A High Throughput, Metastability-Free GALS Channel Based on Pausible Clock Method

Mohammad Ali Rahimian,  Siamak Mohammadi,  Mohammad Fattah

Dependable Systems Design Lab, School of ECE, University of Tehran, Tehran, Iran

Abstract

Synchronization issues such as metastability in multi-clock domain systems have become a big problem, reducing data transmission throughput between domains. In this paper, a high-throughput, metastability-free data transmission channel based on pausible clock method in Globally-Asynchronous Locally-Synchronous (GALS) systems is proposed. This channel can be used as the interconnection of mixed-clock synchronous IP cores without having concerns about their synchronization. We show that the probability of metastability in our design is practically zero; and this without loss of throughput and latency, allowing the transmitter and receiver to operate with their own maximum clock frequency. The proposed channel is simulated in 90nm CMOS process using Predictive Technology Model (PTM) library. Gate delays and power parameters are extracted from Spice simulations and are back annotated into our channel HDL code. The throughput, latency and power are analyzed and compared with existing designs.