Detailed Interconnect Example
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Printed Circuit Board
Sample Part 21 Code
Interconnect Module product
#12=PRODUCT_CONTEXT('',#10,'mechanical');
#77=PRODUCT('test_design_interconnect','','',(#12));
#84=PRODUCT_RELATED_PRODUCT_CATEGORY('interconnect module','pcb',(#77));
#80=PRODUCT_DEFINITION_FORMATION('1','',#77);
#83=INTERCONNECT_MODULE('','interconnect module',#80,#21);
#21=PRODUCT_DEFINITION_CONTEXT('physical design',#10,'as designed');
A printed circuit board is nearly a synonym for printed wiring board, except that a printed circuit board may include printed components and a printed wiring board is totally interconnected without printed components. For the purposes of AP210 both have been mapped to the ARM concept of PCB and the AIM interconnect_definition entity. This recommended practice is limited to describing planar printed circuit boards and printed wiring boards.
In order to define an interconnect module for a PCB AO in AP210, five AIM entities are used. The product entity establishes its identification (or part number), name (or nomenclature), and description. Interconnect_definition entities define the physical design and physical design usage models of the interconnect module.
The product entity
AP210 identifies a PCB AO with a product entity that is referenced by the products attribute of a product_related_product_category entity with a name of "interconnect module" and by the of_product attribute of a product_definition_formation which is in turn referenced by the formation attribute of interconnect_definition entities.
The product context entity
The products frame_of_reference attribute references a product_context entity.
The product related product category
The product is referenced by the products attribute of a product_related_product_category entity with a name of "interconnect module".
The Printed Circuit Board Physical Design Usage View
The physical design usage view identifies a PCB AO as a part in its next assembly with sufficient detail to allow its use but without sufficient detail to permit reproduction of the printed circuit board.
AP210 defines the PCB Physical Design Usage View using three entities an interconnect_definition, shape_aspect and product_definition_shape. A shape_aspect entities define the interconnect modules primary, secondary and edge surfaces in the physical design usage model.
The interconnect_definition entity
The PCB physical design usage view is defined by an interconnect_definition entity whose frame_of_reference attribute references a product_definition_context entity with a name of "physical design usage".
The primary surface shape_aspect entity
AP210 specifies the primary surface feature of the PCB AO in the physical design usage view with a shape_aspect entity with a description of "interconnect module primary surface" that references a product_definition_shape entity that references the physical design usage views interconnect_definition.
The secondary surface shape_aspect entity
AP210 specifies the secondary surface feature of the PCB AO in the physical design usage view with a shape_aspect entity with a description of "interconnect module secondary surface" that references a product_definition_shape entity that references the physical design usage views interconnect_definition.
The edge surface shape_aspect entity
AP210 specifies the edge surface feature of the PCB AO in the physical design usage view with a shape_aspect entity with a description of "interconnect module edge surface" that references a product_definition_shape entity that references the physical design usage views interconnect_definition. The shape_aspect is referenced by the definition attribute of a property_definition entity. The property_definition is referenced by a property_definition_representation that references a shape_representation. If the shape is planar it represents a projection of the maximum extent of the interconnect module's edge onto the planar shape.
The interconnect module thickness property_definition_representation entity
AP210 specifies the thickness of the PCB AO in the physical design usage view with a product_definition_representation entity with a definition attribute that references a property_definition entity with a name of "located interconnect module thickness". The property_definition references a physical_unit_datum entity with an of_shape attribute that references a physical_definition_shape entity with a definition attribute that is the interconnect_definition. The physical_unit_datum is referenced by the rep_1 attribute of a shape_aspect_relationship entity with a rep_2 attribute that references a physical_unit_datum_feature entity with an of_shape attribute that also references the interconnect_definition's physical_definition_shape. The physical_unit_datum's of_shape attribute references the interconnect_definition. The property_definition is also referenced by the definition attribute of a property_definition_representation entity with a used_representation attribute that references representation entity with a items attribute that references two length_measure_with_unit_and_measure_representation_item complex entities one with a name of "maximum thickness" and one with a name of "minimum thickness" that both contain the boards thickness.
The Printed Circuit Board Physical Design View
Sample Part 21 Code
#21=PRODUCT_DEFINITION_CONTEXT('physical design',#10,'as designed');
#83=INTERCONNECT_DEFINITION('','interconnect module',#80,#21);
#258=NEXT_ASSEMBLY_USAGE_OCCURRENCE('','assembly composition','',#83,#123,$);
#123=COMPONENT_DEFINITION('','interconnect module edge',#80,#15);
#682=PRODUCT_DEFINITION_RELATIONSHIP('','design usage','',#83,#89);
#89=INTERCONNECT_DEFINITION('','interconnect module',#80,#88);
#88=PRODUCT_DEFINITION_CONTEXT('physical design usage',#10,'as designed
#80=PRODUCT_DEFINITION_FORMATION('1','',#77);
#22=STRATUM('top','',#80,#21);
The physical design view fully describes a PCB AO in sufficient detail to permit production in a manufacturing process and analysis of it's response to a simulated environment in a computer based experimental environment.
A component_definition entity defines the interconnect modules edge in the physical design model. Stratum entities define the PCB AO layers.
The interconnect_definition entity
The PCB physical design view is defined by an interconnect_definition entity whose frame_of_reference attribute references a product_definition_context entity with a name of "physical design" and assembly relationships with the printed circuit boards stratum and interconnect module edge definitions. It is related to the physical usage view by a product_definition_relationship entity with a name of "design usage". It has a property_definition that is the shape of the printed circuit board.
The component_definition
AP210 specifies the edge of the PCB AO in the physical design view with a component_definition entity related to the physical design views interconnect_definition by a next_component_usage_occurance entity. The component_definition has it's own product entity.
The interconnect module edge is specified as a Assembly_component AO that is mapped to the inter_stratum_feature subtype of the component_shape_aspect entity.
Sample Part 21 Code
Physical Design view of PCB
#83=INTERCONNECT_DEFINITION('','interconnect module',#80,#21);
#112=PROPERTY_DEFINITION('','',#83);
#111=PROPERTY_DEFINITION_REPRESENTATION(#112,#105);
#105=GEOMETRICALLY_BOUNDED_2D_WIREFRAME_REPRESENTATION(
'planar projected shape',(#106,#316,#322,#328,#334,#340,#346,#352,#358), #39);
Component Location
#258=NEXT_ASSEMBLY_USAGE_OCCURRENCE('','assembly composition','',#83,#123,$);
#123=COMPONENT_DEFINITION('','interconnect module edge',#80,#15);
#320=PRODUCT_DEFINITION_SHAPE('','',#258);
#321=PROPERTY_DEFINITION_REPRESENTATION(#320,#294);
#294=COMPONENT_LOCATION('planar projected shape',(#295,#285,#316),#39);
#295=DESCRIPTIVE_REPRESENTATION_ITEM('placement fixed','true');
#285=CARTESIAN_TRANSFORMATION_OPERATOR_2D('','','',$,$,#276,1.);
#316=MAPPED_ITEM('component assembly 2d position',#317,#285);
#317=REPRESENTATION_MAP(#192,#189);
#192=AXIS2_PLACEMENT_2D('origin',#193,$);
#189=GEOMETRICALLY_BOUNDED_2D_WIREFRAME_REPRESENTATION(
'planar projected shape',(#192,#364),#39);
#267=SHAPE_DEFINITION_REPRESENTATION(#122,#189);
#122=PRODUCT_DEFINITION_SHAPE('','',#123);
Units
#39=(
GEOMETRIC_REPRESENTATION_CONTEXT(2)
GLOBAL_UNCERTAINTY_ASSIGNED_CONTEXT((#48))
GLOBAL_UNIT_ASSIGNED_CONTEXT((#41,#45))
REPRESENTATION_CONTEXT('',''));
#45=(CONVERSION_BASED_UNIT('mil',#47)LENGTH_UNIT()NAMED_UNIT(#46));
The component_definition has a product_definition_shape that is referenced by an inter_stratum_feature with a description of "interconnect module edge". If the shape is planar it represents a projection of the maximum extent of the Interconnect_module_edge onto the planar shape of the stratum.
The stratum entity
AP210 specifics the individual layers in the PCB AO using stratum entities which may be Design_layer_stratum AO or Documentation_layer_stratum AO or may be Stratum AO. Stratum_feature entities define the shapes in the stratum's material by referencing a product_definition_shape entity that references the stratum. This recommended practice is limited to describing planar stratum.
The Design Layer Stratum
A Design_layer_stratum AO is a type of stratum incorporated into an Interconnect_module for the purpose of realizing a physical network in one material such as signal, power and ground layers. A Design_layer_stratum AO is defined by a stratum entity with a name attribute of "design layer". (This is a major difference from the IS version of the standard.)
The Documentation Layer Stratum
A Documentation_layer_stratum AO is a type of stratum used to describe patterns and other artwork information needed to manufacture a Stratum from materials which are not independently implementing a Physical_network in the PCB AO, such as soldermask, silk screens, and solder paste. A Documentation_layer_stratum AO is defined by a stratum entity with a name attribute of "documentation layer".
The Stratum
A Stratum AO is used where there is no pattern information provided. A typical example is for the partially cured adhesive which reflows during fabrication to fill voids between Stratum_features in other Stratum. A Stratum AO is defined by a stratum entity with a name attribute of "generic stratum".
The Stratum_feature entity
A stratum_feature entity is a subtype of shape_aspect that defines a shape realized in the material of the Stratum. The stratum_feature entity is associated with the stratum by its of_shape attribute that references a product_definition_shape entity whose definition attribute references the stratum entity. The stratum_feature entity is referenced by the definition attribute of a property_definition entity. This property_definition is referenced by the definition attribute of a property_definition_representation entity. This property_definition_representation's used_representation attribute references a shape_representation (Even though the mapping table doesn't require it, the representation for the stratum_feature should be a shape_representation.) entity. The shape_representation defines the shape of the stratum_feature. The shape_representation does not contain any actual geometry, since it is a collector of the geometry from the constituent elements. The shape_representation is usually not populated.
