CA1306024C - Electrical circuit interconnection - Google Patents

Abstract

412-1707 A high frequency electrical connector system for electrically interconnecting corresponding first and second circuit elements includes a first planar array of pad-type contact terminals disposed on a substrate and connected to a first circuit on the substrate, together with first guide structure adjacent the first array of contact terminals. A cooperating second array of pad-type contact terminals is mounted on a rigid nonconductive contact support structure that includes a resilient contact terminal array mounting, camming structure and second guide structure for cooperation with the first guide structure. The contact support structure is resiliently coupled to a carrier structure that includes cooperating camming structure. Flexible multi-conductor interconnection structure has one end electrically connected to a cooperating electrical circuit secured to the carrier structure and its other end connected to corresponding terminals of the second array. Fastener structure is adapted to secure the carrier structure and the substrate together with guide structures in engagement. As the fastener structure moves the carrier structure towards the substrate, the camming structures interact and move the contact support structure laterelly (parallel to the plane of the contact arrays) in transverse wiping action, as directionally guided by the engaged first and second guide structures, to remove debris or other foreign matter (such as corrosive films) which may adversely affect electrical circuit performance.

Description

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- -- B~ackqround of the Invention This invention relates to electrical circuit interconnections, and more particularly to connector arrangements of the type useful with electronic circuit components of the semiconductor type.
Integrated circuitry developments require circuit interconnection configurations of greater density, as well as circuit path configurations that control impedance and resistive effQcts which may alter circuit performance. Conventionally employed methods of interconnecting electrical or electronic circuit components have included the "pin-and~socket" type and the so-called "zero force insertion" type in which a circuit card may be inserted when cooperating contacts are in an open position, and the contacts are then cammed to a closed position. These and other techniques have reguired substantial space or generally have a tendency to utilize complex arrangements and complicated manufacturing procedures. Additionally, certain types of commercially employed connectors cannot be easily matched in impedance to the circuit cards being connected, thus causing reflections which degrade signal quality. Such problems are particularly acute when connectors are used with newer generation semiconductors which have high switching speeds (100 - 500 picosecond~
rise time), low switching enQrgy and signal swings in the microvolts range, the resulting disadvantages including poor signal ~uality caused by high crosstalk, rise time degradation, and refiections due to impedance mismatch.

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Sumn~ary of the nvention In accordance with one aspect of the invention, there is provided a high fre~lency electrical connector system for electrically interconnecting a first circuit element with a second circuit element. The system includes a first planar array of pad-type contact terminals that are disposed OIl a nonconductive substrate and connected to a first circuit on the substra~e, together with first guide structure adjacent the first contact terminal array. A cooperating second array of pad-type contact terminals is mounted on a rigid nonconductive contact support structura that includes camming structure, a resilient contact array mounting, and second guide structure for cooperation with the first guide structure. The contact support structure is resiliently coupled to a carrier structure that includes cooperating camming structure opposed to the camming structure of the contact support structure. Flexible multi-conductor interconnection structure has one end of 2Q the conductors electrically connected to a cooperating electrical circuit secured to the carrier structure and the other end of the cond~lctors connected to corresponding pad-type contact terminals of the second array. Fastener structure is adapted to secure the carrier structura and the substrate together with the first and second guide structures in engagement. With the arrays of planar pad-type contact terminals in face-to-facQ engagement, as the fastener structure moves the carrier structure towards the substrate, the camming structures interact and move the contact support structure laterally (parallel to the plane of the contact arrays) in transverse wiping action as directional].y quided by the engaged first and second guide struct:ures to remove debris or other foreign ~L3~6~2~

matter (such as corrosive ilms) which may adversely affect electrical circuit performance.
In preferred embodiments, the flexible interconnection structure includes a plurality of conductor traces and a ground plane, and each conductor trace has the same characteristic impedence as other conductor traces, the clamping and wiping interactions providing circuit interconnections of minimal resistance and impedance reflectio~. In ,a particular embodiment, the pad-type contacts at one end of the flexible interconnection structure have spacing different from tha spacing on center of the terminals at the other end.
Also in preferred embodiments, the second array of pad-type contacts lies in a plane and the camming structures of the carrier and contact support structures are planar surfaces that are disposed at an acute angle to the plane of the array of pad-type contacts; and the first guide structure includes an upstanding post member that is received in a guide slot between ~wo spaced projecting members of the contact support when the pad-type contact arrays are in face-to-face engagement.
In a particular module-to-board connector embodiment, the carrier structure supports a module with a plurality of chip carriers and includes four planar ramp surfaces disposed in rectangular arrangement, and a corresponding contact support structure is mountad on each ramp surface. Each ramp surface has an elongated slot therein and thQ resilient coupling between the support structure and the carrier structure includes a post structure that extends through the ramp slot and is engaged by a spring member that biases the camming structures of the support and carrier structures into engagement wi.th one another. The resilient contact ~3~ Z~

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array mountinq includes a foam elastomer strip that ?referably has low stress relaxation when compressed five to fifty percent of its thickness and provides conormability and controlled contact force.
In accordance with another aspect of the invention, there is provided an electrical connectox arrangement of the solderless type in which first and second planar ~rrays of pad-ty~e contact terminals are adapted for face to face enqagement. Means are provided for ~.oving one of the arrays of contact terminals rslative to the other contact terminal array in contact wiping action for cemoving surface contamination.
In accordance with anothec aspect of the invention, there is provided an electrical connector assembly for connecting a first array of electrical contacc terminals supported on a rigid member having a generally planar face witn a corresponding second array of electrical contact terminals carried by a flexible circuit. The connector assembly includes a support structure having a face opposed to the planar face of the rigid member and mounted to press the flexible circuit mounted array of contact terminals toward the rigid member and move that array laterally, parallel to the face o the rigid member to pro~ide wiping between the engaged arrays of contact terminals. The connector assembly further includes ca~ming means supported for actuating movement in the direction perpendicular to the face of the rigid member, and movable to produce lateral mo~ion of the support structure in response to perpendicular actuating motion of the camming means.
In particular embodiments, the support structure is of a form generally correspondinq to the outline of the first array, and the camming means is of ~3~

generally corresponding form and lies predominantly within lines projected perpendicular to the face of the rigid member board from the outline of the contact terminal array on that face, whereby wiping engagement of a series of close-together contacts can be achieved by means which covers little excess area of the array of contacts on the'rigid circuit board. In a particular embodiment, the connector assembly includes four contact array sets, and the support structure and camming means are assembled upon a single rigid member in a hollow square pattern, and a chip carrier module is disposed on the single rigid member within the sguare pattern. The flexible cirsuits comprise controlled characteristic impedance strip means. The contacts in the arrays are lS spaced apart and provide connections with high contac~
density and controlled impedance.
In accordance with another aspect of the invention, there is provided electrical connector structure of the solderless type for providing electrical connections to a first array of pad-type contact terminals on a substrate or the like. The connector structure includes contact support structure that carries a corresponding array of resiliently mounted pad-type contact terminals and has a camming surface. The contact support structure is resiliently coupled to a carrier structure that includes camming structure that engages the contact support structure camming surface. Extending from the fixed array of pad-type contact terminals of the array carried by the contact support structure is flexible multi-conductor interconnection structure that has electrical terminals at its other end connected to circuits on the carrier structure. With the pad-type contact terminal array in face-to-face engagement, movement of the carrier ~L3~6~2~

structure toward the first planar array causes the camming surface structure to produce lateral movemen~ of the contact support structure and wiping action of the enga~ed pad-type contact terminal arrays, providing low resistance circuit interconnections.
In a particular embodiment, one or more chip carriers are on a module that :is mounted on the carrier structure and terminals of the module are fixed to conductor traces of a flexible shee~-form interconnection structure that includes a ground plane impedance control trace and a low loss, low dielectric constant member, each conductor trace having a characteristic impedence matched to the impedance of the integrated circuit. A pad-type contact terminal is at the other end of each conductor trace, those pad-type contact terminalc being spaced and disposed in a planar array that is secured to a carrier bar.

The connector assembly provides a controlled impedance connection with low crosstalk and high propagation velocity in an environmentally reliable, high density interconnection which is electrically invisible even at very high frequencies.
Other features and advantages of the invention will be seen as the following description of a particular embodiment progresses, in conjunction with the drawings.
Preferred Embodiments We first briefly describe the drawings.
Fig. 1 is a plan view of a printed circuit board with a rectangular array of terminals;
Fig. 2 is a perspective view of a module-to-board connector assembly in accordance with ~3~

the invention for cooperation with the printed circuit board of Fig. 1, showing a chip carrier module and contact array;
Fig. 3 is an exploded perspective view of components of the chip carrier module and contact array of Fig. 2, showing a terminal support assembly;
Fig. 4 is a plan view of the carrier frame member of Fig. 3;
Fig. 5 is a side view of the frame member of Fig. 4;
Fig. 6 is a sectional view taken along the line 6-6 of Fig. 4;
Fig. 7 is a plan view of a contact support bar of the terminal support assembly of Fig. 3;
Fig. 8 is a front view of the support bar of Fig. 7;
Fig. 9 is a sectional view taken along the line 9-9 of Fig, 7;
Figs. lOA and lOB are plan views of flexible signal conductor arrays employed in a particular embodiment of the invention;
Fig. lOC is an enlarged diagrammatic view of the superimposed contact arrays;
Fig. lOD is a p}an view of the contact arrays shown in Fig. lOC; and Figs. ll and 12 are sectional diagrammatic views illustrating the wiping and electrical connection actions of the connector assembly of Fig. 2.
Description of Particular_Embodiment Figure 1 is a diaqrammatic view of a circuit board lO having a substrate ll on which is disposed one or more printed circuits, represented by area 12, with an associated rectangular "footprint" in the form bf two rows of pad-type contact terminals in a terminal array ~L306~Z~

14 (signal terminals 14A and ground terminals 148). As is known, terminals 14 are connected to circuit(s) 12 (which may be located inside o:r outside "footprint" 14 (or both)) via plated-through holes to connector traces on the reverse side of the substrate. At each corner of the array of terminals is a fastener-receiving aperture 16 and two upstanding guide posts 18. Substrate 11 may be of suitable insulating material such as polyimide glass or epoxy glass, and an appropriate stiffening plate 2Q may be secured on the rear side of the substrate 11 in alignment with terminal array 14 and alignment posts 18.
Cooperatiny with printed circuit substrate 11 and terminal array 1~ (as shown in Fig. 2) is connector assembly 30 that includes module 32 on which circuit elements (such as one or more chips or chip carriers, not shown) are mounted and that has a rectangular array of corresponding terminals (not shown) to which are soldered flexible plural conductor (preferably microstrip or strip line3 fifty ohm characteristic impedance transmission line circuits 36 that fan out to the contact density of the circuit board 10. Each flexible circuit 36 has one or more rows of contact pad-type terminals in terminal array 40 at its other ends of the same size and spacinq as terminal array 14.
The four terminal arrays 40 are secured on corresponding carrier bars 42 that are in turn resiliently secured to carrier frame 44 by post structures 46 and spring members 48.
Connector assembly 30 is shown in exploded view in Fig. 3, and further details of carrier frame 44 may be seen with reference to Figs. 4-6. Carrier frame 44 includes a transverse plate 52 with corner post structures 54 on one side on which module 32 is ~3(~6~

secured. Upstanding from the other side o plate 52 is a camming structure of rectan~ular configuration that includes a set of four planar ramp surfaces 56, each of which is disposed at an angle of 50 to the plana of plate 52. Centrally located in and extending perpendicularly through each ramp surface 56 is an elongated slot 58. At each corner of the ramp structure 56 is a fastener aperture 60. A clearance recess 62 is formed in base plate 52 in general alignment with slot 58, and a spring tip capturing recess 64 is ormed in plate 52 on either side of each clearance recess 62.
Each carrier bar 42, as may be seen with reference to Figs. 3 and 7-9, has a planar base surface 70 in which recess 72 is formed and receives resilent, open-cell polyurethane foam pad 74 (which may be of the type described in U.S. Patent 4,468,074) such that the outer surface of pad 74 projects about one millimeter beyond surface 70 of carrier bar 42. At each end of recess 72 is a threaded fastener recess 76 that cooperates with associated fastener portions 116 of flexible transmission line circuits 36. The end surfaces 80 of bars 42 are disposed at 45 angles to the length of the bar so that the surfaces are aligned with one another in the~assembly as shown in Fig. 2, and a recess 8~ ~and corresponding recess 120 (Figs. lOA, lOB)) is formed in each surface for clamp fastener 88.
Extending laterally from surface 70 at either end thereof are a pair of projections 84 that define a guide slot 86 that receives and cooperates with a corresponding guide post 18 on substrate 11. Each carrier bar 42 also include a ramp surface 90 that is ~3~6~3Z~

disposed at an angle of 60 to surface 70, and in which is formed a threaded recess 92 for receiving post structure 46.
Carrier bars 42 are assembled to carrier frame 44 with coupling post structures 46 and spring members 48 such that their ramp surfac~es 90 sea~ on frame ramp surfaces 56. Coupling post st:ructures 46 extend through slots 5~ and are threadedly secured in recesses 92, the central portion of each stainless steel spring ~8 is captured on the head of its post 46 and its end portions are seated in frame recesses 64, as indicated in Fig. 2, so that springs 48 bias the ramp surfaces 90 of carrier bars 42 against and along frame ramp surfaces 56 away from plate 52. The pad-type contact terminal arrays 40 of flexible transmission line circuits 3S are secured to carrier bars 42 by threaded fasteners 98 in threaded fastener recesses 76.
In this connector embodiment, two superimposed flexible transmission line circuits 36 (Figs. ll, 12) are secured to each carrier bar 42, and provide a transition in terminal density between chip carrier module 32 and pad-type contact terminal arrays 40.
Details o those flexible transmission line circuits 36 may be seen with reference to Figs. lOA - D. Each flexible circuit 36A, 36B is of "microstrip"
configuration and includes one ounce copper ground plane 100 that terminates in exposed ground terminal strips 102, 104 at opposite ends of the circuit (the ground terminal strips 104 corresponding to contact pads 40A of Fig. lOD), three mil thick glass reinforced fluorocarbon (Rogers R~-2500~ dielectric 106 that has a low dielectric constant t2-5) and a low loss factor, a set of one ounce copper conductive circuit traces 108A, 108B

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that extend between terminals pads 110 and terminals pads 112 and cover film, the flexible cîrcuits providing controlled impedence high density transmission line conductors (traces 108) between terminal strip 102 and terminal pad 110 that are soldered to chip carrier module 32 and terminal strip 104 and terminal pads 112 (the signal pads 112 corresponding to contact pads 4oa of Fig. lOD). At either end of the contact pad terminal array 40 is a fastener portion 116 that includes an aperture 118 through which a threaded fastener 98 (Fig.

2) extends into its corresponding threaded fastener hole 76 (the fastener portions 116 being spaced about 2.5 centimeters apart).
The conductive circuit traces 108 are one ounce (1.4 mil) copper and pads 112 are copper plated to about two ounces (about 3 mils).
Referring, e.g., to Fig. 11 in conjunction with Fig. 1, the outlines of the arrays of contacts 14 on the circuit board 10 (and the corresponding arrays 40 on the 1axible circuits 36) are of elongated orm. The carrier bars 42 are of corresponding form. The camming structure that lies directly above each bar 42 is also of generally corresponding form (see, e.g., Fig. 3), lying predominantly within projection lines Pl and P2 (Fig. 11), projected perpendicular to the face of the circuit board 10 from the outline of the carrier bar 42. Areas covered by the actuating mechanisms, i.e., camming ramp surfaces 56, 90, posts 46, etc., are substantially the same as those covered by the mating contact arrays, i.e., 14, 40, leaving adjoining areas of the circuit board available, e.g., for the mounting of components. For instance, in the square of terminal array 14 shown, e.g., in Fig. 1, a component, e.g., an ~30~;a~4 active elect.rical component or a cooling device, can be mounted on the same side of the board as the contacts, and other electrical components mounted outside of the square of the terminal array on the same side of the board as the contacts.
Interaction of the contact assembly 28 (Fig. 2) with the substrate 11 is indicated diagrammatically in Figs. 11 and 12. Contact assemoly 28 is disposed on circuit board 10 as indicated in Fig. 12, with contact pad array 40 seated on but inwardly offset from cooperating substrate pad array 14. As fasteners 88 are tightened to urgQ contact assembly 28 toward substrate 11, (in the direction of arrow 130), the ramp surfaces 56 of frame 44 slide along ramp surfaces 90 of carrier bars 42 against the biasing forces of springs 48 and producing a transverse outward (sliding) movement (in the direction of arrow 132) and wiping action of terminal pads 112 of contact pad array 40 across substrate contact pad array 14. That wiping action removes debris and surface contamination and, together with resilient actions of springs 48 and pads 74, produces durable, electrically invisible, low contact resistance circuit interconnections with clamping forces of about thirty psi.
The disclosed connector assembly provides multiple electrical connections in an arrangement resistant to mechanical and thermal shock which is relatively inexpensive to manufacture, simple to utilize, readily replaceable without the use of solder, 30 and provides reliab~le circuit interconnections with distributed mating forces and wiping actions of pad-type contacts. While particular embodiments have been shown and described, various modifications will be apparent to ;

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those skilled in the art, and therefore it is not intended that the invention be limited to the disclosed embodiments or to details thereof, and departures may be made therefrom within the spirit and scope of the invention.

Claims (32)

1. An electrical connector system electrically interconnecting a first circuit with a second circuit comprising A. a substrate on which said first circuit is disposed, a first array of pad-type contact terminals on said substrate electrically connected to said first circuit, and first guide structure on said substrate adjacent said first array of contact terminals, B. contact support structure having a second array of pad-type contact terminals mounted on said contact support structure by means of a resilient contact array mounting, said contact support structure including camming structure and a second guide structure adapted for cooperation with said first guide structure, C. carrier structure that includes camming structure opposed to said camming structure of said contact support structure, means coupling said contact support structure to said carrier structure in a manner enabling said opposed camming structures to engage, D. multi-conductor flexible interconnection structure that has one end of its conductors electrically connected to respective terminals of said second circuit and the other end of said conductors connected to corresponding pad-type contact terminals of said second array, and E. fastener structure operable, with said first and second arrays of pad-type contact terminals in face-to-face engagement and the first and second guide structures in engagement, to move said carrier structure toward said substrate, said movement toward said substrate causing said engaged camming structures to produce lateral movement of said contact support structure parallel to the plane of the contact terminal arrays in wiping action as guided by said engaged first and second guide structures.

2. The connector system of claim 1 wherein said flexible interconnecting structure includes a plurality of conductor traces and at least one ground plane, each of said plurality of conductor traces having the same characteristic impedance and each being impedance matched to the circuits being interconnected.

3. The connector system of claim 1 wherein said circuits are of the semiconductor type.

4. The connector system of claim 1 wherein said second array of pad-type contact terminals lies in a plane and said camming structure of said contact support structure is a planar surface disposed at an acute angle to said plane of said second array.

5. The connector system of claim 1 wherein said first guide structure includes an upstanding post member, and said second guide structure includes two spaced projecting members that define a guide slot therebetween receiving said upstanding guide post member.

6. The connector system of claim 1 wherein said camming structure of said carrier structure is a planar ramp surface.

7. The connector system of claim 1 wherein said fastener structure between said support structure and said carrier structure includes means for resiliently biasing said camming structures of said support and carrier structures into engagement.

8. The connector system of claim 7 wherein said fastener structure is disposed midway between the ends of said support structure.

9. The connector system of claim 1 wherein a plurality of carrier structures, each including a planar ramp surface, is disposed in a polygon arrangement, and a cooperating support structure is mounted on each said ramp surface.

10. The connector system of claim 1 wherein said resilient contact array mounting includes a resilient sheet member.

11. The connector system of claim 1 wherein said flexible interconnection structure has a plurality of conductor traces with spacing of terminals at one end different from the spacing of the terminals at the other end.

12. An electrical connector system for electrically interconnecting a first array of pad-type contact terminals of a first circuit with a second circuit comprising contact support structure having a second array of pad-type contact terminals mounted on said contract support structure by means of a resilient contact array mounting, said contact support structure including camming structure, carrier structure that includes camming structure opposed to said camming structure of said contact support structure, means coupling said contact support structure to said carrier structure in a manner enabling said opposed camming structures to engage, multi-conductor flexible interconnection structure that has one end of its conductors electrically connected to respective terminals of said second circuit and the other end of said conductors connected to corresponding pad-type contact terminals of said second array, and with said first and second pad-type contact terminals in face-to-face engagement, said carrier structure adapted for movement to cause said engaged camming structures to produce lateral movement of said contact support structure parallel to the plane of the contact terminal arrays in wiping action.

13. The connector structure of claim 12 wherein said flexible multi-conductor interconnection structure includes a plurality of conductor traces and at least one ground plane, each of said plurality of conductor traces having the same characteristic impedence and each being impedance matched to the circuits being interconnected.

14. The connector structure of claim 13 wherein said circuit elements are of the semiconductor type.

15. The connector structure of claim 14 wherein said second array of pad-type contact terminals lies in a plane and said contact support camming structure is a planar surface disposed at an acute angle to said plane of said second planar array of pad-type contact terminals.

16. The connector structure of claim 12 wherein a plurality of carrier structures, each including a planar ramp surface, is disposed in a polygon arrangement, and a cooperating support structure is mounted on each said ramp surface.

17. The connector structure of claim 16 wherein said resilient contact array mounting includes a resilient sheet member.

18. The connector structure of claim 17 wherein said flexible multi-conductor interconnection structure has a plurality of conductor traces with spacing of the terminals at one end different from the spacing of said pad-type contact terminals at the other end,

19. A high frequency electrical connector system for electrically interconnecting a first circuit element with a second circuit element comprising a substrate on which said first circuit element is disposed, a first planar array of pad-type contact terminals on said substrate connected to said first circuit element, and first guide structure adjacent said first array of contact terminals, rigid nonconductive contact support structure that includes camming structure and a second guide structure adapted for cooperation with said first guide structure, a cooperating second planar array of pad-type contact terminals mounted on said rigid contact support structure by means of resilient contact array mounting, rigid nonconductive carrier structure that includes camming structure opposed to said camming structure of said contact support structure, means resiliently coupling said support structure to said carrier structure with said camming structures in engagement, and means for securing said second circuit element to said carrier structure, multi-conductor flexible interconnection structure that has one end of the conductors electrically connected to respective terminals of said second circuit element and the other end of the conductors connected to corresponding pad-type contact terminals of said second array, and fastener structure operable, with said first and second pad-type contact terminal arrays in face-to-face engagement and the first and second guide structures in engagement, to move said carrier structure towards said substrate, said movement towards said substrate causing said engaged camming structures to produce lateral movement of said contact support structure, parallel to the plane of the contact arrays, in wiping action as guided by said engaged first and second guide structures.

20. The connector system of claim 19 wherein said flexible interconnection structure includes a plurality of conductor traces and at least one ground plane impedance control trace, each of said plurality of conductor traces having the same characteristic impedence and each being impedance matched to the circuits being interconnected.

21. The connector system of claim 20 wherein said second array of pad-type contacts lies in a plane and said camming structure of said contact support is a planar surface disposed at an acute angle to said plane of said second array,

22. The connector system of claim 21 wherein said first guide structure includes an upstanding post member, and said second guide structure includes two spaced projecting members that define a guide slot therebetween receiving said upstanding guide post.

23. The connector system of claim 19 wherein said substrate is a circuit board on which said first circuit element is disposed, said second circuit element is a chip carrier disposed on a module secured to said carrier structure.

24. The connector system of claim 23 wherein said carrier structure is of rectangular configuration and has four camming surface structures disposed about its periphery, and four contact support structures are disposed about the periphery of said rectangular carrier structure and are resiliently biased against corresponding camming surfaces of said carrier structure by fastener structures.

25. The connector system of claim 24 wherein said flexible interconnection structure includes a plurality of conductor traces and at least one ground plane impedance control trace, each of said plurality of conductor traces having the same characteristic impedance and each being impedance matched to the circuits being interconnected.

26. In an electrical connector assembly for connecting electrical contact terminals supported on a rigid member with corresponding electrical contact terminals carried by a flexible circuit, the connector assembly being of the type comprising a rigid member having a generally planar face supporting a first array of electrical contact terminals, flexible circuit means having a broad surface upon which is disposed a corresponding second array of electrical contact terminals, a support structure having a face opposed to said planar face of said rigid member, the portion of said flexible circuit means having said second array of contact terminals being supported by said support structure face, with said second array of contact terminals exposed for engagement with said first array of contact terminals, said support structure being mounted to press toward said rigid member and move laterally parallel to said face of said rigid member to provide wiping action between said arrays of contact terminals as they engage, and camming means having a camming surface engaged upon a corresponding surface of said support structure and movable to produce said lateral motion of said support structure while said arrays of contact terminals engage, the improvement wherein said camming means is supported for actuating movement in the direction perpendicular to the face of said rigid member, and said support structure and camming means have mating camming structure arranged to produce said lateral motion of said support structure in response to said perpendicular actuating motion of said camming means.

27. The connector assembly of claim 26 wherein said rigid member comprises a circuit board, said support structure is of a form generally corresponding to the outline of said second array, and said camming means is of generally corresponding form and lies predominantly within projection lines projected perpendicular to the face of said rigid circuit board from the outline of said support structure, whereby wiping engagement of a series of close-together contact terminals can be achieved by means which covers little excess area of the first array of contact terminals on said rigid circuit board.

28. The connector assembly of claim 26 or 27 wherein said flexible circuit means comprises controlled characteristic impedance strip means and contact terminals in said arrays are spaced apart to achieve connections with high contact density and controlled impedance.

29. The connector assembly of claim 27 wherein said flexible circuit means carrying said second array of contact terminals comprises a multiplicity of flexible circuit strips, each carrying a sub-array of contact terminals, said sub-arrays together defining said second array.

30. The connector assembly of claim 27 or 29 wherein the outlines of said first and second array of contact terminals are of corresponding narrow elongated form, and said support structure and camming means are of corresponding elongated, bar form.

31. The connector assembly of claim 27 or 29 wherein the outlines of said first and second array of contact terminals are of corresponding narrow elongated form, and said support structure and camming means are of corresponding elongated, bar form, and wherein four sets of said arrays of contact terminals, support structure and camming means are assembled upon a single rigid member in a hollow rectangular or square pattern.

32. The connector assembly of claim 27 or 29 wherein the outlines of said first and second array of contact terminals are of corresponding narrow elongated form, and said support structure and camming means are of correspondlng elongated, bar form, and wherein four sets of said arrays of contact terminals, support structure and camming means are assembled upon a single rigid member in a hollow rectangular or square pattern, and wherein a module is disposed upon said single rigid member within said rectangular or square pattern.