WO2004075351A1

WO2004075351A1 - Power interconnect device

Info

Publication number: WO2004075351A1
Application number: PCT/US2004/004135
Authority: WO
Inventors: Russell G. Larsen; Thomas P. Lowes
Original assignee: Tyco Electronics Corporation; Custom Stamping, Inc.
Priority date: 2003-02-13
Filing date: 2004-02-13
Publication date: 2004-09-02
Also published as: JP2006518091A; WO2004075351A9; CN1778019A; CN100384021C; CN1771632A; WO2004075352A1

Abstract

An in-line connector for providing power from a first circuit board to a second circuit board is described. The connector includes a housing and first and second contacts spaced apart from each other with a first insulating member positioned in a space between the contacts. The contacts each have a linear array of a plurality of mating fingers spaced apart along their lengths. The contacts are positioned in the housing such that they are essentially parallel to each other and the mating fingers of the first contact are interdigitated with the mating fingers of the second contact.

Description

Power Interconnect Device

Cross-Reference to Related Applications

[0001] This application claims priority under 35 USC 119 from U.S. Provisional

Application No. 60/447,532, filed February 13, 2003 under 35 USC 111(b). The disclosure of that provisional application is incorporated herein by reference. This application is also related to application Serial No. as yet unknown, attorney docket number ECN052-PCT2, entitled "Power Interconnect Device," filed contemporaneously with this application, the disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

Field of the Invention

[0002] This invention relates to power interconnect devices in general and low inductance power distribution power interconnect devices in particular.

Introduction to the Invention

[0003] Modern electrical systems, designed with increasingly higher density circuitry packaged in smaller form factors, are driving the development of power interconnect solutions intended to deliver more power using less space. This increase in power density occurs both at the system level and at the board level, as seen in existing inter-cabinet, intra- cabinet, and PCB (printed circuit board) to PCB power distribution schemes designed to support more electrical current and power in less space. To meet these requirements, system designers can leverage custom power distribution systems that take advantage of more efficient materials and processes. For example, bus bar-based power distribution schemes and their associated power interconnect solutions are often used.

[0004] At the chip level, the power consumption and current transients of available high performance microprocessors are large and fast, respectively. Therefore, it is desired that the distribution system that supplies power to microprocessors have very low inductance and resistance to minimize voltage disturbances at the chip. A common strategy implemented to reduce inductance and resistance is to move the power source or Voltage Regulator Module (VRM) closer to the load. This method requires a separable power interconnection. Available power connectors generally require large amounts of space to have sufficiently low inductance and low resistance. Therefore, there is a need for power connectors having low inductance with reduced space requirements.

BRIEF SUMMARY OF THE INVENTION

[0005] In a first aspect, this invention provides an in-line interconnect comprising a housing, first and second contacts each having a linear array of a plurality of mating fingers spaced apart along their respective lengths. The contacts are positioned in the housing such that the first contact is in close proximity to, but spaced apart from the second contact, and the first contact is parallel to the second contact. The mating fingers of the first contact are interdigitated with, but not electrically contacting, the mating fingers of the second contact. An insulating member may be positioned in a space between the first contact and the second contact.

[0006] In a second aspect, this invention provides a method for making an in-line connector, including supplying first and second contacts, each with a plurality of mating fingers spaced along their respective lengths and a plurality of terminals opposed from the fingers. A housing is also provided, wherein the housing has a recess for accepting the contacts and a plurality of openings in a bottom face of the housing for accepting the terminals. The method includes arranging the first and second contacts in the recess such that they are spaced apart but are in close proximity with each other and are substantially parallel to each other, with the fingers of the first contact interdigitated with, but not contacting, the fingers of the second contact. The method includes inserting the terminals into the openings in the housing and positioning a first insulating member between the contacts.

[0007] In a third aspect, this invention provides an in-line connector including a housing, a first linear array of a plurality of first contacts electrically isolated from each other and longitudinally spaced apart from each other along a first length of the housing and positioned in the housing, and a second linear array of a plurality of second contacts electrically isolated from each other and longitudinally spaced apart from each other along the first length of the housing and positioned in the housing. The first and second linear arrays are in close proximity with each but are spaced apart transversely from each other and are essentially parallel with each other. A first insulating member is positioned between the first and second arrays. Each of the contacts includes at least one mating finger. The mating fingers of contacts of the first linear array are interdigitated with, but not in electrical contact with, the mating fingers of contacts of the linear second array. [0008] In a fourth aspect, this invention provides an in-line connector including a housing, a first linear array of a plurality of first contacts electrically isolated from each other and longitudinally spaced apart from each other along a first length of the housing. The first contacts each comprise at least one mating finger. The connector also includes a contiguous contact having a linear array of a plurality of mating fingers spaced apart along its length. The first linear array of first contacts and the contiguous contact are positioned in the housing such that the first linear array of first contacts is in close proximity to and spaced apart from the contiguous contact, and the first linear array is parallel to the contiguous contact. The mating fingers of the first contacts are interdigitated with and not electrically contacting, the mating fingers of the contiguous contact. An insulating member may be positioned in a space between the first linear array of first contacts and the contiguous contact.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The drawings illustrate the design and utility of a preferred embodiment of the present invention, in which similar elements are referred to by common reference numerals. In order to better appreciate the advantages and objects of the present invention, reference should be made to the accompanying drawings that illustrate this preferred embodiment. However, the drawings depict only one embodiment of the invention, and should not be taken as limiting its scope. With this caveat, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

Figure 1 is a perspective view of one embodiment of an interconnect of the present invention;

[0011] Figure 2 is a perspective view of one embodiment of a contact of the present invention;

[0012] Figure 3 is a perspective view of one embodiment of an insert of the present invention;

[0013] Figure 4 is a perspective view of the interconnect of Figure 1 with the insert removed for a better view of the contacts;

[0014] Figure 5 is a perspective section view of the interconnect of Figure 4 taken along line 5-5; [0015] Figure 6 is an enlarged perspective view of the interconnect of Figure 5 with the insert of Figure 3 placed in the interconnect.

DETAILED DESCRIPTION OF THE INVENTION

[0016] Referring to Figure 1 , the present invention provides an interconnect 2 for electrically connecting two printed circuit boards (not shown). The interconnect 2 includes a housing 3. The housing 3 is generally rectangular having two opposed sidewalls 4, 6 parallel to a major axis A and two opposed end walls 8, 10 perpendicular to the axis A. The housing 3 also includes a mounting face 12 for mounting onto a first printed circuit board and a mating face 14 for mating with a second printed circuit board. The housing is made from a dielectric (insulating) material, e.g., a high temperature thermoplastic such as nylon, polyester, polyimide, PEEK or LCP (liquid crystal polymer). The housing 3 also includes a first pair of alignment posts 15 extending from the mating face 14 and a second pair of alignment posts 15 extending from the mounting face 12. In a preferred embodiment, the posts 15 extending from the same face are of different diameters to provide a polarity or keying feature. These posts 15 are received in corresponding openings or recesses in the printed circuit boards. In the illustrated embodiment, the interconnect 2 also includes contacts 16. The contact 16 is illustrated in detail in Figure 2.

[0017] As shown in Figure 2, the contact 16 includes a main body portion 18 which is generally rectangular in shape. A plurality of mating fingers 20 extend from a first edge 27 of the main body 18. The mating fingers can be uniformly spaced along the length of the contact. The mating fingers 20 include a generally straight portion 24 that is integrally formed with the main body 18 and a curved or spring portion 22 that is integrally formed with the straight portion 24. In an alternate embodiment, the straight portion 24 is slightly curved although to a lesser degree then the spring portion 22. The spring portion 22 terminates at an engagement surface 23. When the interconnect 2 is mated to a printed circuit board at the mating face 14, the fingers 20 engage corresponding conductive surface pads formed in an array corresponding to the plurality of fingers present in the interconnect 2. As illustrated in Figure 1, the fingers 20 extend beyond the mating face 14. As such, when the interconnect is mated to the printed circuit board and the engagement surface 23 of the fingers 20 engages the corresponding surface pad on the printed circuit board, the spring portion 22 bends slightly to allow the board to abut the mating face 14, making electrical connections between the surface pads on the PCB and the fingers. The plurality of fingers are all aligned in a fashion such that if one were to view the contact 16 from an end, one would see essentially only the first finger in the line of sight. Furthermore, the fingers 20 have a width X and are separated along the contact 16 by a distance W (measured between the edges of the fingers which are closest to each other), where W is greater than X. This will allow two contacts to be positioned adjacent to each other and offset along their length such that the fingers of one contact can be interdigitated with, but not contacting, the fingers of the other contact, as will be discussed further below.

[0018] A plurality of terminals 26 extend from a second edge 28 of the main body portion 18 of the contact 16, opposed to the first edge 27. In the illustrated embodiment, the terminals 26 are represented as compliant contacts, specifically eye-of-the-needle throughhole posts. In this configuration, the through-hole posts are received in corresponding throughholes or vias in one of the aforementioned printed circuit boards. The vias will typically be coated with a conductive material (e.g., solder such as SnPb, Sn, Cu, Au, or Ag) and connected to conductive traces on the board. Preferably the through-hole posts are sized so that their width is slightly greater than the diameter of the vias so that a friction or press fit between the posts and the vias is achieved, creating a solderless connection. In many cases, it is desired to form such solderless connections to eliminate the requirement that electronics be exposed to high temperature of a soldering step, e.g., a reflow step in which the electronics must travel through an oven hot enough to make solder melt. However, in other cases, it may be desired to subsequently expose the interconnect 2 and board to a soldering process such as a reflow method to more securely fix the posts to the board and vias. As shown in Figure 2, the terminals may be eye-of-the-needle compliant contacts, where the compliant section of the contacts includes a hollow area incorporating small projections towards the center of the hollow area; however any type of compliant contact may be used. Examples of compliant contacts which can be used are disclosed in U.S. Patent No. 5,564,954. The terminals may also be formed in a surface mount configuration for mounting on an array of conductive surface pads that are in turn connected to corresponding circuit traces. The contacts and terminals are preferably made from a spring tempered copper alloy, for example beryllium copper. Copper alloys having high conductivity around 50% IACS (International Annealed Copper Standard) or high are preferred for many applications. The contacts are preferably made of metal which is 0.010" (0.25mm) thick or less, for example 0.009" (0.23mm) or 0.008" (0.20mm) thick. When the interconnect 2 is positioned between the two printed circuit boards and the connecting posts 15 are received in the corresponding holes of the printed circuit board, the two boards are brought together until each board abuts the corresponding face (i.e., one board will abut the mounting face and one board will abut the mating face) and the interconnect 2 is seated against the boards. [0019] Referring to Figure 3, the interconnect 2 also includes an insert 28. The insert 28 operates to hold the contacts 16 in the housing 3, and to generally align the fingers 20 and separate and insulate adjacent fingers from each other. The insert 28 is preferably made of a dielectric (insulating) material, and preferably made of the same dielectric material from which the housing is made. Examples of dielectric materials that can be used are high temperature thermoplastics such as nylon, polyester, polyimide, PEEK and LCP. The insert 28 has a longitudinal axis B that is parallel to the housing axis A when the insert 28 is positioned within the housing 3. The insert 28 includes a mating face 30 and a mounting face 32. The insert 28 also includes end surfaces 34, 36. Along each of the opposing sides of the insert 28 between the end surfaces 34, 36 is an array of slots extending between the mating face 30 and mounting face 32. The slots can be evenly spaced along the length of the insert. The slots preferably alternate between deeper 38 and shallower 40 slots, relative to a direction transverse to the insert axis B. Each slot 38, 40 is separated from an adjacent slot by wall 39. The insert also includes a plurality of mounting, locking extensions 48 which are received in the housing 3, as will be discussed further below. The mounting extensions 48 include a locking feature (not shown), for example a protrusion that extends laterally from each side of the extension.

Figure 4 illustrates the interconnect 2 with a plurality of contacts 16 (specifically four: 16a, 16b, 16c, 16d) mounted in the housing 3 without the insert 28. Figure 4 illustrates adjacent contact pairs 16a, 16b and 16c, 16d as being longitudinally offset and with fingers 20a of a first contact 16a interdigitated with fingers 20b of the adjacent contact 16b. The adjacent contacts are positioned within close proximity to each other. For example, in some cases the spacing between contacts is less than 0.5mm (0.020") and in other cases, less than 0.3mm (0.012").

[0021] Referring to Figure 5, there is illustrated a section view of Figure 4 along section line 5-5. As shown therein, the housing 3 includes a cavity 41 having a generally U-shaped cross section and two longitudinal slots 42 extending between the cavity 41 and the mounting face 12. The slots 42 are each wide enough to receive the main body portion 18 of two contacts 16 and to provide a space 44 therebetween. The housing includes an array of holes 43 between the bottom of each slot 42 and the mounting face 12. The holes of the array of holes 43 are positioned to receive the terminals 26 of two adjacent but transversely separated and longitudinally offset contacts 16. In a preferred embodiment, the interconnect 2 will include a dielectric material (not shown) in the space 44 between the adjacent contacts. This material will provide additional insulation between the adjacent contacts. The dielectric material can either be integral with the housing or be a separate element from the housing. The housing also includes a plurality of mounting slots 45 to receive the mounting extensions 48. As noted above with reference to Figure 2, adjacent fingers of a contact are separated by a space W. As illustrated in Figure 5, the separation between adjacent fingers 16 is great enough to position a finger of an adjacent contact therein and also to provide a space 50 between the interdigitated fingers.

[0022] Figure 6 is the same section view as Figure 5 but enlarged and including the insert 28. As illustrated therein, when the insert 28 is positioned in the U-shaped channel such that the mounting extensions 48 are positioned within the mounting slots 45, the locking feature extends past a shoulder 49 in the slot 45 and the insert 28 is locked in place in the housing 3. As a result, a first pair of contacts 16 on a first side of the housing axis A are positioned such that the fingers 20 of a first contact are positioned within the deeper slots 38 and the fingers 20 of a second, adjacent contact are positioned within the shallower slots 40. Furthermore, adjacent fingers 20 are separated by slot walls 39 that are positioned in the spaces 50 between adjacent fingers 20. As the insert is fully seated in the U-shaped channel, a bottom edge or surface 46 of each wall 39 engages and abuts a top edge of the main body portion 18. This serves to hold the contacts 16 in place within the housing 3. This is also the case for a second pair of contacts 16 on a second side of the housing axis A.

[0023] One application of the present invention is to connect a voltage regulator module (VRM) printed circuit board to other printed circuit boards, to enable board-to-board power distribution. A specific application is to connect a VRM printed circuit board to a microprocessor printed circuit board. From an electrical performance standpoint, it is desired to keep both the resistance and the inductance of the connector in these application as low as possible to minimize voltage drop across the connector. The resistance can be minimized by choosing high conductivity materials and designing the connector to have an electrical path with short path lengths and large cross-sectional areas. Loop inductance is proportional to the magnetic field produced by the power path/return (ground) path of the configuration. Short path lengths will help to minimize loop inductance. Furthermore, magnetic field cancellation is a function of the geometry and separation of the power path and return path. The smaller the gap between power and ground, the more effective the magnetic field cancellation becomes, and the loop inductance of the connector can be minimized. The loop inductance of a connector of the present invention can be 200pH or less, compared to loop inductances of existing connectors such as card edge connectors or blade and socket connectors which are generally 2nH or greater. [0024] It is known in the art to use coaxial interconnects to connect two printed circuit boards, as described in international application WO 01/67512 A3 and U.S. Patent Nos. 6,618,268 and 6,623,279, which are incorporated herein by reference. Referring to Figure 2B of the international application, in the configuration shown, a first or inner conductive member 105 A provides a line or power path from the VRM board to the microprocessor board and a second or outer conductive member 105B provides a return or ground line from the microprocessor board to the VRM board. As such, while the coaxial geometry of this interconnect can provide low inductance, it is not a suitable approach for the efficient utilization of space, e.g., circuit board real estate.

[0025] Board real estate can be used more efficiently with an in-line connector configuration of the present invention. In the present invention, referring to Fig. 4, a first pair of contacts 16a, 16b to a first side of the interconnect 2 (transverse to the housing axis A) includes a first contact 16a that serves as a line or power contact and a second contact 16b that serves as a return or ground contact. The close proximity and interdigitation of the first and second contacts in the interconnect 2, and the resulting small well-controlled distance between the ground and power paths, can lead to very low loop inductance. The interconnect 2 can include two power/return paths, one to each transverse side of the housing axis A.

[0026] In an alternate embodiment, the individual contacts 16 of the present invention may be separated into multiple contacts to provide additional line inlerconnects. More particularly, referring to Figure 2, each contact 16 in a pair of contacts may be divided into two or more contacts by separating the contact al a line on the main body portion 18, for example at one or more of the dashed lines 60. The multiple contacts formed by sub-dividing the contact 16 in a manner illustrated by the dashed lines 118 each must have at least one mating finger. The sub-divided contacts can be arranged in a linear array, where the sub- divided contacts in a linear array are spaced apart longitudinally and electrically isolated from each other. First and second linear arrays of sub-divided contacts may be arranged in the housing 3 of the interconnect 2 in a manner analogous to contiguous first and second contacts 16. That is, the first linear array is placed in close proximity to, but transversely spaced apart from, the second linear array, and the first linear array is essentially parallel to the second linear array. An insulating member may be positioned between the first and second linear arrays. In this manner, two, three, four or more line interconnects may be created. Each contact may include one or more fingers 20, depending upon the application requirements. In addition, the contacts 16 may be scaled either up or down to include more or fewer fingers 20 in an interconnect than are illustrated herein. Furthermore, features from the first embodiment of the interconnect can be combined with features of the alternate embodiment to create other interconnects. For example, an individual contiguous contact 16 may be used in combination with a linear array of multiple contacts, where the contiguous contact 16 is placed in close proximity to but transversely spaced apart from the linear array of multiple contacts, with mating fingers of the contiguous contact 16 interdigitated with mating fingers of the multiple contacts in the linear array. Interconnects of the present invention using linear arrays of multiple contacts can be easily customized, allowing the interconnects to be used in a variety of applications.

[0027] The foregoing detailed description of the invention includes passages which are chiefly or exclusively concerned with particular parts or aspects of the invention. It is to be understood that this is for clarity and convenience, that a particular feature may be relevant in more than just the passage in which it is disclosed, and that the disclosure herein includes all the appropriate combinations of information found in the different passages. Similarly, although the various figures and descriptions thereof relate to specific embodiments of the invention, it is to be understood that where a specific feature is disclosed in the context of a particular figure, such feature can also be used, to the extent appropriate, in the context of another figure, in combination with another feature, or in the invention in general.

[002§] It will be understood that the above-described arrangements of apparatus and the methods therefrom are merely illustrative of applications of the principles or this invention and many other embodiments and modifications may be made without departing from the spirit and scope of the invention as defined in the claims.

Claims

What is claimed is:

1. An in-line connector comprising: a housing; a first contact having a linear array of a plurality of mating fingers spaced apart along a length of the first contact, the first contact positioned in the housing; and a second contact having a linear array of a plurality of mating fingers spaced apart along a length of the second contact, the second contact positioned in the housing such that the second contact is essentially parallel to and spaced apart from the first contact, and the mating fingers of the first contact are interdigitated with and not contacting the mating fingers of the second contact.

2. The connector of claim 1 , comprising a first insulating member positioned in a space between the first contact and the second contact.

3. The connector of claim 1, wherein the connector is positioned between first and second circuit boards such that a mounting face of the housing abuts the first circuit board and a mating face of the housing abuts the second circuit board and one of the contacts provides a power path and the other contact provides a ground path between the boards.

. The connector of claim 1 , comprising a second insulating member having a plurality of slots separated by walls, wherein: the slots are spaced along a first length of the second insulating member; the slots extend from top to bottom surfaces of the second insulating member; one mating finger is positioned within one slot of the second insulating member and a slot wall extends between adjacent fingers; and the second insulating member is positioned within the housing and bottom surfaces of the slot walls are positioned on top edges of the contacts.

5. The connector of claim 4, wherein the slots alternate in depth between a first depth and a second depth, and wherein the fingers of one of the contacts are only positioned in slots of the first depth and the fingers of the other contact are only positioned in slots of the second depth.

6. The connector of claim 4, wherein the second insulating member comprises a mounting tab extending from a bottom surface of the second insulating member and the housing comprises an opening to accept the mounting tab.

7. The connector of claim 1 , wherein the first contact is spaced apart from the second contact by less than 0.5mm.

8. The connector of claim 1 , wherein the contacts have a thickness of less than or equal to 0.25mm.

9. The connector of claim 1, wherein the contacts comprise a spring metal.

10. The connector of claim 9, wherein the spring metal comprises beryllium copper.

11. The connector as in claim 10, wherein the beryllium copper has a conductivity of equal to or greater than 50% relative to a conductivity of copper.

12. The connector of claim 1, wherein the mating fingers have a flat portion and a curved portion, wherein the flat portion is positioned within the housing and the curved portion extends beyond a mating face of the housing.

13. The connector of claim 12, wherein the curved portion of the mating fingers makes electrical contact with conductive pads on a printed circuit board.

14. The connector of claim 1 , wherein the contacts comprise terminals extending opposite the fingers, and the housing comprises openings in a mounting face through which the terminals extend.

15. The connector of claim 2, comprising: a third contact having a linear array of a plurality of mating fingers spaced apart along a length of the third contact, the third contact positioned within the housing; a fourth contact having a linear array of a plurality of mating fingers spaced apart along a length of the fourth contact, the fourth contact positioned within the housing such that the fourth contact is parallel to and spaced apart from the third contact, and the mating fingers of the third contact are interdigitated with and not contacting the mating fingers of the fourth contact; and a third insulating member positioned in a space between the third contact and the fourth contact.

16. The connector of claim 15, comprising: a second insulating member having a plurality of slots separated by walls, wherein: the slots are spaced along first and second lengths of the second insulating member, the first length being opposite the second length; and the slots extend from top to bottom surfaces of the second insulating member; wherein: the first and second contacts are positioned in the housing along a first length of the housing and the third and fourth contacts are positioned in the housing along a second length of the housing; one mating finger is positioned within one slot of the second insulating member and a slot wall extends between adjacent fingers; the fingers of the first and second contacts are positioned only in slots along the first length of the second insulating member; the fingers the third and fourth contacts are positioned only in slots positioned along the second length of the second insulating member; and the second insulating member is positioned within the housing and bottom surfaces of the slot walls are positioned on lop edges of the contacts.

17. The connector of claim 16, wherein the slots along the first length of the second insulating member alternate in depth between a first depth and a second depth, and the fingers of one of the first and second contacts are positioned only in slots of the first depth and the fingers of the other of the first and second contacts are positioned only in slots of the second depth, and the slots along the second length of the second insulating member alternate in depth between a first depth and a second depth, and the fingers of one of the third and fourth contacts are positioned only in slots of the first depth and the fingers of the other of the third and fourth contacts are positioned only in slots of the second depth.

18. The connector of claim 16, wherein: one of the first and second contacts supplies a first power path and the other of the first and second contacts provides a ground path between a first printed circuit board and a second printed circuit board; and one of the third and fourth contacts supplies a second power path and the other of the third and fourth contacts provides a ground path between the first printed circuit board and the second printed circuit board.

19. A method for making an in-line connector, comprising: providing first and second contacts, wherein: the first contact has a plurality of mating fingers spaced along a length thereof and a plurality of terminals extending opposed from the fingers; the second contact comprises a plurality of mating fingers spaced along a length thereof and a plurality of terminals extending opposed from the fingers; providing a housing comprising a recess for accepting the contacts and a plurality of openings in a bottom surface of the housing; and arranging the first and second contacts to be spaced apart and in close proximity with each other and substantially parallel to each other in the recess, such that the mating fingers of the first contact are interdigitated with and not contacting the mating fingers of the second contact and such that the terminals of the contacts are inserted into the openings.

20. The method of claim 19 comprising providing a first insulating member positioned between the contacts and within the recess.

21. The method of claim 19, comprisin : providing a second insulating member having a plurality of slots having walls, the slots being spaced along a length of the second insulating member, wherein the slots extend between top and bottom surfaces of the second insulating member; and positioning the second insulating member within the housing such that one mating finger is positioned in one slot of the second insulating member, and a slot wall extends between adjacent fingers.

22. The method of claim 21 , wherein the slots alternate in depth between a first depth and a second depth, and wherein the fingers of one of the contacts are positioned only in slots of the first depth and the fingers of the other contacts are positioned only in slots of the second depth.

23. An in-line connector comprising: a housing; a first linear array of a plurality of first contacts, the first contacts being spaced apart longitudinally from each other along a length of the housing, electrically isolated from each other, and positioned in the housing; and a second linear array of a plurality of second contacts, the second contacts being spaced apart longitudinally from each other along a length of the housing, electrically isolated from each other, and positioned in the housing such that the second linear array is in close proximity to and spaced apart transversely from the first linear array and is essentially parallel to the first array; wherein: each contact comprises at least one mating finger; and the mating fingers of the first contacts of the first linear array are interdigitated with and not contacting the mating fingers of the second contacts of the second linear array.

24. The connector of claim 23, comprising a first insulating member positioned between the first array and the second array.

25. The connector of claim 23, wherein each mating finger has a flat portion and a curved portion, wherein the flat portion is positioned within the housing and the curved portion extends beyond a mating face of the housing.

26. The connector of claim 23, comprising a second insulating member having a plurality of slots separated by walls, wherein: the slots are spaced along a first length of the second insulating member; the slots extend from top to bottom surfaces of the second insulating member; one mating finger is positioned within one slot of the second insulating member and a wall extends between adjacent fingers; and the second insulating member is positioned within the housing.

27. The connector of claim 26, wherein the slots alternate in depth between a first depth and a second depth, and wherein the mating fingers of contacts of one of the linear arrays are only positioned in slots of the first depth and the mating fingers of contacts of the other linear array are only positioned in slots of the second depth.

28. The connector of claim 27, wherein the second insulating member is positioned within the housing such that bottom surfaces of the slot walls are positioned on top edges of the contacts.

29. The connector of claim 23, wherein each of the plurality of first contacts provides a separate power path between two circuit boards and each of the plurality of second contacts provides a ground path between the circuit boards.

30. An in-line connector comprising: a housing; a first linear array of a plurality of first contacts, wherein the first contacts are spaced apart longitudinally from each other along a length of the housing, electrically isolated from each other, and positioned in the housing; and a contiguous contact positioned in the housing comprising a second linear array of a plurality of mating fingers; and wherein: the contiguous contact is in close proximity to and spaced apart from the first linear array of first contacts and is essentially parallel to the first linear array; each contact of the first linear array comprises at least one mating finger; and the mating fingers of the first contacts of the first linear array are interdigitated with and not contacting the mating fingers of the contiguous contact.

31. The connector of claim 30, wherein an insulating member is positioned between the first linear array of a plurality of first contacts and the contiguous contact.