminal connector  228  is in contact with the power trace  216  and terminal connector  230  is in contact with middle ground trace  208 . 
       FIG.  5    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a third embodiment of a flex cable  300 . As with other embodiments described herein, cable  300  includes ground traces  206 ,  208 ,  210  and signal traces  218 - 224  segregated to one lateral portion (in  FIG.  5   , the right portion) of the cable body. Ground traces  206  and  210  are laterally the same length as ground trace  208 , so that one lateral portion of the interior of the cable body includes a vertical, alternating stack of ground traces and signal traces. The laterally opposite portion of the cable body includes a vertical stack of spaced apart power traces  216 . In some embodiments, all of power traces  216  may be connected to the same voltage source, and in some embodiments each respective power trace  216  is connected to one of a plurality of voltage sources. One of ordinary skill in the art will recognize that while five traces are illustrated, the cable  300  may include more or fewer. Capacitor(s)  226  are positioned generally laterally centered, vertically between the lower ground trace  210  and the bottom  236  of the body  204 , and vertically between the lowermost power ground trace  216  and the bottom of the body. A first terminal connector  228  for each capacitor electrically connects the capacitor  226  to the lowermost power trace  216 , while a second terminal connector  230  for each capacitor electrically connects the capacitor to the lower ground trace  210 . In some embodiments, power traces, including but not limited to power traces  216 , may be directly laterally adjacent to signal traces, e.g., including but not limited to signal traces  218 - 224 . 
       FIG.  6    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a fourth embodiment of a flex cable  350 . Flex cable  350  is very similar to flex cable  300 , and therefore only their differences will be described. Cable  350  includes one or more interconnecting shunt traces  352 ,  354  which electrically interconnect the several power traces  216  and the ground traces  206 - 210 , respectively. Shunt traces  352 ,  354  extend vertically between and/or through individual traces and may have a longitudinal length (in and out of the plane of  FIG.  6   ) about the same as their lateral width. The longitudinal length of the shunt traces  352 ,  354  may stiffen the cable  350  against flexing up-and-down (i.e., with a neutral plane extending laterally and out of the plane of  FIG.  6   ). In some embodiments, shunt traces may be implemented in portions of flex cable  350 , and therefore can be selected to stiffen some longitudinal sections of the cable  350 , while leaving other longitudinal sections with essentially the same flexibility as cable  300  of  FIG.  5   . 
       FIG.  7    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a fifth embodiment of a flex cable  400 . As with the description of  FIG.  6   , flex cable  400  is very similar to flex cables  300 ,  350  and therefore only their differences will be described. Cable  400  includes ground traces  402 ,  404 ,  406  in the place of ground traces  206 ,  208 ,  210 . Ground traces  402 ,  404 ,  406  may each include one or more EM interference suppression devices. The one or more EM interference suppression devices may be any known devices that may be physically incorporated into the flex cable  400 , including, but not limited to, an EBG grounding pattern formed in, and/or serially in line with, one or more of the ground traces  402 ,  404 ,  406 , and/or an LRC circuit formed in, and/or serially in line with, one or more of the ground traces, and/or lumped filters formed in, and/or serially in line with, one or more of the power and/or ground traces. When more than one EM interference suppression devices are incorporated into one or more of the ground traces, they may be designed or tuned to suppress EM interference in the same frequency band, overlapping frequency bands, or non-overlapping frequency bands, depending on the nature of the EM interference to which cable  400  is exposed. In this manner, EM interference in noisy environments in which the cable  400  is to be used can be selectively attenuated from interfering with the signals carried on the one or more signal traces  218 - 224 . 
       FIG.  8    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a sixth embodiment of a flex cable  450 . Flex cable  450  has a basic arrangement or configuration of its traces that differs in some respects from those of other embodiments described herein but retains some similarities as well. In one sense, cable  450  may be thought of as cable  300  ( FIG.  5   ) with the ground and signal traces laterally moved from a first lateral portion (e.g., the right lateral portion, as viewed in  FIG.  8   ) of the cable  300  to a center portion of cable  450 , the power traces reduced in lateral length, and a second set of power traces added to the first lateral portion (e.g., the right lateral portion) of the cable  450 . Thus, cable  450  may include a first set of power traces  452  positioned laterally in a second lateral portion (e.g., left lateral portion, as viewed in  FIG.  8   ) of the cable. When more than one trace  452  is provided, they may be stacked vertically, as described elsewhere herein. Cable  450  may include a second set of power traces  454  positioned laterally in a right lateral portion of the cable; and, when more than one trace  454  is provided, they likewise may be stacked vertically, as described elsewhere herein. A laterally center portion of the cable  450  may include ground traces  206 ,  208 ,  210 , and signal traces  218 - 224 , as described elsewhere herein. Power traces  452 ,  454  may be connected to the same or to different voltage sources, and the same or different electronic components  102 ,  104 . When connected to different voltage sources, power traces  452 ,  454  may be connected to different electronic components which have different power requirements. Cable  450  may also include one or more capacitors  456 ,  458 , which may be substantially similar to capacitors described elsewhere herein. Capacitors  456 ,  458  may include first and second terminal connector  228 ,  230 , as described elsewhere herein, and are positioned to electrically connect each set of power traces  452 ,  454  to a ground trace, e.g., ground trace  210 . In the illustrated embodiment, capacitors  456 ,  458  span the left and center, and right and center, lateral portions of the cable.  FIG.  8    also includes directional arrow A, to which reference will be made elsewhere herein. In some embodiments, power traces, including but not limited to power traces  452 ,  454 , may be directly laterally adjacent to signal traces, e.g., including but not limited to signal traces  218 - 224 . 
       FIG.  9    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of a seventh embodiment of a flex cable  550 . Cable  500  may include a plurality of ground traces  502 ,  504 ,  508 ,  510 , and  512 , one or more power traces  506 , signal traces  218 - 224  as described elsewhere herein, and shielding trenches  514 ,  516 . In a first lateral portion (here the left lateral portion) of the body  204  of the cable  500 , a vertical sandwich or stack is formed of ground trace  502  vertically adjacent to the top of the body  204 , ground trace  504  vertically adjacent to the bottom of the body, and one or more power traces  506  vertically stacked between the ground traces  502 ,  504 . In a second lateral portion (here the right lateral portion) of the body  204  of the cable  500 , ground traces  508 ,  510 ,  512 , and signal traces  218 - 224  may be arranged in a vertical double-decker sandwich configuration as described elsewhere herein, e.g., with respect to  FIG.  5   . In some embodiments, a first vertically and longitudinally extending trench  514  may be positioned between the right-side lateral ends of the traces  502 - 506  and the left side lateral ends of traces  218 - 224  and  508 - 512 ; that is, trench  514  may be positioned approximately in the lateral middle of the body  204 . In some embodiments, a trench, such as trench  514 , is positioned within cable  500  equidistantly between a set of power traces (e.g., power traces  506 ) and a set of signal traces (e.g., signal traces  218 - 224 ). In some embodiments, second vertically and longitudinally extending trench  516  may be positioned on the far-right lateral portion of the body  204 , to the right of the right side ends of traces  218 - 224  and  508 - 512 . In some embodiments, a trench may be positioned between signal traces of a set of signal traces, to mitigate cross-talk between signal traces. Trenches  514 ,  516  are provided to shield the signal traces  218 - 224 , the ground traces  508 - 512 , or both from EM interference which may originate from power traces  506  and from sources external to the body  204 . Trenches  514 ,  516  may be formed of any material(s) suitable for this purpose, including, but not limited to, copper and the like. In this manner, signal traces  218 - 224  are shielded vertically by ground traces, and laterally by one or more trenches  514 ,  516 . In some embodiments, one or more trenches, such as trenches  514 ,  516  may continuously extend the entire longitudinal length of cable  500 , and in some embodiments the one or more trenches may extend discontinuously for some or all of the entire longitudinal length of cable  500 . In some embodiments, one trench (e.g., trench  514 ) may extend continuously for the entire longitudinal length of cable  500 , while another trench (e.g., trench  516 ) does not extend continuously for the entire longitudinal length of cable  500 . In some embodiments, power traces, including but not limited to power traces  506 , may be directly laterally adjacent to signal traces, e.g., including but not limited to signal traces  218 - 224 , separated by trench  514 . 
       FIG.  10    illustrates a cross sectional view, similar to that taken at line A-A in  FIG.  1   , of an eighth embodiment of a flex cable  550 . Cable  550  is similar in many respects to cable  200  described with respect to  FIG.  3   . Cable  550  embodies and is an example of the further inclusion of EM interference suppression devices into one or more of any power and/or ground trace in any flex cable, including, but not limited to, those described expressly herein. As with the cable  200 , cable  550  may include signal traces  218 - 224 , arranged as described with reference to  FIG.  3   . Cable  550  also may include power and ground traces as arranged in cable  200 ; however, one or more of the power and/or ground traces exemplified in cable  550  may include one or more EM interference suppression devices. Thus, one or more of power traces  558 ,  560 ,  562  may include one or more EM interference suppression devices, and one or more of ground traces  552 ,  554 ,  556  may include one or more EM interference suppression devices. The one or more EM interference suppression devices may be any known devices that may be physically incorporated into the flex cable  550 , including, but not limited to, an EBG grounding pattern formed in, and/or serially in line with, one or more of the power and/or ground traces, and/or an LRC circuit formed in, and/or serially in line with, one or more of the power and/or ground traces, and/or lumped filters formed in, and/or serially in line with, one or more of the power and/or ground traces. When more than one EM interference suppression devices are incorporated into one or more of the power and/or ground traces, they may be designed or tuned to suppress EM interference in the same frequency band, overlapping frequency bands, or non-overlapping frequency bands, depending on the nature of the EM interference to which the cable is exposed, which may be any flex cable described herein. In this manner, EM interference in noisy environments in which the cable is to be used can be selectively attenuated from interfering with the signals carried on the one or more signal traces  218 - 224 . In some embodiments, power traces, including but not limited to power traces  558 - 562 , may be directly laterally adjacent to signal traces, e.g., including but not limited to signal traces  218 - 224 . In some embodiments, each power trace may have a dedicated EM interference suppression device, e.g., a capacitor between each power trace and a ground trace. 
       FIG.  11    illustrates a cross sectional view, similar to that taken at line A-A in FIG.  1 , of a ninth embodiment of a flex cable  600 . In general terms, cable  600  may have a left-right laterally symmetric arrangement of power, ground, and signal traces, with a trench positioned in a middle portion of the body of the cable to shield the traces of each side from the traces of the other side. Stated somewhat differently, the left and right lateral portions of cable  600  may be mirror images of each other. Cable  600  may include one or more first power traces  452  positioned laterally in first portion (here a left lateral portion) of the body  204 ; when more than one power trace  452  is provided, they may be vertically arranged in a stack, and may be connected to the same or different voltage sources. Cable  600  may include one or more second power traces  454  positioned laterally in second portion (here a right portion) of the body  204 ; when more than one power trace  454  is provided, they may be vertically arranged in a stack, and may be connected to the same or different voltage sources. In embodiments, power traces  452  are connected to different voltage sources and different components  104  from power traces  454 . By way of a non-limiting example, power traces  452  may be connected to VDD main, and power traces  454  may be connected to VDD aux. 
     Cable  600  may include one or more ground traces  602 ,  604 ,  606 , vertically stacked to one lateral side (here the right side) of the power traces  452 , and one or more ground traces  608 ,  610 ,  612 , vertically stacked to the other lateral side (the left side) of the power traces  454 . One or more signal traces  614 ,  616 ,  618 ,  620  may be positioned between ground traces  602 ,  604 ,  606 , for example, with signal traces  614 ,  616  positioned laterally adjacent to each other and vertically sandwiched between ground traces  602 ,  604 , and signal traces  618 ,  620  positioned laterally adjacent to each other and vertically sandwiched between ground traces  604 ,  606 . Likewise, one or more signal traces  622 ,  624 ,  626 ,  628  may be positioned between ground traces  608 ,  610 ,  612 , for example, with signal traces  622 ,  624  positioned laterally adjacent to each other and vertically sandwiched between ground traces  608 ,  610 , signal traces  626 ,  628  positioned laterally adjacent to each other and vertically sandwiched between ground traces  610 ,  612 . Each of the signal traces  614 - 628  may carry the same or a different signal from the other signal traces. One or more trench(es)  630  may be positioned between the right (middle) ends of ground traces  602 ,  604 ,  606  and the left (middle) ends of ground traces  608 ,  610 ,  612 . Trench  630  may be substantially the same in construction as trenches  514 ,  516  as discussed elsewhere herein. In embodiments, the power and signal traces from one lateral portion (here the right lateral portion) of cable  600  lead to and from a first set of transceivers, and the power and signal traces from the other lateral portion (here the left lateral portion) of cable  600  lead to and from a second set of transceivers, different from the first set of transceivers. Cable  600  may be useful when left-right symmetry may be useful, e.g., in virtual or augmented reality headsets to segregate the left and right image data signals. In some embodiments, power traces, including but not limited to power traces  452 ,  454 , may be directly laterally adjacent to signal traces, e.g., including but not limited to signal traces  614 - 628 , separated by trench  630 . 
       FIG.  12    illustrates a highly simplified plan view of a power trace  558  or ground trace  552 , as seen in the direction of arrow A in  FIG.  8   , which includes one or more EM interference suppression devices  640 , such as any of those described elsewhere herein, positioned along the longitudinal length of the trace. 
     The EM interference suppression devices  640  may include an EBG pattern formed in, and/or serially in line with, one or more of the power and ground traces  558 ,  552 , and/or an LRC circuit formed in, and/or serially in line with, one or more of the power and ground traces, and/or lumped filters formed in, and/or serially in line with, one or more of the power and/or ground traces. Forming such EM interference suppression devices in the trace itself, or serially along the trace, may greatly decrease the volume needed to provide the EM interference suppression devices and may benefit from being formed when the traces are formed within the body  204 . 
       FIG.  13    illustrates a cross-sectional view taken at line B-B in  FIG.  5    and illustrates the longitudinally extending power traces  216  within the body  204  of the cable  300 . The dotted lines on the left and right of the figure indicate that the cable  300  continues longitudinally in both directions. Capacitors  226  are spaced apart from each other longitudinally, under and in electrical contact with the bottommost power trace  216 . 
       FIG.  14    illustrates a flexible cable  650  which may include two arms which branch out from a portion of the cable between its two longitudinal ends. Cable  650  may take the form of any cable described herein. Cable  650  may include a first section  652  which leads from a first electronic component  658 , which may include sources of power, ground, and signals to be transmitted. The first section  652  may be exposed to, e.g., be routed next to, one or more noisy electronic components  654 ,  656 , the EM interference from which may disrupt signals being transmitted. By forming cable  650  at least in part as one of the cables described herein, the EM interference from the components  654 ,  656  can be attenuated and/or suppressed, and the signals transmitted through the cable can have higher signal-to-noise ratios. 
     Cable  650  may include a junction block  660  located along the length of the cable. Junction block  660  may include one or more switches, capacitors, repeaters, amplifiers, and the like, which facilitate the further transmission of signals along the cable  650 , which may include splitting cable  650  into two arms  664 ,  670 . In some embodiments, arm  664  leads to an electronic component  662 , e.g., a transceiver, and arm  670  leads to an electronic component  668 , e.g., a transceiver different from transceiver  662 . When cable  650  is constructed as one of the cables described herein, each of the two arms  664 ,  670  may include power and signal traces only for the electronic component  662 ,  668 , respectively. For example, the first section  652  of the cable  650  may act as a power and signal superhighway for multiple downstream electronic components, while arms  664 ,  670  act as local roadways for the power and signals destined for specified components  662 ,  668 . 
     In some embodiments, junction block  660  may include signal enhancement circuitry for one or more downstream receiving components (e.g., components  662  and  668 ). This signal enhancement circuitry may include one or more repeaters to receive one or more signals from a signal trace in first section  652 , and transmit regenerated versions of the one or more signals on a respective arm (e.g., arm  664  or  670 ). In some embodiments junction block  660  includes circuitry to identify the intended destination for one or more signals received from first section  652  of cable  650 , and to direct the one or more signals to the identified destination. Signal enhancement circuitry in junction block  660  may include signal amplification circuitry to amplify a received signal from first section  652 , before transmitting it to a destination (e.g., component  662 ). In some embodiments, junction block  660  merely provides a physical junction to split one or more traces within first section  652  of cable  650 , onto a respective arm (e.g., arm  664  or arm  670 ). In some embodiments, cable  650  does not split after junction block  660  and continues to a single destination component. 
     In some embodiments, voltage regulators and/or DC-to-DC active circuits may also be placed in series in one or more of the power traces described herein to limit noise and step up or step down voltages. Furthermore, additionally high power switches may be added in one or more of the power traces described herein to manipulate voltage levels and direct voltage to desired locations. 
       FIG.  15   . illustrates an example mobile phone  700  including any of the flex cables described herein. The mobile phone  700  may include a housing  702  in which a radio transceiver, generally indicated at  704 , is contained, and a flex cable, generally indicated at  706 , extending through the housing to the radio transceiver. 
       FIG.  16    illustrates an example tablet  720  including any of the flex cables described herein. The tablet  720  may include a housing  722  in which a radio transceiver, generally indicated at  724 , is contained, and a flex cable, generally indicated at  726 , extending through the housing to the radio transceiver. 
       FIG.  17    illustrates an example laptop computer  740  including any of the flex cables described herein. The laptop  740  may include a housing  742  in which a radio transceiver, generally indicated at  746 , is contained, and a flex cable, generally indicated at  744 , extending through the housing to the radio transceiver. 
     In utilizing the various aspects of the embodiments, it would become apparent to one skilled in the art that combinations or variations of the above embodiments are possible for forming flexible cables including laterally and/or vertically segregated power, ground, and signal traces. Although the embodiments have been described in language specific to structural features and/or methodological acts, it is to be understood that the appended claims are not necessarily limited to the specific features or acts described. The specific features and acts disclosed are instead to be understood as embodiments of the claims useful for illustration.

Metadata:
Filing Date: 20210409
Publication Date: 20230606
Grant Date: 20230606
Priority Date: 20210409
Inventors: DALMIA, Sidharth S.
DHALIWAL, Kiranjit
Assignee: APPLE INC
CPC Classifications: [{"code": "H01B11/18", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01B7/0823", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01B9/003", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01B7/0861", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01B7/04", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01B7/04", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01B11/18", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01B9/003", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01B7/04", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 83510953