torocar
10-22-2006, 04:14 PM
Hi all. I know this is not the intended use for this forum... but I have really exausted all the other possibilities I know (I posted this question in edaboard's forum and even in orcad community's forum). Besides if a microcontroller product makes it into the PC board stage I'm sure this question might be useful for other users.
Any way here it goes. A component of my design requires me to create a footprint of an irregular shape (see image attached).
I have read a few tutorials from this site (and from other sites) such as ELEC 424, so plz don't redirect me to those.
1. Suppose the blue sprayed landpattern is defined by means of padstack. The Layout padstacks cannot be "T" shaped (such as the one I need). How can I add the RED sprayed areas to the footprint?
2. Should I use a copper area obstacle in the same layer than the copper of the padstack?.
3. How to implement a solder resist area for the red sprayed land pattern section? (I'm not talking about the padstack does a copper area in the SMTOP layer do the job? (I'm kind of confused because the obstacle is called copper area but the physical material wont be copper... actually it would be an area unconvered by solder resist material).
4. How can I force OrCAD Layout to attach the traces to the area sprayed in red instead of the area sprayed in blue? (what I want to do is to thermal isolate the component to be soldered there, so I need the traces or copper pours only attach to the external tips of the footprint)
Thanks a lot for your attention.
BTW: I'm using OrCAD Layout v9.1 but I'm sure the theory involved to create this footprint can be the same if taken from a newer version.
Any way here it goes. A component of my design requires me to create a footprint of an irregular shape (see image attached).
I have read a few tutorials from this site (and from other sites) such as ELEC 424, so plz don't redirect me to those.
1. Suppose the blue sprayed landpattern is defined by means of padstack. The Layout padstacks cannot be "T" shaped (such as the one I need). How can I add the RED sprayed areas to the footprint?
2. Should I use a copper area obstacle in the same layer than the copper of the padstack?.
3. How to implement a solder resist area for the red sprayed land pattern section? (I'm not talking about the padstack does a copper area in the SMTOP layer do the job? (I'm kind of confused because the obstacle is called copper area but the physical material wont be copper... actually it would be an area unconvered by solder resist material).
4. How can I force OrCAD Layout to attach the traces to the area sprayed in red instead of the area sprayed in blue? (what I want to do is to thermal isolate the component to be soldered there, so I need the traces or copper pours only attach to the external tips of the footprint)
Thanks a lot for your attention.
BTW: I'm using OrCAD Layout v9.1 but I'm sure the theory involved to create this footprint can be the same if taken from a newer version.