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This TechWatch is based on 3rd part of the Altium Designer presentation performed at our UK User Conference on the 6th Sept 2005

In this Final part we look at the use of Placement Rooms for floor planning, design rules and multi-channel designs. We will also look at the use of Component Bodies on footprints for clearances and 3D view of your PCB.

For the purpose of this TechWatch I have made the files I used available here Download, most of files are based on standard Examples available with Altium Designer 2004.

Placement Rooms

For this TechWatch we will be using the Mixer.PrjPCB from the files I have made available to Download.

By default when synchronising your Schematics with your PCB Protel will generate a Component Placement Room for each of schematic sheets in your hierarchy.

As we can see looking at the Multi-Channel Mixer project it will also generate a placement room for each of the channels in the design, which are logical rather than physical schematics.

If we take a look at the project options dialog box we can see the Class Generation setup, open the Mixer.schdoc and then go to Project » Project Options » Class Generation.

On the PCB side we can see the way that the Rooms have been imported and the components placed within the rooms ready for us to do a little floor planning.

Open the Mixer_Loaded.PcbDoc. If we move the rooms around the components will move with the room, if we want to move the room without moving the components we can use the Define option within the rooms properties.

Double click on the COUT1 room and click Define, from the properties dialog box, then draw the new position of the room bottom Right of the board.

Tools » Component Placement » Arrange within Room will then allow you place the components back inside the room ready for placement using the usual placement commands.

We can then place our rooms.Since this is a Multi Channel room we only have to place and route this one room and we can then use the Copy Room formats to make the other channels identical.

Place some of the components in COUT1 and then move COUT2 down by clicking and dragging the room or using Design » Rooms » Move Room and then use Design » Rooms » Copy Room Formats. Select COUT1 and then COUT2 which will then open the Confirm Channel Formats Copy dialog for you which you can setup as show to copy placement and room size.

Once you have placed your components it does not necessarily mean that the rooms are of no use. They can be used, for example, to create design rules for a region.

For example we could assign an area of the board with a height restriction or lets make an area of our board have a direct connect to an internal plane.

Open the Mixer_Routed.PcbDoc and zoom in on C47 and then go to Design » Rules and add a new rule for Power Plane Connect Style set the rule to Direct Connect. The rule query is WithinRoom

Component Bodies

Lets look some more at component bodies. As shown earlier with a BGA component we can place the component bodies using primitives from any layer of the component and can also be drawn manually on a Mechanical Layer.

Using these component bodies not only can we now use them to define whichever horizontal clearance we want for our components we can also use them for vertical clearance.

Sometimes you might have components that overlap each other or smaller components underneath larger components on the same layer.

If we take a look at a version of the mixer board where I have added some placement rooms and moved a couple of components underneath the Transformer we can see this.

Open the Mixer_3D.PcbDoc. Go to T1 where there is a design rule violation.

Right Click on the violation and see that there is a Component Clearance error.

If we look at the component bodies for these two components we can see that the transformer has a Standoff Height of 5mm and the Diode has a height of 5mm.

Right Click on T1 and go to Component Actions » Manager Component Bodies for Current Footprint. And the same for D5.

Looking at the design rules, Design » Rules – Component Clearance - Transformer Rule. we have specified a 2mm Vertical clearance, so lets change the standoff height of the transformer.

Close the design rules and Right Click on the T1 and go to Component Actions » Manager Component Bodies for Current Footprint and change the Standoff Height to 7mm

Run DRC and the errors will clear.

3D Component Bodies

We can also use these new component bodies to create 3D shapes for our components which can be viewed in the inbuilt 3D viewer.

I’ve added some components bodies to a few more component bodies on the Mixer_3D.PcbDoc board. If we look at the Pots we can see that I have defined 2 component bodies with different height information.

Right Click on a POT and using Component Actions » Manager Component Bodies for Current Footprint you can see the two component bodies with different height information.

As you see quite a smart way to define the 3D shape for components if can’t get hold of a 3D model for it.