Know SPICE to use SPICE

Discussion created by weston_beal on Apr 29, 2011

HyperLynx is very easy to use compared to other simulation tools. That ease of use sometimes lulls people into the trap of thinking that HyperLynx will take care of all the difficulties of using SPICE models. It definitely makes it easier in general, but you usually need to know SPICE syntax in order to get a model adapted to HyperLynx the first time. Most SPICE models are provided with the expectation that you will use the model in a circuit file that you edit manually. This requires some knowledge of SPICE, or a good document describing how to use the model. In order for HyperLynx to implement a SPICE model, the model must be in a consistant format that HyperLynx can deal with programatically. You might need to change the files syntax to put the necessary parts of the circuit into a .subckt block. This is the main task that requires knowledge of SPICE syntax. SPICE is a little like a programming language, and a model is a software library provided by a third party. You need to know the interface parameters, what is expected as inputs, and what is expected as outputs. As a signal integrity engineer it is worth your time to learn SPICE syntax, even if you use a GUI based tool like HyperLynx to set up and run simulations.