Analysis of delay mismatching of digital circuits caused by common environmental fluctuations

Environmental conditions are changing all the time along the chip as a consequence of its own activity, provoking deviations on propagation time in digital circuits. In future technologies, the increment of devices sensitivity to environmental fluctuations yields to a wider range of possible time deviations, being for example, in an NOT gate designed in a 16 nm technology 1.6 times larger than for a 45 nm version. But this ratio is different for every circuit cause it depends on its fundamental structure and characteristics. In this paper the tendency of timing parameters deviations due to environmental factors fluctuation and how these deviations have deeper impact on more complex structures are analyzed. It is shown that the internal structure of the logic gates cause a mismatch between logic circuits and in future technologies it will be enlarged.