Contact module for a connector assembly

A contact module includes a leadframe having signal contacts arranged in pairs. Each signal contact includes a lead having sides extending between inner and outer edges. The contact module includes a dielectric frame supporting the leadframe having a first side and a second side with windows extending through the dielectric frame between the first side and the second side. The windows exposing to air the sides, the inner edges and the outer edges of the corresponding leads along a majority of lengths of the leads. The contact module includes a shield structure having a first ground shield at the first side and a second ground shield at the second side to provide electrical shielding for the signal contacts.

BACKGROUND OF THE INVENTION

The subject matter herein relates generally to connector assemblies.

Some electrical systems utilize connector assemblies, such as header assemblies and receptacle assemblies, to interconnect two circuit boards, such as a motherboard and daughtercard. The connector assemblies include contact modules having contacts terminated to the circuit boards. High speed connector assemblies suffer from problems with cross talk and can exhibit higher than desirable insertion loss due to geometries of the signal contacts and the shield structure for the connector assemblies. For example, gaps or spaces in shielding through the connector assembly can result in reduced connector performance. Additionally, contact modules have problems with electrical skew due to contacts having different lengths. Some known connector assemblies provide conductive holders for each contact module that provides 360° shielding for each pair of signal contacts along the entire lengths of the signal transmission lines. For example, the contact modules include plated plastic shells that hold each leadframe. However, the plated plastic shells are expensive to manufacture.

A need remains for a cost effective and reliable contact module having improved electrical performance.

BRIEF DESCRIPTION OF THE INVENTION

In one embodiment, a contact module for a connector assembly is provided. The contact module includes a leadframe having first signal contacts arranged in pairs. Each first signal contact has a mating end configured to be mated to a mating connector assembly and a mounting end configured to be terminated to a circuit board. Each first signal contact has a first lead extending between the mating end and the mounting end. The first lead has sides extending between an inner edge and an outer edge. The contact module includes a dielectric frame supporting the leadframe. The dielectric frame has a first side and a second side. The dielectric frame has windows extending through the dielectric frame between the first side and the second side. The windows exposing to air the sides, the inner edges and the outer edges of the corresponding first leads along a majority of lengths of the first leads. The contact module includes a shield structure having a first ground shield at the first side and a second ground shield at the second side. The first and second ground shields provide electrical shielding for the first signal contacts.

In another embodiment, a contact module for a connector assembly is provided. The contact module includes a leadframe having first signal contacts arranged in pairs. Each first signal contact has a mating end configured to be mated to a mating connector assembly and a mounting end configured to be terminated to a circuit board. Each first signal contact has a first lead extending between the mating end and the mounting end. The first lead has sides extending between an inner edge and an outer edge. The contact module includes a dielectric frame supporting the leadframe. The dielectric frame has a first side and a second side. The dielectric frame has an inner hub and an outer rail. The dielectric frame has connecting rails extending between the inner hub and the outer rail. The dielectric frame has cross-rails between the connecting rails. The dielectric frame has windows extending through the dielectric frame between the first side and the second side. The windows are bound by corresponding connecting rails and cross-rails. The windows expose the first leads to air. The dielectric frame has first securing posts extending from the inner hub, the outer rail, and the connecting rails. The dielectric frame has first securing posts extending from the inner hub, the outer rail, and the connecting rails. The contact module includes a shield structure having a first ground shield at the first side and a second ground shield at the second side. The first ground shield includes securing post openings receiving first securing posts. The second ground shield includes securing post openings receiving second securing posts. The first and second ground shields provide electrical shielding for the first signal contacts.

In a further embodiment, a connector assembly is provided. The connector assembly includes a housing having a mating end configured to be mated with a mating connector assembly. The housing has a cavity. The connector assembly includes contact modules received in the cavity. The contact modules are configured to be mated with the mating connector assembly. The contact modules are configured to be mounted to a circuit board. Each contact module includes a leadframe having first signal contacts arranged in pairs. Each first signal contact has a mating end configured to be mated to a mating connector assembly and a mounting end configured to be terminated to a circuit board. Each first signal contact has a first lead extending between the mating end and the mounting end. The first lead has sides extending between an inner edge and an outer edge. The contact module includes a dielectric frame supporting the leadframe. The dielectric frame has a first side and a second side. The dielectric frame has an inner hub and an outer rail. The dielectric frame has connecting rails extending between the inner hub and the outer rail. The dielectric frame has cross-rails between the connecting rails. The dielectric frame has windows extending through the dielectric frame between the first side and the second side. The windows are bound by corresponding connecting rails and cross-rails. The windows expose to air the sides, the inner edges and the outer edges of the corresponding first leads along a majority of lengths of the first leads. The dielectric frame has first securing posts extending from the inner hub, the outer rail, and the connecting rails. The dielectric frame has first securing posts extending from the inner hub, the outer rail, and the connecting rails. The contact module includes a shield structure having a first ground shield at the first side and a second ground shield at the second side. The first ground shield includes securing post openings receiving first securing posts. The second ground shield includes securing post openings receiving second securing posts. The first and second ground shields provide electrical shielding for the first signal contacts.

In another embodiment, a contact module is provided for a connector assembly including a first frame assembly and a second frame assembly. The first frame assembly includes a first leadframe and a first dielectric frame, the first leadframe having first signal contacts, each first signal contact having a mating end configured to be mated to a mating connector assembly and a mounting end configured to be terminated to a circuit board, each first signal contact having a first lead extending between the mating end and the mounting end, the first lead having sides extending between an inner edge and an outer edge, the first dielectric frame supporting the first leadframe, the first dielectric frame having an inner side and an outer side, the outer side defining a first side of the contact module, the first dielectric frame having windows extending through the first dielectric frame between the inner side and the outer side, the windows of the first dielectric frame exposing to air the sides, the inner edges and the outer edges of the corresponding first leads along a majority of lengths of the first leads. The second frame assembly includes a second leadframe and a second dielectric frame, the second leadframe having second signal contacts aligned with first signal contacts of the first leadframe in pairs, each second signal contact having a mating end configured to be mated to the mating connector assembly and a mounting end configured to be terminated to the circuit board, each second signal contact having a second lead extending between the mating end and the mounting end, the second lead having sides extending between an inner edge and an outer edge, the second dielectric frame supporting the second leadframe, the second dielectric frame having an inner side and an outer side defining a second side of the contact module, the inner side of the second dielectric frame facing the inner side of the first dielectric frame, the second dielectric frame having windows extending through the second dielectric frame between the inner side and the outer side, the windows of the second dielectric frame exposing to air the sides, the inner edges and the outer edges of the corresponding second leads along a majority of lengths of the second leads, the windows of the second dielectric frame being aligned with and open to the windows of the first dielectric frame. The contact module includes a shield structure having a first ground shield coupled to the first side and a second ground shield coupled to the second side, the first and second ground shields providing electrical shielding for the first and second signal contacts.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1is a perspective view of an exemplary embodiment of an electrical connector system100illustrating a first connector assembly102and a second connector assembly104that may be directly mated together. The first connector assembly102and/or the second connector assembly104may be referred to hereinafter individually as a “connector assembly” or collectively as “connector assemblies”. The first connector assembly102or the second connector assembly104may be a receptacle assembly and the first connector assembly102or the second connector assembly104may be a header assembly. In the description, the first connector assembly102and corresponding components may be referred to as a receptacle assembly or receptacle components and the second connector assembly104and corresponding components may be referred to as a header assembly or header components.

The first and second connector assemblies102,104are each electrically connected to respective circuit boards106,108. The first and second connector assemblies102,104are utilized to electrically connect the circuit boards106,108to one another at a separable mating interface. In an exemplary embodiment, the circuit boards106,108are oriented perpendicular to one another when the first and second connector assemblies102,104are mated. Alternative orientations of the circuit boards106,108are possible in alternative embodiments.

A mating axis110extends through the first and second connector assemblies102,104. The first and second connector assemblies102,104are mated together in a direction parallel to and along the mating axis110.

The first connector assembly102includes a housing120that holds a plurality of contact modules122. Any number of contact modules122may be provided to increase the signal pin count of the first connector assembly102. The contact modules122each include a plurality of signal contacts124(shown inFIG. 2) that are received in the housing120for mating with the second connector assembly104. In an exemplary embodiment, the signal contacts124are arranged in pairs defining differential pairs. In the illustrated embodiment, the pairs of signal contacts124are arranged in columns defining a pair-in-column connector interface. In an exemplary embodiment, each contact module122has a shield structure126for providing electrical shielding for the signal contacts124. In an exemplary embodiment, the shield structure126is electrically connected to the second connector assembly104and/or the circuit board106. For example, the shield structure126may be electrically connected to the second connector assembly104by extensions (e.g. beams or fingers) extending from the contact modules122that engage the second connector assembly104. The shield structure126may be electrically connected to the circuit board106by features, such as ground pins.

The first connector assembly102includes a mating end128and a mounting end130. The signal contacts124are received in the housing120and held therein at the mating end128, such as for mating to the second connector assembly104. In other embodiments, the mating end128may be mated to another component, such as a circuit board. The signal contacts124are arranged in a matrix of rows and columns. In the illustrated embodiment, at the mating end128, the rows are oriented horizontally and the columns are oriented vertically. Other orientations are possible in alternative embodiments. Any number of signal contacts124may be provided in the rows and columns. The signal contacts124also extend to the mounting end130for mounting to an electrical component, such as the circuit board106. In other embodiments, the mounting end130may be mounted to another electrical component, such as an electrical connector. Optionally, the mounting end130may be substantially perpendicular to the mating end128.

The housing120includes a plurality of signal contact openings132and a plurality of ground contact openings134at the mating end128. The signal contacts124are received in corresponding signal contact openings132. Optionally, a single signal contact124is received in each signal contact opening132. The signal contact openings132may also receive corresponding signal contacts144therein when the first and second connector assemblies102,104are mated. The ground contact openings134receive ground shields146therein when the first and second connector assemblies102,104are mated. The ground contact openings134receive grounding beams302(shown inFIG. 2) of the shield structure126of the contact modules122that mate with the ground shields146to electrically common the first and second connector assemblies102,104.

The housing120is manufactured from a dielectric material, such as a plastic material, and provides isolation between the signal contact openings132and the ground contact openings134. The housing120isolates the signal contacts124and the signal contacts144from the ground shields146. The housing120isolates each set of signal contacts124,144from other sets of signal contacts124,144.

The second connector assembly104includes a housing136holding contact modules138. The housing136has walls140defining a chamber142at a mating end150of the second connector assembly104. A mounting end152of the second connector assembly is mounted to an electrical component, such as the circuit board108. In other embodiments, the mounting end152may be mounted to another electrical component, such as an electrical connector. Optionally, the mounting end152may be substantially perpendicular to the mating end150. In the illustrated embodiment, the first connector assembly102is coupled to the mating end150, such as being received in the chamber142through the mating end150. In other embodiments, the mating end150may be mated to another component, such as a circuit board. The housing120engages the walls140to hold the first connector assembly102in the chamber142. The signal contacts144and the ground shields146extend into the chamber142. In an exemplary embodiment, the signal contacts144are arranged as differential pairs. In the illustrated embodiment, the pairs of signal contacts144are arranged in rows defining a pair-in-row connector interface. The ground shields146are positioned between the differential pairs to provide electrical shielding between adjacent differential pairs. In the illustrated embodiment, the ground shields146are C-shaped and provide shielding on three sides of the pair of signal contacts144. Other shapes are possible in alternative embodiments.

FIG. 2is an exploded view of one of the contact modules122and part of the shield structure126. The shield structure126includes a first ground shield202and a second ground shield204. The first and the second ground shields202,204electrically connect the contact module122to the ground shields146(shown inFIG. 1). The first and the second ground shields202,204provide electrical shielding on both sides of the signal contacts124. In an exemplary embodiment, the first and second ground shields202,204are configured to be closely coupled to the signal contacts124to provide electrical shielding between pairs of the signal contacts124without being physically located between the pairs of signal contacts124. The first ground shield202is provided at a first side of the contact module122and the second ground shield204is provided at a second side of the contact module122. In various embodiments, the first ground shield is coupled to the first side of the contact module122and the second ground shield204is coupled to the second side of the contact module122.

The contact module122includes a frame assembly220including a leadframe230and a dielectric frame240. The leadframe230defines the signal contacts124. The leadframe230is a stamped and formed structure. The dielectric frame240surrounds and supports the signal contacts124of the leadframe230. For example, the dielectric frame240may be an overmolded body configured to be overmolded around the leadframe230to form the dielectric frame240. Other manufacturing processes may be utilized to form the contact modules122, such as loading signal contacts124into a formed dielectric body. The signal contacts124are shaped and positioned for enhanced electrical performance at high data speed, such as to reduce cross-talk, reduce insertion loss, reduce skew, match target impedance, and the like. The dielectric frame240is positioned relative to the leadframe230for enhanced electrical performance at high data speeds, such as to reduce cross-talk, reduce insertion loss, reduce effects of skew, achieve target impedance, and the like.

FIG. 3is a side view of a first side of the contact module122in accordance with an exemplary embodiment.FIG. 4is a perspective view of the first side of the contact module122in accordance with an exemplary embodiment.FIG. 5is a side view of a second side of the contact module122in accordance with an exemplary embodiment.FIG. 6is a perspective view of the second side of the contact module122in accordance with an exemplary embodiment.

The dielectric frame240includes frame members holding the signal contacts124. For example, the dielectric frame240includes an inner hub242at a radially inner portion (for example, at the intersection of the front and the bottom) of the dielectric frame240and an outer rail244at a radially outer portion of the dielectric frame240. The dielectric frame240includes a bottom rail245between the inner hub242and the outer rail244. The dielectric frame240includes a front rail246between the inner hub242and the outer rail244. The dielectric frame240includes other frame members extending from the inner hub242and/or the outer rail244and/or the bottom rail245and/or the front rail246and/or other frame members to hold the signal contacts124. For example, the dielectric frame240includes connecting rails247extending between the inner hub242and the outer rail244and cross-rails248extending between the connecting rails247or between the bottom rail245and the connecting rail247or between the front rail246and the connecting rail247. The dielectric frame240includes closing rails249completely filling spaces between other rails or frame members. For example, the closing rails249may be located at or near the inner hub242. In an exemplary embodiment, the frame members encase portions or segments of the signal contacts124and the dielectric frame240includes openings that exposes portions or segments of the signal contacts124.

The signal contacts124have mating portions250extending forward from the front rail246and mounting portions252extending from the bottom rail245. The signal contacts124include leads254extending between the mating portions250and the mounting portions252. The leads254extend along generally parallel paths or segments through the frame assembly220between the mating portions250and the mounting portions252. The mating portions250extend from the dielectric frame240for mating with the second connector assembly104(shown inFIG. 1). The mounting portions252extend from the dielectric frame240for mounting to the circuit board106(shown inFIG. 1). For example, the mounting portions252may be compliant pins, such as eye-of-the-needle pins. Other types of mounting portions252may be provided in alternative embodiments, such as solder tails, spring beams, and the like. In an exemplary embodiment, the mating portions250extend generally perpendicular with respect to the mounting portions252. Each of the lead254includes opposite sides232,234and an inner edge246opposite an outer edge238(shown inFIGS. 4 and 6).

In an exemplary embodiment, the leads254have different lengths between the mating portions250and the mounting portions252. For example, the leads254located at or near the inner hub242are relatively shorter and the leads254located at or near the outer rail244are relatively longer. In an exemplary embodiment, for increased electrical performance of the signal transmission lines of the contact module122, the dielectric frame240includes compensation features to compensate for the different lengths of the leads254. For example, the dielectric frame240includes windows260used to expose corresponding leads254to air and trenches262used to expose corresponding leads254to air. Optionally, the dielectric frame240may include pinch point openings264in the inner hub242, the closing rail249, or other frame members formed at pinch point used to hold the leads254during overmolding of the dielectric frame240. The pinch point openings264are smaller than the windows260and the trenches262and expose small areas of the leads254to air.

In various embodiments, the number of windows260and the lengths of the windows260may be different for different leads254. The windows260expose both of the leads254within a pair (within the same window260). In an exemplary embodiment, the leads254include pads256and bridges258(shown in phantom, also shown inFIG. 2) between the pads256. The pads256are wider than the bridges258. The pads256are located along portions of the leads254exposed within the windows260. The bridges258are provided along portions of the leads254that extend through the frame members, such as the bottom rail245, the front rail246, the connecting rail247, the closing rail249and the inner hub242. The pads256are wider to control impedance due to the lower relative dielectric constant of air compared to plastic. The bridges258are narrower to provide compensation along the signal transmission lines where the leads254pass through the plastic material of the dielectric frame240as opposed to the air in the windows260.

In an exemplary embodiment, the leads254may be arranged in different groups or sets based on the lengths of the leads254. For example, the leads254may be grouped in three sets, with a first set of the leads254being the longest length leads (from mounting end to mating end), a second set of the leads254being of intermediate length, and a third set of the leads254having the shortest lead length. The first set includes first signal contacts124ahaving first leads254a. The second set includes second signal contacts124bhaving second leads254b. The third set includes a third signal contacts124chaving third leads254c. The first signal contacts124aare arranged in pairs with the first leads254aof each pair including a longer first lead254dand a shorter first lead254e. Similarly, the second leads254bare arranged in pairs each including a longer second lead254fand a shorter second lead254gand the third leads254care arranged in pairs each including a longer third lead254hand a shorter third lead254i. In the illustrated embodiment, the outer most three pairs are in the first set, the innermost two pairs are in the third set, and the intermediate three pairs are in the second set; however the sets may include greater or fewer pairs in alternative embodiments.

The windows260extend through the dielectric frame240between the frame members. The windows260are bounded by corresponding frame members, such as the bottom rail245, the front rail246, the connecting rail247, the cross-rail248, the closing rail249and the inner hub242. The frame members provide structural rigidity for the contact module122, such as to allow the contact module122to be mounted to the circuit board106. The cross-rails248provides support for the connecting rails247. The leads254pass through the bottom rail245, the connecting rails247, the front rail246, the closing rail249and the inner hub242. The cross-rails248generally extend along the leads254but the leads254are not received in the cross-rails248.

In an exemplary embodiment, the dielectric frame240includes locating tabs266extending from the cross rails248into the windows260. The locating tabs266are configured to locate and support the leads254. The locating tabs266are configured to engage the leads254to support the leads254. For example, the locating tabs266may include slots or grooves267that receive the leads254to locate the leads254relative to the dielectric frame240. The locating tabs266may support side to side positioning of the leads254. The locating tabs266may control positioning of the leads254within the windows260, such as to support the leads254spaced apart from the cross rails248. In an exemplary embodiment, the leads254are completely surrounded by air within the windows260(for example, both sides232,234and both inner and outer edges236,238are surrounded by air). In an exemplary embodiment, the leads254include notches268along edges of the leads254opposite the locating tabs266. The leads254are narrower between the inner and outer edges at the notches268. The notches268are compensation features that compensate for portions of the leads254passing through the locating tabs266. For example, because portions of the leads254at the locating tabs266are surrounded by the plastic material of the dielectric frame240, the notches268reduce the width of the leads254at the area of the locating tab266to maintain signal integrity along the signal transmission lines.

In an exemplary embodiment, the windows260extend entirely through the dielectric frame240. The windows260extend along portions or segments of the leads254between the mating portions250and the mounting portions252. In an exemplary embodiment, the windows260extend along a majority of the length of the corresponding leads254. In an exemplary embodiment, the windows260have different lengths. For example, the windows260closer to the outer rail244are longer than the windows260closer to the inner hub242. The longer windows260expose greater lengths of the leads254than the shorter windows260. In an exemplary embodiment, the longer windows260are provided along the first leads254aand the shorter windows260are provided along the second leads254b, while the dielectric frame240does not include any windows260along the third leads254c. Rather, the third leads254cinclude trenches262along the longer third leads254hand no trenches262along the shorter third leads254i. In an exemplary embodiment, a greater number of windows260are provided along the first leads254a(for example, four windows260) as compared to the number of windows260provided along the second leads254b(for example, three windows260) and the third leads254c(for example, zero windows260). The number and lengths of the windows260and the trenches262provide electrical compensation for the signal transmission lines, such as to reduce cross-talk, reduce insertion loss, reduce skew, match target impedance, and the like.

In an exemplary embodiment, each of the windows260may be stepped such that the windows260are wider along the radially outer edge of the window260and narrower at the radially inner edge of the window260. For example, the windows260may include steps269at one or both ends of the windows260. The steps269are compensation features to improve signal integrity of the contact module122, such as to compensate for skew. The steps269covers the shorter leads254(for example, the shorter first lead254e) to allow the windows260to be open along longer portions of the longer leads254(for example, the longer first lead254d). The windows260are stepped to expose longer lengths of the longer first leads254dto air than the lengths of the shorter first leads254e. In the illustrated embodiment, the steps269are provided along one of the connecting rails247; however, the steps269may be provided along the other frame members in alternative embodiments.

In an exemplary embodiment, the dielectric frame240includes a first side270(FIGS. 3 and 4) and a second side272(FIGS. 5 and 6) opposite the first side270. The dielectric frame240includes a front274and a rear276opposite the front274. The dielectric frame240includes a top278and a bottom280opposite the top278. The front rail246is provided at the front274. The bottom rail245is provided at the bottom280. The outer rail244extends along the rear276and the top278. The inner hub242is located generally at the intersection between the front274and the bottom280. The first ground shield202(FIG. 2) is coupled to the first side270and the second ground shield204(FIG. 2) is coupled to the second side272.

In an exemplary embodiment, the dielectric frame240includes a first pocket282(FIGS. 3 and 4) at the first side270and a second pocket284(FIGS. 5 and 6) at the second side272. The first pocket282receives the first ground shield202(FIG. 2) and the second pocket284receives the second ground shield204(FIG. 2). The dielectric frame240has a first thickness286between the first and second sides270,272, such as along the outer rail244. The dielectric frame240has a second thickness288at the first and second pockets282,284. For example, the bottom rail245, the front rail246, the connecting rails247, the cross rails248, the closing rail249and the inner hub242have the second thickness288.

In an exemplary embodiment, the dielectric frame240includes securing posts290extending into the first pocket282and the second pocket284. The securing posts290extend from corresponding frame members, such as the bottom rail245, the front rail246, the connecting rails247, the cross rails248, the closing rail249and/or the inner hub242. The securing posts290in the first pocket282secure the first ground shield202to the dielectric frame240. The securing posts290and the second pocket284secure the second ground shield204to the dielectric frame240. In various embodiments, the securing posts290may be heat stakes. In an exemplary embodiment, the securing posts290are shaped to pull the first and second ground shields202,204inward into the first and second pockets282,284against the dielectric frame240. The securing posts290pull the first and second ground shields202,204inward toward the leadframe230.

In an exemplary embodiment, the dielectric frame240includes locating posts292extending across the first and second pockets282,284to distal ends294of the locating posts292. The locating posts292extend from corresponding frame members, such as the bottom rail245, the front rail246, the connecting rails247, the cross rails248, the closing rail249and/or the inner hub242. The distal ends294are configured to engage the locating posts of an adjacent contact module122to locate the contact module122relative to the adjacent contact module122. In various embodiments, the distal ends294of the locating posts292are coplanar with the first and second sides270,272of the dielectric frame240.

Returning toFIG. 2, the first and second ground shields202,204are configured to be coupled to the frame assembly220. The first ground shield202includes a main body300. In the illustrated embodiment, the main body300is generally planar. In an exemplary embodiment, the first ground shield202is manufactured from a metal material. For example, the metal material may be phosphor-bronze, brass, copper, silver, aluminum, platinum and the like or a combination thereof. In an exemplary embodiment, the first ground shield202may be stamped and formed. The first ground shield202includes grounding beams302extending forward from a front304of the main body300such that the grounding beams302may be loaded into the housing120(shown inFIG. 1). The first ground shield202includes a plurality of ground pins306extending from a bottom308of the first ground shield202. The ground pins306are configured to be terminated to the circuit board106(shown inFIG. 1). The ground pins306may be compliant pins, such as eye-of-the-needle pins, that are press-fit into plated vias in the circuit board106. Other types of termination means or features may be provided in alternative embodiments to couple the first ground shield202to the circuit board106.

The second ground shield204includes a main body310. In the illustrated embodiment, the main body310is generally planar. The second ground shield204includes grounding beams312extending forward from a front314of the main body310such that the grounding beams312may be loaded into the housing120(shown inFIG. 1). The second ground shield204includes a plurality of ground pins316extending from a bottom318of the second ground shield204. The ground pins316are configured to be terminated to the circuit board106.

In an exemplary embodiment, the first ground shield202includes securing posts openings320configured to receive corresponding securing posts290extending into the first pocket282at the first side270of the dielectric frame240. The securing posts290extend through the securing posts openings320and are configured to be secured to the first ground shield202. Optionally, the securing posts290may be heat staked or riveted to the first ground shield202to secure the first ground shield202and the first pocket282. In various embodiments, the securing posts290may be coupled to the first ground shield202by ultrasonic welding. In an exemplary embodiment, the first ground shield202includes locating post openings322configured to receive corresponding locating posts292extending into the first pocket282at the first side270of the dielectric frame240. The distal ends294of the locating posts292may extend beyond the first ground shield202, such as to engage corresponding locating posts292of the adjacent contact module122.

In an exemplary embodiment, the second ground shield204includes securing posts openings330configured to receive corresponding securing posts290extending into the second pocket284at the second side272of the dielectric frame240. The securing posts290extend through the securing posts openings330and are configured to be secured to the second ground shield204. Optionally, the securing posts290may be heat staked or riveted to the second ground shield204to secure the second ground shield204and the second pocket284. In various embodiments, the securing posts290may be coupled to the second ground shield204by ultrasonic welding. In an exemplary embodiment, the second ground shield204includes locating post openings332configured to receive corresponding locating posts292extending into the second pocket284at the second side272of the dielectric frame240. The distal ends294of the locating posts292may extend beyond the second ground shield204, such as to engage corresponding locating posts292of the adjacent contact module122.

FIG. 7is a perspective view of the contact module122showing the first and second ground shields202,204coupled to the dielectric frame240.FIG. 8is a side view of the contact module122in an assembled state. The first and second ground shields202,204are received in the first and second pockets282,284, respectively, of the dielectric frame240. The securing posts290secure the ground shields202,204to the dielectric frame240. In an exemplary embodiment, multiple securing posts290are provided along the bodies300,310of the ground shields202,204to hold the bodies300,310of the ground shields202,204tightly against the frame members of the dielectric frame240. The locating posts292extend through the ground shields202,204for positioning the contact module122relative to adjacent contact modules122.

FIG. 9is a cross-sectional view of a portion of the contact module122showing the first and second ground shields202,204coupled to the dielectric frame240.FIG. 10is an enlarged, cross-sectional view of a portion of the contact module122showing the shield structure126of the contact module122relative to a single pair of the signal contacts124. The first and second ground shields202,204are received in the first and second pockets282,284, respectively, of the dielectric frame240. The securing posts290are coupled to the ground shields202,204to pull the ground shields202,204inward toward the leadframe230. As such, air gaps between the ground shields202,204and the dielectric frame240are eliminated. The bodies300,310are parallel to each other and form a ground shield gap340between the first and second ground shields202,204. The leadframe230is received in the ground shield gap340.

In an exemplary embodiment, the leadframe230may be centered between the first and second ground shields202,204and the ground shield gap340. For example, a first spacing342between the leads254and the first ground shield202may be equal to a second spacing344between the leads254and the second ground shield204. The first spacing342and the second spacing344may be tightly controlled and maintained along the entire leadframe plane. The pairs of signal contacts124are separated by pair gaps346. The ground shields202,204provide electrical shielding across the pair gaps346. In an exemplary embodiment, the ground shields202,204provide electrical shielding across the pair gaps346without the first and second ground shields202,204being physically located in the pair gap346. For example, the ground shields202,204do not include stamped and formed beams or tabs that are bent across the contact module122into the pair gap346. Additional ground features, such as ground tabs and ground skewers are not provided between the first and second ground shields202,204across the pair gap346. In an exemplary embodiment, the spacing342,344between the leads254and the ground shields202,204is relatively small such that the signal contacts124are closely coupled to the ground shields202,204. The thickness of the dielectric frame240at the frame members is relatively thin to closely position the ground shields202,204relative to the signal contacts124. For example, the signal contacts124are more closely coupled to the ground shields202,204than to adjacent pairs of signal contacts124, thus mitigating crosstalk between the pairs of signal contacts124.

FIG. 11is an exploded view of a second connector assembly104of the electrical connector system100in accordance with an exemplary embodiment. The second connector assembly104includes the housing136holding a plurality of the contact modules138. In an exemplary embodiment, the second connector assembly104includes a contact module holder154configured to hold each of the contact modules138. The second connector assembly104includes a contact pin organizer156holding pins or tails of the signal contacts144and the ground contacts for mounting to the circuit board. The second connector assembly104includes the signal contacts144arranged as differential pairs. The signal contacts144are arranged in rows defining pair-in-row contact modules. The second connector assembly104includes a shield structure158providing electrical shielding for the signal contacts144. The ground shields146form part of the shield structure158and provide electrical shielding between adjacent differential pairs. In the illustrated embodiment, the second connector assembly104includes ground bus bars148forming parts of the shield structure158and the ground shields146.

FIG. 12is an exploded view of the contact module138in accordance with an exemplary embodiment.FIG. 13is a side view of a first side of the contact module138in accordance with an exemplary embodiment.FIG. 14is a side perspective view of a second side of the contact module138in accordance with an exemplary embodiment.

The shield structure158includes a first ground shield502(FIG. 12) and a second ground shield504(FIG. 12). The first and the second ground shields502,504electrically connect the contact module138to the first connector assembly102(shown inFIG. 1). The first and the second ground shields502,504provide electrical shielding on both sides of the signal contacts144. In an exemplary embodiment, the first and second ground shields502,504are configured to be closely coupled to the signal contacts144to provide electrical shielding between pairs of the signal contacts144without being physically located between the pairs of signal contacts144. The first ground shield502is provided at a first side of the contact module122and the second ground shield504is provided at a second side of the contact module122. In various embodiments, the first ground shield502is coupled to the first side of the contact module122and the second ground shield504is coupled to the second side of the contact module122.

The contact module138includes first and second frame assemblies520,521. The first frame assembly520includes a first leadframe530and a first dielectric frame540. The second frame assembly521includes a second leadframe531and a second dielectric frame541. The frame assemblies520,521are arranged side-by-side to form the contact module138. The leadframes530,531define the signal contacts144. The leadframes530,531are stamped and formed structures. The dielectric frames540,541surround and support the signal contacts144of the leadframes530,531, respectively. For example, the dielectric frames540,541may be overmolded bodies configured to be overmolded around the leadframes530,531. Other manufacturing processes may be utilized. The signal contacts144are shaped and positioned for enhanced electrical performance at high data speed, such as to reduce cross-talk, reduce insertion loss, reduce skew, match target impedance, and the like. In an exemplary embodiment, the signal contacts144of the first frame assembly520are arranged side-by-side with the signal contacts144of the second frame assembly521to form differential pairs of signal contacts. The pairs are arranged in rows. The dielectric frames540,541are positioned relative to the leadframes530,531for enhanced electrical performance at high data speeds, such as to reduce cross-talk, reduce insertion loss, reduce effects of skew, achieve target impedance, and the like.

The dielectric frames540,541may be similar to each other and may include similar features. In an exemplary embodiment, the dielectric frames540,541include frame members holding the signal contacts144. For example, the dielectric frames540,541each include an inner hub542at a radially inner portion (for example, at the intersection of the front and the bottom) of the dielectric frame540,541and an outer rail544at a radially outer portion of the dielectric frame540,541. The dielectric frames540,541each include a bottom rail545between the inner hub542and the outer rail544. The dielectric frames540,541each includes a front rail546between the inner hub542and the outer rail544. The dielectric frames540,541may include other frame members extending from the inner hub542and/or the outer rail544and/or the bottom rail545and/or the front rail546and/or other frame members to hold the signal contacts144. For example, the dielectric frames540,541may each include connecting rails547extending between the inner hub542and the outer rail544and cross-rails548extending between the connecting rails547or between the bottom rail545and the connecting rail547or between the front rail546and the connecting rail547. The dielectric frames540,541may include closing rails (not shown) completely filling spaces between other rails or frame members. For example, the closing rails may be located at or near the inner hub542. In an exemplary embodiment, the frame members encase portions or segments of the signal contacts144and the dielectric frames540,541include openings that expose portions or segments of the signal contacts144.

The signal contacts144have mating portions550configured to extend forward from the front rail546and mounting portions552configured to extend from the bottom rail545. The signal contacts144include leads554extending between the mating portions550and the mounting portions552. The mating portions550extend from the dielectric frames540,541for mating with the first connector assembly102(shown inFIG. 1). The mounting portions552extend from the dielectric frames540,541for mounting to the circuit board108(shown inFIG. 1). Each of the lead554includes opposite sides532,534and an inner edge536opposite an outer edge538. The signal contacts144are arranged in pairs with a first signal contact in each pair being held by the dielectric frame540and a second signal contact in each pair being held by the dielectric frame541. The signal contacts144are parallel to each other through the contact module138.

The dielectric frames540,541includes windows560used to expose corresponding leads554to air. In an exemplary embodiment, the windows560in the first dielectric frame540are aligned with and open to the windows560in the second dielectric frame542. In various embodiments, the number of windows560and the lengths of the windows560may be different for different leads554.

In an exemplary embodiment, the leads554include pads556and bridges558between the pads556. The pads556are wider than the bridges558. The pads556are located along portions of the leads554exposed within the windows560. The bridges558are provided along portions of the leads554that extend through the frame members, such as the bottom rail545, the front rail546, the connecting rail547, the closing rail and the inner hub542. The pads556are wider to control impedance due to the lower relative dielectric constant of air compared to plastic. The bridges558are narrower to provide compensation along the signal transmission lines where the leads554pass through the plastic material of the dielectric frames540,541as opposed to the air in the windows560.

The windows560extend through the dielectric frames540,541between the frame members. The windows560are bounded by corresponding frame members, such as the bottom rail545, the front rail546, the connecting rail547, the cross-rail548, the closing rail and the inner hub542. The frame members provide structural rigidity for the contact module138, such as to allow the contact module138to be mounted to the circuit board406. The cross-rails548provide support for the connecting rails547. The leads554pass through the bottom rail545, the connecting rails547, the front rail546, the closing rail and the inner hub542. The cross-rails548generally extend along the leads554but the leads554are not received in the cross-rails548.

In an exemplary embodiment, the dielectric frames540,541include locating tabs566extending from the cross rails548into the windows560. The locating tabs566are configured to locate and support the leads554. The locating tabs566are configured to engage the leads554to support the leads554. The locating tabs566may support side to side positioning of the leads554. The locating tabs566may control positioning of the leads554within the windows560, such as to support the leads554spaced apart from the cross rails548. In an exemplary embodiment, the leads554are completely surrounded by air within the windows560(for example, both sides532,534and both inner and outer edges536,538are surrounded by air).

In an exemplary embodiment, the windows560extend entirely through the dielectric frames540,541. The windows560extend along portions or segments of the leads554between the mating portions550and the mounting portions552. In an exemplary embodiment, the windows560extend along a majority of the length of the corresponding leads554. In an exemplary embodiment, the windows560have different lengths. For example, the windows560closer to the outer rail544are longer than the windows560closer to the inner hub542. The longer windows560expose greater lengths of the leads554than the shorter windows560.

In an exemplary embodiment, the dielectric frames540,541include inner sides facing each other and outer sides facing away from each other. The inner sides abut against each other. The outer side of the first dielectric frame540defines a first side570of the contact module138and the outer side of the second dielectric frame541defines a second side572of the contact module138. The dielectric frames540,541each include a front574and a rear576opposite the front574. The dielectric frames540,541each include a top578and a bottom580opposite the top578. The front rails546are provided at the front574. The bottom rails545are provided at the bottom580. The outer rails544extend along the rear576and the top578. The inner hubs542are located generally at the intersection between the front574and the bottom580. The first ground shield502is provided at a first side of the first dielectric module540and the second ground shield504is provided at a second side of the first dielectric module540, and similarly, the first ground shield502is provided at a first side of the second dielectric module541and the second ground shield504is provided at a second side of the second dielectric module541. For example, the first ground shield502is configured to be coupled to the first side570of the first dielectric frame540and the second ground shield504is configured to be coupled to the second side572of the second dielectric frame541.

In an exemplary embodiment, the dielectric frame540includes a first pocket582at the first side570and the dielectric frame541includes a second pocket584at the second side572. The first pocket582receives the first ground shield502and the second pocket584receives the second ground shield504.

In an exemplary embodiment, the dielectric frames540,541includes securing posts590extending into the pockets582,584. The securing posts590extend from corresponding frame members, such as the bottom rail545, the front rail546, the connecting rails547, the cross rails548, the closing rail and/or the inner hub542. The securing posts590in the first pocket582secure the first ground shield502to the dielectric frame540. The securing posts590in the second pocket584secure the second ground shield504to the dielectric frame541. In various embodiments, the securing posts590may be heat stakes. In an exemplary embodiment, the securing posts590are shaped to pull the first and second ground shields502,504inward into the first and second pockets582,584against the dielectric frames540,541. The securing posts590pull the first and second ground shields502,504inward toward the leadframe530. In various embodiments, the securing posts590may be coupled to the ground shields502,504by ultrasonic welding.

In an exemplary embodiment, the dielectric frames540,541includes locating posts592extending to distal ends594. The locating posts592extend from corresponding frame members, such as the bottom rail545, the front rail546, the connecting rails547, the cross rails548, the closing rail and/or the inner hub542. The distal ends594are configured to engage the locating posts of an adjacent contact module138to locate the contact module138relative to the adjacent contact module138.

With reference toFIG. 12, the first and second ground shields502,504are configured to be coupled to the frame assemblies520,521. The first ground shield502includes a main body600. In an exemplary embodiment, the first ground shield502may be stamped and formed. The first ground shield502includes grounding beams602extending forward from a front604of the main body600. The first ground shield502includes a plurality of ground pins606extending from a bottom608of the first ground shield502. The ground pins606are configured to be terminated to the circuit board106(shown inFIG. 1).

The second ground shield504includes a main body610. In the illustrated embodiment, the main body610is generally planar. The second ground shield504includes grounding beams612extending forward from a front614of the main body610. The second ground shield504includes a plurality of ground pins616extending from a bottom618of the second ground shield504. The ground pins616are configured to be terminated to the circuit board106.

In an exemplary embodiment, the first ground shield502includes securing posts openings620configured to receive corresponding securing posts590extending into the first pocket582at the first side570of the dielectric frame540. The securing posts590extend through the securing posts openings620and are configured to be secured to the first ground shield502. In an exemplary embodiment, the first ground shield502includes locating post openings622configured to receive corresponding locating posts592extending into the first pocket582at the first side570of the dielectric frame540.

In an exemplary embodiment, the second ground shield504includes securing posts openings630configured to receive corresponding securing posts590extending into the second pocket584at the second side572of the dielectric frame540. The securing posts590extend through the securing posts openings630and are configured to be secured to the second ground shield504. In an exemplary embodiment, the second ground shield504includes locating post openings632configured to receive corresponding locating posts592extending into the second pocket584at the second side572of the dielectric frame540.

FIG. 15is a cross-sectional view of a portion of the contact module138showing the first and second ground shields502,504coupled to the dielectric frame540. The first and second ground shields502,504are received in the first and second pockets582,584of the dielectric frames540,541. The securing posts590are coupled to the ground shields502,504to pull the ground shields502,504inward toward the leadframes530,531. As such, air gaps between the ground shields502,504and the dielectric frames540,541are eliminated. In various embodiments, the securing posts590may be coupled to the ground shields502,504by ultrasonic welding. The bodies600,610are parallel to each other and form a ground shield gap640between the first and second ground shields502,504. The leadframes530,531are received in the ground shield gap640. The spacing between the leadframes530,531and the ground shields502,504may be tightly controlled and maintained along the leadframe planes. The leads554of the first leadframe530are spaced from the first ground shield502by a first spacing652and the leads554of the second leadframe531are spaced from the second ground shield504by a second spacing654. The first spacing652may be equal to the second spacing654. The first spacing652and the second spacing654may be tightly controlled and maintained along the entire leadframe plane. In various embodiments, securing posts may pull the dielectric frames540,541together when assembled to tightly control the air gap or spacing between the dielectric frames540,541.

Each pair of signal contacts144is located between the ground shields502,504. The pairs of signal contacts144are separated by pair gaps646. The ground shields502,504provide electrical shielding across the pair gaps646. In an exemplary embodiment, the ground shields502,504provide electrical shielding across the pair gaps646without the first and second ground shields502,504being physically located in the pair gaps646. For example, the ground shields502,504do not include stamped and formed beams or tabs that are bent across the contact module138into the pair gap646. Additional ground features, such as ground tabs are ground skewers are not provided between the first and second ground shields502,504across the pair gap646. In an exemplary embodiment, the spacing between the leads554and the ground shields502,504is relatively small such that the signal contacts144are closely coupled to the ground shields502,504. The thicknesses of the dielectric frames540,541are relatively thin to closely position the ground shields502,504relative to the signal contacts144. For example, the signal contacts144are more closely coupled to the ground shields502,504than to adjacent pairs of signal contacts144, thus mitigating crosstalk between the pairs of signal contacts144.