WO2012027679A2

WO2012027679A2 - High data-rate connector

Info

Publication number: WO2012027679A2
Application number: PCT/US2011/049365
Authority: WO
Inventors: Kent E. Regnier
Original assignee: Molex Incorporated
Priority date: 2010-08-26
Filing date: 2011-08-26
Publication date: 2012-03-01
Also published as: WO2012027679A3

Abstract

A connector system can include a SFP style receptacle that is configured with a first set of terminals that are compatible with an existing SFP solution. The receptacle includes a second set of terminals that are configured to enable communication at higher data rates. A module can be provided that includes a modified edge card that can engage both sets of terminals. Alternatively, a conventional SFP module will only engage the first set of terminals.

Description

High Data-Rate Connector

BACKGROUND OF THE INVENTION

RELATED APPLICATIONS

[001] This application claims priority to Provisional Application No. 61/377,346, filed August 26, 2010, which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

[002] The present invention relates to the field of connectors, more specifically to the field of input/output (I/O) connectors.

DESCRIPTION OF RELATED ART

[003] Small form factor pluggable (SFP) connectors have become widely used. Initially intended to provide a IX connector (one transmit channel and one receive channel) at 2 Gbps, subsequent improvements in the connector and the underlying chip technology have allowed for SFP+ connectors to operate at 10 Gbps. Given the limitations of memory storage, this has tended to be sufficient for a number of applications.

[004] Recent improvements (such as the introduction of solid state drives) and increases in data rates for even long-haul applications has begun to make it possible to consider using even higher data rates. For example, certain industry groups have begun to develop a standard that would provide 25 Gbps channels in 4x and 12x connectors. The technology needed to enable such connectors could also be used in a IX connector. However, a large number of applications do not require further increases in data rates and there is therefore a substantial question as to whether it is worth the expense to upgrade the entire channel. For example, a connector that could offer additional data channels (which could be used or left unused depending on the application) would be useful for certain applications. Consequentially, certain individuals would appreciate a connector solution that offers greater flexibility without the need to upgrade the entire data channel.

BRIEF SUMMARY OF THE INVENTION

[005] A connector system is provided that offers a receptacle that is configured with a first set of terminals that are compatible with an existing solution. The receptacle includes a second set of terminals that are configured to enable communication at higher data rates. A module can be provided that includes a modified edge card that can engage both sets of terminals. Alternatively, a conventional module will only engage the first set of terminals.

BRIEF DESCRIPTION OF THE DRAWINGS

[006] The present invention is illustrated by way of example and not limited in the accompanying figures in which like reference numerals indicate similar elements and in which:

[007] Figure 1 illustrates a perspective view of an embodiment of a connector system.

[008] Figure 2 illustrates a perspective view the connector system of Figure 1 in a partially assembled state.

[009] Figure 3 illustrates an exploded perspective view of an embodiment of a receptacle.

[010] Figure 4 illustrates a perspective view of a housing assembly suitable for use with the receptacle depicted in Figure 3.

[011] Figure 5 illustrates a partially exploded perspective view of housing assembly depicted in Figure 4.

[012] Figure 6 illustrates a perspective view of a plurality of wafers depicted in Figure 5. [013] Figure 7 illustrates a partially exploded perspective view of wafers depicted in Figure 6.

[014] Figure 8 A illustrates a front view of a section taken along the line 5-5 in Figure 4.

[015] Figure 8B illustrates a perspective view of the section depicted in Figure 8A.

[016] Figure 9 illustrates a perspective simplified view of a plug connector engaging terminals.

[017] Figure 9A illustrate a schematic representation of a cross-section of an embodiment of a cable.

[018] Figure 10 illustrates a perspective view of a cross-section of an embodiment of mated connector assembly.

[019] Figure 11 illustrates a perspective enlarged view of embodiment depicted in Figure 10.

[020] Figure 12 illustrates another perspective view of the embodiment depicted in Figure 10.

[021] Figure 13 illustrates an enlarged perspective view of the embodiment depicted in Figure 12.

[022] Figure 14 illustrates a perspective view of a simplified embodiment of a plug connector.

[023] Figure 15 illustrates a perspective view of a portion of an edge card suitable for use in a plug connector.

[024] Figure 16 illustrates another perspective view of the edge card depicted in Figure 15. [025] Figure 17 illustrates a perspective view of a section of an embodiment of a housing assembly.

[026] Figure 18 illustrates a perspective view of an embodiment of a wafer assembly.

[027] Figure 19 illustrates a side view of the embodiment depicted in Figure 18.

[028] Figure 20 illustrates a partial enlarged perspective view of the embodiment depicted in Figure 18.

DETAILED DESCRIPTION OF THE INVENTION

[029] The detailed description that follows describes exemplary embodiments and is not intended to be limited to the expressly disclosed combination(s). Therefore, unless otherwise noted, features disclosed herein may be combined together to form additional combinations that were not otherwise shown for purposes of brevity.

[030] Figures 1-20 illustrates a connector assembly 10 that includes a receptacle 100 (in a stacked configuration) and an SFP style module 50 that can be plugged into the receptacle 100. As can be appreciated, in the depicted stacked configuration, two modules 50 can be plugged into the receptacle 100 in a belly to belly configuration because the receptacle 100 includes an upper port 100a and a lower port 100b. However, it should be noted that a receptacle can include a single port, two ports in a ganged or stacked configuration, or more than two ports in a stacked and ganged configuration such as a 2 x 8 port configuration depicted.

[031] The receptacle 100 includes a cage 101 supports a bezel 30 and is configured to be mounted on a circuit board 20. The cage 101 includes an upper portion 102, a lower portion 103, a rear portion 106, divider walls 104 and center portions 105. The bezel includes a support member 33, a seal 32 and a front cover 31. However, the cage and bezel construction can vary as desired, depending on the desired configuration of the shield, the environment the connector is intended to be positioned in, and the number of ports desired. [032] The cage 101 extends around a connector 110 that includes a housing 112 with a first connecting portion 115 that supports a first card slot 115a and a second connecting portion 116 that supports a second card slot 116a. The card slots each have a front face 113. The housing 112 may include one or more orientation projections 117 that help align the connector 110 with a support circuit board. To help minimize EMI issues, a shield plate 107 can be placed on a front side 114 of the housing 112 so as to help minimize radiation emitting from the terminals positioned in the housing 112.

[033] As can be appreciated from Figure 5, the housing 112 supports a wafer set 120 that includes a plurality of wafers and each wafer is configured to include terminals to support at least one card slot and as depicted, includes terminals to support two card slots. Specifically, the wafer set 120 includes a first wafer pair 122a, a second wafer pair 122b and a third wafer pair 122c. In between each wafer pair is a ground wafer 124. Thus, the depicted configuration provides for a ground, signal, signal wafer pattern that repeats. In an embodiment, the first wafer pair 122a can support terminal pair SP1 and SP2' while the third wafer pair 122c supports terminal pair SP2 and SP1 '. Such a system is suitable for use as an SFP or SFP+ type application because in a standard SFP-type configuration, just two high data rate pairs are utilized. Thus, while two terminals rows 130a, 131a are supported in the first card slot and two terminals rows 130b, 131b are supported in the second card slot (as is standard in an SFP-style application), convention SFP style connectors support just two high data rate channels, the remainder of the terminals being utilized for other functions. It should be noted, however, that in alternative embodiments (not shown for purposes of brevity) there could be three or more wafer groups Gl and if desired, two wafer groups could share a ground wafer.

[034] As depicted, wafer group Gl includes (going from left to right) the ground wafer 124, two signal wafers 126 and another ground wafer 124. The left-most ground wafer supports a ground terminal 142 that is configured to engage a pad on first side of an edge card and also supports a terminal 181 that is configured to engage a pad on an opposing second side of the edge card. Similarly, the signal wafers 126 each include a terminal 141 that is configured to engage pad on one side of a mating edge card while also supporting a terminal 181. In a typical SFP style application, terminals 142, 141, 141 and 142 are configured to provide a ground, signal, signal, ground arrangement that provides a high data rate capable channel. Similarly, terminals 152, 151, 151, 152 (from left to right) provide another high data rate capable channel.

[035] In addition to the convention terminals, the wafers also support terminals 161-164 and terminals 171-174. These terminals 161-164, 171-174 are configured so as to extend only partially toward a front of the card slots and thus have contacts that do not engage a standard SFP module. However, these terminals are configured to provide a high data rate capable channel that is substantially equal or greater than the data rate provided by the conventional high data rate capable channels.

[036] As can be appreciated from Figure 8A, the contact 171a is offset so as to be positioned between the contact 142a and contact 181a. In addition, as depicted in Figure 8B, the terminal 171 is a blanked and formed terminal rather than a conventional blanked terminal as is used for terminals 142 or 181. While the terminals 142 and 181 are positioned in terminal channels 119a and 119b, respectively, the terminal 171 is cantilevered above the dielectric material (essentially in an open area). Therefore, to ensure adequate performance it has been determined beneficial to have the body of the terminal in the open area somewhat wider and closer to adjacent terminals so as to selectively control coupling between terminals in the row. It should be noted that if the above noted offset is provided in the receptacle, the pads on the corresponding edge card will also need to be similarly offset.

[037] As depicted, the module 50 (which is a SFP style module) includes a housing 52 that supports an edge card 50 and the edge card 59 that includes pads 59 in a row Rl and a row R3. The module 50, which may support a pull tab 51 and a cable 53, can have the housing formed of a conductive material if the module is intended for use as an external module and of an insulative material if the module is intended for internal use. The depicted module is configured to provide additional data channels and thus include pads 59 on an extension portion 58 of the edge card 55 that are in another row R2. As can be appreciated, the row R2 is on an opposite side of the edge card 55 as the row Rl (which supports the standard high data rate channels in a conventional SFP style application) and row R2 is also offset forward toward a front edge 56 of the edge card 55 rather than directly opposing the row Rl. This has been determined to be useful to help prevent cross talk on the channels.

[038] Thus, signal pair SP1 is configured to engage a pair of pads 59 in row Rl on a first side 55a of the edge card 55 and a second signal pair SSP is configured to engage another pair of pads 59 in row R2 on a second side 55b of the edge card. Thus, the terminals that provide the second signal pair SSP are supported by the same wafers that support the terminals that provide the signal pair SP1. This allows the potential for signal wafers and ground wafers to have a different construction if it is determined to be beneficial. In any event, if desired the wafers that support the signal terminals can be inserted into housing 112 in a coupled manner (e.g., two adjacent wafers inserted into the housing at a time) while the wafers that support the ground terminals are loaded in a more individual manner, it being understood that coupled or single wafers could be inserted into a housing individually or in a ganged manner as desired.

[039] As is known, the pads on the edge card can be electrically coupled to conductors in a cable. A typical SFP style cable would include at least two conductor groups CI, C2 that each supported a channel suitable for use at a data rate of 10 Gbps over a reasonable distance of 2 or more meters. The actual construction of the conductor group could vary substantially and depending on materials, the conductor group might be suitable for use over longer distances. It has been determined that data rates of 15-25 Gbps require conductor groups with higher performance. For example, due to the higher frequencies, signal attenuation occurs more rapidly with the same gauge conductor. Consequentially, when providing two or more of the other conductor groups (conductor groups C3-C5) that are electrically coupled to pairs of pads in the row R2, it has been determined that it would be beneficial to offer conductor groups that have improved performance. This may include a more consistent impedance profile along the cable, increased tolerances and more capable materials. In any event, conductor groups C3-C5 preferably provide performance equal to or better than the performance provided by conductor groups C1-C2.

[040] As can be appreciated, when a module is mated to the receptacle such that an edge card is directed through the card slot 115, 116a, the edge card will first engage a contact row 130a that engages both sides of the edge card. This engagement is provided by terminal row TR1 and terminal row TR3 (these terminals can be considered a first set of terminals). If the module is configured to offer more than the standard high data rate channels (which in the case of the SFP style design is two but could be some other number of channels), then an extension portion 58 will engage a second contact row 131a provided by terminal row TR2 (these terminals can be considered a second set of terminals). However, if the module is not configured to provide more than the standard data rate channels, the module may omit the extension portion 58 and the second contact row 131a will not engage the edge card.

[041] In the depicted embodiment, as two ports are provided in a stacked manner, a first contact row 130b and a second contact row 131b are similarly configured with terminal rows TR1 ', TR2' and TR3' (although in the depicted belly-to-belly configuration the lower port is configured in an orientation that is opposite the upper port). If desired, the upper and lower port could also be configured in the same orientation, although it is expected that such a configuration might require additional space to ensure appropriate cross-talk performance.

[042] One benefit of the depicted configuration is that the terminal row TR2 can offer three second signal pairs SSP1, SSP2, SSP3 that are each capable of supporting high data rates. This, as can be appreciated, allows the aggregate data rate of a connector system to more than double. For example, if the data channels for SP1 and SP2 each supported 20 Gbps channels, the three second signal pairs could each provide an additional 20 Gbps data channel so as to provide an additional 60 Gbps of aggregate data channel bandwidth. Thus, the depicted system allows for a substantial flexibility and future upgrade paths that otherwise would require replacement of the entire system. [043] In addition, the data channels supported by the signal pairs SP1 and SP2 might be configured to provide a data channel of 10 Gbps (essentially providing what is known as a IX bi-directional data channel of 10 Gbps). The contact row 131a can provide a secondary set of transmit and receive channels (thus providing something similar to a 2X) connector but can be configured to provide a channel that offers a 15 Gbps, 20 Gbps or even 25 Gbps data-rate. This can be accomplished, in part, because the standard terminals that form contact row 130a are type A (e.g., stamped terminals) while the terminals that for contact row 131a are type B (e.g., stamped and formed).

[044] Thus, the use of the receptacle allows compatibility with a legacy 10 Gbps data- channel system but also enables an upgrade to additional data channels which much higher data rates (such as 25 Gbps). As can be appreciated, a module configured to function with both data channels can be mounted in a cable system that offers substantially greater architectural flexibility than previously possible. For example, it can be positioned as part of a fan-out cable system or provide a link between two points that can initially be adequately supported by a 10 Gbps data channel but is easily upgradeable to a 25 Gbps data channel (or through a combination of both the 10 Gbps and 25 Gbps data channels, an effective 35 Gbps data channel).

[045] The disclosure provided herein describes features in terms of preferred and exemplary embodiments thereof. Numerous other embodiments, modifications and variations within the scope and spirit of the appended claims will occur to persons of ordinary skill in the art from a review of this disclosure.

Claims

We claim:

1. A receptacle configured to receive a module, the receptacle comprising:

a housing with a card slot, the card slot having opposing first and a second sides and a front face;

a first set of terminals positioned in the slot, the first set of terminals including an first terminal row and a second terminal row, the first and second terminal rows configured, in operation, to provide a first contact row that engages opposite sides of a mating edge card, the first terminal row including at least two signal pairs that each support a data rate of at least 10 Gbps; and

a second set of terminals positioned in the slot and configured, in operation, to provide a third terminal row that engages the same side of the edge card as the second terminal row, the second terminal row providing a second contact row that is positioned further from the front than the first contact row.

2. The receptacle of claim 1, wherein the second set of terminals provides at least two signal pairs that are each configured to provide a data rate of at least 15 Gbps.

3. The receptacle of claim 1, wherein the terminals that form the first terminal row each have a contact, the contacts spaced apart on a predetermined pitch, and wherein the terminals that form the second set of terminals have contacts spaced apart on the

predetermined pitch, the contacts of the second terminal row being offset compared to the contacts of the first terminal row.

4. The receptacle of claim 1, wherein the housing includes a second card slot, the second card slot configured with terminals so as to provide an orientation opposite the first card slot, wherein, in operation, the two card slots are configured to accept two modules in a bell-to-belly configuration.

5. A module configured to mate with a receptacle, the module comprising: a housing supporting a latch;

a edge card supported by the housing, the edge card have a first and second side, the first side supporting a first row of pads and the second side supporting a second row of pads, the first and second row of pads being aligned in an opposing orientation, the edge card having an extension portion, the extension portion supporting a third row of pads on the second side.

6. The module of claim 5, further comprising a cable extending from a year of the housing, wherein the first row of pads includes a first pair of pads and a second pair of pads, the first and second pair of pads being electrically coupled to a first and second set of conductors configured to provide a first and second data channel, the cable further comprising a first and second conductor group electrically connected to the first and second pair of pads, the cable supporting at least a third and fourth conductor group, the third and fourth conductor group coupled to a third and fourth pair of pads in the third row, wherein the third and fourth conductor group are configured to provide data channels that enable a data rate equal to or greater than a data rate enabled by the first and second conductor group.

7. The module of claim 5, wherein the first, second and third row of pads are each at the same pitch.

8. The module of claim 7, wherein the third row of pads is offset with respect to the first row of pads.

9. The module of claim 8, wherein the second row of pads is offset with respect to the first row of pads and the third row of pads.