Hyperboloid Wire Basket Connector Technology Provides High-Performance Interconnect Solutions

Hypertronics Corporation, Hudson, Massachusetts

As high-end electronics become more and more pervasive, reliability and the need to minimize failure are top priorities for many manufacturers. Traditionally, reliability has been a key issue for military, aerospace, and lifecritical systems. Today, even in consumer electronics, designers are looking at alternative technologies that are able to minimize costs incurred through field repairs or liability issues in the event of a device failure.

Hyperboloid wire basket connector technology has for a long time been used by the rail industry due to its ability to carry high currents and maintain signal integrity even under extreme levels of shock and vibration. The technology, now miniaturized to deliver high-density interconnects, has been widely adopted by the military market, and has started to take hold in the medical and highend consumer markets.

The Hyperboloid Wire Basket Connector features a contact sleeve,which is formed by wires strung at an angle to the socket’s axis, forminga hyperboloid cage. When the pin is inserted into this sleeve, thewires stretch around it, providing a number of linear contact paths.

The hyperboloid wire basket connector features an advanced contact design that satisfies performance requirements previously considered impossible. Further, it reduces perceived risk due to possible failure, and lowers cost of ownership in high-value electronics.

Due to the inherent design of the hyperboloid wire basket, connectors based on this technology offer the ability of the contact to withstand extreme levels of shock and vibration without compromising data or electrical integrity, even when measured as low as 5ns. When compared to other technologies, these connectors can provide long contact life, low insertion and extraction forces, low contact resistance, high current capability, and low power consumption.

High performance is ensured by the shape of the contact sleeve, which is formed by wires strung at an angle to the socket’s axis, forming a hyperboloid cage. When the pin is inserted into this sleeve, the wires stretch around it, providing a number of linear contact paths. When subjected to shock and vibration, these multiple contact lines provide a 360° wrap that ensures signal integrity is maintained even when measured as low as 5ns. Further, in harsh environments subjected to dust or ingress, should contact be broken at one or more points, there are many more points of contact available due to the linear contact path of each wire.

Smooth light-wiping action of the hyperboloid wire basket cage wires as the pin is inserted provides contact longevity. By minimizing wear due to the gentle action of the contact wires flexing around the pin, the hyperboloid contact can withstand up to 100,000 insertion and extraction cycles with negligible degradation in performance. A further benefit of this wiping action is a contact system that is self-cleaning.

Since the angle of the socket wires in the hyperboloid cage is inherently set by the design of the contact, tightcontrol of pin insertion and extraction forces is possible. The spring wires deflect smoothly to make line contact with the pin. This allows design engineers to significantly reduce subsystem size and weight by maximizing the density of the interconnect without being limited by insertion forces or requiring additional hardware to overcome mating and unmating forces.

Hyperboloid contacts have about half the resistance of conventional contact design, resulting in lower power consumption and reduced heat generation, which are important in power-sensitive applications or where heat generation causes problems in confined spaces. Weight and size of subsystems can also be further reduced as less cooling is needed.

Hyperboloid wire basket connectors offer design engineers contacts that carry small or very high currents, simply by modifying a few design parameters. Whether the contact carries low or high currents, there is little performance penalty as the contact resistance is inherently low. This flexibility is achieved by varying the number and diameter of the wires that make up the wire basket cage. As the number of wires is increased, the contact area is distributed over a larger surface of the mating pin. The high current carried by each wire, because of its intimate line contact with the pin, can be multiplied many times. Consequently, power and signal connectors are easily mixed in a single housing.

Although the competitive market faced by designers today is pushing the selection of less expensive components, it is not always true that cheaper is better. Often, the cheaper option has a higher failure rate. However, in many applications, failure can cost much more and can even put lives at risk, as is the case in mission-critical systems such as those in aerospace, military, and medicine. In such sensitive applications, designers put reliability above all other requirements, and the arguments for high performance and reliability are well understood.

In non-critical applications such as portable electronics, consumer devices, and some medical equipment, the perceived risks are not as obvious. If the connector fails, it becomes the weakest link in the product and jeopardizes the reliability of the device. Designers need to consider user expectations to determine how much they need to invest in interconnect components. For example, criteria such as how clean the operating environment is, expected mating cycles over the product lifetime, and whether water or liquid ingress is a problem need to be considered.

This article was written by Mark Wilkinson, Global Industry Director, Military & Aerospace, at Hypertronics Corporation. For more information, call 1-800-225-9228 or visit Hypertronics on the Web at: www.hypertronics.com .