1. Field of the invention
The present invention relates to an electrical connector, and particularly to a high density backplane connector in which contact engaging portions of a male connector are arranged in first and second columns, and while a mating intersection of a receptacle connector is also arranged in first and second columns corresponding to the second and first columns of the contact engaging portions, respectively.
2. Description of Related Art
Backplane connector is generally configured with a wafer on which about four contacts, say first, second, third and fourth contacts are arranged in a single plane. For explanation, the first contact will referred to the contact closer to a motherboard, while the fourth contact will be the contact most distant to the mother. Since those four contacts are generally arranged in right-angle, the overall length of those four contacts vary accordingly, i.e. the first contact has the shortest overall length, while the fourth contact has the longest overall length. As a result, a single skew will be encountered. The same applies to a differential pairs are well since the contact lengths are different from each other within the pairs when it is arranged in right-angle.
The right angle configuration of the typical backplane connector provides variable lengths in signal transmission paths. The paths go from shortest to longest as contacts move further away from the component side of the daughter board. Signal launched at the same time would arrive at different times at the far end of the connector due to the difference in length, or skew, of the transmission paths. In a differential pair configuration, this difference in length, or skew, must be compensated for and is typically handled by the PCB designer. Some connectors are designed to provide skew compensation by adding air in the areas where the transmission paths bend on the longer path of the two paths within the differential pair. This allows the signal to travel faster around the bends of the longer path in an attempt to get the signals to arrive at the same time at the far end. The typical connector is described either in U.S. Pat. No. 7,229,318 issued to Winings et al. on Jun. 12, 2007 or U.S. Pat. No. 7,390,218 issued to Smith et al. on Jun. 24, 2008.
However, this method would have a detrimental effect impedance and increased crosstalk.
An object of the present invention is to provide a high density backplane connector having improved effect of reducing crosstalk by providing substantially equal signal transmission paths among the contacts.
To achieve the aforementioned objects, a high density backplane connector includes a group of terminal pairs and a group of contact pairs arranged along a first direction. Each terminal pair includes a first terminal and a second terminals substantially aligned with each other along a second direction perpendicular to the first direction. The first terminal has a first engaging portion and a first tail portion. The second terminal has a second engaging portion and a second tail portion. The first and second tail portions of the terminal pairs disposed in a line and designated as signal-signal-ground sequence. The contact pairs include a first and a second contacts substantially aligned with each other along the second direction. The first contact has a first tail portion and a first contact portion in contact with the second engaging portion of the second terminal. The second contact has a second tail portion and a second contact portion in contact with the first engaging portion of the first female terminal. The first and second tail portions of the contact pairs disposed in a line. A length of the first terminal plus a length of a corresponding mated second contact is substantially equal to a length of the second terminal plus a length of a corresponding mated first contact.
Signals transmitted through the first transmission path of the second contact and the first terminal, and the second transmission path of the first contact and the second terminal. Designing the twist transmission paths within the wafer or dielectric support allows signals travel through the high density backplane connector synchronously. It helps to reduce crosstalk by eliminating skew on the terminals or the contacts.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of a preferred embodiment when taken in conjunction with the accompanying drawings.
Reference will now be made to the drawing figures to describe the present invention in detail. Referring to
Referring to
Referring to
Referring
In assembling of the first female terminal module 10a, the plurality of first female terminals 12 are mounted in the first female dielectric support 11 firstly, with the first connecting portion 123 embedded in the first female dielectric support 11. The first grounding terminals 121 and the first signal terminals 122 are disposed alternately with each other.
Secondly, the second female terminals 14 are embedded in the second female dielectric support 13 by insert molding or other methods, with the second engaging portion 144 exposed on the second female dielectric support 13 and the tail portion 145 exposed outside of the second female dielectric support 13. The second grounding terminals 141 and the second signal terminals 142 are disposed alternately with each other. The second female dielectric support 13 defines a plurality of grooves or recesses 131 aligned with the second engaging portion 144.
Thirdly, the first female dielectric support 11 together with the first female terminals 12 are mounted on the second female dielectric support 13 together with the second female terminals 14 to form the first female terminal module 10a as a whole.
At the same time, the tail portions 125 and 145 of the first grounding terminal 121 and the second grounding terminal 141 are disposed in oppose pattern to form themselves as a grounding terminal pair 17. The first grounding terminal 121 and the second grounding terminal 141 are substantially aligned with each other along a traverse direction perpendicular to the vertical direction. The tail portion 125 and 145 of the first signal terminal 122 and the second signal terminal 142 are disposed in jogged pattern to form themselves as a signal terminal pair 18. The first signal terminal 122 and the second signal terminal 142 are substantially aligned with each other along the traverse direction.
The first female terminal module 10a has a mating edge 101 for mating with the male connector 2. In each first female terminal module 10a, compared to the first engaging portions 124 of the first female terminals 12, the second engaging portions 144 of the second female terminals 14 are disposed adjacent to the mating edge 101. The first tail portion 125 of the first grounding terminal 121 and the tail portion 145 of the second grounding terminal 141 are overlapped with each other (see
In conjunction with
Referring to
Referring
In assembling of the first male contact module 20a, the plurality of first male contacts 22 are mounted in the first male wafer 21 firstly, with the first body portion 223 inserted in the first male wafer 21. The first grounding contacts 221 and the first signal contacts 222 are disposed alternately with each other.
Secondly, the second male contacts 24 are embedded in the second male wafer 23 by insert molding or other methods, with the second contact portion 244 exposed on the second male wafer 23 and the second tail section 245 exposed outside of the second male wafer 23. The second grounding contacts 241 and the second signal contacts 242 are disposed alternately with each other. The second male wafer 23 defines a plurality of grooves 131 aligned with the second contact portions 244.
Thirdly, the first male wafer 21 together with the first male contacts 22 are mounted on the second male wafer 23 together with the second male contacts 24 to form the first male contact module 20a as a whole.
At the same time, the first grounding contact 221 and the second grounding contact 241 are disposed in opposing pattern to form themselves as a grounding contact pair 27. The first grounding contact 221 and the second grounding contact 241 are substantially aligned with each other along the traverse direction. The tail sections 225, 245 of the first signal contact 222 and the second signal contact 242 are disposed in jogged pattern to form themselves as a signal contact pair 28. The first signal contact 222 and the second signal contact 242 are substantially aligned with each other along the traverse direction.
The first male contact module 20a has a mating side 201 for mating with the first female terminal module 10a. In each first male contact module 20a, compared to the first contact portions 224 of the first male contacts 22, the second contact portions 244 of the second male contacts 24 are disposed adjacent to the mating side 201. The first tail section 225 of the first grounding contact 221 and the second tail section 245 of the second grounding contact 241 are overlapped with each other. The first tail section 225 of the first signal contact 222 and the second tail section 245 of the second signal contact 242 are disposed in sequence. The tail sections 225, 245 of all contacts in one module are designated as ground-signal-signal sequence and substantially arranged in a line.
The second male contact module 20b has a configuration similar to that of the first male contact module 10b, with the terminal arrangement of staggered with that of the first male contact module 20a for reducing crosstalk.
Referring to
The first tail portion 125 of the first grounding terminal 121 and the second tail portion 145 of the second grounding terminal 141 are overlapped with each other to share a first grounding hole 31 of the mother board 3. The first signal terminal 122 and the second signal terminal 142 are formed as a differential terminal pair, i.e., the signal terminal pair 18, with the first tail portion 125 of the first signal terminal 122 and the second tail portion 145 of the second signal terminal 142 inserted into corresponding first signal hole pair 32 of the mother board 3.
The first tail section 225 of the first grounding contact 221 and the second tail section 245 of the second grounding contact 241 are overlapped with each other to share a same second grounding hole 41 of the daughter board 4. The first signal contact 222 and the second signal contact 242 are formed as a differential contact pair, i.e., the signal contact pair 28, with the first tail section 225 of the first signal contact 222 and the second tail section 245 of the second signal contact 242 inserted into corresponding second signal hole pair 42 of the daughter board 4.
The first grounding contact 221 and the second grounding contact 241 respectively electrically connect with the second grounding terminal 141 and the first grounding terminal 121 for grounding. The first signal contact 222 and the second signal contact 242 respectively electrically connect with the second signal terminal 142 and the first signal terminal 122 for transmitting differential signal.
The length of first grounding terminal 121 plus the length of the second grounding contact 241 is substantially equal to the length of second grounding terminal 141 plus the length of first grounding contact 221. Thus, the transmission path of transmitting grounding signals through the path of first grounding terminal 12 land the second grounding contact 241 is equal to that through the path of the second grounding terminal 141 and the first grounding contact 221. The grounding signal launched at the same time would arrive at the same time via the two paths. Similarly, the length of first signal terminal 122 plus the length of the second signal contact 242 is substantially equal to the length of second signal terminal 142 plus the length of first signal contact 222. The differential signal launched at the same time would arrive at the same time through the second signal contact 242 then the first signal terminal 122, and through the first signal contact 222 then the second signal terminal 142. Designing the twist transmission paths within the wafer or dielectric support allows signals travel through the high density backplane connector 100 synchronously.
The grounding path and the signal path are arranged alternately in the high density backplane connector 100. The ratio of grounding path and the signal path is one vs one. It helps to improve crosstalk performance. Optionally, the ratio of the signal path and the grounding path could be increased, with the crosstalk performance being unimproved.
Referring to
Referring to
This patent application is related to a pending U.S. patent application Ser. No. 12/148757, filed on Apr. 22, 2008, and entitled “HIGH DENSITY CONNECTOR HAVING TWO-LEVELED CONTACT INTERFACE”, which is assigned to the same assignee with this application.