Wyniki badań działania układu ATXmega64A3 w niskich temperaturach

• Autorzy: Michalak S.

Warianty tytułu

EN

Research results of ATXmega64A3 operation in low temperature

• Języki publikacji: PL

Abstrakty

PL

W artykule przedstawiono wyniki badań dotyczące pracy 8/16-bitowego mikrokontrolera ATXmega64A3 w warunkach kriogenicznych (w temperaturze 77K). W przeprowadzonych eksperymentach obserwowano zachowanie wewnętrznych oscylatorów 2 MHz (oscylator RC) i 32 MHz (oscylator pierścieniowy). Potwierdzono zdolność do prawidłowego działania w tak niskiej temperaturze, a także możliwość zwielokrotnienia sygnału zegarowego z wykorzystaniem pętli PLL, porównano wydajność obliczeniową układu dla różnych warunków pracy.

EN

In this paper the results of experiments with an 8/16-bit ATXmega64A3 microcontroller (ATMEL) at low temperature are presented. The examined devices were immersed in a Dewar flask with liquid nitrogen (Fig. 1). First of all we focused on internal oscillators. There are four types of oscillators inside a microcontroller and we tested two of them: 2 MHz RC and 32 MHz ring oscillator. The results at 77K (liquid nitrogen) were compared to the results at 300K (room temperature). The frequency as a function of the supply voltage for 300K and 77K is shown in Fig. 2 and Fig. 3, respectively. According to the theory of silicon semiconductors, the activity of carriers increases in low temperatures, so there was expected increase in the oscillation frequency. For the ring oscillator (32 MHz) our expectations of the growth of the frequency were confirmed. Due to PLL there was a possibility to increase the frequency, and we reached 64 MHz. Figs. 4 and 5 show the frequency as a function of the supply voltage at 77K in detail. The power consumption was also measured (Fig. 6). With increase in the frequency the increase in the power consumption was obtained (Fig. 7). The value of the power depends on the supply voltage strongly, while on the temperature less, so the results at 300K and 77K do not differ too much (Fig. 8). We also calculated the energy efficiency for the microcontroller under various conditions. The frequency to power coefficient was defined, and the results are shown in Figs.9 and 10. The energy consumption for the example task was estimated (Tab.1) and verified by experiments.

Słowa kluczowe

PL

mikrokontroler; ciekły azot; wydajność obliczeniowa

EN

microcontroller; liquid nitrogen; energy efficiency

• Wydawca: Wydawnictwo PAK
• Czasopismo: Pomiary Automatyka Kontrola
• Rocznik: 2012
• Tom: R. 58, nr 11
• Strony: 944--946
• Opis fizyczny: Bibliogr. 6 poz., rys., tab., wzory

Twórcy

autor

Michalak S.

• Politechnika Poznańska, Wydział Elektroniki i Telekomunikacji, ul. Polanka 3, 60-965 Poznań,

Bibliografia

• [1] 8/16-bit AVR XMEGA A Microcontroller. XMEGA A Manual, www.atmel.com
• [2] AVR1506: Xplain training - XMEGA clock system. Application Note, www.atmel.com
• [3] Arnold K.: Properties of internal RC oscillator of ATmega16A structure at low temperatures, International Cryogenic Engineering Conference 23 - International Cryogenic Materials Conference 2010 (ICEC23/ICMC2010), Wrocław, Poland, 2010.
• [4] Colonna-R, L. M., Deverell, D.R.: Operation of a CMOS micro-processor while immersed in liquid nitrogen, IEEE J. Solid-State Circuits SC-21 (3), pp. 491-492, 1986.
• [5] Vassighi A., Keshavarzi A., Narendra S., Schrom G., Ye Y., Lee S., Chrysler G., Sachdev M., De V.: Design Optimizations for Micro-processors at Low Temperature. Design Automation Conference, Proceedings, 41st, pp. 2-5, San Diego, 2004.
• [6] Daga J. M., Ottaviano E., Auvergne D.: Temperature Effect on Delay for Low Voltage Applications. Design, Automation and Test in Europe, IEEE Proceedings, pp. 680-685, 1998.