Reliable circuit operation at high temperature is required for several high-tech industries most notably: automotive control, space craft micro-electronics, the food industry, oil and gas exploration, and multi-phase chemical reactors like those used in the pulp and paper industry. Many applications require analog, mixed-signal, and digital electronics to operate at elevated temperatures to support and process sensor data.
Nima Sadeghi is a Ph.D. student in the Systems-on-a-Chip Research Laboratory. Working with Professor Shahriar Mirabbasi, Nima designed the building blocks of an electronic sensor interface for high temperature applications. The chip Nima developed will be use in a wood chip digester in the pulp and paper industry. The smart chip sensor will follow woodchip flow through the reaction vessel and record important internal process parameters such as pressure and temperature over time. This information will be used to optimize reactor performance and improve the quality of the pulp produced. The temperature inside the digester can reach 180 degrees Celsius so the sensor system needs sensors and electronics that can withstand high temperatures.
Minimizing the power consumption of the high temperature design was Nima’s first intention. He also took advantage of the reduction in size possible with System-on-a-Chip design, since off-the-shelf components could not satisfy the size requirement for this industrial application. Furthermore almost all commercially available high-temperature circuitry use non-standard transistor processors which are more expensive than the standard transistor technologies.
Nima has completed the design, modeling and development; he has fabricated three chips and measured the first two over the wide range of temperatures. Using an insulated crucible he can replicate the extreme temperatures the chip will be exposed to. Nima created a novel generic temperature compensation technique that has been filed as an invention disclosure to UBC’s University-Industry Liaison Office for provisional patent approval; in addition, part of Nima’s research and measurement results have already been presented in several prestigious IEEE conference and journal publications.
A 2.5 V 0.13 μm CMOS Amplifier for a High-Temperature Sensor System| Sadeghi, N., Mirabbasi, S. and Bennington,C.