Hybrid interconnect network for on-chip low-power clock distribution

Clock is regarded as the heartbeat of modern synchronous digital integrated circuits. However, with the CMOS technology shrinking, it becomes critical to deliver high-quality global clock signal with low propagation delay and hence conventional metallic interconnect seems to meet its bottleneck, as a clock distribution network (CDN) might consume up to 50% of the overall power. To address these problems, this Letter proposes a novel combination of wireless and conventional metallic interconnect to improve the performance of on-chip clock distribution. By incorporating integrated wireless clock transceivers and efficient modulation technique, overall performance has been increased significantly with a total delay reduction of 66.8% compared with a new cornerstone tapered H-tree model from 400 to 130 ps. In addition, clock uncertainties are now predictable according to the displacement of transceivers,,33 ps of clock skew at 2.5 GHz input with highly unbalanced loads could be found within the proposed CDN, and hence, indicates a promising potential of future high-performance on-chip clock distribution.