The Dialog for STEP 3D Export

Abstract

STEP = STandard for the Exchange of Product model data

Find the dialog for the STEP Export in menu:
File|Input/Output Formats|File transfer/documentation|Step export(3D)...

Image 1: The Step Export Dialog as it opens. It consists of the main sections Schnellauswahl und Details.

The section Quick selection

In externem CAD die komplette Platine für das Gehäuse überprüfen
Diese Option verwenden Sie, wenn Sie den kompletten Aufbau (Platine incl. Bestückung) exportieren möchten. Es fehlen nur die inneren Details im Platinenkörper, die man von außen nicht sieht. Die Massefläche fehlt hier, kann aber noch hinzu gewählt werden.
In externem CAD nur die reine Platine für das Gehäuse überprüfen
Diese Option verwenden Sie, wenn Sie nur den Platinenkörper, also das, was gemeinhin in FR4-Material gefertigt wird, exportieren möchten.
Platine mit externen Werkzeugen elektrisch überprüfen
Hier übergeben Sie den Platinenkörper mit allen inneren und äußeren technischen Details (Leiterbahnen, Pads, Vias, Bohrlöcher...) ohne Bauteile.

Der Dialogbereich Details

Die folgenden Reiter können gewählt werden:

AP = Application Protocol

An AP covers a particular application and industry domain:

• AP 203 Configuration Controlled Design
• AP 210 Electronic Printed Circuit Assembly, Design and Manufacturing
• AP 214 Core Data for Automotive Mechanical Design Processes

Only some APs are implemented in your 3D program. AP 203 is a basic AP which at least will be supported by your system. You will notice only one difference in the data:

• STEP AP 203: single-colored
• STEP AP 210: four-colored

Selection

In tab Selection determines which elements are going to be overgiven to the STEP format. No changes have taken place here since the last version.

Detail truth

Components in color or monochrome.

Output PCB outline with exact coordinates:
The normal algorithm to calculate the PCB outline shows an inaccuracy of some µm. The outline of the PCB optionally can be calculated by a more accurate algorithm.

The outline of the PCB is calculated by an algorithm which shows an impreciseness of a few µm. You can select a precise algorithm which avoids this.

Output ground plane:

A ground plane can be converted to STEP though in the TARGET 3D viewer upt to now (may 2014) it can not be displayed. Activate this box if indicated.

Output details for simulators (conducting via hull and solder with THT):

Abundance of details goes along between the poles of necessity and file size. To simulate the electrical behaviour of the 3D PCB sufficiently details are needed. Tick the box here so that the STEP exportembraces it accordingly. Ground planes and assemblies are ticked automatically. The quick selection also ticks the required boxes automatically. "Components" are unticked because they aren't needed for simulation.

The layout of the printed circuit board, the placement of the components and the structure of the power layer can have its own effect on the electrical performance of the circuit. There may be problems with EMC, power integrity and signal integrity. Below you will find helpful links on the subject. By this means you can analyse your board on such effects for example using the simulation tool CST.

https://www.cst.com/Products/CSTPCBS
https://www.cst.com/Applications/Category/Signal+Integrity+and+Power+Integrity
https://www.cst.com/Applications/Article/Signal-Integrity-Analysis-Of-A-Complex-Multi-Layered-Package
http://en.wikipedia.org/wiki/Signal_integrity
http://en.wikipedia.org/wiki/Computational_electromagnetics

Sizes (= parameters)

Extras

Using the option "Generate assemblies the STEP-Import in your CAD might show a hint e.g. in Rhinoceros

In your CAD there will be a function "Explode", which is able to divide objects in a hierarchy (cascading).

PIC exploded:

Importantelement groups san be divided into various sub entities. A first explosion separates the following objexts:

• PCB body
• electroconductive objects (Tracks, Pads, Vias, Ground planes...)
• component 1
• component 2
• component ...

In this first stage of explosion within your 3D CAD system it is possible to assign material properties (e.g. "copper") to the electroconductive objects of your projects. Now let the electroconductive parts explode again so that single signals for instance can be touched/inspected/treated separately (galvanic separation).

Approximations

Some 3D programs offer only a rudimentary STEP import. Some STEP surfaces e.g. CYLINDRICAL_SURFACE are not implemented or inaccurate. These surfaces can be approximated by a polyhedron; i.e. made up of only PLANEs.

File load time

It takes some minutes to load a STEP file! This load time increases if some polyeder approximations are applied. A 3D viewer does the import much faster than a 3D-CAD program! Currently implemented STEP elements: CARTESIAN_POINT, VERTEX_POINT, LINE, CIRCLE, PLANE, CYLINDRICAL_SURFACE, TOROIDAL_SURFACE, SPHERICAL_SURFACE, DIRECTION, VECTOR, AXIS2_PLACEMENT_3D, ADVANCED_FACE, FACE_BOUND, FACE_OUTER_BOUND, ORIENTED_EDGE, EDGE_CURVE, EDGE_LOOP, CLOSED_SHELL, MANIFOLD_SOLID_BREP, STYLED_ITEM, MECHANICAL_DESIGN_GEOMETRIC_PRESENTATION_REPRESENTATION

Switch off all options to reduce load time in Solid Edge: