Zuken Announces S-Parameter Support for SI Analysis

To analyse high-speed signals in applications featuring DDR2/3 or USB technology, accurate models for components such as common-mode filters, baluns, and connectors are required. At today’s bit rates, simple RLC models of such components are no longer appropriate. Accurate simulation at frequencies into the multi-gigahertz range is required, using models that reveal the minimum amount of information about the internal component structure.

S-Parameters, a behavioural concept well known in radio frequency design, are ideally suited for this purpose. They represent the transmission and reflection behaviour of waves at specific frequencies, using industry standard formats such as Touchstone, which has also been adopted by IBIS (I/O Buffer Information Specification).

The signal integrity (SI) analysis within CR-5000 Lightning is performed by time-domain simulation that works in conjunction with design capture and physical layout. Therefore the frequency domain S-Parameter models are first transformed into compatible macro-models which are then imported into the simulation library. The transformation is only done once and the resulting model can be used for SI verification without the need for any detailed knowledge of the original S-Parameter set. This provides an easy-to-use flow to layout engineers, who may not be familiar with S-Parameter based modelling.

For the implementation of this new functionality, Zuken has teamed up with IdemWorks s.r.l., Italy. This high-tech start-up is well known for its competence in S-Parameter based modelling. The easy-to-use transformation tool provided by IdemWorks generates Zuken-specific, robust time domain macro-models with a few button clicks, taking care of sophisticated requirements such as model passivity and causality. It also provides port reduction to ensure fast and easy to use models that focus on real designer needs.