EDA to STEP FAQ

Q. Can you explain a bit more about STEP?

Q. Why AP 203 and not AP 210 which is for electrical assemblies and packages?

Q. Which 3D MCAD tools read in STEP?

Q. My STEP files are way too big. What can I do?

Q. What does STEP do for me that IDF does not?

Q. Can I pass mechanical material and electrical properties via STEP?

A. STEP stands for "Standard for the Exchange of Product model data" It is actually ISO 10303. Our concern is only with a small part of the standard - in particular AP (application protocol) 203 which is the 3D geometric description. For a in depth understanding of STEP (it is pretty damn complex) I can recommend the Wikipedia page: en.wikipedia.org/wiki/ISO_10303

A. Because it appears that 3D MCAD tools read AP 203 (and AP 214) and we have found no one who reads AP 210.

A. We are in the process of verifying which MCAD tools read STEP. We know that the major ones all do. What we don't know is how well they import the STEP data and that will "trial and error" to determine.

A. This is the $64,000 question. 3D files coming from 2D multi-layer EDA data are going to be large. Very large. You can do a few things:

a) just translate the part (or parts) of the design you need. For example, if you need to test the fit of a PCB and its components in your subassembly then make sure you only translate the board and its thickness and the components and the mounting holes. Don't translate the copper traces or drill holes.




a) Control your resolution - PCBs have a lot of curved data. Arcs generally get "fractured" into multiple small segments during conversion. The more segments, the better the approximation but the bigger the 3D data file. First you have to know what resolution is acceptable in 3D and second you have to know how to control it during the conversion. Also, some features may need better resolution than others.

While it is easy to give you these directives it is not so easy to implement them. However our conversion tools will provide various controls to either select the data to be translated and/or control the resolution for arcs and circles.

A. That depends. If you have a PCB layout tool that produces IDF and you have a MCAD system that reads it you may already be in good shape. However if the IDF reader in the MCAD tool is poorly implemented you may be out of luck. This applies especially for very large designs where your IDF flow does not include enough controls to limit the data size. Also, to my knowledge, you will not get circuit features via IDF. (Even though IDF 4.0 supports such features we know of no flows that implement IDF 4.0)

A. Hypothetically the answer is yes. In practice? No. While the STEP AP 203 protocol can accept various attributes that could be used to pass this information you are depending on the receiving MCAD system to recognize those attributes. This is unlikely. It will require a level of cooperation by the MCAD software people that is unlikely and would require us to customize the STEP output for a particular target.

If there are "targets" such as Ansys simulation tools that benefit from transmission of material and electrical properties we would be glad to offer a flavored version of STEP assuming they have made provisions to read this information.