Ground shield contact member

Abstract

The electrical connector includes a housing having at least one slot for receiving an electrical wafer. Signal contacts are disposed on a first side of the at least one slot. Signal contact resilient contact arms apply a first normal force to an electrical wafer inserted into the at least one slot. At least one ground shield contact member is disposed on a second side of the at least one slot. The ground shield resilient contact arms apply a second normal force to a wafer inserted into the at least one slot. The second normal force applied by the ground shield resilient contact arms is greater than the first normal force applied by the signal contact resilient contact arms. The wafer is biased toward the signal contact resilient contact arms of the signal contacts regardless of the wafer's thickness.

Description

[Technical Field]

[0001] The present invention relates to a ground shield contact member that integrates the functions of ground contact and shielding into a single component. In particular, the ground shield component serves multiple purposes for signal integrity (SI), connector mechanical requirements, and manufacturability. [Background technology]

[0002] The increasing complexity of electronic components has led to a desire to fit more components into smaller spaces on circuit boards or other substrates. As a result, the spacing between electrical terminals within a connector is decreasing while the number of electrical terminals accommodated in the connector is increasing, thereby increasing the need for electrical technology for electrical connectors that can accommodate ever-increasing speeds and to accommodate those speeds with ever-increasing pin densities. It is desirable for such connectors to not only have a reasonably constant impedance level, but also to have acceptable levels of impedance and crosstalk, as well as other acceptable electrical and mechanical properties. Therefore, as signal speeds increase and connector footprints remain the same or become smaller, there remains a need to provide adequate shielding to maintain signal integrity and minimize crosstalk. Summary of the Invention [Problem to be solved by the invention]

[0003] Therefore, it would be advantageous to provide a ground shield contact member that integrates the functions of ground contact and shielding into a single component. It would also be advantageous to provide a connector assembly that minimizes the signal path of the signal contacts to improve signal integrity. [Means for solving the problem]

[0004] A solution is provided by a connector system that includes a ground shield contact component that integrates the functions of ground contact and shielding into a single component. The ground shield component serves multiple purposes for signal integrity, connector mechanical requirements, and manufacturability. The ground shield contact connects from the backplane to the backside ground plane of the connector system at the wafer, thereby providing both a ground connection and the necessary shielding in the area of ​​the backplane signal contacts. Mechanically, the ground shield contact presses the connector wafer toward the plastic housing wall adjacent to the signal contacts, thereby reducing tolerance stackup that contributes to variations in normal force between the signal contacts and the wafer mating pads. The ground shield contact is designed to meet signal integrity parameters; therefore, regular ground contacts do not need to be connected (stitched) adjacent to the signal contacts of the backplane connector.

[0005] The invention will now be described, by way of example only, with reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0006] [Figure 1] 1 is a bottom perspective view of an exemplary mating connector assembly, with the exemplary daughter card connector assembly mated to the exemplary backplane connector assembly. FIG. [Figure 2] 2 is a perspective view of the exemplary connector assembly of FIG. 1, with the daughter card connector assembly and the backplane connector assembly shown unmated. [Figure 3] FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 1. [Figure 4] 3 is a rear perspective view of one of the exemplary ground shield contact members of the backplane connector assembly of FIG. 2. [Figure 5] FIG. 5 is a front perspective view of the ground shield contact member of FIG. 4. [Figure 6] 5 is a side view of the ground shield contact member of FIG. 4. [Figure 7] 1 is a cross-sectional view of an exemplary single mating cavity of a backplane connector assembly with each wafer of the connector assembly partially inserted into the mating cavity. [Figure 8] 8 is a cross-sectional view of a single mating cavity of FIG. 7 with each wafer fully inserted into the mating cavity and the ground shield contact spring fingers of the ground shield contact members biasing the wafer toward the signal contact beams of the backplane connector assembly. [Figure 9] FIG. 10 is a perspective view of the ground shield contact members of the backplane connector assembly engaging with respective wafers of the connector assembly, the housing of the backplane connector and the connector assembly not shown. [Figure 10] FIG. 10 is a perspective view of the signal contact beams of the backplane connector assembly engaging with their respective wafers of the connector assembly, with the housing of the backplane connector and the connector assembly not shown. [Figure 11] FIG. 10 is a front perspective view of another exemplary ground shield contact member of a backplane connector assembly. [Figure 12] 12 is a perspective cross-sectional view of a plurality of ground shield contact members of FIG. 11 disposed in an exemplary backplane connector. DETAILED DESCRIPTION OF THE INVENTION

[0007] The connector system includes a ground shield contact component that integrates the functions of ground contact and shielding into a single component. The ground shield component serves multiple purposes for signal integrity, connector mechanical requirements, and manufacturability.

[0008] The ground shield contacts provide a connection from the backplane to the backside ground plane of the connector system at the wafer, thereby providing both a ground connection and the necessary shielding in the area of ​​the backplane signal contacts. Mechanically, the ground shield contacts press the connector wafer toward the plastic housing wall adjacent to the signal contacts, thereby reducing tolerance stackup that contributes to variations in normal force between the signal contacts and the wafer mating pads. The ground shield contacts are designed to meet signal integrity parameters; therefore, normal ground contacts do not need to be connected adjacent to the signal contacts of the backplane connector.

[0009] An additional benefit is that the ground shield contact can also provide a large current carrying capacity to the wafer based connector system for power wafer variants. The ground shield contact provides a current path to the backside of the power wafer and provides a large surface area for heat sinking.

[0010] The ground shield contact provides a positive, low resistance connection between the BP PCB and the wafer in wafer-based connectors. It also biases the wafer for a more consistent normal force from the wafer to the signal contacts, reducing tolerance stackup. It also provides a positive, low resistance connection in power wafer applications, increasing current carrying capacity.

[0011] An embodiment relates to an electrical connector including a housing having at least one slot for receiving an electrical wafer. Signal contacts are disposed on a first side of the at least one slot. The signal contacts have signal contact resilient contact arms extending into the at least one slot. The signal contact resilient contact arms apply a first normal force to an electrical wafer inserted into the at least one slot. At least one ground shield contact member is disposed on a second side of the at least one slot. The second side is opposite the first side. The at least one ground shield contact member has a ground shield resilient contact arm extending into the at least one slot. The ground shield resilient contact arm applies a second normal force to a wafer inserted into the at least one slot. The second normal force applied by the ground shield resilient contact arm is greater than the first normal force applied by the signal contact resilient contact arm, and the wafer is biased toward the signal contact resilient contact arm of the signal contact regardless of wafer thickness, allowing the first normal force applied to the wafer to be independent of wafer thickness tolerances.

[0012] An embodiment relates to an electrical connector having a ground shield contact element. The ground shield contact element includes a planar ground shield portion. A ground shield resilient contact arm extends from a first end of the planar ground shield portion. The ground shield resilient contact arm is configured to apply a normal force to a wafer inserted into a slot of the electrical connector. The normal force applied by the ground shield resilient contact arm biases the wafer toward the signal contacts of the connector, regardless of the wafer's thickness. The ground shield contact element is configured to provide grounding and shielding.

[0013] 1 and 2 illustrate an exemplary electrical connector system 10 having a backplane connector 12 and a daughter card connector 14 used to electrically connect a backplane circuit board (not shown) and a daughter card circuit board (not shown). While the electrical connector system 10 is described herein with reference to the backplane connector 12 and the daughter card connector 14, it is understood that the subject matter herein may be used with different types of electrical connectors other than a backplane connector or a daughter card connector. The backplane connector 12 and the daughter card connector 14 are merely exemplary of the electrical connector system 10.

[0014] In the exemplary embodiment shown, the daughter card connector 14 comprises a right-angle connector in which the mating interface 16 and the mounting interface 18 of the daughter card connector 14 are oriented perpendicular to one another. The daughter card connector 14 is attached to the daughter card circuit board at the mounting interface 18. In alternative embodiments, other orientations of the interfaces 16, 18 are possible.

[0015] The daughter card connector 14 includes a housing 20 formed from one or more components and holding multiple wafers 22, such as, but not limited to, circuit boards. The wafers 22 may have different configurations, such as, but not limited to, microstrip (two layers) or stripline (four or more layers). In the exemplary embodiment, the wafers 22 have pairs of individual signal paths or traces (not shown) extending between the mating interface 16 and the mounting interface 18. The signal traces have signal conductive pads 24 ( FIG. 10 ) located proximate the mating interface 16. The wafers 22 have a ground plane member 28 ( FIG. 9 ) on the side of the wafer 22 opposite the signal conductive pads 24. The ground plane member 28 extends between the mating interface 16 and the mounting interface 18. In an alternative embodiment, wafer 22 may be a contact module, the signal traces may be mating signal contacts, and the ground traces may be ground contacts.

[0016] In the illustrated embodiment, backplane connector 12 comprises a header connector attached to a backplane circuit board. However, other types of connectors may be used. When backplane connector 12 is mated with daughtercard connector 14, the daughtercard circuit board is oriented generally perpendicular to the backplane circuit board.

[0017] 2, backplane connector 12 includes a mating end 30 and a mounting end 32 that are oriented generally parallel to one another. Backplane connector 12 is attached to a backplane circuit board at mounting end 32. In alternative embodiments, other orientations of mating end 30 and mounting end 32 are possible.

[0018] In the exemplary embodiment, backplane connector 12 includes a unitary housing 34. Alternatively, the housing may include multiple individual housings or modules. Housing 34 has one or more wafer-receiving slots 36 extending from mating end 30 toward mounting end 32. Housing 34 holds at least one row of signal contacts 42 and at least one ground shield contact member 44. At least one row of signal contacts 42 is disposed on one side of one or more wafer-receiving slots 36. At least one ground shield contact member 44 is disposed on the opposite side of one or more wafer-receiving slots 36.

[0019] The signal contacts 42 extend between the mating end 30 and the mounting end 32. In the exemplary embodiment, the signal contacts 42 are arranged in pairs to transmit differential signals. However, in other configurations, the signal contacts 42 may not be arranged in pairs to transmit differential signals, such as to transmit single-ended signals. A ground shield contact member 44 extends between the mating end 30 and the mounting end 32.

[0020] Each signal contact 42 has a resilient contact arm 46, a fixed portion 48, and a circuit board mounting portion 50. In the exemplary embodiment shown, each of the resilient contact arms 46 has a lead-in portion 52 and an engagement portion 54. The resilient contact arms 46 are configured to press against the signal conductive pads 24 of the signal traces on the wafer 22 of the daughter card connector 14 when the daughter card connector 14 is inserted into the wafer-receiving slot 36 of the backplane connector 12.

[0021] The fastening portion 48 has a retention member 56, which may be, but is not limited to, a barb or protrusion extending from a surface of the fastening portion 48. The retention member 56 cooperates with the housing 34 to retain the signal contacts 42 in the backplane connector 12.

[0022] The circuit board mounting portion 50 has a compliant portion 58, such as a needle pin eye, although other configurations may be used. The configuration of the signal contacts 42 is intended to be exemplary, as other embodiments of the signal contacts may be used. For example, the signal contacts 42 may have an asymmetrical or other configuration that allows for optimal performance under different conditions. The circuit board mounting portion 50 cooperates with the backplane circuit board to hold the signal contacts 42 to the backplane circuit board.

[0023] As shown in Figures 3-9, the ground shield contact member 44 has a planar ground shield portion 60. Ground shield resilient contact beams or ground shield contact spring fingers 62 extend from a first end of the ground shield portion 60. In the exemplary embodiment shown, the ground shield contact beams 62 are uniformly spaced along the length of the ground shield portion 60, although other configurations may be used. The ground shield contact member 44 is configured to make a ground connection between the backplane circuit board and the wafer 22, providing both mechanical and signal integrity.

[0024] Each ground shield contact beam 62 has a ground shield resilient contact arm 64 having a lead-in portion 66 and an engagement portion 68. The resilient contact arm 64 is configured to press against the ground plane member 28 of the daughter card connector 14 when the daughter card connector 14 is mated to the backplane connector 12.

[0025] Resilient members 70 extend from the second end of the ground shield portion 60. The second end of the ground shield portion 60 is opposite the first end of the ground shield portion 60. In the exemplary embodiment shown, the resilient members 70 are evenly spaced along the length of the ground shield portion 60, although other configurations may be used. The longitudinal axes of each of the resilient members 70 are offset from the longitudinal axes of each of the ground shield contact beams 62.

[0026] Each of the resilient members 70 has a U-shaped member 72 (as viewed in FIGS. 7 and 8 ) extending from the ground shield portion 60. The U-shaped member 72 is received in a cavity 38 extending from each of the one or more wafer-receiving slots 36. The U-shaped member 72 cooperates with the walls of the cavity 38 to help hold each of the ground shield contact members 44 in place in the housing 34.

[0027] A circuit board engaging surface 74 is provided at each free end of the U-shaped member 72. The circuit board engaging surfaces 74 are configured to engage contact pads on the surface of a backplane circuit board to provide an electrical connection.

[0028] In the illustrated exemplary embodiment, a ground contact 76 is provided at the end of the ground shield portion 60. The ground contact 76 provides an additional ground connection between the ground shield of the daughter card connector 14 and the backplane. The ground contact 76 extends generally perpendicular to the plane of the ground shield portion 60 and has a securing portion 78. In the illustrated embodiment, the securing portion 78 is a needle compliant member eye, although other types of securing portions 78 may be used. A retention tab 80 may be provided on the ground contact 76. The retention tab 80 cooperates with the housing 34 of the backplane connector 12 to secure the ground shield contact member 44 in place.

[0029] 7 and 8, the insertion of wafer 22 into wafer-receiving slot 36 is shown. When daughter card connector 14 is mated to backplane connector 12, mating interface 16 of daughter card connector 14 engages and is inserted onto mating end 30 of backplane connector 12. When this occurs, leading end 40 of wafer 22 is positioned in the respective slot 36 of backplane connector 12.

[0030] As insertion continues, the tip 40 passes through the lead-in portion 52 and contact portion 54 of the resilient contact arm 46 of the signal contact 42, causing the resilient contact arm 46 to move in the direction of arrow A in Figure 8. This movement causes the contact portion 54 of the resilient contact arm 46 to apply a normal force F1 to the wafer 22.

[0031] Continued insertion of wafer 22 into slot 36 causes tip 40 to pass through lead-in portion 66 and contact portion 68 of resilient contact arm 64 of ground shield contact member 44, causing resilient contact arm 64 to move in the direction of arrow B in Figure 8. This movement causes contact portion 68 of resilient contact arm 64 to apply a normal force F2 to wafer 22.

[0032] Due to the configuration of the ground shield contact member 44, including the cooperation of the resilient member 70 and the housing 14, the force F2 applied to the wafer 22 by the resilient contact arm 64 is greater than the force F1 applied to the wafer 22 by the resilient contact arm 46. This causes the resilient contact arm 64 of the ground shield contact member 44 to bias the wafer 22 toward the resilient contact arm 46 of the signal contact 42.

[0033] Because the sum of the normal forces F2 is always greater than the sum of the normal forces F1, the wafer 22 is always biased toward the resilient contact arms 46 of the signal contacts 42, regardless of the thickness T of the wafer 22. Because the wafer 22 is always biased toward the signal contacts 42, the normal force exerted by the resilient contact arms 46 of the signal contacts 42 can be determined and controlled regardless of the thickness T of the wafer 22. The normal force F1 exerted on the wafer 22 is independent of wafer thickness tolerances.

[0034] Because wafer 22 positioning is controlled by the normal force F2 of the resilient contact arms 64 of the ground shield contact member 44, the normal force F1 exerted by the resilient contact arms 46 of the signal contacts 42 must be sufficient to ensure proper contact is made and maintained between the signal contact pads 24 of a properly positioned wafer 22 and the contact portions 54 of the resilient contact arms 46 of the signal contacts 42. Because this normal force is less than that required for known signal contacts, the length of the signal contacts 42 can be minimized as the required force decreases. This allows the length of the resilient contact arms 46 of the signal contacts 42 and the length of the signal contacts 42 to be minimized for signal integrity purposes and still meet the normal force requirements for a reliable contact system.

[0035] Because the overall tolerance from the base of the resilient contact arms 46 of the signal contacts 42 to the front surface of the wafer 22 is reduced, the length of the resilient contact arms 46, and therefore the overall length of the signal contacts 42, can be made shorter (less range of motion is required for mechanical purposes to achieve the required normal force), which improves the signal integrity of the backplane connector 12 because there is less opportunity for crosstalk between the signal contacts 42.

[0036] Another advantage of the present invention is the elimination of ground contacts from known wafer-based connector systems. The ground shield contact members 44 integrate the functions of ground contact and shielding into one component. Additionally, the ground shield contact members 44 can be tuned for signal integrity, eliminating the need for ground contacts between sets of differential contact pairs.

[0037] The ground shield contact members 44 can increase the current / power capacity of a wafer-based power contact system. For high power / current wafers 22, the ground shield contact members 44 provide a current path to the backside of the wafer 22 in addition to the current path on the frontside of the wafer provided by the signal contacts 42, as shown in FIG.

[0038] 11 and 12, an alternative exemplary ground shield contact member 144 has a planar ground shield portion 160. Ground shield resilient contact beams or ground shield contact spring fingers 162 extend from a first end of the ground shield portion 160. In the exemplary embodiment shown, the ground shield contact beams 162 are spaced approximately uniformly along the length of the ground shield portion 160, with larger spaces 161 in one area, although other configurations may be used. Similar to the ground shield contact member 44, the ground shield contact member 144 is configured to make a ground connection between the backplane circuit board and the wafer 22, providing both mechanical and signal integrity.

[0039] Each ground shield contact beam 162 has a ground shield resilient contact arm 164 having a lead-in portion 166 and an engagement portion 168. The resilient contact arms 164 are configured to press against the ground plane member 28 of the daughter card connector 14 when the daughter card connector 14 is mated to the backplane connector 112.

[0040] A fixed portion 170 extends from a second end of the ground shield portion 160. The second end of the ground shield portion 160 is opposite the first end of the ground shield portion 160. In the exemplary embodiment shown, the fixed portion 170 is bent out of the plane of the ground shield portion 160. A portion 172 of the fixed portion 170 extends generally perpendicular to the ground shield portion 160, although other configurations may be used.

[0041] As shown in FIG. 12, the fasteners 170 cooperate with fastener projections 174 on the backplane connector 112 to retain the ground shield contact members 144 in the backplane connector 112 .

[0042] Attachment members 176 extend from fixed portion 170. Attachment members 176 are generally parallel to, but offset from, the plane of ground shield portion 160. In the illustrated embodiment, attachment members 176 are needle compliant member eyes, although other types of attachment members 176 may be used. Attachment members 176 are configured to engage through holes in a backplane circuit board to provide electrical connection.

[0043] The function and operation of ground shield contact member 144 and ground shield contact beam 162 are identical to the function and operation of ground shield contact member 44 and ground shield contact beam 62. The benefits and advantages of using ground shield contact member 144 are also identical to the benefits and advantages of ground shield contact member 44.

Claims

1. 1. An electrical connector comprising: a housing having at least one slot for receiving an electrical wafer; a signal contact disposed on a first side of the at least one slot, the signal contact having a signal contact resilient contact arm extending into the at least one slot, the signal contact resilient contact arm applying a first normal force to the electrical wafer inserted into the at least one slot; at least one ground shield contact member disposed on a second side of the at least one slot, the second side being opposite the first side, the at least one ground shield contact member having a ground shield resilient contact arm extending into the at least one slot, the ground shield resilient contact arm applying a second normal force to the wafer inserted in the at least one slot; Equipped with the second normal force exerted by the ground shield resilient contact arm is greater than the first normal force exerted by the signal contact resilient contact arm; The electrical connector wherein the wafer is biased toward the signal contact resilient contact arm of the signal contact regardless of the thickness of the wafer, allowing the first normal force applied to the wafer to be independent of wafer thickness tolerances.

2. 2. The electrical connector of claim 1, wherein the at least one ground shield contact member comprises a planar ground shield portion, the ground shield resilient contact arm extending from a first end of the planar ground shield portion.

3. 3. The electrical connector of claim 2, wherein said ground shield resilient contact arms are uniformly spaced along the length of said planar ground shield portion.

4. 4. The electrical connector of claim 3, wherein the ground shield resilient contact arm has a lead-in portion and a contact portion, the contact portion pressing against a ground plane member of the wafer when the wafer is inserted into the at least one slot.

5. 4. The electrical connector of claim 3, wherein a resilient member extends from a second end of the planar ground shield portion, the second end of the planar ground shield portion being opposite the first end of the planar ground shield portion.

6. 6. The electrical connector of claim 5, wherein said resilient members are uniformly spaced along said length of said planar ground shield portion.

7. 7. The electrical connector of claim 6, wherein a longitudinal axis of each of said resilient members is offset from a longitudinal axis of each of said ground shield resilient contact arms.

8. 7. The electrical connector of claim 6, wherein the resilient member comprises a U-shaped member.

9. 9. The electrical connector of claim 8, wherein a circuit board contact surface is provided at a free end of the U-shaped member, the circuit board contact surface being configured to contact contact pads on a surface of a backplane circuit board to effect electrical connection.

10. 3. The electrical connector of claim 2, wherein a securing portion extends from a second end of the planar ground shield portion, the second end of the planar ground shield portion being opposite the first end of the planar ground shield portion.

11. 11. The electrical connector of claim 10, wherein the securing portion is bent out of the plane of the ground shield portion, and the securing portion cooperates with a securing protrusion of the connector to retain the ground shield contact member in the connector.

12. The electrical connector of claim 11 , wherein a portion of the fastening portion extends substantially perpendicular to the ground shield portion.

13. 12. The electrical connector of claim 11, wherein a mounting member extends from the fixed portion, the mounting member configured to engage a through hole in a backplane circuit board to provide an electrical connection.

14. 3. The electrical connector of claim 2, wherein a ground contact is provided at an end of said planar ground shield portion of said at least one ground shield contact member.

15. 10. The electrical connector of claim 1, wherein the at least one ground shield contact member provides a ground connection from a backplane circuit board to which the electrical connector is mounted to a ground plane of the wafer, the at least one ground shield contact member providing mechanical stability and signal integrity.

16. The electrical connector of claim 1 , wherein the at least one ground shield contact member provides grounding and shielding for the electrical connector.

17. 2. The electrical connector of claim 1, wherein the signal contact comprises a resilient contact arm, a fixed portion, and a mounting portion.

18. 18. The electrical connector of claim 17, wherein the signal contact resilient contact arm has a lead-in portion and a contact portion, and the contact portion presses against a signal conductive pad of the wafer when the wafer is inserted into the at least one slot.

19. 10. The ground shield contact assembly of claim 1, wherein the signal contact length across the signal contact is minimized for signal integrity purposes while still meeting normal force requirements for a reliable contact system.

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