maximum current estimation considering power gating
As semiconductor technology scales down, the leakage power will soon become comparable to the dynamic power. To reduce both dynamic and leakage power, power gating in addition to clock gating should be used because clock gating saves only dynamic power. The knowledge of maximum current is needed to design high-performance and reliable circuits using power gating. However, all existing techniques for maximum current estimation are not applicable to power gating. In this paper, we study the maximum current estimation problem considering power gating. We develop two algorithms based on automatic test pattern generation (ATPG), and apply them to ISCAS'85 benchmarks. Experiments show that our new estimation algorithms can finish the largest benchmark circuit within ten seconds, and achieve up to 87\% larger current when compared to an existing ATPG-based estimation algorithm that is able to obtain maximum current estimation 6\% less than the theoretical maximum current without considering power gating. This implies that power gating may lead to a larger maximum current when compared to the normal maximum switching current, and open a new avenue for maximum current estimation as well as circuit reliability research.
power gating atpg low-power design power estimation