What to name Footprints for PCB Mounted Modules

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I have a need to add a land pattern for a small PCB module that will SM to the board with concave 'pins'.

I have seen this sort of thing before with things like WiFi and power supply modules, and there are through hole versions of some of these also.

In any case, what are these things 'formally' called, and what do folks call the land patterns?

I assume 'XXX_Manufacturer_Part' but I can't think of a nice unambiguous name for an attached PCB module...

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DaveCowl Members Profile Send Private Message Find Members Posts Add to Buddy List Advanced User Joined: 18 Oct 2012 Location: Santa Clara, CA Status: Offline Points: 161	Post Options Post Reply Quote DaveCowl Report Post Thanks(0) Quote Reply Topic: What to name Footprints for PCB Mounted Modules Posted: 16 Nov 2012 at 12:27pm
	I have a need to add a land pattern for a small PCB module that will SM to the board with concave 'pins'. I have seen this sort of thing before with things like WiFi and power supply modules, and there are through hole versions of some of these also. In any case, what are these things 'formally' called, and what do folks call the land patterns? I assume 'XXX_Manufacturer_Part' but I can't think of a nice unambiguous name for an attached PCB module...



Tom H Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Joined: 05 Jan 2012 Location: San Diego, CA Status: Offline Points: 5716	Post Options Post Reply Quote Tom H Report Post Thanks(0) Quote Reply Posted: 16 Nov 2012 at 12:32pm
	The IPC-7351 Footprint Naming Convention has a fundamental format - Component Family + Pin Pitch + P + Body Length X Body Width X Body Height - Pin Qty Example: MOD65P1200X1000X120-6

DaveCowl Members Profile Send Private Message Find Members Posts Add to Buddy List Advanced User Joined: 18 Oct 2012 Location: Santa Clara, CA Status: Offline Points: 161	Post Options Post Reply Quote DaveCowl Report Post Thanks(0) Quote Reply Posted: 16 Nov 2012 at 12:54pm
	I guess 'MOD' would do. Covers a lot of evils. A partially related question - what should one do about parts that want to be placed against or over the edge of the board? This module wants to do that, but the issue also applies to parts like HDMI connectors where the body of the connector hangs over the board edge to fit in a housing slot snugly. I am thinking with respect to courtyard and assembly outline, since I imagine that most CAD tools would highlight a violation for a part extending beyond the board (or even touching the board edge). Is it preferred to reduce the outlines so that no violation is caused, or to keep the outline matching the part and tolerate or flag the violation that results?

Tom H Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Joined: 05 Jan 2012 Location: San Diego, CA Status: Offline Points: 5716	Post Options Post Reply Quote Tom H Report Post Thanks(0) Quote Reply Posted: 16 Nov 2012 at 1:00pm
	All Connector Footprint names are MFR_PartNumber and all connectors should be stored in their own library to isolate them from the electronic packages. MOD is too generic. I would stick to the ComponentFamily_MFR_PartNumber.

AGONZ67 Members Profile Send Private Message Find Members Posts Add to Buddy List Advanced User Joined: 30 Mar 2012 Status: Offline Points: 119	Post Options Post Reply Quote AGONZ67 Report Post Thanks(0) Quote Reply Posted: 26 Nov 2012 at 2:58pm
	In Expedition PCB, the cell editor has an "allow cell overhang" checkbox in the package cell properties dialog box. I am not sure about other layout programs. I keep my outlines around the entire body, and ignore or accept any violations. On a separate thought, under member profiles what about an area to list CAD tools being used, PADS, Expedition, ORCAD, etc?

DaveCowl Members Profile Send Private Message Find Members Posts Add to Buddy List Advanced User Joined: 18 Oct 2012 Location: Santa Clara, CA Status: Offline Points: 161	Post Options Post Reply Quote DaveCowl Report Post Thanks(0) Quote Reply Posted: 26 Nov 2012 at 3:21pm
	Thanks for the note. Certainly some connectors have a dimension that is supposed to be the board edge. I guess that could be worked in to the placement outline too (I believe that Expedition at least allows for more than one polygon in the placement). For the most part I am using Mentor Expedition workflow but hope to widen my scope over time... :)