Altium error component clearance constraint... - Page 1
Forum section: electronics / general

author: Dandelion9
author_rank: Newbie
timestamp: January 26, 2015, 06:16:03 pm
content: Hello, I am a student and I wanted to draw this pcb where led display goes above max7219:http://embedded-lab.com/blog/wp-content/uploads/2012/05/SPI7SEG_4Digv1.0KIT.jpghttp://embedded-lab.com/blog/wp-content/uploads/2012/05/SPI7SEG_4Digv1.0Board.jpgBut, I am beginner in Altium and I have no one to ask what rule I have to change to make this possible. I get an error: "component clearance constraint between component on bottom layer and component on bottom layer" when led and max are in bottom layer. I am sure that the answer is probably simple, but there are so many options in Altium and I have never designed pcb before.Thank you in advance!

author: toohec
author_rank: Contributor
timestamp: January 27, 2015, 02:15:39 am
content: The component clearances are verified/checked based upon the 3D-Body information embedded in the footprint of the components. I'm going to guess that your footprints are either missing their 3D bodies, or the 3D bodies do not accurately represent the component or your intended mounting style of said component. For instance, the 3D body of the display component may be drawn with the display flush against the board surface, versus raised off of the board to accommodate components placed underneath the display. You would need to create a new display footprint with the appropriate raised 3D body in this case. Once you have the correct 3D body information in place, the acceptable component clearance is defined in the Design Rules, under thePlacement > Component Clearancerule set.Note that in the case where the 3D body information is missing from the footprint, the component's size is defined as the smallest rectangle that contains all of the primitives on the silk and copper layers (excluding the designator). The height is defined by the height value specified in the component properties. This method is very limited and will not accommodate cases with vertically overlapping components, so I suggest creating 3D bodies for proper clearance checks in this case.In the layout tool, you can press "3" on the keyboard to view the PCB in 3D mode and review the 3D bodies of the components currently on the board. You should be able to see which parts require changes to their 3D bodies, or if any components are missing them completely. (Press "2" to return to 2D view.)If you need to modify/create a 3D body, you can reference the following Altium tech doc...http://techdocs.altium.com/display/ADRR/PCB_Obj-3DBody((3D+Body))_ADGood luck. Let me know if you need any further clarification.

author: Dandelion9
author_rank: Newbie
timestamp: January 28, 2015, 04:30:48 pm
content: Yes, I don't have the 3D body of the display component, so I am going to draw it or find a display with 3D body.Thank you very much!

author: gxti
author_rank: Frequent Contributor
timestamp: January 28, 2015, 06:40:49 pm
content: It doesn't need to be a fancy STEP model, you can do it with basic "extruded" boxes. A very simple model you could make is a single box stood-off from the PCB by a few millimeters.That said, this type of LED module is very common and you won't have much trouble finding an existing STEP model you can drop in. 3dcontentcentral is a good place to search, although you have to sign up for a free account to download anything. You will probably still need to tweak the standoff distance to get it to clear your parts.

author: Dandelion9
author_rank: Newbie
timestamp: January 28, 2015, 06:51:51 pm
content: I did it with Place->3D Body extruded model type.Thank you for the 3dcontentcentral, looks like it's going to be useful.