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Thermal Relief doesn't work for Power palnes

Hossein1357

Hi,

I have defined circle as Thermal Relief for all layers of my pads. Below are some questions regarding shape drawing in various layaers:

1- Thermal Relief doesn't work for power planes while it works for signal, Top & Bottom Layers. I see that it only uses a zero length cross to connect pad to polygone or shape in power planes (Figure 1)

Figure1

drive.google.com/.../edit

2- Shape in power planes is connected to pins of other nets!.(Figure 2)

Figure2

drive.google.com/.../edit

3- After changing constraints shapes or polygones seem to be connected directly to pads!. How can I make sure that all constraints are applied after any shape or constraint edit (Figure 3)

Figure3

drive.google.com/.../edit

4- Where can I change settings for thermal pads? I mean "connect width" and "gap" between plane and pad (Figure 4)

Figure4

drive.google.com/.../edit

5- Do I have to use Shape-> Check for all shapes or polygones everytime I make changes in Constraint Manager or there is a much easier way for it?

I am very short of time. So, I need urgent help.

Thanks all in advance,

Hossein

  • oldmouldy

    You mave a "min_line_width" of 0.

    If you change the rules, you will need to update the shapes, since this might take a while for some designs, shapes are not "just updated", use Display>Status. or Shape>Global Dynamic Parameters, and "Update to Smooth", or "Force Update" in GDPs, if required.

    Thermal Spoke Width  uses min_line_width in Constratint Manager from the Physical domain, add / override that from Shape>Global Dynamic Parameters, Thermal Reliefs. Pad to Shape spacing is controlled from "Pad to Shape" in Same Net Spacing, also enable all the Same Net checks in Analyze>Analysis Modes.

  • Hossein1357

    Thank you for your answer. Unfortunately, I still have some problems:

    1- If I define plane outline shape, it'll be always "Solid " not connected to pad, I need to change it to Dynamic copper. Below link shows it:

     https://drive.google.com/file/d/0BzS3_lT7y4tEaUI0MW4wRkxkZVk/edit?usp=sharing

    2- Even after changing shape to Dynamic copper it is still connected with 0 width to pad. Although I have defined other value for min line width. Furthermore, it connects to the pad with correct width when I draw it in Top, Sig or Bottom Layers. Only Power planes!.

     https://drive.google.com/file/d/0BzS3_lT7y4tEWVpwckJoLUg3YU0/edit?usp=sharing

     Thanks in advance,

    Hossein

  • chads108

    Are your planes defined as positive or negative in the stack-up?

    Chad

  • Hossein1357

    I don't see why shape clearance doesn't affect pins inside the shape?!. Below picture shows that just one of shapes of power plane is affected by shape clearance?!

     

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