Communications between electronic components employ one of a number of signaling schemes. Generally, digital communications use one of two classes of signaling schemes: single-ended or differential signaling. A single-ended signaling channel employs transmission of n-level (typically 2-level) signals through a single signal conductor, using a ground or power conductor as the reference for the signal conductor. Single-ended signaling requires only one signal conductor per channel, but presents difficulties such as simultaneous switching noise (SSN). Differential signaling mitigates SSN (and other issues) through the use of two complementary signal conductors with n-level (typically 2-level) signals of opposite polarity.
This invention is a new form of signaling, Zero Sum Signaling (ZSS), in which a parallel bus of channels can be created with the simultaneous switching noise (SSN) mitigation of differential signaling, but with a reduced number of conductors, approaching the single-ended limit.