Microwave Journal

High Density RF Interconnect

October 19, 2007

With system space ever at a premium and operating frequencies constantly on the rise today’s RF/microwave interconnection cables must follow suit and be smaller and higher performance. One of the limiting factors to this progression has always been the cable connector. Its pin/socket-type male and female interconnect system adds much real estate and mechanical complexity.

The HDRFI™ is a Tensolite patented high frequency connection system that transfers high frequency signals through a unique planar interface. This planar interface removes the need for typical pin and socket connections by utilizing a z-axis elastomer to provide the electrical path between the mated connectors. The elastomer is made up of silicone, impregnated with gold-plated stainless steel wires and is arranged on a 0.035 mm pitch. When compressed by the mating halves, the gold-plated wires mechanically connect the two planar surfaces and create an electrical EMI barrier to provide excellent isolation.

The result is a high density, high bandwidth, compact RF interconnect with a center-to-center spacing of 0.130" where the alignment of the connector is independent of the RF path. The new interconnect system eliminates stubbing and can be used differentially or single ended. Figure 1 shows typical RF performance of an HDRFI assembly to 40 GHz.

HDRFI is available only as an assembly in three product lines: RF D-Sub, RF Circular, Mixed Signal and in custom applications. The assemblies can be used with a 26AWG coax for internal applications or 24AWG for external requirements.

The RF D-Sub connector family is available in four different shell sizes and can be used in cable-to-cable, cable-to-board or board-to-board applications. The insert arrangements are designed to hold multiple impedance-controlled size 16 type RF press-in style contacts and the connectors can accommodate standard D-Sub backshells and mounting hardware. Figure 2 shows an HDRFI RF D-Sub connector and its mating face.

The RF Circular connector family is designed for high performance applications. The insert arrangements have been designed to maximize the number of size 16 RF contacts available in a standard circular connector arrangement. The product line consists of shell sizes 15 to 25 and is based on the D38999 Series III specification.

The HDRFI RF contacts are press-in style and the connectors can accommodate standard D38999 back-shells and hardware. Fully loaded the RF Circular connector system contains up to 34 40 GHz RF contacts. Figure 3 shows an HDRFI RF Circular connector face.

The RF Circular-Mixed Signal connector family combines both power and high frequency RF contacts in the same connector body. The product line consists of shell sizes 15 to 25 and is based on the D38999 specification as well. The power pins are size 20, rated to 7 A, and are combined with HDRFI RF contacts.

Figure 4 shows an HDRFI RF Circular-Mixed Signal connector. HDRFI can be customized to fit almost any application, from custom board connectors to insert arrangements that can have a common groundplane, to having each signal path isolated from each other.

The RF Circular products are ideal when upgrading legacy systems that use typical D38999 type connectors for increased performance or to reduce the amount of connections in a box by combining RF and power signals into the same circular connector. Other custom designs may include the direct attachment of the HDRFI contact to the planar array.

Tensolite, a Carlisle company,
St. Augustine, FL
(904) 829-5600
(800) 458-9960

RS No. 301