Pre-driver PDN SSN, OPD, data encoding, and their impact on SSJ

This paper describes the simultaneous switching noise (SSN) behavior of pre-driver power distribution networks (PDNs) excited by different kinds of simultaneous switching output (SSO) signal patterns. The physics behind the PDN resonance is explored and the quantitative relationship between pre-driver PDN resonant frequency and signal toggling frequency is established to find the SSO signal pattern that generates the worst PDN SSN. This paper shows how and why on-package decoupling (OPD) and data encoding can greatly reduce pre-driver PDN SSN as well. Additionally, the relationship between pre-driver PDN SSN and SSO jitter (SSJ) and a method for finding the worst SSJ due to pre-driver PDN SSN effect is discussed.