This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2013-111263 filed on May 27, 2013, the entire contents of which are incorporated herein by reference.
The embodiments discussed herein are related to a connector.
A related-art connector that includes a transmission line assembly and a housing, in which the transmission line assembly is housed, is used. The transmission line assembly of this connector includes a plurality of insert-molded signal contact components and a metal ground contact. The insert-molded signal contact components include signal contacts and insulating members that hold the signal contacts. The metal ground contact is disposed between the adjacent insert-molded signal contact components. The transmission line assembly of the connector also includes a pair of metal ground plates secured to the ground contact such that electrical conduction is established between the ground plates and the ground contact and the ground contact disposed between the insert-molded signal contact components is clamped by the ground plates.
The following is a reference document.
[Document 1] Japanese Laid-open Patent Publication No. 2004-103527.
According to an aspect of the invention, a connector includes: a casing; a pair of signal terminals that have respective tip end portions, the pair of signal terminals projecting from the casing, the tip end portions being perpendicularly bent; a ground terminal arranged such that the ground terminal and the pair of signal terminals are arranged in a row, the ground terminal projecting at a position adjacent to the pair of signal terminals; and a shield disposed between the casing and the tip end portions of the pair of signal terminals.
The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed.
Before describing embodiments, to which a connector according to the present application is applied, a connector according to an underlying technology of the embodiments is described.
As illustrated in
The through holes 6 are formed in the board 5. The through holes 6 are formed by, for example, making through holes in the board 5 and forming a copper plating film on an inner wall of each of the through holes. The inner diameter of the through holes 6 are set to be slightly smaller than the width of the press-fit pins 2. Thus, the press-fit pins 2, which is press fitted from above in
The press-fit pin 2 having been press fitted into the through hole 6 is in a state illustrated on the left in
The lower halves of the through holes 6 not connected to the respective press-fit pins 2 as described above serve as stubs for signals transmitted to the press-fit pins 2 and may become the sources of noise. Thus, as illustrated on the right in
Since the press-fit pins 2 are easily mounted, press-fit type connectors are used in many cases in particular for backplanes through which signals are transmitted at high-speed.
Connectors such as so-called Dual-In-Line Plug (DIP) connectors are inserted into the through holes 6 and, in this inserted state, subjected to soldering. Compared to such connectors, press-fit type connectors such as the press-fit connector 1 realize desirable manufacturing quality.
The press-fit type connectors such as the press-fit connector 1, the price of which are lower than that of surface mount technology (SMT) type connectors, have become widely used for the backplanes.
However, the press-fit pins 2 are not soldered. Thus, in order to reliably maintain the strength of the board 5 and the through holes 6, connecting portions where the press-fit pins 2 and the respective through holes 6 are connected to one another usually have a certain length (length in the axial direction of the through hole 6).
Furthermore, when connecting the press-fit pins 2 and the through holes 6 to one another, an allowance is usually provided by considering a shift in position or the like in the thickness direction of the board 5 (axial direction of the through holes 6).
For this reason, the length of the connecting portions where the through holes 6 and the respective press-fit pins 2 are in contact with one another, the length being indicated by arrow A on the right side of the press-fit pin 2 illustrated on the right side in
As described above, the connection portions where the press-fit pins 2 and the through holes 6 are connected to one another usually have a certain length. Furthermore, in each through hole 6, there are portions where the through hole 6 is not connected to the press-fit pin 2 on the upper and lower side of the through hole 6 when the press-fit pin 2 and the through hole 6 are connected to one another.
Accordingly, when the speed of a signal transmitted through the press-fit connector 1 is increased to a certain high-speed, the upper and lower portions of the through holes 6, the portions being not connected to the press-fit pins 2, serve as stubs, which become the source of noise. That is, the upper and lower portions of the through holes 6, the portions being not connected to the press-fit pins 2, become the source of noise due to electrical slack.
Furthermore, a tip end 2A of the press-fit pin 2 on the right side in
Presently, the limit of the transmission speed of a signal that may be transmitted through the press-fit connector 1 is about 25 Gbps.
For this reason, the press-fit connector 1 is not suitable for signal transmission in an ultra-high speed range, the signal transmission speed of which exceeds, for example, 25 Gbps.
However, crowd computing, smartphones, and the like have become increasingly popular, and accordingly, the amount of information handled by servers or network equipment are increasing. Thus, there is a large demand for increasing the signal transmission speed.
Nowadays, discussion of ultra-high speed transmission (for example, equal to or higher than 40 Gbps) has been started.
Accordingly, the following embodiments are aimed at providing a connector having desirable electrical characteristics usable for ultra-high speed transmission.
The embodiments, to which the connector according to the present application is applied, are described below.
Out of
As illustrated in
Ten chiclets 110 and ten shield plates 120 are designed such that each of the chiclets 110 is paired with a corresponding one of ten shield plates 120. In each of the pairs, the chiclet 110 is stacked on the shield plate 120 on the positive Z direction side of the shield plates 120.
As illustrated in
As illustrated in, for example,
Ten SMT terminals 111 are each connected to a corresponding one of ten contacts 112. The SMT terminals 111 and the contacts 112 are exposed from the molded resin portion 113 when secured by the molded resin portion 113, which is formed by insert molding.
The chiclets 110 may be produced, for example, as follows: The molded resin portion 113 is formed by molding resin around a lead frame, which includes the SMT terminals 111 and the contacts 112, in an insert molding process, and after that, a frame portion of the lead frame is removed. The lead frame, which includes the SMT terminals 111 and the contacts 112, may be formed by, for example, punching a copper plate.
In the first embodiment, as an example, five pairs of the adjacent SMT terminals 111 and five pairs of the adjacent ten contacts 112 are provided, and differential signals are transmitted through the respective pairs of SMT terminals 111 and the respective pairs of the contacts 112.
As illustrated in
Referring to
It is desirable that the angle by which the tip end portion 111A is bent to the negative Z direction side relative to the base portion 111B be less than 90 degrees. That is, the SMT terminal 111 has a slightly opening right-angled L shape in side view.
The reason for this is to cause the SMT terminals 111 to exert spring elastic forces so that, when moving the connector 100 close to a surface of a board to be connected to the connector 100 in a direction perpendicular to the surface of the board and bringing the tip end portions 111A into contact with pads or the like of the board, the tip end portions 111A are brought into contact with the pads while being pressed against the pads.
The contacts 112 extend from the molded resin portion 113 in the negative X direction. Ten contacts 112 are each connected to a corresponding one of ten SMT terminals 111 in the molded resin portion 113. The contacts 112 are connected to signal input terminals or signal output terminals of an electronic device to which the connector 100 is connected.
Referring to
That is, the contacts 112 may extend in a direction perpendicular to the SMT terminals 111 in plain view (plan view of the XY plane) or in a direction rectilinear (coaxial) with the SMT terminals 111.
The molded resin portion 113 is formed by, for example, molding a thermosetting epoxy resin in an insert molding process. The molded resin portion 113 is a plate-shaped member having a rectangular shape in plain view (plan view of the XY plane).
Ten signal wires are disposed in the molded resin portion 113. In each of ten signal wires, one end is the SMT terminal 111 and the other end is the contact 112. Furthermore, groove portions 113A and rib portions 113B, which respectively correspond to rib portions 120A1 and groove portions 120A2, are formed in a surface of the molded resin portion 113 to be in contact with the shield plate 120. Also in the molded resin portion 113, rib portions 113C and groove portions 113D are formed in a surface on a side opposite to the surface where the groove portions 113A and the rib portions 113B are formed. The positions of the groove portions 113A and the groove portions 113D are shifted from one another in the X direction. Likewise, the positions of the rib portions 113B and the rib portions 113C are shifted from one another in the X direction.
As illustrated in
The plate portion 120A is a rectangular plate-shaped member having the substantially the same size and shape as those of the molded resin portion 113 of the chiclet 110 in plain view (plan view of the XY plane). Six of the press-fit pin 121 and five of the shielding portion 123 are formed in an edge of the plate portion 120A on the negative Y direction side.
The plate portion 120A has six rib portions 120A1 and five groove portions 120A2. The rib portions 120A1 are at positions higher than those of the groove portions 120A2 in the Z direction. The rib portions 120A1 and the groove portions 120A2 are formed in the Y direction.
Six press-fit pins 121 are each connected to a corresponding one of six rib portions 120A1, and five shielding portions 123 are each connected to a corresponding one of five groove portions 120A2.
In other words, six press-fit pins 121 each extend from a corresponding one of six rib portions 120A1 in the negative Y direction, and five shielding portions 123 each extend from a corresponding one of five groove portions 120A2 in the negative Y direction.
The difference in level between the rib portions 120A1 and the groove portions 120A2 in the Z direction is set such that, when the chiclet 110 is stacked on the positive Z direction side of the shield plate 120, the level of the press-fit pins 121 in the Z direction is set at the same level as that of the base portions 111B of the SMT terminals 111 in the Z direction.
The contacts 122 are formed in an edge of the plate portion 120A on the negative X direction side. Referring to
The press-fit pins 121 are formed in an edge of the plate portion 120A on the negative Y direction side. Six press-fit pins 121 and five shielding portions 123 are arranged in an alternating sequence. The press-fit pins 121 are disposed on both sides of five shielding portions 123.
The press-fit pins 121 are connected to ground terminals of the electronic device, to which the connector 100 is connected, through the contacts 122. The press-fit pins 121 each serve as an example of the ground terminal.
The press-fit pins 121 are press fitted into through holes of the board to be connected to the connector 100. In a state in which the press-fit pins 121 have been press fitted into the through holes, press-fitting portions 121A of the press-fit pins 121 are positioned further to the negative Y direction side than the tip ends of the shielding portions 123 in order to avoid contact of the shielding portions 123 with the board connected to the connector 100.
The press-fit pins 121, each of which extends from a corresponding one of the rib portions 120A1 in the negative Y direction, are disposed at positions higher than those of the shielding portions 123 in the Z direction. The reason for this is that, when the chiclet 110 is stacked on the positive Z direction side of the shield plate 120, the level of the press-fit pins 121 in the Z direction is at the same level as those of the base portions 111B of the SMT terminals 111 in the Z direction.
The press-fit pins 121 are each disposed at a position not superposed with corresponding one pair out of five pairs of ten SMT terminals 111 in plain view (plan view of the XY plane).
The contacts 122 are connected to ground terminals of the electronic device to which the connector 100 is connected.
Referring to
That is, the contacts 122 may extend in a direction perpendicular to the press-fit pins 121 and the shielding portions 123 in plain view (plan view of the XY plane) or in a direction rectilinear (coaxial) with the press-fit pins 121 and the shielding portions 123.
The shielding portions 123 each have a tip end portion 123A and a base portion 123B. The base portion 123B of the shielding portion 123 is formed such that the base portion 123B extends in the negative Y direction from an edge of the groove portion 120A2 of the plate portion 120A on the negative Y direction side and is bent in the negative Z direction by 90 degrees. The tip end portion 123A extends in the negative Z direction.
Accordingly, as illustrated in
The difference in level between the rib portions 120A1 and the groove portions 120A2 in the Z direction is set such that, when the chiclet 110 is stacked on the positive Z direction side of the shield plate 120, the level of the press-fit pins 121 in the Z direction is set at the same level as that of the base portions 111B of the SMT terminals 111 in the Z direction.
Thus, when the chiclet 110 is stacked on the positive Z direction side of the shield plate 120, the positions of the press-fit pins 121 in the Z direction is the same as those of the base portions 111B of the SMT terminals 111 in the Z direction.
Furthermore, when the chiclet 110 is stacked on the positive Z direction side of the shield plate 120, the base portions 123B of the shielding portions 123 are located further to the negative Z direction side than the press-fit pins 121 and the base portions 111B of the SMT terminals 111.
Furthermore, the length of the base portions 123B of the shielding portions 123 in the Y direction is set so as to cause the tip end portions 123A to be located further to the positive Y direction side than the tip end portions 111A of the SMT terminals 111 when the chiclet 110 is stacked on the positive Z direction side of the shield plate 120.
The shielding portions 123 are each disposed at a position superposed with corresponding one pair out of five pairs of ten SMT terminals 111 in plain view (plan view of the XY plane). With this structure, the SMT terminals 111 are shielded by the shielding portions 123 when the connector 100 is connected to the board.
The width of each of the shielding portions 123 in the X direction is larger than the width between an end portion on the negative X direction side of the SMT terminal 111 on the negative X direction side out of a corresponding pair of the SMT terminals 111 and an end portion on the positive X direction side of the SMT terminal 111 on the positive X direction side out of the corresponding pair of the SMT terminals 111.
With this structure, when the chiclet 110 is stacked on the positive Z direction side of the shield plate 120, each shielding portion 123 shields a corresponding pair of the SMT terminals 111 by covering the corresponding pair of the SMT terminals 111 in the X direction.
Herein, two SMT terminals 111 are shielded by one shielding portion 123. When one SMT terminal 111 is shielded by one shield, it is sufficient that the width of the shielding portion 123 be larger than the width of one SMT terminal 111.
When three or more SMT terminals 111 are shielded by one shield, it is sufficient that the width of the shielding portion 123 be larger than the following width: the width between an end portion on the negative X direction side of the SMT terminal 111 on the most negative X direction side out of three or more SMT terminals 111 to be shielded by this shielding portion 123 and an end portion on the positive X direction side of the SMT terminal 111 on the most positive X direction side out of the three SMT terminals 111.
Next, with reference to
In
Here, in
A surface 100A is parallel to the XZ planes of ten pairs of the chiclet 110 and the shield plate 120 (ten chiclets 110 and ten shield plates 120). As illustrated in
The surface 100A is formed by end surfaces of the molded resin portions 113 included in ten chiclets 110 and end surfaces of the plate portions 120A included in the ten shield plates 120. The surface 100A serves as an example of a surface of the casing of the connector 100 according to the first embodiment.
The SMT terminals 111 included in ten chiclets 110 extend from the surface 100A in the negative Y direction and are bent to the negative Z direction side.
The angle by which the tip end portions 111A are bent from the base portions 111B of the SMT terminals 111 to the negative Z direction side is less than 90 degrees. As illustrated in
Furthermore, because of the difference in level in the Z direction between the rib portions 120A1 and the groove portions 120A2 of the shield plate 120 (see
Furthermore, the press-fit pins 121 included in ten shield plates 120 extend from the surface 100A in the negative Y direction.
The shielding portions 123 included in ten shield plates 120 extend from the surface 100A in the negative Y direction and are bent to the negative Z direction side.
More specifically, in each of the shielding portions 123, the base portion 123B is formed such that the base portion 123B extends in the negative Y direction from the edge of the groove portion 120A2 of the plate portion 120A on the negative Y direction side and is bent in the negative Z direction by 90 degrees, and the tip end portion 123A extends in the negative Z direction.
For this reason, the base portions 123B of the shielding portions 123 are located further to the negative Z direction side than the press-fit pins 121 and the base portions 111B of the SMT terminals 111.
Furthermore, the shielding portions 123 are each disposed at positions superposed with a pair of the SMT terminals 111. The width of each of the shielding portions 123 in the X direction is larger than the width between the end portion on the negative X direction side of the SMT terminal 111 on the negative X direction side out of a corresponding pair of the SMT terminals 111 and the end portion on the positive X direction side of the SMT terminal 111 on the positive X direction side out of the corresponding pair of the SMT terminals 111.
The length of the base portions 123B of the shielding portions 123 in the Y direction is set so as to cause the tip end portions 123A to be located further to the positive Y direction side than the tip end portions 111A of the SMT terminals 111 when the chiclets 110 are stacked on the positive Z direction side of the shield plates 120.
Thus, as illustrated in
This means that, in the YZ plane as illustrated in
As described above, in the connector 100 according to the first embodiment, the shielding portions 123 having been bent to have an L-shape are disposed along the SMT terminals 111 having been bent to have an L-shape and each of the shielding portions 123 is disposed near a corresponding pair of the SMT terminals 111.
When the press-fit pins 121 of the connector 100 are press fitted into the through holes of the board to be connected, the surfaces of the tip end portions 111A of the SMT terminals 111, the surfaces located on the negative Y direction side, (upper surfaces in
Here, a state in which the connector 100 according to the first embodiment is connected to a board 5A is described with reference to
Specifically,
As illustrated in
Accordingly, when the SMT terminals 111 of the connector 100 are connected to the pads 6A of the board 5A by an SMT method, introduction of noise or the like into the SMT terminals 111 may be suppressed, and accordingly, impedance matching of the SMT terminals 111 may be improved. As a result, signal transmission characteristics may be improved.
In
Here, in the simulation, dimensions and so forth are set as follows: the width and height of the SMT terminals 111 are respectively 0.25 mm and 0.175 mm; the interval between a pair of the SMT terminals 111 is 0.75 mm; the interval between SMT terminal 111 and the shielding portion 123 is 0.3 mm; and the distance between the surface of the board 5A to the ground layer 7A (the depth from the surface of the board 5A to the surface of the ground layer 7A) is 0.25 mm. The ground layer 7A uses copper foil disposed on one surface of the board 5A.
The characteristic impedance of the SMT terminals 111 illustrated in
Thus, it is understood that, in the connector 100 according to the first embodiment, which includes the shielding portions 123, the characteristic impedance of the SMT terminals 111 may be significantly improved.
As described above, according to the first embodiment, the connector 100 having improved electrical characteristics may be provided.
For example, the connector 100 according to the first embodiment is usable for ultra-high speed transmission (for example, a transmission speed of equal to or higher than 40 Gbps).
Furthermore, impedance matching of the SMT terminals 111 is improved by the shielding portions 123. This suppresses reflection of signals, and accordingly, the signal transmission characteristics are further improved.
Furthermore, in the connector 100 according to the first embodiment, the press-fit pins 121 are disposed on both sides of each pair of the SMT terminals 111. That is, the press-fit pins 121, which are held at the ground potential, are disposed near both sides of each pair of the SMT terminals 111, through which high-speed differential signals are transmitted.
Thus, in the connector 100 according to the first embodiment, introduction of noise or the like into a single pair of the SMT terminals 111 may be suppressed by the press-fit pins 121. This may further improve impedance matching of the SMT terminals 111.
Furthermore, in the connector 100 according to the first embodiment signal transmission terminals use the SMT terminals 111. Unlike the press-fit pins 2 according to the underlying technology (see
Thus, in the connector 100 according to the first embodiment, compared to a case such as a case with the underlying technology where the press-fit pins 2 (see
Also in the connector 100 according to the first embodiment, the angle by which the tip end portions 111A are bent from the base portions 111B of the SMT terminals 111 to the negative Z direction side is less than 90 degrees, and the SMT terminals 111 have a slightly opening right-angled L shape in side view.
Thus, by causing the SMT terminals 111 to exert spring elastic forces when moving the connector 100 close to the surface of the board 5A in a direction perpendicular to the surface of the board 5A and bringing the tip end portions 111A into contact with the pads 6A, the tip end portions 111A are brought into contact with the pads 6A while being pressed against the pads 6A.
Accordingly, properties of the tip end portion 111A for connection with the pads 6A may be further improved. Thus, when the solder 150, by which the tip end portions 111A of the SMT terminals 111 are joined to the pads 6A, is not desired, the joining may be performed without the solder 150.
The reason for this is that the board 5A and the connector 100 are secured to each other by the press-fit pins 121 and the through holes 6B.
Actually, a number of SMT terminals 111 are provided corresponding to a number of pads 6A of the board 5A. There may be variation in height of the pads 6A of the board 5A.
Thus, particularly when the angle by which the tip end portions 111A are bent from the base portions 111B of the SMT terminals 111 to the negative Z direction side is less than 90 degrees, variation in height of the pads 6A may be addressed, and accordingly, so-called coplanarity may be improved.
Although the shield plate 120 includes the press-fit type press-fit pins 121 in the above description, the shield plate 120 may include SMT terminals as illustrated in
As illustrated in
The SMT terminals 121C may be connected to the pads of the board 5A without using the screws 160.
Alternatively, the SMT terminals 111 of the chiclets 110 may be secured by the screws 160.
Although the angle by which the tip end portions 111A are bent from the base portions 111B of the SMT terminals 111 to the negative Z direction side is less than 90 degrees in the above description, the angle by which the SMT terminals 111 are bent may be 90 degrees.
In the above description, as illustrated in, for example,
Alternatively, the SMT terminals 111, the contacts 112, the plate portion 120A, the press-fit pins 121, the contacts 122, and the shielding portions 123 may be secured to a single casing in an insert molding process.
The connector 200 according to the second embodiment is similar to the connector 100 according to the first embodiment except for the structure of the shielding portions 223, which is different from that of the shielding portions 123 of the first embodiment.
Accordingly, elements of the connector 200 similar to those of the connector 100 according to the first embodiment are denoted by the same reference signs and description thereof is omitted.
The shielding portions 223 each have a tip end portion 223A, which corresponds to the tip end portion 123A of the shielding portion 123 of the first embodiment. As illustrated in
Thus, introduction of noise or the like into the SMT terminals 111 may be more effectively suppressed by the shielding portions 223, and accordingly, impedance matching of the SMT terminals 111 may be further improved.
The molded resin portions 113 of the chiclets 110 A of the connector according to the third embodiment have standoffs 370. The structure of the connector according to the third embodiment is similar to that of the connector 100 according to the first embodiment except for the standoffs 370. Thus, elements of the connector according to the third embodiment similar to those of the connector 100 according to the first embodiment are denoted by the same reference signs and description thereof is omitted.
The standoffs 370 are provided to avoid the occurrence of a situation in which the press-fit pins 121 are excessively inserted (excessively press fitted) into the through holes 6B of the board 5A (see
It is sufficient that the standoffs 370 are formed, for example, on a side surface of the molded resin portion 113 illustrated in
It is sufficient that the height of the standoffs 370 is, as illustrated in
As described above, according to the third embodiment, the connector which has improved electrical characteristics and with which excessive press-fitting is suppressed during mounting, is provided.
All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiments of the present invention have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.
Number | Date | Country | Kind |
---|---|---|---|
2013-111263 | May 2013 | JP | national |