Timing-Driven Row-Based Power Gating

In this paper we focus on leakage reduction through automatic insertion of sleep transistors using a row-based granularity. In particular, we tackle here the two main issues involved in this methodology: (i) Clustering and (ii) the interfacing of power-gated and non power-gated regions within the same block. The clustering algorithm automatically selects an optimal subset of rows that can be power-gated with a tightly controlled delay overhead. We then address the issue of interfacing different gated regions and propose a novel technique to address this issue with minimal area and power penalty. Our approach is compatible with state-of-the art logic and physical synthesis flows and it does not significantly impact design closure. We achieve leakage power reductions as high as 89% for a set of standard benchmarks, with minimum timing and area overhead.