Patent Application
20140187087
The subject matter herein relates generally to radio frequency (RF) cable connectors.
Conventional cable connectors for use in handheld devices have small sizes to fit within the small space of the handheld device. Some known cable connectors are referred to as micro-coax assemblies, which use coaxial cables with small connectors for mating to a circuit board or other component within the device. The micro-coax assemblies use paddle cards that mate with card edge connectors on the circuit board. The coaxial cables are terminated to the paddle cards using a soldered connection, where the signal conductor is soldered to a signal pad on the paddle card and the outer shield of the coaxial cable is soldered to a ground pad or ground bar. The paddle card transitions the signals using traces to a mating edge of the paddle card, which is plugged into the card edge connector.
Using the paddle card and card edge connector adds cost and bulk to the system taking up valuable space in the device. Soldering each of the signal conductors and outer shield adds cost and complexity to the manufacture of the cable connector. Additionally, soldering of the signal conductors reduces the electrical performance of the signal conductors by affecting the impedance along the signal path.
A need remains for a reliable and cost effective cable connector.
In one embodiment, an RF cable connector is provided including a cable assembly having a plurality of RF cables bundled together and a buss bar coupled to the cable assembly. Each RF cable has a pair of signal conductors surrounded by an outer shield. The cable assembly has signal contacts terminated to ends of the signal conductors configured to be terminated to corresponding signal pads of a host circuit board. The buss bar has a base electrically coupled to each of the outer shields to electrically common the outer shields. The buss bar has ground tines extending from the base positioned between signal contacts and configured to be terminated to corresponding ground pads of the host circuit board.
Optionally, the signal contacts may be terminated to the signal conductors via a solderless connection. The signal contacts may have spring beams configured to be spring biased against the signal pads of the host circuit board. The signal contacts may include mating interfaces configured to be surface mounted to the corresponding signal pads of the host circuit board and the ground tines may include mating interfaces configured to be surface mounted to the corresponding ground pads of the host circuit board at separable interfaces. The ground tines may extend forward of the signal contacts such that the mating interfaces of the ground tines are positioned further from the signal conductors than the mating interfaces of the signal contacts.
Optionally, the ground tines may be electrically connected to the host circuit board without the use of a paddle card therebetween. The buss bar may be a stamped and formed structure with the ground tines integrally formed with the base. The ground tines may provide electrical shielding along ground planes defined between pairs of the signal contacts and corresponding signal conductors. The buss bar may include an insulator between the base and the signal contacts and signal conductors to electrically isolate the base from the signal contacts and the signal conductors.
Optionally, each RF cable may comprise a twin axial RF cable including an insulator between the signal conductor and corresponding outer shield, a jacket surrounding each outer shield and a sleeve surrounding both jackets of each pair. The outer shield may be exposed forward of the corresponding jackets and sleeve and the buss bar may directly engaging the exposed portions of the outer shields.
In another embodiment, an RF cable connector is provided having a cable assembly having a plurality of twin axial RF cables bundled together and a buss bar coupled to the cable assembly. Each twin axial RF cable has a pair of signal conductors surrounded by an outer shield. The cable assembly has signal contacts terminated to ends of the signal conductors configured to be surface mounted to corresponding signal pads of a host circuit board. The buss bar has a base electrically coupled to each of the outer shields to electrically common the outer shields. The buss bar has ground tines extending from the base positioned between signal contacts. The ground tines are configured to be surface mounted to corresponding ground pads of the host circuit board. The RF cable connector includes an insulator having a cable end, a plurality of tine channels and a plurality of contact channels. The insulator is positioned forward of the cable assembly with the signal contacts being loaded into corresponding contact channels and with the ground tines being loaded into corresponding tine channels. The insulator supports the signal contacts and the ground tines for surface mounting to the host circuit board. The RF cable connector includes a housing receiving the insulator that has a latch extending therefrom. The RF cable connector includes a host circuit board having signal pads and ground pads at a mating area of the host circuit board and an EMI hood covering the mating area. The housing is loaded into the EMI hood with the signal contacts engaging corresponding signal pads and with the ground tines engaging corresponding ground pads. The latch of the housing engages the EMI hood to secure the housing to the EMI hood.
The host circuit board 102 includes front edge 110 where the cable assembly 106 is connected to the host circuit board 102. The host circuit board 102 includes a mounting surface 112 extending from the front edge 110. The RF cable connector 100 is coupled to the mounting surface 112 of the host circuit board 102. In an exemplary embodiment, the host circuit board 102 includes one or more electronic components 114 coupled thereto. The electronic components 114 may process data signals sent to and/or received from the RF cable connector 100. The host circuit board 102 includes conductors or traces connecting the RF cable connector 100 with the electronic components 114.
In an exemplary embodiment, the host circuit board 102 includes an EMI hood 116 covering a mating area of the host circuit board 102. The EMI hood 116 provides electrical shielding for the RF cable connector 100 and signal conductors of the host circuit board 102. The EMI hood 116 includes a receptacle 118 that receives the housing 104 of the RF cable connector 100. In an exemplary embodiment, the housing 104 may be secured to the EMI hood 116 to secure the RF cable connector 100 to the host circuit board 102. In an exemplary embodiment, the RF cable connector 100 is separable from the host circuit board 102, wherein the RF cable connector 100 may be mated and unmated from the host circuit board 102.
The cables 122 are prepared by exposing portions of the cables 122 for termination to other components. For example, portions of the outer shield 128 are exposed beyond the jacket 130 and sleeves 134. Portions of the signal conductors 124 are exposed beyond the outer shields 128. In an exemplary embodiment, signal contacts 140 are terminated to ends 142 of the signal conductors 124. Optionally, the signal contacts 140 may be solderlessly connected, such as being crimped, to the signal conductors 124. The signal contacts 140 form part of data communication path of each signal conductor 124. The signal contacts 140 are configured to be directly electrically coupled to the host circuit board 102 (shown in
In an exemplary embodiment, each signal contact 140 includes a crimp barrel 144 at an end thereof. A beam 146 extends from the crimp barrel 144. Optionally, the beam 146 may define a spring beam configured to be deflectable and spring biased against the host circuit board 102 to define a separable mating interface with the host circuit board 102. The beam 146 has a mating portion 148 defining a separable mating interface 150. The mating interface 150 is configured to engage the host circuit board 102. In the illustrated embodiment, the mating portion 148 is bent downward into a V-shape to define the mating interface 150 at the base of the V-shaped area. The beam 146 may have other shapes in alternative embodiments. In an exemplary embodiment, the signal contact 140 is stamped and formed.
The buss bar 152 includes a base 154 extending the width of the cable assembly 106. The buss bar 152 includes ground tines 156 extending forward from the base 154. The ground tines 156 are positioned between corresponding signal contact 140. For example, each ground tine 156 may extend between otherwise adjacent pairs of the signal contacts 140. The ground tines 156 are configured to be surface mounted to the host circuit board 102 at a separable mating interface when the RF cable connector 100 is coupled to the host circuit board 102 (shown in
In an exemplary embodiment, the buss bar 152 is a stamped and formed structure. The ground tines 156 are integral with the base 154. The ground tines 156 include mating portions 158 proximate to ends thereof. The mating portions 158 define mating interfaces 160 configured to be electrically connected to the host circuit board 102. The mating interfaces 160 define separable mating interfaces configured to be repeatedly mated to and unmated from the host circuit board 102. In the illustrated embodiment, the mating portions 158 are bent downward in a V-shape to define the mating interfaces 160 at the bottom of the V-shaped area. Other shapes are possible in alternative embodiments for the ground tines 156.
Optionally, the buss bar 152 may include tabs 162 at ends thereof that are used to secure the buss bar 152 to the cable assembly 106. The tabs 162 may be folded over around a bottom side of the cable assembly 106. Other securing features may be used in alternative embodiments to secure the buss bar 152 to the cable assembly 106.
The RF cable connector 100 includes an insulator 170 used to hold the signal contacts 140 and the ground tines 156 of the buss bar 152. The insulator 170 is configured to be loaded into the housing 104. The housing 104 provides electrical shielding for the signal contact 140 received in the insulator 170. The insulator 170 is made from an insulative material, such as a plastic material. The insulator 170 has a front end 172 and a cable end 174 opposite the front end 172. The insulator 170 has a top 176 and a bottom 178. During assembly, the cable assembly 106 is loaded into the cable end 174 of the insulator 170.
The insulator 170 includes contact channels 180 that receive corresponding signal contacts 140. The insulator 170 includes tine channels 182 that receive corresponding ground tines 156. The insulator 170 holds the proper spacing of the signal contacts 140 and the ground tines 156 such that the mating interfaces 150, 160 are exposed and properly positioned for mating with the host circuit board 102. In the illustrated embodiment, the insulator 170 is generally rectangular in shape, however other shapes are possible in alternative embodiments.
The housing 104 is configured to receive the insulator 170 and portions of the cable assembly 106. The housing 104 may be manufactured from a metallic material. The housing 104 provides electrical shielding for the signal contacts 140. Optionally, the housing 104 may be directly connected to the buss bar 152 to create a ground path between the buss bar 152 and the housing 104.
The housing 104 defines a receptacle 190. The insulator 170 is loaded into the receptacle 190. A bottom 192 of the housing 104 may include openings 194 that receive the mating portion 148 of the signal contacts 140 and mating portion 158 of the ground tines 156. The openings 194 expose the signal contacts 140 and ground tines 156 for connection to the host circuit board 102.
In an exemplary embodiment, the housing 104 includes a latch 196 coupled thereto. Optionally, the latch 196 may be rotatably coupled to the housing 104. Other types of latches or securing features may be used in alternative embodiments for securing the RF cable connector 100 to the host circuit board 102.
The buss bar 152 is secured to the RF cables 122. Optionally, the buss bar 152 may be clamped onto one or more of the RF cables 122 and/or signal contacts 140. The buss bar 152 may be secured to the holder 200. The base 154 directly engages the outer shields 128 of each of the wires 132 to electrically common each of the outer shields 128. Optionally, the outer shields 128 may be soldered to the base 154. The outer shields 128 may be mechanically and electrically connected to the base 154 by other means or processes in alternative embodiments. For example, the base 154 may be welded to the outer shields 128, such as by ultrasonically welding the base 154 to the outer shield 128.
In an exemplary embodiment, an insulator 202 is positioned between the base 154 and each of the signal contact 140 and signal conductors 124. For example, the insulator 202 may be applied to an inner surface of the base 154 forward of the area where the outer shields 128 are connected to the base 154. Optionally, the insulator 202 may be secured to the base 154 by adhesive. The insulator 202 may be a film or a tape applied to the base 154. The insulator 202 electrically isolates the buss bar 152 from the signal conductors 124 and the signal contacts 140.
When assembled, the ground tines 156 extend forward from the base 154 along the signal contacts 140. In an exemplary embodiment, the ground tines 156 extend forward of the distal ends of the signal contacts 140. For example, the ground tines 156 may be longer than the signal contacts 140 to position the mating interfaces 160 of the ground tines 156 forward of the mating interfaces 150 of the signal contacts 140. In an exemplary embodiment, the ground tines 156 are positioned between the corresponding signal contacts 140. For example, the ground tines 156 may be positioned between pairs of the signal contacts 140. The ground tines 156 may be positioned along ground planes extending between pairs of the signal contacts 140. Optionally, portions of the ground tines 156 may be vertically aligned (e.g., coplanar with) portions of the signal contacts 140.
The buss bar 252 includes a base 254 and ground tines 256 extending forward from the base 254. The ground tines 256 are different than the ground tines 156 (shown in
The ground tines 256 include mating portions 258 proximate to ends thereof. The mating portions 258 define mating interfaces 260 configured to be electrically connected to the host circuit board 102. The mating interfaces 260 define separable mating interfaces configured to be repeatedly mated to and unmated from the host circuit board 102. In the illustrated embodiment, the mating portions 258 are formed by bumps or protrusions that extend downward to define the mating interfaces 260 at the bottom of the protrusion. Other shapes are possible in alternative embodiments for the ground tines 256.
It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Dimensions, types of materials, orientations of the various components, and the number and positions of the various components described herein are intended to define parameters of certain embodiments, and are by no means limiting and are merely exemplary embodiments. Many other embodiments and modifications within the spirit and scope of the claims will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means-plus-function format and are not intended to be interpreted based on 35 U.S.C. §112, sixth paragraph, unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure.
