# SpiTran User Guide

### Introduction

The s2ibis2 program from NCSU will produce an IBIS file containing a model for a component and all of the buffers used by the component. It derives buffer model information from simulations of SPICE buffer models. SpiTran is designed to provide the input files that s2ibis2 needs to create an IBIS model for one SPICE buffer model. The resulting IBIS buffer model can be inserted into an IBIS component model file, along with other required buffer models.
To do it's job, s2ibis2 requires:

- A SPICE file containing the SPICE buffer to be simulated, as well as other files that are included by it.
- An s2ibis2 control file, usually having a .s2i extension. The format of this file resembles the IBIS format.

SpiTran will produce these files for you, and then run s2ibis2 for you.

### The Life of a SpiTran Project

SpiTran produces some files, and s2ibis2 produces even more files. So SpiTran creates a new directory for each project. Your SPICE buffer model file is copied into the project directory, to insure that the original file remains unaltered. At this point it is likely that your SPICE model file is not arranged such that s2ibis2 is able to use it. The file is checked for statements that could cause problems for s2ibis2, and you are given the opportunity to fix these. Then, a top level test fixture SPICE file is created. This forms a wrapper circuit for your SPICE file, and is in a format that s2ibis2 can use. A dialog allows you to enter all of the information for creating the s2ibis2 input file, and then you are ready to run s2ibis2. Once the IBIS file has been produced you should check it, and possibly insert the buffer model into another IBIS file.

### Step by Step

Click on the items below to view the details of each step.

1. Creating a New SpiTran Project
2. Opening an Existing SpiTran Project
3. Configuring a Top Level Circuit
4. Setting Up Translation Options
5. Running the Translation
6. Checking and Using the IBIS Model File
7. Finishing Up

At any time you may choose User Guide from the SpiTran Help menu to open this document in a web browser.

### Troubleshooting

See the SpiTran Troubleshooting Guide if you have trouble.