Hybrid electrical connector for high-frequency signals

Abstract

A hybrid electrical connector for high-frequency signals. A connector includes: a housing; a cage surrounding the housing; first contacts located in the housing and transmitting high-speed signals; second contacts located in the housing and transmitting low-speed signals, each second contact including a portion extending from a top surface of the housing; a first cable connected to the first contacts; and a second cable connected to the second contacts.

Description

[0001] This application is a divisional application of the invention patent application with the application date of October 24, 2019, application number 201980069205.6 (international application number PCT / US2019 / 057826), and invention name “Hybrid electrical connector for high-frequency signals”. Background of the Invention

[0002] 1. Field of the Invention

[0003] The present invention relates to electrical connectors and, more particularly, to hybrid high-frequency electrical connectors that include a connection to a cable and a connection to a substrate or circuit board.

[0004] 2. Description of Related Technology

[0005] Electrical connectors are used to enable electronic devices such as substrates or printed circuit boards (PCBs) to communicate with each other. Electrical connectors are also used along paths between electronic devices to connect cables to other cables or PCBs. A connector can be thought of as having two parts: a first part that connects to a first electronic device or a first cable, and a second part that connects to a second electronic device or a second cable, wherein the second electronic device or the second cable is to be in communication with the first device or the first cable. To connect two electronic devices or cables, the first and second parts of the connector dock together.

[0006] The connector may include a first set of contacts in a first portion and a second set of contacts in a second portion to be connected to the contacts in the first portion. When the male and female connectors are mated, the male and female connectors can be easily mated by providing corresponding sets of contacts for the male and female connectors to engage. Furthermore, the male and female connectors can be connected and disconnected from each other to electrically connect and disconnect the electronic devices to which they are connected, respectively.

[0007] Thus, the first connector portion and the second connector portion are connected to the electronic device or cable via their contacts. The contacts are typically permanently connected to the electronic device or cable. For example, the first connector portion can be connected to the cable, and the second connector portion can be connected to the PCB. The first connector portion can be connected to the second connector portion to enable signals to be transmitted to and from devices on and / or within the PCB. The second connector portion is connected to the devices on and / or within the PCB via electrical traces etched into the PCB.

[0008] Various standards and specifications have been proposed and implemented for electrical connectors that transmit high-frequency signals. One example is the Quad Small Form-factor Pluggable (QSFP / QSFP+), a specification for compact, hot-swappable transceivers commonly used in data communication systems. Figure 1 is a perspective view of a conventional QSFP / QSFP+ connector disclosed in U.S. Patent Application No. 2016 / 0218455, which is limited to a data transmission rate of approximately 10 Gbits / second per channel (approximately 40 Gbits / second total).

[0009] As shown in Figure 1, a docking cable 4 is connected to a male QSFP connector 1, which is docked with a female QSFP connector 2A. The female QSFP connector 2A is contained within a cage 2 mounted to a PCB 5. The male QSFP connector 1 includes a housing 1A and a circuit board 10. The cage 2 of the female QSFP connector 2A includes a heat sink 3. The input signal from the docking cable 4 is transmitted between the connector 1 and the connector 2A, and then transmitted to the PCB 5. The signal is then transmitted through electrical traces (not shown) in or on the PCB 5. For example, the signal can be transmitted to an integrated circuit (IC) or other electrical component via the electrical traces in the PCB 5. However, since the female QSFP connector 2A is terminated to the PCB 5, this arrangement results in a bottleneck in data transmission.

[0010] Figure 2 is a graph comparing the signal insertion loss through a cable and the signal insertion loss through a trace on a PCB 5. As shown in Figure 2, even a "low-loss" etched electrical trace in a PCB has significantly greater signal insertion loss than a #28AWG (American Wire Gauge) cable of the same length, especially at higher frequencies. For example, at a frequency of 20 GHz, the signal insertion loss through the cable is approximately 36 dB different than through the PCB trace.

[0011] Therefore, while cables provide signal paths with high signal integrity (e.g., optical cables or shielded cables, such as coaxial cables or twinax cables), electrical traces in PCBs provide signal paths with lower signal integrity, especially at higher frequencies. In particular, electrical traces in PCBs have much higher differential signal insertion loss than optical cables or shielded cables and are more susceptible to interference and crosstalk, even if components (such as ICs) are placed on the PCB adjacent to the female QSFP connector 2A.

[0012] Figure 3 illustrates a plan view of substrate 14, comparing the footprint of a known multi-source agreement (MSA) QSFP-DD compatible connector. As shown in Figure 3, the footprint includes an array of connection pads 16 to which a receptacle body of a known MSA QSFP-DD compatible connector can be mounted, and includes press-fit holes 18 into which shrouded press-fit tails and the press-fit tails of the receptacle body of the known MSA QSFP-DD compatible connector can be inserted. Summary of the Invention

[0013] To overcome the aforementioned problems, embodiments of the present invention provide an electrical connector that connects to a secondary substrate using both low-speed connections and high-speed connections, wherein the low-speed connections connect to electrical traces in the secondary substrate to transmit low-frequency signals, ground, and power, and the high-speed connections connect to cables to transmit high-frequency signals. In other words, the connector according to embodiments of the present invention is a hybrid connector having both a cable connection for transmitting high-frequency signals and a board connection for transmitting other signals.

[0014] One technical solution described herein is the mating of a first electrical connector having a first mating interface, a first mounting interface, and a cable attached to a substrate footprint, the first electrical connector being configured to receive a second electrical connector having the first mating interface, a second mounting interface different from the first mounting interface, and no attached cable. For example, the first electrical connector may be an FQSFP-DD receptacle cable connector manufactured by SAMTEC, Inc., while the second electrical connector may be a QSFP-DD receptacle board connector. In other words, the first electrical connector may include a first mating interface, a first mounting interface, and N electrical contacts, and the first electrical connector may be modified to form a second electrical connector having the first mating interface, a second mounting interface different from the first mounting interface, and the same N electrical contacts. The second mounting interface may correspond to the substrate footprint. Each first mounting end of a given number of the N electrical contacts defines a first mounting interface of a second electrical connector housing, and each second mounting end of a given number of the N electrical contacts extends from another side of the second electrical connector housing to accommodate an attached cable. Another side of the second electrical connector housing, such as a top surface, can be positioned parallel to the first mounting interface or the second mounting interface so that the corresponding second mounting end corresponds to and does not interfere with a substrate footprint. The substrate footprint can be a QSFP-DD board connector footprint, as shown in FIG3 .

[0015] According to an embodiment of the present invention, a connector includes: a housing; a cage surrounding the housing; first contacts located in the housing and transmitting high-speed signals; second contacts located in the housing and transmitting low-speed signals, and each second contact includes a portion extending from a top surface of the housing; a first cable connected to the first contact; and a second cable connected to the second contact.

[0016] The connector may further include a control substrate, wherein the portion of each second contact extending from the top surface of the housing is connected to the control substrate, and the second cable is connected to the second contact through the control substrate. The second cable may be crimped to the portion of each second contact extending from the top surface of the housing. The connector may further include a wafer located within the housing, wherein the second contact is included in the wafer. The connector may further include additional second contacts located in the housing, the additional second contacts transmitting a low-speed signal, each additional second contact including a portion extending from the bottom surface of the housing and not connected to any cable.

[0017] The connector may further include an additional first contact positioned within the housing and connected to ground. The first cable may include a shield, and the additional first contact may be connected to the shield. Each second contact may include a right-angle bend. The connector is compatible with the QSFP specification.

[0018] According to an embodiment of the present invention, a connector system includes a base substrate and a connector according to one of the other embodiments of the present invention connected to a first surface of the base substrate.

[0019] The connector system may further include an additional connector connected to a second surface of the base substrate opposite the first surface, wherein the additional connector includes a housing and a cage surrounding the housing. The additional connector is compatible with the QSFP specification.

[0020] According to an embodiment of the present invention, a stacked connector includes a first connector and a second connector, the first connector including a first low-speed contact and a first high-speed contact; the second connector is stacked on top of the first connector, and the second connector includes a second low-speed contact and a second high-speed contact, wherein each second low-speed contact includes a portion extending from a top surface of the second connector; a cage surrounding the first connector and the second connector; a first high-speed cable connected to the first high-speed contact; a second high-speed cable connected to the second high-speed contact; and a low-speed cable connected to the second low-speed contact.

[0021] The stacking connector may further include a control substrate, wherein a portion of each second low-speed contact extending from a top surface of the second connector is connected to the control substrate, and the low-speed cable is connected to the second low-speed contact through the control substrate. The low-speed cable may be crimped to the portion of each second low-speed contact extending from the top surface of the second connector.

[0022] The first connector may further include additional first low-speed contacts, each of the additional first low-speed contacts including a portion extending from the bottom surface of the housing and not connected to any cable. The first low-speed contacts may be connected to a low-speed cable. The stacking connector may further include a spacer between the first connector and the second connector. The first connector and the second connector are compatible with the QSFP specification.

[0023] According to an embodiment of the present invention, a stacking connector system includes a base substrate, and a stacking connector system according to one of various other embodiments of the present invention connected to the base substrate.

[0024] According to an embodiment of the present invention, a connector system includes: a base substrate, a first connector connected to a first surface of the base substrate, and including a first housing including first contacts directly connected to the base substrate in a first region and a first cage surrounding the first housing; and a second connector connected to a second surface of the base substrate opposite the first surface, and including a second housing including second contacts directly connected to the base substrate in a second region and a second cage surrounding the second housing. In a horizontal projection view relative to the base substrate, the first region and the second region do not overlap.

[0025] The first connector and the second connector are compatible with the QSFP specification.

[0026] A connector may include a housing, a cage surrounding the housing, a first contact, a second contact, and a second cable electrically connected to the second contact, wherein the first contact: (i) is located in the housing; (ii) transmits a high-speed signal; (iii) is configured to be attached to a mounting substrate, and (iv) defines a mounting interface, and the second contact: (i) is located in the housing; (ii) transmits a low-speed signal; and (iii) each includes a portion extending from a top surface of the housing, wherein the top surface of the housing is parallel to the mounting interface.

[0027] The above and other characteristics, elements, steps, configurations, features and advantages of the present invention will become more apparent from the following detailed description of embodiments of the present invention with reference to the accompanying drawings.

[0028] BRIEF DESCRIPTION OF THE DRAWINGS

[0029] FIG1 is a perspective view of a conventional QSFP connector.

[0030] FIG. 2 is a graph comparing signal loss through a cable and signal loss through traces on a printed circuit board (PCB).

[0031] FIG3 shows a plan view of the footprint of a known QSFP-DD connector.

[0032] Figure 4 and Figure 5 1 and 2 are front and rear perspective views of a connector according to a first embodiment of the present invention.

[0033] Figure 6 yes Figure 4 and Figure 5 A cross-sectional view of the connector is shown in FIG.

[0034] Figure 7 It can be used with Figure 4 and Figure 5 A front view of the connector body for use with the connector shown in FIG.

[0035] Figure 8 and Figure 9 yes Figure 4 and Figure 5 Exploded front and rear perspective views of the connector shown in .

[0036] Figure 10 and 11 is arranged to mate with a male QSFP connector or similar Figure 4 and Figure 5 Top and bottom perspective views of the connector shown in .

[0037] Figures 12 and 13 are Figure 4 and Figure 5 A cross-sectional view of the connector is shown in FIG.

[0038] Figure 14 and 15 yes Figure 7 A close-up perspective view of the contacts of the connector body is shown in FIG.

[0039] Figure 16 yes Figure 7 A side view of the contacts of the connector body is shown in FIG.

[0040] Figure 17 Is a twin-axial cable with Figure 4 and Figure 5 A perspective view of the connections between contacts of the connector shown in FIG.

[0041] Figure 18 and 19A view of the crimped connection to the contact.

[0042] Figures 20 to 24 is a view of a connector according to a second embodiment of the present invention.

[0043] Figures 25 to 27 is a perspective view of a connector according to a third embodiment of the present invention.

[0044] Figures 28 to 30 is a perspective view of a connector according to a fourth embodiment of the present invention.

[0045] Figure 31 A plan view showing the footprint of a connector according to a fourth embodiment of the present invention.

[0046] Figure 32 is a perspective view of a connector body according to a fourth embodiment of the present invention.

[0047] Figure 33 is a diagram illustrating a method for assembling an integrated PCB assembly.

[0048] Detailed description of embodiments

[0049] Now refer to Figures 4 to 32 The embodiments of the present invention are described in detail. Note that the following description is illustrative rather than restrictive in all aspects and should not be interpreted as limiting the application or use of the present invention in any way.

[0050] Figure 4 and Figure 5 1 and 2 are front and rear perspective views of a connector 20 according to a first embodiment of the present invention. Figure 6 is a cross-sectional view of the connector 20 . Figure 7 yes Figure 4 and Figure 5 A front view of the connector 20 is shown. Figure 8 and Figure 9 yes Figure 4 and Figure 5 The connector 20 is shown in exploded front and rear perspective views.

[0051] like Figures 4 to 9 As shown, the connector 20 may include a connector body 30 having a cable 31 extending from the connector body 30 and a control printed circuit board (PCB) 60 having a PCB cable 61 extending from the control PCB 60. Figure 4 and Figure 5As shown, the PCB cable 61 can be attached to the bottom side, ie the side facing the connector body 30. The PCB cable 61 can be soldered to the control PCB 60 using, for example, a laser, a thermode, or manual soldering. Figure 18 and Figure 19 , the PCB cable 61 can also be attached to the top side, i.e., the side opposite the side facing the connector body 30, as shown in FIG. All low-speed signals can be transmitted through the control PCB 60. Some low-speed signals, such as ground and power, can also be transmitted through the control PCB 60 and through the substrate 40. The connector 20, the connector body 30, or both the connector 20 and the connector body 30 can include conductive, magnetically absorbent material, non-conductive, magnetically absorbent material, or both.

[0052] The cage 21 can surround the connector body 30 and the control PCB 60 and can receive a corresponding mating connector (in Figures 4 to 9 Not shown, but in Figure 10 and Figure 11 The cage 21 may include an open top as shown, or similar Figure 10 and Figure 11 The cage 21 shown is closed. A heat sink (not shown) can be attached to the cage 21 so that the heat sink engages with the top of the docking connector through the opening. The control PCB 60 can be mounted to the connector body 30, and the connector body 30 is mounted to the substrate 40. The substrate 40 can be a PCB, but other suitable substrates can also be used. The connector body 30 can include one or more alignment pins on the top connector body 30 to assist in aligning the control PCB 60 with the connector body 30. The control PCB 60 can include a press-fit hole, and the press-fit tail of the contact 37b of the second housing 33 can be inserted into the press-fit hole.

[0053] like Figure 7 As shown, the connector body 30 includes a first shell 32 and a second shell 33. The first shell 32 includes a contact 36 and a contact 37a. The second shell 33 includes a contact 37b. The contact 36 can be a high-frequency contact that can be used to transmit high-speed signals, such as data signals, while the contacts 37a and 37b can be low-frequency contacts that can be used to transmit low-speed signals, such as control signals and power. The cable 31 and the PCB cable 61 extend from the second shell 33. Figure 6 As shown, contacts 36 and contacts 37a can be arranged in a dual-density layout. That is, contacts 36 and contacts 37a can be arranged at the top and bottom of first housing 32 and arranged in two rows. This arrangement enables contacts 36 and contacts 37a to contact an edge card that is inserted into first housing 32 in two rows at both the top and bottom of the edge card.

[0054] First housing 32, second housing 33, and cage 21 may include edge pins 35 and cage pins 23 that mate with corresponding mounting holes in substrate 40 to mechanically secure connector 20 to substrate 40. Edge pins 35 and cage pins 23 may also provide a ground connection to a ground plane 41 or a ground trace in substrate 40.

[0055] The second housing 33 can provide strain relief for the cable 31, and the cage 21 can provide a frame ground connection for the connector 20 and can directly contact the second housing 33 to help secure the connector 20 to the substrate 40. The cage pins 23 can engage with a ground plane 41 included in or on the substrate 40. The second housing 33 can include a grommet at the end of the second housing 33 opposite the first housing 32. If included, the grommet can be an electromagnetic interference (EMI) gasket connected to the cage 21 and can be additionally connected to the shielding of the cable 31. The grommet can be molded to provide a secure snap fit over the second housing 33 and / or inserted into the second housing 33.

[0056] The connector 20 can be a female connector. Although the connector 20 is shown as a receptacle connector configured to receive the docking card edge of a docking connector (such as a QSFP or QSFP+ or QSFP-DD connector), the connector 20 can use other types of connectors / cables, including, for example, Serial Small Computer System Interface (SAS) / Mini SAS, High Density (HD) Mini SAS, CX4, InfiniBand, Serial Advanced Technology Attachment (SATA), Small Computer System Interface (SCSI), QSFP+, SFP+ / SFP (Small Form Factor Pluggable), High Definition Multimedia Interface (HDMI) cable, Universal Serial Bus (USB) cable, DisplayPort cable, CDFP, and other suitable connector / cable types. The first housing 32 can be configured so that it is compatible with a male FSP connector or a male QSFP connector.

[0057] The cable 31 can be a shielded cable, for example, a coaxial cable, a twinax cable, a triax cable, a twisted pair, a flexible printed circuit, a flat flexible circuit, etc. The cable can be arranged as a differential pair, a twinax cable, for example. The cable 31 can be connected to the substrate 40 at a distance of less than about 5 mm or about 10 mm from the control circuit to limit the length of the associated trace. In addition, the length of the signal path for high-speed signals through the cable 31 can be longer than the length of the signal path through the substrate 40 to limit the distance through the high-loss signal path. Compared with the transmission of high-speed signals through high-loss signal paths (such as traces on or within the substrate), the longer cable 31 enables the high-speed signal to be transmitted over a longer distance on the top of the substrate 40, and the longer cable 31 has greater design freedom in enabling any IC that receives or sends high-speed signals to be positioned farther away from the connector 20.

[0058] Connector 20 may be configured similarly to connector 25 so that Figure 10 and Figure 11 The docking connector 80 shown is capable of engaging with the contacts of the first housing 32. Figure 10 and Figure 11 As shown, the docking connector 80 can be attached to the docking cable (in Figure 10 and Figure 11 (not shown), a docking cable can be used to connect the integrated PCB to other components that provide a complex electronic system, such as a computer, a router, a switching network, a PCB control, or other suitable electronic system. The docking cable can be, for example, a passive cable, a shielded cable, or an active optical cable. Figure 10 and Figure 11 An example of a docking connector 80 including a pull tab 82 is shown in FIG. Figure 10 and Figure 11 As shown, connector 25 may be mated with, for example, a male QSFP connector, ie, docking connector 80, via an attached docking cable. However, any similar connector may be used.

[0059] like Figure 7 As shown, the total number and arrangement of contacts 36, contacts 37a, and contacts 37b that the connector body 30 may include are, for example, compatible with the QSFP-DD specification. However, other numbers and arrangements of contacts may be used. In addition, Figure 7 The contact 37a is shown to be arranged in the center portion of the contact row between the contact groups 36, which are arranged in the outer portions of the contact row. Figure 7 As shown, the contacts 37 b may be routed to extend upwardly to the row of contacts at a right angle, or approximately a right angle within manufacturing tolerances, so that the contacts 37 b may terminate to the control PCB 60 .

[0060] Figures 12 and 13 are Figure 4 and Figure 5 12 , and the first housing 32 , the second housing 33 , the cage 21 , the substrate 40 , and the control PCB 60 are not shown in FIG. 13 . Figure 14 and Figure 15 is a close-up perspective view of the contact shown in Figures 12 and 13. Figure 16 Figure 12 to Figure 15 Side view of the contact shown in .

[0061] Figure 17 Cable connections are shown between some of the contacts 36 and the center conductors of corresponding cables 31. For clarity, only a portion of the cables 31 is shown. These cable connections can be used to transmit high-frequency signals, but can also be used to transmit low-frequency signals, control signals, power, etc. Cable 31 can be a twinaxial cable, which includes two center conductors surrounded by a shield and an insulator disposed between the two center conductors and the shield. Cable 31 can be used with differential signals to provide a high degree of signal integrity. The shield of cable 31 is connected to the ground plane 28.

[0062] The connection between the contact 36 and the cable 31 can be a fusible connection provided by a lead-free solder using a typical reflow process. However, the contact 36 and the cable 31 can also be connected by hand soldering, lead-based solder, crimping, ultrasonic welding, and other suitable connection structures.

[0063] like Figure 17 As shown, the contact 36 can be configured so that the contact connected to the center conductor of the cable 31 has an adjacent contact connected to the ground. This enables the electrical path through the connector 20 to be impedance matched with the shielded cable 31 and helps to minimize crosstalk between adjacent channels transmitted in adjacent electrical paths. Each high-frequency channel may include two shielded cables 31, one for sending and one for receiving. A ground connection may be included between the sending channel and the receiving channel. Optionally, the contact 36 can first be connected by tie bars to provide a rigid structure that structurally supports the contact 36 during the manufacture and assembly of the connector 20. After the contact 36 has been arranged in the first housing 32, the tie bars are then cut or stamped, and the first housing 32 is attached to the second housing 33.

[0064] Figure 17 Also shown is a contact connection between contact 37a and contact 37b. In the second housing 33, contact 37b is included in a sheet holder 34. Each sheet holder 34 may include any number of contacts 37b, and any number of sheet holders 34 may be used. For example, Figure 18Five wafer holders 34 are shown, each including four contacts 37b. The wafer holders 34 can be manufactured in any suitable manner, including insert molding around the contacts 37b. The contacts 37b in the wafer holders 34 can include fingers that engage corresponding contacts 37a in the first housing 32 when the second housing 33 is mated with the first housing 32. The contact connections can be used to transmit low-frequency signals, such as control signals, power, and the like.

[0065] Furthermore, the contacts 36, 37a, and 37b can be formed in various shapes. For example, the distance between high-frequency contacts 36 for transmitting differential signals along the length of the contacts 36 can be adjusted to tune the impedance distribution of the contacts 36. The contact 37b in the second housing 33 includes a right-angle bend to carry low-speed signals toward the top of the connector body 30.

[0066] Instead of attaching the cable 31 directly to the connector 20 as discussed above, an interface may be added to the back of the connector 20 so that the cable 31 can be plugged into the interface.

[0067] like Figure 18 and Figure 19 As shown, instead of using the control PCB 60, a crimp 70 can be used at the end of each contact 37 in the sheet holder 34 to attach a cable (not shown). Figure 18 and Figure 19 3. The crimp 70 is bent to any suitable angle. Bending the crimp 70 to an angle of 30° or about 30° within manufacturing tolerances allows the connector to have a minimal profile. Alternatively, other suitable interfaces may be used.

[0068] Figures 20 to 24 is a perspective view of a connector 200 according to a second embodiment of the present invention. Figure 20 is a top perspective view of the connector 200 . Figure 21 is a partially exploded view of the connector 200 . Figure 22 is a cross-sectional view of the connector 200 . Figure 23 is a bottom perspective view of the connector 200 . Figure 24 2 is an exploded view of the connector 200. Figures 20 to 24 As shown, connector 200 is a belly-to-belly configuration that may include two cages: cage 210 and cage 215, with respective connector bodies mounted on a substrate 240. The bottom cage 215 may include a connector body 230, a control PCB 260, and the substrate 240 similar to the configuration described above. Figure 21 、 Figure 22 and Figure 24As shown, the top cage 210 can include a connector body 235. Adding a second cage and connector system increases the available contacts for connecting and carrying signals (i.e., high frequency, low frequency, control signals, power, ground, etc.). The connector body 235 is similar to that described above, but may not include a control PCB with cables. The connector body 235 can be surface mounted to the substrate 240. The array of contacts of the connector body 235 can be physically and electrically connected to a corresponding array of surface mount pads located on the substrate 240. The alignment pins on the connector body 230 can be arranged so as not to interfere with the footprint of the top cage 210 and the connector body 235.

[0069] Figure 23 The bottom perspective drawing and Figure 24 The exploded view in FIG. 1 shows that the bottom connector 220 includes a cage 220 , a connector body 230 with a cable 231 , and a control PCB 260 with a PCB cable 261 .

[0070] Because the docking interface footprint of top connector 210 does not interfere with the docking interface footprint of bottom connector 220, top connector 210 and bottom connector 220 can be installed in a belly-to-belly configuration. Since the low-speed signals of bottom connector 220 are carried through the cable rather than substrate 240, interference does not occur, eliminating the need for an array of press-fit holes in substrate 240 to carry the low-speed signals. Furthermore, the solder tabs and / or alignment pins of bottom connector 220 can be arranged so as not to interfere with the docking interface footprint of top connector 210.

[0071] Figures 25 to 27 FIG is a perspective view of a connector 300 according to a third embodiment of the present invention. Figures 25 to 27 As shown, connector 300 is a dual stack configuration comprising a cage 320 having two connector bodies 330 and 335 mounted on a substrate 340. The addition of a second connector system increases the available contacts for connecting and routing signals (i.e., high frequency, low frequency, control signals, power, ground, etc.).

[0072] The bottom connector body 335 may be similar to the connector body described above, but without the control PCB. The bottom connector body 335 may carry high speed signals via cables and may carry some or all of the low speed signals via spacers 390 to the control PCB 360 and PCB cable 361 on top of the top connector body 330. Any low speed signals that are not carried to the control PCB 360 may be carried to the substrate 340. The bottom connector body 335 may include contacts having press fit tails that may mate with vias in the spacers 390. The top connector body 330 may also be similar to the connector body described above and may include the control PCB 360 with the PCB cable 361. Crimping may also be used instead of the control PCB 360 so that the PCB cable 361 is crimped to the contacts, as in Figure 18 and Figure 19 The top connector body 330 can include contacts with press-fit tails that can also mate with vias in the spacer 390. The top connector body 330 can also have contacts without press-fit tails that provide an electrical path between the top connector body 330 and the control PCB 360 without passing through the spacer 390.

[0073] Figure 26 A top-down perspective view of Figure 27 The exploded view of FIG shows the connector 300 without the cage 320. The top connector body 330 includes a cable 331 and a control PCB 360 with a PCB cable 361. The bottom connector body 335 can be attached directly to the substrate 340. Figure 26 A spacer 390 is shown, which serves as a mounting structure between the top connector body 330 and the bottom connector body 335. For clarity, the spacer 390 is shown as transparent so that the vias 391 between the top connector body 330 and the bottom connector body 335 can be seen. The spacer 390 can connect some low-speed signals together, and the spacer can connect the ground and / or power from both the top connector body 330 and the bottom connector body 335 together. For example, the ground contacts of the top connector body 330 and the bottom connector body 335 can be connected together by connecting to the same via in the spacer 390.

[0074] Routing some or all of the low speed signals of the top connector body 330 and the bottom connector body 335 through the spacer 390 enables a belly-to-belly configuration, where another connector can be connected on the surface of the substrate 340 opposite the surface on which the connector 300 is mounted, similar to e.g. Figures 20 to 24 Configuration shown.

[0075] Figures 28 to 32 FIG is a perspective view of a connector 400 according to a fourth embodiment of the present invention. Figures 28 to 30 As shown, connector 400 has a belly-to-belly configuration including two cages 410 and 415 with the bottoms of respective connector bodies 430 and 435 mounted on a substrate 440. The addition of a second cage and connector system increases the available contacts for connecting and carrying signals (i.e., high frequency, low frequency, control signals, power, ground, etc.).

[0076] Connector bodies 430 and 435 may be similar to those described above, but may not include a control PCB with cables. Figure 30 and Figure 32 As shown, the contacts 437 of the connector body 430 may be oriented to be mounted to the substrate 440 rather than to the control PCB. Figure 31 As shown in the footprint of FIG, when the contacts 437 are mounted to the substrate 440, the contacts 437 and alignment pins 438 can be arranged so that the array of holes required by the press-fit tails of the contacts 437 and the alignment pins 438 do not interfere with the footprint of the top connector 435. Figure 31 , the footprint of the top connector body 435 on the base plate 3114 is shown in dashed lines and includes connection pads 3116. Holes 3118 for mounting the top connector body 435 and cage 415 are shown in solid lines, while holes 3119 for mounting the bottom connector body 430 and cage 410 are shown in dashed lines.

[0077] Figure 33 is a diagram showing the assembly method of an integrated substrate or PCB. For example, Figure 33 The method shown is to assemble a PCB, the PCB including attaching to the PCB Figure 4 and Figure 5 The connector shown in .

[0078] As shown in step 1, before attaching the connector, electrical components (such as ICs, capacitors, etc.) can be attached to the PCB using a standard reflow soldering process. That is, the electrical components can be surface mounted components. However, alternatively, the electrical components can be attached to the PCB using a press-fit connection. As shown in step 2, the connector is then press-fitted to the PCB. In step 2, the IC connector can also be press-fitted to the PCB. Press-fitting the connector(s) to the PCB can provide sufficient electrical and mechanical connections between the connector(s) and the PCB to ensure that the connector(s) are mechanically fixed to the PCB and provide a low-loss path between the contacts of the connector and the corresponding mounting holes of the PCB.

[0079] By using a press-fit connection to connect the connector(s) to the PCB, the connector(s) and the cable do not need to be compatible with the reflow process. Therefore, a variety of materials can be used to form the connector and the cable, including materials that are not suitable for the reflow process. However, instead of the press-fit connection, other types of connections can be used to attach the connector(s) to the PCB, including fusible connections such as, for example, welding. In addition, the connector can use the same solder as that used to assemble the PCB. Specifically, the connector can be attached to the PCB as a surface mounted component instead. As shown in step 3, the cage is then press-fitted to the PCB.

[0080] In addition, you can Figure 33 Before, during, between, or after any of the steps shown, other components, such as heat sinks, are added to the integrated PCB.

[0081] The embodiments of the present invention described above are compatible with the QSFP specification. That is, the connector according to an embodiment of the present invention can be a female connector or a card edge connector that can be docked with a male connector or a card connector (such as a QSFP type transceiver). However, the connector according to an embodiment of the present invention does not necessarily include a connection to a substrate or PCB that complies with the QSFP specification. According to the QSFP specification, each contact included in the female QSFP connector is directly connected to a corresponding pad on the substrate or PCB. The pad on the substrate or PCB is then connected to a trace formed in the substrate or PCB. In contrast, according to an embodiment of the present invention, some contacts within the QSFP connector are directly docked to the substrate or PCB, while the remaining contacts are docked to the shielded cable.

[0082] Therefore, by transmitting specific signals (such as high-frequency signals) through shielded cables rather than through substrate or PCB traces, board layout flexibility, high bandwidth, and low crosstalk are reliably achieved. In addition, by using shielded cables for high-frequency signals, high signal integrity is maintained, making it possible to use long transmission paths to components (such as ICs) mounted on substrates or PCBs.

[0083] For example, compared to a conventional QSFP connector having a total data transmission rate of 40 Gbits / second, a QSFP connector according to an embodiment of the present invention provides a total data transmission rate of 100 Gbits / second or faster. Specifically, according to an embodiment of the present invention, a data transmission rate of 28 Gbits / second (Gbit / s) can be achieved in each of the four channels.

[0084] Furthermore, because the high frequency signal is transmitted through the shielded cable rather than through traces in the substrate, the substrate does not need to be made of special materials. That is, since the high frequency signal is transmitted through the shielded cable, the dielectric properties of the substrate are not critical, so the substrate can be made of, for example, standard PCB materials (such as FR-4). In addition, the substrate can be made of other materials, such as Panasonic Inc.'s Megtron TM , Park Electrochemical Corp.'s Nelco TM Rodgers of Sunstone Circuits Inc. TM and other suitable materials.

[0085] Specifically, embodiments of the present invention can be configured for use with the QSFP+28 specification to supplement the SFF-8672 specification for a small form-factor pluggable connector system operating at 28 Gigabits per second. Embodiments of the present invention can also be applied to other speed grades including QSFP+14, QSFP+10, QSFP+, and QSFP-DD, which are defined by the SFF-8672, SFF-8682, SFF-8436, and QSFP-DD hardware specifications (Revision 5.0 specifications) for QSPF double-density 8x pluggable transceivers, respectively. These specifications represent a class of backward-compatible, modular pluggable connector systems that provide improved performance for each descendant series. Embodiments of the present invention can be applied to any of these specifications and can be compatible with future higher-speed specifications and applications.

[0086] Furthermore, embodiments of the present invention are not limited to QSFP+ related specifications and systems, and may also be applied to similar pluggable module systems, such as CXP and HD, which are defined by the SFF-8647 specification and the SFF-8644 specification, respectively.

[0087] Cables can include a variety of different wire gauges for the cable's conductors. However, cables can have conductor gauges between 24AWG and 34AWG. Cables with lower-gauge conductors have lower flexibility but lower transmission losses, while cables with higher-gauge conductors have higher flexibility but higher transmission losses. Therefore, applications with higher data transfer rates may benefit from the use of lower-gauge cables because they have lower transmission losses. However, if lower data transfer rates are acceptable, higher-gauge cables can be used to allow for greater IC layout flexibility and overall PCB layout flexibility.

[0088] Since matching impedance reduces unwanted reflections of high frequency signals, the characteristic impedance of the cable is selected to match the impedance of the docking component. The impedance value of the cable can be, for example, in the range of about 80Ω to about 100Ω.

[0089] According to an embodiment of the present invention, a high-speed cable can be directly attached to an IC, rather than being connected to the IC via a PCB. An interconnect can be included between the high-speed cable and the IC, rather than via a PCB. Embodiments of the present invention can be applied to any system currently in use or under development that requires the transmission of high-bandwidth data from a connector to an IC. According to an embodiment of the present invention, an integrated PCB assembly can be used as a line card, motherboard, PCB control, or other component in a digital electronic system. Embodiments of the present invention can be used in conjunction with various data transmission formats, including, for example, InfiniBand, Gigabit Ethernet, Fibre Channel, SAS, PCIe, XAUI, XLAUI, XFI, and other applicable data transmission formats.

[0090] Although the embodiments of the present invention have been described above, it should be understood that changes and modifications will be apparent to those skilled in the art without departing from the scope and spirit of the invention. Therefore, the scope of the present invention is determined only by the appended claims.

Claims

1. A connector system, characterized in that: include: base substrate; a first connector connected to the first surface of the base substrate, and comprising: a first housing including a first contact directly connected to the base substrate in a first region; and a first cage surrounding the first housing; and a second connector connected to a second surface of the base substrate opposite to the first surface, and comprising: a second housing including a second contact directly connected to the base substrate in a second region; additional second contacts, each of the additional second contacts including a portion extending upwardly from an outermost surface of the second housing, the outermost surface being located on a side of the second housing opposite to a side connected to the base substrate, and a second enclosure surrounding the second housing; wherein In a horizontal plane projection view relative to the base substrate, the first region and the second region do not overlap.

2. The connector system according to claim 1, wherein: The first connector and the second connector are compatible with the QSFP specification.

3. The connector system according to claim 1 or 2, characterized in that: In a horizontal plane projection, part of the second enclosure does not overlap with the first enclosure.

4. The connector system according to claim 1 or 2, characterized in that: The second connector also includes a cable directly connected to the additional second contact within the second housing.

5. The connector system according to claim 1 or 2, characterized in that: The first region is defined by all contacts in the first housing that directly contact the base substrate, and The second region is defined by all contacts in the second housing that directly contact the base substrate.

6. The connector system according to claim 1 or 2, characterized in that: In a horizontal plane projection, the first enclosure completely surrounds the first shell, and In a horizontal plane projection, the second enclosure completely surrounds the second shell.

7. The connector system according to claim 1 or 2, characterized in that: In a horizontal plane projection, the first cage completely surrounds the first contact member, and In a horizontal plane projection, the second cage completely surrounds the second contact piece.

8. The connector system according to claim 1 or 2, characterized in that: The first connector includes only surface mount contacts, and The second connector includes only press-fit contacts that are directly connected to the base substrate.

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