A few weeks ago VORAGO Technologies issued a press release to announce that our VA10800 microcontroller had just surpassed 4000 hours of successful operation at 200C. The level of interest that we have received has been incredible. Clearly there are a lot of folks out there who want to operate their electronics at temperatures beyond the standard industry specifications.
There are a few reasons driving this demand. If electronic components can withstand a higher temperature, often expensive and bulky shielding and cooling systems can be minimized or discarded. Overall system cost can be reduced significantly. It is cheaper (and more reliable) to use a chip that is specified to operate at higher temperatures than pay for a cooling system comprised of forced air, liquid cooling, peltier plates, elaborate heat sinks or other means.
Another reason is that it is that systems can usually be optimized by positioning components such as sensors and microcontrollers close to the action. Take for instance a temperature or pressure sensor that is used in a jet engine. High temperature comes with the territory. It has long been a source of frustration for systems designers to locate the sensors in a high temperature environment but the microcontroller has not been able to operate in extreme heat. The high temperature VA10800 has moved the goalposts and it is now possible to position a smart sensor (consisting of the sensing element and MCU) in an extreme temperature environment.
High temperature devices are also very interesting for product reliability. Temperature is a significant accelerator for operating lifetime. An Arrhenius curve can be plotted to show that a device that can operate at a high temperature for a certain amount of time can operate reliably for much longer at a lower temperature. This is important in many application that perhaps do not need to live at 200C, but need to be absolutely rock solid at (say) 150C for many years.
Finally, another reason that was cited to me about why the 200C VA10800 microcontroller was of interest to a system designer, was that they could avoid 'up-screened' parts. An up-screened device is a component that that was not designed for high temperature but has been tested an appears to operate OK. Due to process variations, there will always be outliers that behave outwith the general specification. Using up-screened parts is not ideal as they are not recommended or guaranteed by the original manufacturer, they are not designed for purpose, the manufacturing process that created the outlier is not repeatable and 'walking wounded' can be created during the up-screening process. It is also just as expensive to obtain up-screened devices as it is to buy a real part from VORAGO.
By the way, the press release didn't mention that there was also another oven running VA10800 micros at 225C that had just surpassed 2000 hours. Our goal is to keep pushing the envelope of operation with our ARM Cortex microcontrollers in conditions of extreme temperature and radiation.