Researchers at the Universities of Bristol and Southampton are working on an entirely new type of high-temperature control system for aircraft alongside Moog Controls and the Bristol design centre of US chip designer Microsemi.

The £1m NEMICA project is backed by UK government funding agency Innovate UK to address the challenges of high-temperature electronics design using tiny relays just a few microns in size (as shown in the main picture, above). These nanoelectromechanical (NEM) devices are built with existing silicon chip technology and can be used for memory chips and programmable logic arrays in high-temperature environments.

“By using electro-mechanical switches as the basic building block some 200 years after Babbage proposed his original fully mechanical calculator”

 

“NEM relays have practically zero leakage, an abrupt turn-on transient and a high on-current, and can also be integrated with CMOS at the die or wafer level. This makes them promising candidates for digital logic implementation in ultra-low power applications,” said Dr Dinesh Pamunuwa, Reader in Microelectronics in the Department of Electrical and Electronic Engineering at the University of Bristol who has worked on the technology for the last five years. “By building a functioning NEM relay-based processor we would go full circle by using electro-mechanical switches as the basic building block some 200 years after Babbage proposed his original fully mechanical calculator.”

Collaborating on chip design

Microsemi in Bristol includes chip designers from Zarlink, Mitel and Plessey, while Moog Controls has designers in Tewkesbury and Southampton. Microsemi will develop new types of programmable logic arrays using the technology.

Microsemi Corp. announced a new collaboration with Moog Controls Limited, University of Bristol and Southampton University based in the U.K. The collaboration, named NEMICA, aims to address the challenges associated with high temperature electronics design by leveraging each organization's unique expertise in this area. (PRNewsFoto/Microsemi Corporation)

The three-year NEMICA project is initially allowing existing designs to work at elevated temperatures of 175°C and then move to 225°C using new field-programmable gate arrays (FPGAs) based on the NEM technology developed at Bristol and Southampton who originally worked with IBM Zurich to build the miniature relays.

“We are pleased to be part of this top-tier collaboration as our collective group looks to develop industry-leading re-programmable memories and gate arrays based on nanoelectromechanical technology that are capable of withstanding long-term exposure to high temperatures and harsh environmental conditions,” said Jim Aralis, chief technology officer and vice president of advanced development at Microsemi.

Dealing with high temperatures

System designers face considerable challenges when designing control systems operating in high-temperature environments. To achieve ideal performance levels in terms of system efficiency and safety, engineers must relocate the controller closer to the points of monitoring and output. In most systems this is easily achieved because the environment is ambient and harmonised. However, in applications where the sensor and the actuator are in high-temperature areas at over at 200°C, it is not always possible to place conventional electronic control systems near the sensor and actuator.

To overcome this problem, system engineers must place the controller in a cooler region. This normally entails designing new high-temperature connections systems, interfaces, signal conditioning and protection to maintain the integrity of the data being collected and of the electronic instruction back to the actuator. The alternative is to provide cooling systems which otherwise do not add any value to the system. All of this adds cost, weight and delays in the system response.

The high-temperature controls using NEM devices avoid all of this, providing lighter, cheaper, more reliable electronic systems.

Nick Flaherty