Patent Publication Number: US-8992253-B2

Title: Electrical connector for transmitting data signals

Description:
BACKGROUND OF THE INVENTION 
     The subject matter herein relates generally to an electrical connector having signal conductors for transmitting differential signals between electrical components that are communicatively coupled through the electrical connector. 
     Networking and telecommunication systems use electrical connectors to interconnect different components of the systems. For example, the interconnected electrical components may be a motherboard and a daughter card. The electrical connectors are configured to transmit differential signals (e.g., data signals) through multiple signal conductors between the interconnected components. As speed and performance demands of the systems increase, however, conventional electrical connectors are proving to be insufficient. For example, signal loss and signal degradation are challenging issues for some electrical connectors. There is also a demand to increase the density of signal conductors to increase throughput. Moreover, there has been a general trend for smaller electrical devices, including smaller electrical connectors. Increasing the density of signal conductors while also decreasing the size of the electrical connectors, however, renders it more difficult to improve the speed and performance of the electrical connectors. 
     Another issue that may arise when developing an electrical connector is referred to as skew. Skew can occur when signal conductors of a common differential pair extend through the electrical connector with different path lengths. For instance, some right-angle connectors may be arranged “in-column” such that the two signal conductors of a conductor pair substantially coincide within a common plane. Due to the right-angle configuration and the in-column arrangement, the signal conductors have different physical path lengths. As such, the signals propagating through the two signal conductors have different distances to travel. 
     Different solutions to the skew problem have been proposed. Skew may be addressed outside of the electrical connector within one of the electrical components (e.g., circuit board) that the electrical connector engages. However, skew can also be addressed within the electrical connector. For example, the path of what would be the shorter signal conductor may be redirected to effectively increase the physical path length. Intentionally increasing the physical path lengths of the signal conductors, however, may increase the size of the electrical connector or lead to other challenges with respect to signal loss and degradation. As another example, some known connectors have used air trenches in which a portion of the signal conductor is exposed to air within the connector. Other connectors have used signal conductors that have “flags.” A flag is a portion of the signal conductor that has greater cross-sectional dimensions than another portion of the same signal conductor. However, it can be challenging to manufacture electrical connectors with air trenches or flags because even relatively small manufacturing tolerances can lead to a large change in skew. 
     Accordingly, there is a need for additional solutions for reducing or eliminating skew between signal conductors that are configured for differential signaling within an electrical connector. 
     BRIEF DESCRIPTION OF THE INVENTION 
     In one embodiment, an electrical connector is provided that includes a connector body having a mating side and a mounting side that are configured to engage respective electrical components. The electrical connector also includes a conductor pair having first and second signal conductors extending through the connector body along respective paths between the mating and mounting sides. The first signal conductor has a height and a thickness taken transverse to a direction of the respective path and includes a flag segment and a base segment. The height of the first signal conductor along the flag segment is greater than the height of the first signal conductor along the base segment. The electrical connector also includes a dielectric body extending between the mating and mounting sides and surrounding the conductor pair. The dielectric body has a signal-control trench that extends along and exposes the flag segment to an air dielectric within the signal-control trench. The signal-control trench has a height that is measured along the height of the flag segment. The height of the signal-control trench is less than the height of the flag segment. 
     In certain embodiments, the conductor pair is a first conductor pair and the dielectric body is a first dielectric body, wherein the electrical connector also includes a second conductor pair and a second dielectric body. The second conductor pair has first and second signal conductors that extend between the mating and mounting sides and are surrounded by the second dielectric body. Optionally, the second dielectric body may have a corresponding signal-control trench that exposes a portion of the corresponding first signal conductor of the second conductor pair. The signal-control trenches of the first and second dielectric bodies may have different lengths. Also optionally, the first and second conductor pairs may be arranged co-planar with respect to each other such that the first and second signal conductors of the first conductor pair and the first and second signal conductors of the second conductor pair substantially coincide along a common plane. 
     In another embodiment, an electrical connector is provided that includes a connector body having a mating side and a mounting side that are configured to engage respective electrical components. The electrical connector also includes a conductor pair having first and second signal conductors extending through the connector body along respective paths between the mating and mounting sides. The first signal conductor has a height and a thickness taken transverse to a direction of the respective path and includes a flag segment and a base segment. The height of the first signal conductor along the flag segment is greater than the height of the first signal conductor along the base segment. The first signal conductor has a broadside surface. The electrical connector also includes a dielectric body extending between the mating and mounting sides and surrounding the conductor pair. The dielectric body has a signal-control trench that extends along and exposes the broadside surface along the flag segment. The broadside surface has an exposed area that interfaces with an air dielectric of the signal-control trench and a covered area that is directly engaged to and covered by the dielectric body. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a connector system formed in accordance with one embodiment. 
         FIG. 2  is a front perspective view of an electrical connector formed in accordance with one embodiment. 
         FIG. 3  is an exploded view of a contact module that may be used with the electrical connector. 
         FIG. 4  is a side view of a leadframe that may be used to assemble an electrical connector in accordance with one embodiment. 
         FIG. 5  is a perspective cross-section of a pathway assembly of the leadframe that may be used by the electrical connector. 
         FIG. 6  is a side view of a portion of the pathway assembly. 
         FIG. 7  is a cross-section taken along the line  7 - 7  in  FIG. 6  of the pathway assembly. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Embodiments described herein include connector systems (e.g., communication systems) and electrical connectors that are configured to transmit data signals. The electrical connectors are configured to engage other electrical components of the systems. The electrical components may be, for example, other electrical connectors, circuit boards, or other components capable of transmitting data signals. In particular embodiments, the systems and the electrical connectors set forth herein are configured for high-speed signal transmission, such as 10 Gbps, 20 Gbps, or more. Embodiments may include pairs of signal conductors that are surrounded by one or more dielectric bodies. The dielectric body may hold the signal conductors. For example, a dielectric body may be an overmold that separates the signal conductor from adjacent signal conductors and/or other conductive material. The dielectric body may be shaped or formed to intimately engage one or more surfaces (hereinafter referred to as covered areas) but to also expose one or more other surfaces (hereinafter referred to as exposed areas). The amount of exposure may be predetermined in order to achieve a target electrical performance. 
       FIG. 1  is a perspective view of a connector system  100  formed in accordance with one embodiment. The connector system  100  includes a midplane assembly  102 , a first connector assembly  104  configured to be coupled to one side of the midplane assembly  102 , and a second connector assembly  106  configured to be connected to another side of the midplane assembly  102 . The midplane assembly  102  is used to electrically connect the first and second connector assemblies  104 ,  106 . Optionally, the first connector assembly  104  may be part of a daughter card and the second connector assembly  106  may be part of a backplane, or vice versa. In other embodiments, the connector assemblies  104 ,  106  may be part of a cabled backplane system. The first and second connector assemblies  104 ,  106  may also be line cards or switch cards. Alternatively, the connector assemblies  104 ,  106 , with modification, may be directly connected without the use of the midplane assembly  102 . 
     The midplane assembly  102  includes a midplane circuit board  110  having a first side  112  and second side  114  that face in opposite directions. The midplane assembly  102  includes a first header assembly  116  mounted to and extending from the first side  112  of the circuit board  110 . The midplane assembly  102  includes a second header assembly  118  mounted to and extending from the second side  114  of the circuit board  110 . The first and second header assemblies  116 ,  118  each include signal contacts  120  electrically connected to one another through the circuit board  110 . 
     The midplane assembly  102  includes a plurality of signal pathways therethrough defined by the signal contacts  120  and conductive vias (not shown) that extend through the circuit board  110 . Each signal pathway through the midplane assembly  102  is defined by a signal contact  120  of the first header assembly  116  and a signal contact  120  of the second header assembly  118 , which may both be received in a common conductive via through the circuit board  110 . In an exemplary embodiment, the signal pathways pass straight through the midplane assembly  102  along linear paths. Such a design of the circuit board  110  is less complex and less expensive to manufacture than a circuit board that routes traces between different vias to connect the first and second header assemblies  116 ,  118 . 
     The first and second header assemblies  116 ,  118  include ground shields  122  that provide electrical shielding around corresponding signal contacts  120 . In an exemplary embodiment, the signal contacts  120  may be pin-like and arranged in pairs configured to convey differential signals. The ground shields  122  may have panels or sides that peripherally surround a corresponding pair of the signal contacts  120 . For example, the ground shields  122  may be C-shaped or L-shaped. 
     The first connector assembly  104  includes a first circuit board  130  and a first electrical connector  132  coupled to the circuit board  130 . The electrical connector  132  is configured to be coupled to the first header assembly  116 . The electrical connector  132  includes a connector body  138  that is formed from a shroud  139  and a plurality of contact modules  140  that are held by the shroud  139 . The contact modules  140  are held in a stacked configuration generally parallel to one another. The contact modules  140  hold a plurality of signal contacts (not shown) that are electrically connected to the circuit board  130  and define signal pathways through the electrical connector  132 . The signal contacts may be arranged in pairs carrying differential signals. 
     The second connector assembly  106  includes a second circuit board  150  and a second electrical connector  152  coupled to the circuit board  150 . The electrical connector  152  is configured to be coupled to the second header assembly  118 . The electrical connector  152  has a mating side  154  configured to be mated with the second header assembly  118 . The electrical connector  152  has a mounting side  156  configured to be mated with the circuit board  150 . In an exemplary embodiment, the mounting side  156  is oriented perpendicular with respect to the mating side  154 . When the electrical connector  152  is coupled to the second header assembly  118 , the circuit board  150  is oriented perpendicular with respect to the circuit board  110 . The circuit board  150  is oriented perpendicular to the circuit board  130 . 
     The electrical connector  152  includes a connector body  158  that is formed from a shroud  159  and a plurality of contact modules  160  that are held by the shroud  159 . The connector body  158  includes the mating and mounting sides  154 ,  156 . The contact modules  160  are held in a stacked configuration generally parallel to one another. The contact modules  160  hold a plurality of signal contacts  162  (shown in  FIG. 2 ) that are electrically connected to the circuit board  150  and partially define signal pathways that extend through the electrical connector  152 . The signal contacts  162  are configured to be electrically connected to the signal contacts  120  of the second header assembly  118 . In an exemplary embodiment, the contact modules  160  provide electrical shielding for the signal contacts  162 . The signal contacts  162  may be arranged in pairs carrying differential signals. In an exemplary embodiment, the contact modules  160  generally provide 360° shielding for each pair of signal contacts  162  along substantially the entire length of the signal contacts  162  between the mounting side  156  and the mating side  154 . The shield structure of the contact modules  160  that provides the electrical shielding for the pairs of signal contacts  162  is electrically connected to the ground shields  122  of the second header assembly  118  and is electrically connected to a ground plane of the circuit board  150 . 
     In the illustrated embodiment, the circuit board  130  is oriented generally horizontally. The contact modules  140  of the electrical connector  132  are oriented generally vertically. The circuit board  150  is oriented generally vertically. The contact modules  160  of the electrical connector  152  are oriented generally horizontally. The first connector assembly  104  and the second connector assembly  106  have an orthogonal orientation with respect to one another. The signal contacts within each differential pair, including the signal contacts of the electrical connector  132 , the signal contacts  162  of the electrical connector  152 , and the signal contacts  120 , are all oriented generally horizontally. The contact modules  140  and/or  160  may be configured to be terminated to cables rather than circuit boards, with conductors of the cables terminated to corresponding conductors of the contact modules  140  and/or  160 . 
       FIG. 2  is a front perspective view of the electrical connector  152  and illustrates one of the contact modules  160 , which is configured for loading into the shroud  159 . The mating side  154  of the connector body  158  includes a plurality of signal contact openings  164  and a plurality of ground contact openings  166 . The contact modules  160  and the shroud  159  collectively form the connector body  158 . The signal contacts  162  are received in corresponding signal contact openings  164  of the shroud  159 . The ground contact openings  166  of the shroud  159  are configured to receive corresponding ground shields  122  ( FIG. 1 ) and grounding members, such as grounding beams of the contact modules  160 . 
       FIG. 3  is an exploded view of an exemplary contact module  160 . The contact module  160  includes a conductive holder  170 , which in the illustrated embodiment includes a first holder member  172  and a second holder member  174  that are coupled together to form the conductive holder  170 . The conductive holder  170  has a mating edge  176  and a mounting edge  178 . In some embodiments, when the contact modules  160  are stacked side-by-side, such as shown in  FIG. 2 , the mounting edges  178  may collectively form or partially define the mounting side  156  ( FIG. 1 ). 
     The holder members  172 ,  174  are fabricated from a conductive material. For example, the holder members  172 ,  174  may be die cast from a metal material. Alternatively, the holder members  172 ,  174  may be stamped and formed or may be fabricated from a plastic material that has been metalized or coated with a metallic layer. By having the holder members  172 ,  174  fabricated from a conductive material, the holder members  172 ,  174  may provide electrical shielding for the electrical connector  152  ( FIG. 1 ). When the holder members  172 ,  174  are coupled together, the holder members  172 ,  174  define at least a portion of a shield structure to provide electrical shielding for signal pathways that extend through the electrical connector  152 . The conductive holder  170  may be manufactured from a single piece rather than the two holder members  172 ,  174 . In other embodiments, the holder  170  may not be conductive, but rather may rely on separate shields or may be unshielded. 
     The conductive holder  170  is configured to hold a frame assembly  180 . In the illustrated embodiment, the frame assembly  180  includes first pathway assemblies  186  and second pathway assemblies  188 . Each of the pathway assemblies  186 ,  188  includes a signal conductor  191  and respective dielectric bodies,  187 ,  189 . Each of the signal conductors  191  of the pathway assemblies  186 ,  188  is electrically coupled to a corresponding signal contact  162 . In some embodiments, the pathway assemblies  186 ,  188  may be manufactured by overmolding the corresponding signal conductors  191  and signal contacts  162  with a dielectric material thereby forming the respective dielectric bodies  187 ,  189 . The pathway assemblies  186  may be coupled to one another through one or more joints  197 , and the pathway assemblies  188  may be coupled to one another through one or more joints  198 . 
     In some cases, the first and second pathway assemblies  186 ,  188  may be coupled to each other to form the frame assembly  180 . When the frame assembly  180  is formed, one or more of the pathway assemblies  186  may be positioned between adjacent pathway assemblies  188  and/or one or more of the pathway assemblies  188  may be positioned between adjacent pathway assemblies  186 .  FIG. 3  shows three first pathway assemblies  186  and three second pathway assemblies  188 . When the first and second pathway assemblies  186 ,  188  are coupled together to form the frame assembly  180 , the frame assembly  180  has a total of six pathway assemblies that are co-planar with respect to each other (e.g., the pathway assemblies  186 ,  188  substantially coincide with a common plane). 
     Although certain embodiments may be formed through an overmolding process, other manufacturing processes may be utilized to form the pathway assemblies  186 ,  188  and the electrical connector  152 . For example, each of the dielectric bodies  187 ,  189  may be constructed from separate dielectric shells. To construct the corresponding pathway assembly, the two dielectric shells may be coupled to each other with the corresponding signal conductor therebetween. 
     The holder members  172 ,  174  provide shielding around the frame assembly  180 . The holder members  172 ,  174  include tabs  182 ,  184  that extend inward toward one another to extend into the frame assembly  180 . The tabs  182 ,  184  define at least a portion of a shield structure that provides electrical shielding around the signal contacts  162 . The tabs  182 ,  184  are configured to extend into the frame assembly  180  such that the tabs  182 ,  184  are positioned between pairs of the signal contacts  162  to provide shielding between the corresponding pairs of the signal contacts  162 . 
     The holder members  172 ,  174  provide electrical shielding between and around respective pairs of signal pathways. A single signal pathway of the contact module  160  may include, for example, a signal contact  162  and the corresponding signal conductor  191  that is electrically coupled to the signal contact  162 . The holder members  172 ,  174  provide shielding from electromagnetic interference (EMI) and/or radio frequency interference (RFI). The holder members  172 ,  174  may provide shielding from other types of interference as well. The holder members  172 ,  174  may prevent crosstalk between different pairs of signal contacts  162 . The holder members  172 ,  174  may control electrical characteristics, such as impedance control, crosstalk control, and the like, of the signal contacts  162  and the signal conductors  191 . The holder members  172 ,  174  may also provide shielding for the signal contacts  162  from adjacent contact modules. 
     In an exemplary embodiment, the contact module  160  includes a first ground shield  190  and a second ground shield  192  that provide shielding for the signal contacts  162 . The ground shields  190 ,  192  make ground terminations to the ground shields  122  ( FIG. 1 ) and the circuit board  150  ( FIG. 1 ). In an exemplary embodiment, the ground shields  190 ,  192  are internal ground shields positioned within the conductive holder  170 . The ground shields  190 ,  192  are inlaid within the conductive holder  170 . For example, the first ground shield  190  is laid in the first holder member  172  and positioned between the first holder member  172  and the frame assembly  180 . The second ground shield  192  is laid in the second holder member  174  and positioned between the second holder member  174  and the frame assembly  180 . The dielectric bodies  187 ,  189  may be located between the ground shields  190 ,  192  when the contact module  160  is constructed. 
       FIG. 4  is a side view of an overmolded leadframe  200  formed in accordance with one embodiment that includes a plurality of pathway assemblies  230 A- 230 C. The leadframe  200  and a similar leadframe may be used to form, with modification, the pathway assemblies  186  and the pathway assemblies  188 , respectively, shown in  FIG. 3 . The leadframe  200  may be formed from sheet metal that is stamped and/or etched to define the various features of the leadframe  200 . The sheet metal may be copper, copper alloy, or another metal that is capable of transmitting electrical current. The leadframe  200  may be overmolded with a dielectric material to form a frame structure  204 . The frame structure  204  includes a plurality of dielectric bodies  210 . 
     The leadframe  200  includes a plurality of conductor pairs  201 A- 201 C. Each of the conductor pairs  201 A- 201 C is surrounded by a corresponding dielectric body  210 , and each of the conductor pairs  201 A- 201 C includes a first signal conductor  212  and a second signal conductor  214  that extend proximate to each other along similarly-shaped paths. The first and second signal conductors  212 ,  214  are configured to transmit differential signals. As shown, the first and second signal conductors  212 ,  214  are indicated by dashed lines along the corresponding dielectric bodies  210 . The first signal conductors  212  are also visible through corresponding air holes  223  and signal-control trenches  224 , which are voids in the dielectric material of the corresponding dielectric bodies  210 . The second signal conductors  214  are also visible through corresponding air holes  227  in the illustrated embodiment. In the illustrated embodiment, the signal conductors  212 ,  214  are shaped for a right-angle electrical connector, such as the electrical connectors  132 ,  152  ( FIG. 1 ). In other embodiments, however, the signal conductors  212 ,  214  may be shaped for a vertical connector. 
     The signal conductors  212  have mounting and mating ends  216 ,  218  and extend lengthwise therebetween. The signal conductors  214  have mounting and mating ends  220 ,  222  and extend lengthwise therebetween. The mating ends  218 ,  222  may also be referred to as signal contacts, such as the signal contacts  162 . As shown, the signal conductors  212 ,  214  of each conductor pair  201 A- 201 C have different physical path lengths with respect to each other. The path lengths of the signal conductors  212  may be measured between corresponding mounting and mating ends  216 ,  218 , and the path lengths of the signal conductors  214  may be measured between the corresponding mounting and mating ends  220 ,  222 . In the illustrated embodiment, for each conductor pair  201 A- 201 C, the physical path length of the corresponding signal conductor  212  is greater than the physical path length of the corresponding signal conductor  214  of the same conductor pair such that the signal conductors  212 ,  214  have an inherent skew. In  FIG. 4 , the leadframe  200  has a total of three (3) conductor pairs  201 A- 201 C and a total of six (6) signal conductors  212 ,  214 , but a different number of conductor pairs and signal conductors may be used in alternative embodiments. 
     The dielectric bodies  210  are elongated structures that surround the respective conductor pairs  201 A- 201 C. For example, the dielectric bodies  210  may encase the signal conductors  212 ,  214  of the respective conductor pair. When the dielectric bodies  210  are molded or otherwise positioned to surround the signal conductors  212 ,  214  of the conductor pairs  201 A- 201 C, the respective pathway assemblies  230 A- 230 C are formed. The dielectric bodies  210  are configured to extend between mating and mounting sides of the electrical connector, such as the mating and mounting sides  154 ,  156  ( FIG. 1 ) of the electrical connector  152 . The mating ends  218 ,  222  are configured to be positioned proximate to the mating side so that the mating ends  218 ,  222  may directly engage respective signal contacts (not shown) of the mating connector, such as the header assembly  118  ( FIG. 1 ). The mounting ends  216 ,  220  are configured to be positioned proximate to a mounting side so that the mounting ends  216 ,  220  may directly engage respective plated thru-holes (not shown) of a circuit board, such as the circuit board  150  ( FIG. 1 ). 
     As described herein, the air holes  223  and signal-control trenches  224  may be configured to control an electrical performance of the corresponding pathway assembly. In some embodiments, the signal-control trenches  224  may be sized and shaped relative to the associated signal conductors  212  to accommodate skew that is formed by the path lengths of the signal conductors  212 ,  214  of the corresponding pathway assemblies  230 A- 230 C. The air holes  223  and the signal-control trenches  224  may be formed during an overmolding process. For example, the leadframe  200  may be positioned within a shaping mold (not shown) and a liquid dielectric material may be injected into the shaping mold. The shaping mold may include projections that directly engage (e.g., press against) surfaces of the signal conductors  212 ,  214  so that the air holes  223  and the signal-control trenches  224  exist after the dielectric material cures or sets. In an alternative manufacturing method, each of the dielectric bodies  210  may completely surround the respective conductor pairs  201 A- 201 C such that the signal conductors are not exposed to the surrounding environment. Subsequently, the dielectric bodies  210  may be removed (e.g., etched) to expose surfaces of the signal conductors  212 ,  214 . 
     The pathway assemblies  230 A- 230 C may be similar to the pathway assemblies  186 ,  188  ( FIG. 3 ). For example, adjacent pathway assemblies  230 A,  230 B or  230 B,  230 C may be coupled to each other through a joint  232  that extends across and directly couples the two pathway assemblies. The joints  232  may be similar to the joints  197 ,  198  described above with respect to  FIG. 3 . In some embodiments, the pathway assemblies  230 A- 230 C form only a part of one column of pathway assemblies. For example, the three pathway assemblies  230 A- 230 C may be inter-nested with two or three other pathway assemblies from another leadframe. For example, another pathway assembly may be positioned in the space between the adjacent pathway assemblies  230 A,  230 B, or another pathway assembly may be positioned in the space between the adjacent pathway assemblies  230 B,  230 C. In some embodiments, the joints  232  may include respective holes or openings  234 . The holes  234  may receive posts from another overmolded leadframe  200  to join the overmolded leadframes. 
       FIG. 5  is a perspective view of a cross-section of one of the pathway assemblies  230 . The dielectric body  210  includes a plurality of body surfaces  241 - 244  including opposite edge surfaces  241 ,  242  and opposite side surfaces  243 ,  244 . The dielectric body  210  surrounds the signal conductors  212 ,  214 . In the illustrated embodiment, the dielectric body  210  is shaped to expose surfaces of the signal conductors  212 ,  214 . For example, the signal-control trench  224  and a signal-control trench  254  may expose corresponding portions of the signal conductor  212  to air dielectrics  246  that are defined by the corresponding signal-control trench. 
     The air holes  227  may also expose portions of the signal conductor  214  to an air dielectric. Although not shown, there may be additional air holes along the side surface  244  that expose the signal conductor  214  and/or signal conductor  212 . The signal-control trenches  224 ,  254  and the air holes  227  are cavities or voids in the dielectric body  210 . In particular embodiments, the signal-control trenches  224 ,  254  and the air holes  227  expose the signal conductors  212 ,  214  to air within a contact module, such as the contact module  160  ( FIG. 1 ), that defines a portion of the connector body. For example, the dielectric body  210  may be sandwiched between holder members, such as the first and second holder members  172 ,  174  ( FIG. 3 ). 
     As shown, the signal-control trenches  224 ,  254  are directly opposite each other such that the signal-control trenches  224 ,  254  may constitute a single window  248  that would extend entirely through the dielectric body  210  and the side surfaces  243 ,  244  if it were not for the signal conductor  212 . In other embodiments, only one of the signal-control trenches  224 ,  254  may be extend along the signal conductor  212 . In the illustrated embodiment, the side surfaces  243 ,  244  and the edge surfaces  241 ,  242  define a generally rectangular or block-shaped cross-section of the dielectric body  210 , except for portions of the dielectric body  210  that include the signal-control trenches  224 ,  254  and the air holes  223  ( FIG. 4 ) or  227 . 
     The signal conductors  212 ,  214  may have substantially rectangular cross-sections that are formed when, for example, the sheet material is stamped to form the leadframe  200  ( FIG. 4 ). Accordingly, the signal conductors  212 ,  214  of one conductor pair may substantially coincide with a common plane  300 . In some embodiments, the electrical connectors set forth herein may include “in-column” conductor pairs, wherein each of the signal conductors  212 ,  214  of the conductor pairs substantially coincide with the common plane  300 . For example, the conductor pairs  201 A- 201 C may substantially coincide with the common plane  300  in some embodiments. 
       FIG. 6  is a side view of an enlarged portion of the pathway assembly  230 . The signal conductor  212  is shown through the signal-control trench  224  in the dielectric body  210  and also by phantom lines. Likewise, the signal conductor  214  is shown through the air holes  227  in the dielectric body  210  and also by phantom lines. As shown by the phantom lines, the signal conductor  212  may include at least one flag segment  250  and first and second base segments  252 ,  253  that the flag segment  250  extends between and joins. Embodiments set forth herein may include signal conductors having segments with different cross-sectional dimensions. For example, the signal conductor  212  has a height  256  along the flag segment  250  and a second height  258  along the base segments  252 ,  253 . The height  256  is greater than the height  258 . 
     Also shown in  FIG. 6 , the signal-control trench  224  has a length  260  and a height  262 . The height  262  is measured along the height  256  of the flag segment  250  (e.g., measured along a common axis so that the values can be compared). The heights  262 ,  256  may be measured along the common plane  300  ( FIG. 5 ) in the same direction that is transverse to the path of the signal conductor  212 . More specifically, the height  256  may be measured between opposite edge surfaces  271 ,  272  (shown in  FIG. 7 ) of the signal conductor  212 , and the height  262  may be measured between opposite interior surfaces of the signal trench  224 , such as interior surfaces  275 ,  276  (shown in  FIG. 7 ). In particular embodiments, the height  262  of the signal-control trench  224  is shorter than the height  256  of the flag segment  250 . The height  262  may be substantially equal to the height  258  of the base segments  252 ,  253 . 
     The flag segment  250  has a length  264 , which may be measured along the length  260  of the signal-control trench  224 . In the illustrated embodiment, the length  264  is equal to the length  260  of the signal-control trench  224 . Also shown, the length  264  of the flag segment  250  directly overlaps with the length  260  of the signal-control trench  224 . More specifically, the flag segment  250  may begin immediately at a beginning of the signal-control trench  224  at point A in  FIG. 6 , and the flag segment  250  may end immediately with the signal-control trench  224  at point B in  FIG. 6 . 
       FIG. 7  is an enlarged cross-section of the dielectric body  210  and the signal conductor  212  at the flag segment  250  taken transverse to the path of the signal conductor  212 . As shown, the signal conductor  212  includes conductor surfaces  271 - 274  including opposite edge surfaces  271 ,  272  and opposite broadside surfaces  273 ,  274 . The edge surfaces  271 ,  272  may be directly engaged by the dielectric body  210 . In some embodiments, the edge surfaces  271 ,  272  may be stamped edges that are formed when the leadframe  200  ( FIG. 4 ) is stamped from a conductive sheet of material. The signal conductor  212  has a thickness  286  along the flag segment  250  that is measured between the opposite broadside surfaces  273 ,  274 . As shown, the broadside surfaces  273 ,  274  are located respective depths  287 ,  288  from the respective side surfaces  243 ,  244 . 
     The signal-control trench  224  is defined by opposite interior surfaces  275 ,  276  and the broadside surface  273  that extends between the interior surfaces  275 ,  276 . The signal-control trench  254  is defined by opposite interior surfaces  277 ,  278  and the broadside surface  274  that extends between the interior surfaces  277 ,  278 . As shown, the interior surfaces  275 ,  277  and the edge surface  271  may substantially coincide with a surface plane  280 . In the illustrated embodiment, the interior surfaces  276 ,  278  substantially coincide with a surface plane  281 . 
     The edge surface  272 , however, is not co-planar with the interior surfaces  276 ,  278  and does not coincide with the surface plane  281 . Instead, the edge surface  272  may be embedded within the dielectric body  210  such that the edge surface  272  directly engages the dielectric body  210  and proximate portions of the broadside surfaces  273 ,  274  also directly engage the dielectric body  210 . As used herein, elements may “directly engage” each other when surfaces of the elements intimately engage each other along an interface. 
     As such, only a portion of a total surface area of the broadside surface  273  is exposed to a corresponding air dielectric  246 , and only a portion of a total surface area of the broadside surface  274  is exposed to a corresponding air dielectric  246 . More specifically, the broadside surface  273  includes an exposed area  282  and a covered area  283 . The broadside surface  274  includes an exposed area  284  and a covered area  285 . The covered areas  283 ,  285  directly engage the dielectric body  210  such that the covered areas  283 ,  285  are covered by the dielectric body  210 . 
     The various dimensions of the signal conductor  212  and the dielectric body  210  may be configured to achieve a target electrical performance. For example, the dimensions of the exposed areas  282 ,  284 ; the dimensions of the covered areas  283 ,  285 ; the dimensions of the interior surfaces  275 ,  276  and  277 ,  278 ; the depths  287 ,  288 ; and the thickness  286  of the signal conductor  212  may be configured to achieve a target electrical performance. More specifically, the dimensions may be configured to accommodate for the skew caused by the different path lengths of the signal conductors  212 ,  214  ( FIG. 4 ). In the illustrated embodiment, the exposed areas  282 ,  284  have substantially identical sizes and shapes, and the covered areas  283 ,  285  have substantially identical sizes and shapes. In alternative embodiments, however, the exposed areas  282 ,  284  and the covered areas  283 ,  285  may have other shapes to achieve the target electrical performance. 
     By way of example only, electrical connectors set forth herein may be configured to have an approximate impedance, such as 100 Ohm or 85 Ohm. The height  256  ( FIG. 6 ) of the flag segment  250  may be two times (2×) the height  262  ( FIG. 6 ) of the signal-control trench  224 . In certain embodiments, the height  256  may be about 1.5× the height  262  or, more specifically, about 1.2× the height  262 . Various values for the dimensions may be used. For example, the height  256  may be between about 1.50 mm to about 0.50 mm. In particular embodiments, the height  256  may be about 0.75 mm to about 0.45 mm or, more specifically, about 0.65 mm to about 0.55 mm. The height  262  may be between about 1.00 mm to about 0.25 mm. In particular embodiments, the height  262  may be about 0.60 mm to about 0.30 mm or, more specifically, about 0.55 mm to about 0.45 mm. The electrical connectors set forth herein may achieve the target electrical performance while having critical dimensions that fall within a normal range of manufacturing tolerances. In other words, the target electrical performance may be achieved despite the manufacturing tolerances. 
     Returning to  FIG. 4 , the dielectric bodies  210  of the pathway assemblies  230 A- 230 C have a total of five (5) signal-control trenches  224 . In some embodiments, the pathway assemblies  230 A- 230 C may have a different number of signal-control trenches  224  with respect to other pathway assemblies. For instance, each of the pathway assemblies  230 A,  230 B has two signal-control trenches  224 , but the pathway assembly  230 C has only a single signal-control trench  224 . Also shown, the signal-control trenches  224  of the different pathway assemblies  230 A- 230 C may have different lengths. For example, the length of the signal-control trench  224  for the pathway assembly  230 C is greater than either of the lengths of the signal-control trenches  224  for the pathway assembly  230 A. 
     The following describes embodiments and/or aspects that are supported by the above description. The following refers to exemplary elements that were described and illustrated with respect to  FIGS. 1-7 . However, it is understood that 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. 
     For example, in one embodiment, an electrical connector (e.g.  152 ) is provided. The electrical connector may include a connector body (e.g.,  158 ) having a mating side (e.g.,  154 ) and a mounting side (e.g.,  156 ) that are configured to engage respective electrical components. The electrical connector may also include a conductor pair (e.g.,  201 A- 201 C) including first and second signal conductors (e.g.,  212 ,  214 ) that extend through the connector body along respective paths between the mating and mounting sides. The first signal conductor has a height and a thickness taken transverse to a direction of the respective path and includes a flag segment (e.g.,  250 ) and a base segment (e.g.,  252 ), wherein the height (e.g.,  256 ) of the first signal conductor along the flag segment is greater than the height (e.g.,  262 ) of the first signal conductor along the base segment. The electrical connector also includes a dielectric body (e.g.,  210 ) extending between the mating and mounting sides and surrounding the conduct or pair. The dielectric body has a signal-control trench (e.g.,  224 ) that extends along and exposes the flag segment to an air dielectric (e.g.,  246 ) within the signal-control trench. The signal-control trench has a height (e.g.,  262 ) that is measured along the height of the flag segment. The height of the signal-control trench is less than the height of the flag segment. 
     In some embodiments, the first signal conductor includes opposite edge surfaces (e.g.,  271 ,  272 ) that extend along the thickness (e.g.,  286 ) of the first signal conductor, and opposite broadside surfaces (e.g.,  273 ,  274 ) that extend along the height of the first signal conductor. The signal-control trench may expose at least one of the broadside surfaces to the air dielectric. Also, the at least one broadside surface (e.g.,  273 ,  274 ) may have an exposed area (e.g.,  282 ) that interfaces with the air dielectric and a covered area (e.g.,  283 ) that is directly engaged to and covered by the dielectric body ( 210 ). 
     As used herein, an element or step recited in the singular and proceeded with the word “a” or “an” should be understood as not excluding plural of said elements or steps, unless such exclusion is explicitly stated. Furthermore, references to “one embodiment” or “an embodiment” are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Moreover, unless explicitly stated to the contrary, embodiments “comprising” or “having” an element or a plurality of elements having a particular property may include additional elements not having that property. 
     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.