Operational characteristics of a CMOS microprocessor system at cryogenic temperatures

✍ Scribed by M.J. Deen; C.Y. Chan; N. Fong

• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 266 KB
• Volume: 28
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/0011-2275(88)90024-0

✦ Synopsis

In this Paper, the variation of the maximum input clock frequency versus temperature of a CMOS microprocessor with a "piggy-back' EPROM is described. The maximum input frequency for reliable operation increased from 19 to 33 M Hz as the temperature was lowered from 300 to 77 K, and there was a corresponding increase in the power dissipated from 18 to 25 mW using a supply of 5V. The measurements were repeatable even after thermal cycling more than 10 times and showed no hysteresis on cooling down to 77 K or warming up to 300 K. The results obtained can be qualitatively explained as due to a combination of effects including the increase in the carriers' mobilities, the decrease in junction capacitance, and the decrease in the interconnect resistance with decreasing temperature.