Touchstone file
A Touchstone® file was originally a proprietary file format for the eponymous frequency-domain linear circuit simulator [1] from EEsof, launched in 1984. The simulator itself has long since been superseded[2], but its file format lives on. A Touchstone file (also known as an SnP file) is an ASCII text file used for documenting the n-port network parameter data and noise data of linear active devices, passive filters, passive devices, or interconnect networks. An example of the S-parameter section is here. Touchstone file format later became a de facto industry-standard file format not only for circuit simulators but also for measurement equipment (e.g. vector network analyzers, or VNAs), then later still an EIA standard (part of the IBIS (I/O Buffer Information Specification) project). On April 24,2009, the IBIS Open Forum ratified version 2.0 [3], superceding Version 1.1 [4]. Several enhancements to the file format, which allow additional description of the non-linearity of the component, have been proposed[5] under the P2D, S2D and, more recently, X-parameters [6] representation.
Notes
- ^ History of EEsof and Touchstone at Microwaves 101
- ^ It was replaced by "W2200 Advanced Design System (ADS) Core".
- ^ [http://www.eda.org/ibis/touchstone_ver2.0/touchstone_ver2_0.pdf Touchstone® File Format Specification Version 2.0]
- ^ EIA IBIS Touchstone Spec 1.1
- ^ E8854A RF System Models from Agilent EEsof EDA
- ^ Agilent NVNA & X-Parameters Simulation in ADS: The new paradigm for nonlinear measurements, modeling, and simulation with ADS of nonlinear components
Trademark Notice
Touchstone is a registered trademark of Agilent Technologies, Inc. X-parameters is a trademark of Agilent Technologies, Inc.