Escalator Network for a 3D Chip Stack with Inductive Coupling ThruChip Interface

Abstract

A wireless inductive coupling ThruChip Interface (TCI) is a flexible system-in-package (SiP) technique which enables to build a powerful interconnection network between stacked chips. For easy use of TCI, we have developed intellectual properties (IPs), and proposed an interconnection network which can make the use of IPs. We also developed a real chip embedded the IP, and evaluated the performance. By stacking multiple chips with the proposed IP, an inter-chip network with link-to-link flow control by piggyback control is established. The new proposed escalator network which uses piggyback of the credit packets outperforms the ring network used in the first prototype by 28%-59% in terms of throughput. The performance overhead by the piggyback control was less than 3%-4% of that without control messages.