Bob Stanton explores how electronic circuits that are serving communications, surveillance, data processing, sensors and controllers are in the midst of a revolution
High-end military, medical and industrial industries depend on more data and want it faster. In response, data processing is evolving to develop increased bandwidth data transceivers capable of transmitting up to 10 Gigabits per second. Semiconductor companies are building chips to handle newer data processing standards. High-density CMOS chips swing signal rates more rapidly, GaN (Gallium Nitride) chips operate at 10 Gbit/sec., and MEMs chips combine electrical and physical functions.
Single-ended cable transmission is being replaced with differential signalling using twisted-pair wiring that interfaces with serialisation clocks embedded in the receiver circuits. Connectors and cable now serve low voltage differential signal (LVDS) systems instead of the older TTL circuitry. The LVDS circuits operate in the 3-5V range, which reduces time, significantly increases signal transmission speed and reduces electromagnetic interference problems. All this has stimulated an explosion in the design and development of small, high-density, high-speed portable electronics.
adapting to new applications
To meet this demand, connector manufacturers, such as Omnetics Connector Corporation, now offer high-speed differential signal cable and connectors that feature micro- and nano-sized connectors and cable. Most designs originate from standard military connectors and are adapted to newer applications. Systems designers can select a connection system that mechanically fits their device and use solid modelling with the connector designer to quickly edit the model for physical size, mounting and mating specifications. Designers then review the cable signal and power supply requirements to ensure signal speed, performance match and impedance. Omnetics’ micro- and nano-connectors use high reliability beryllium copper spring pin-to-sockets that are gold-plated and tested to full military reliability specifications for wear, shock and vibration. Wiring used within the connector elements is laser trimmed and hard-crimped to avoid any solder technology problems.
Size and weight have become key elements for circuits used in applications such as small satellites, dismounted soldiers, remote controlled vehicles and medical instruments. Hybrid connectors carrying more than one type of signal help save space and weight by changing the connector insulator and matching pin to socket formats to serve each signal type. For example, power signals travel to and from the instrument using two power pins inside the same connector as multiple high-speed USB 3.1 signal cables that use smaller pins. The cable offers both types of signals while keeping the power circuit insulated from the signal group. This process reduces the need for multiple cables and connectors and saves size and weight. Micro and nano hybrid connectors are readily adaptable to specific applications in both rectangular and circular formats.
Applications currently using micro- and nano- connectors include future soldier communication electronics, ESA satellites, LIDAR surveillance and ranging devices, and even remote controlled bomb disposal robots. The medical industry is using nano-D connectors inside prosthetic devices for new limbs and hands.
The future is at hand and Omnetics is busy introducing nano-sized coax connectors designed for 50 ohm impedance and serving up to 20 GHz over 1m. These new RF connectors are also adding to the evolution of advanced circuitry, and shielding is an option that helps protect from cyber and electromagnetic interference. Omnetics retains an online design team and rapid prototype team to work within the demands of future circuitry. As the new chip and circuit technologies evolve and need interconnections between instruments and elements, we will see faster data transmission using milliamp signals at
very low voltages.
Bob Stanton is director of technology at Omnetics
