Incorporating Backchannel Training into Signal Integrity SerDes Compliance

Abstract

Performed automatically by SerDes hardware, backchannel training is an essential part of signal quality in high performance serial link interfaces. Until recently, there has been no standard way to model this behavior in serial link simulations with commercial tools. But recent enhancements to the upcoming IBIS standard now support backchannel training, enabling IBIS-AMI models to emulate this real-world SerDes behavior. Signal integrity simulations will now have the ability to incorporate backchannel algorithms into their IBIS-AMI models, automating the optimization of transmitter and receiver equalization settings in the same manner as their actual SerDes hardware devices. This will save system designers significant time by avoiding a multitude of computationally intensive sweeping in order to determine optimum equalization settings for their link, while at the same time yielding more realistic and higher quality results that are more consistent with the hardware they seek to model.