1. Field of the Invention
The present invention relates to electrical connector technology and more particularly, to such an electrical connector, which achieves optimal impedance matching and high structural stability, ensuring high signal transmission quality and reliability.
2. Description of the Related Art
Following fast development of computer technology, high mobility notebook computer has been well developed and widely used by people to substitute for desk computer. Further, when connecting a computer to a peripheral apparatus for transmitting data or signal, a peripheral interface means is necessary. USB (universal serial bus) is the mainstream interface, having hot plug function.
Further, following the market trend to make computers and peripheral devices having a small size characteristic, the problem of internal signal interference due to magnetic effects must be taken into account. Interferences may come from conducted disturbance that occurs during signal transmission through power circuits and/or signal lines of the circuit board to the electrical connector, or radiated disturbance that occurs due to the radiation of magnetic waves around the electrical connector. As a USB 3.0 connector uses a large number of conducting terminals that are arranged in a limited mounting area, approaching between two conducting terminals or curving of any conducting terminal may cause disturbance (static interference, electromagnetic interference, impedance matching, noise interface, crosstalk interference) during the transmission of a high-frequency signal. Further, EMI (electromagnetic interference) and noises can be eliminated or reduced during signal transmission between a USB 3.0 connector and a system mainboard interface only if impedance matching condition is satisfied. Improper impedance matching can cause signal reflection and noise interference, resulting in signal loss, signal deformation and/or signal distortion. When this problem occurs, the electronic system (computer or network system) may be unable to function normally.
Further, a circuit board design of tongue plate has copper foil contacts arranged on a plane. For example, an HDMI socket connector is based on this design. Further, a circuit board design of tongue plate for USB 3.0 female connector has 5 pcs of copper foil contacts and 4 pcs of springy metal contact terminals. When a USB 3.0 male connector is inserted into a USB 3.0 female connector, the arrangement of the springy metal contact terminals at the circuit board design of tongue plate of the USB 3.0 female connector may causes serious mechanism problems. The first problem is that the positioning of the front contact portions of the springy metal contact terminals on the top side of the circuit board design of tongue plate may be directly impacted by the mating metal contact terminals of the USB 3.0 male connector, due to positioning displacement or large tolerance, causing disconnection of the spring metal contact terminals from the circuit board design of tongue plate. The second problem is that the springy metal contact terminals may be squeezed toward the circuit board design of tongue plate by a lateral force upon insertion of the USB 3.0 male connector into the USB 3.0 female connector, causing damage or disconnection of the rear soldering portions of the springy metal contact terminals from the circuit board design of tongue plate. A third problem is that the circuit board design of tongue plate has no room for allowing the springy metal contact terminals to be elastically and heavily deformed and the springy metal contact terminals may be permanently deformed.
Therefore, it is desirable to provide an electrical connector, which eliminates the aforesaid problems.
The present invention has been accomplished under the circumstances in view. It is therefore the main object of the present invention to provide an electrical connector, which achieves optimal impedance matching and high structural stability, ensuring high signal transmission quality and reliability.
To achieve this and other objects of the present invention, an electrical connector comprises an electrically insulative holder member, a signal module mounted in the holder member, and a metal shield surrounding the holder member and the signal module. The electrically insulative holder member comprises a holder base, and a tongue plate suspending in the front side of the holder base. The tongue plate comprises at least one opening in the bottom side thereof and five contact holes arranged in a transverse line in a front side relative to the at least one opening. The signal module comprises a circuit board, which comprises a plurality of longitudinal terminal holes, a plurality of circuit lines, a plurality of electrical contacts and a plurality of via-holes, a plurality of metal contact terminals, and a plurality of metal mounting terminals. The metal contact terminals are respectively mounted in the circuit board corresponding to the longitudinal terminal holes, each comprising a rear soldering end portion electrically soldered to one circuit line, a front contact portion positioned in the front end of one respective longitudinal terminal hole, and a suspension arm obliquely downwardly extending from the rear soldering end portion and terminating in the front contact portion below the associating longitudinal terminal hole. The metal mounting terminals are respectively soldered to the via-holes of the circuit board.
As the circuit board is accommodated in the tongue plate, when a mating connector is inserted into the metal shield, the direct impact by the mating connector is avoided.
Further, the surface area of the circuit lines of the circuit board may be configured subject to different impedance matching requirements, enhancing signal transmission quality and reliability.
Further, an electronic component, such as common-mode choke coil, filter resistor or filter capacitor may be installed in the circuit lines of the circuit board for removing noises, enhancing signal transmission quality and reliability.
Reference will be made in detail to the preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings. Wherever possible, like reference numbers are used in the drawings and the description to refer to like parts.
Referring to
The electrically insulative holder member 1 comprises a holder base 11, a tongue plate 12, and a partition block 13. The holder base 11 defines an accommodation open chamber 10 in the rear bottom side thereof, and two inside retaining flanges 111 symmetrically disposed at two opposite lateral sides in the accommodation open chamber 10. The tongue plate 12 suspends in the front side of the holder base 11, defining an insertion chamber 120 therein, at least one opening 121 in a bottom side thereof in communication with the insertion chamber 120, five contact holes 122 in a transverse line in front of the at least one opening 121, a recess 1201 at a rear side relative to the insertion chamber 120, and a vertical stop edge 123 extending around top and opposing lateral sides of the recess 1201. The partition block 13 defines a plurality of through holes 131 vertically cut through opposing top and bottom sides thereof and arranged in two lines, and two coupling flanges 132 symmetrically disposed at two opposite lateral sides corresponding to the inside retaining flanges 111 of the holder base 11.
The signal module 2 comprises a horizontally extending circuit board 21, a plurality of metal contact terminals 22, and a plurality of metal mounting terminals 23. The circuit board 21 defines therein a plurality of longitudinal terminal holes 210, a plurality of circuit lines 211, a plurality of electrical contacts 212, and a plurality of via-holes 213. The metal contact terminals 22 are respectively set in the longitudinal terminals holes 210 of the circuit board 21, each comprising a rear soldering end portion 221 electrically soldered to one respective circuit line 211 at the circuit board 21, a front contact portion 223 respectively positioned in the front end of one respective longitudinal terminal hole 210, and a suspension arm 222 obliquely downwardly extending from the rear soldering end portion 221 toward the front contact portion 223 below the longitudinal terminal hole 210, and an oblique contact face 2231 connected between the front contact portion 223 and the suspension arm 222. According to this embodiment, the metal contact terminals 22 are configured subject to USB 2.0 specification, i.e., the number of the metal contact terminals 22 is 4; the electrical contacts 212 are configured to match with the metal contact terminals 22 subject to USB 3.0 specification, i.e., the number of the electrical contacts 212 is 5; the electrical contacts 212 and the front contact portion 223 are respectively arranged in a respective line in a staggered manner; the number of the via-holes 131 is 9, i.e., four via-holes 131 are arranged in a first line at the front side and the other five via-holes 131 are arranged in a second line at the rear side. Further, the metal contact terminals 22 and the electrical contacts 212 are respectively electrically connected to the via-holes 213 by the circuit lines 211. The metal mounting terminals 23 are respectively soldered to the via-holes 213 and vertically downwardly extended from the circuit board 2.
Further, the rear soldering end portions 221 of the metal contact terminals 22 and the metal mounting terminals 23 are respectively soldered to the circuit board 21 by SMT (surface mounting technology) and through-hole technology. However, this mounting arrangement is not a limitation. SMT (surface mounting technology) and through-hole technology may be selectively employed to solder the rear soldering end portions 221 of the metal contact terminals 22 and the metal mounting terminals 23 to the circuit board 21 subject to different design requirements. Further, the circuit board 21 can be a single layer board, or multi-layer board. Further, the metal contact terminals 22 may be variously embodied with the suspension arm 222 and/or the front contact portion 223 multiply curved to disperse stress when the metal contact terminals 22 are compressed, avoiding deformation, displacement or damage.
The metal shield 3 comprises a front receiving hole 31, a rear accommodation chamber 32 disposed in communication with the front receiving hole 31, and two bottom mounting legs 33 respectively downwardly extended from two opposite lateral sides thereof.
Referring to
Referring to
Referring to
Referring to
Further, a USB 3.0 connector must match the impedance (Z) of the system mainboard interface. EMI and noises can be eliminated or reduced for allowing accurate signal transmission between the USB 3.0 connector and the system mainboard interface only when impedance matching condition is satisfied.
Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.
Number | Name | Date | Kind |
---|---|---|---|
7699663 | Little et al. | Apr 2010 | B1 |
7736184 | Wan et al. | Jun 2010 | B1 |
7794284 | He et al. | Sep 2010 | B1 |
7806704 | Miyoshi et al. | Oct 2010 | B2 |
7837510 | Hung et al. | Nov 2010 | B1 |
7862346 | Wan et al. | Jan 2011 | B1 |
7927145 | Chang | Apr 2011 | B1 |
8408940 | Chang | Apr 2013 | B2 |
8449205 | Little et al. | May 2013 | B2 |
20050106939 | Zhang et al. | May 2005 | A1 |
20060025015 | Hu et al. | Feb 2006 | A1 |
20070066102 | Takemoto et al. | Mar 2007 | A1 |
20080166918 | Yang et al. | Jul 2008 | A1 |
20120077370 | Lee et al. | Mar 2012 | A1 |