Jihong Ren, Rambus
Sam Chang, Senior Member of Technical Staff, Rambus
Dan Oh, Senior Manager, Rambus

Accurate analysis of link performance including deterministic and random effects as well as advanced signal conditioning schemes is crucial in modern high-speed I/O design. In recent years, statistical link performance tools such as Linklab and StatEye, and fast time-domain simulation tools such as IBIS Algorithmic Modeling Interfaces (AMI) are introduced to efficiently co-simulate deterministic and random effects as well as advanced signaling schemes. However, these statistical and time-domain approaches have limitations in terms of their capability of accurately simulating system nonlinearity, general jitter, jitter tracking as well as coding. In this paper, we present a hybrid approach that combines statistical and time-domain techniques to efficiently overcome these limitations. It has several key contributions: 1) capture system nonlinearity using multiple-edge responses (MER), a fast time-domain method; 2) separately simulate deterministic and random jitter, one in time-domain to capture jitter nonlinearity and the other in statistical domain to capture tail statistics; 3) co-simulate signal and power integrity to include simultaneous switching output noise (SSO) which is one of the major limiting factors for single-ended signaling systems such as GDDR5; 4) co-simulate clock and data channel to correctly capture jitter tracking in source-synchronous systems. We demonstrate this hybrid approach by studying the jitter tracking capability of clock forwarding and effectiveness of various coding schemes in terms of system bit error rate.