Hi, First of all, sorry for opening a new thread but I've just subscribed and have no idea how to reply to an email I hadn't received.
A couple of days ago I submitted two changes to the library and footprints: a) Added some MOSFETs with the mounting tab present in the form of fourth pin: https://github.com/KiCad/kicad-library/pull/76 b) Added TO-220 horizontal footprint with a pad and mounting hole for the tab, both marked as pin 4: https://github.com/KiCad/Transistors_TO-220.pretty/pull/1 There were several reasons to choose such approach for my proposal. I've considered the following things: 1. The designer will have freedom of choice whether to connect the tab electrically or not, as it is represented by a separate pin (in case of these MOSFETs it is drain, labelled D_tab). 2. In case the tab is connected to anything else than the middle pin, the footprint is still useful. (Sincerely, I don't know if any component like that exists.) 2. The pad in the footprint may serve as either connection or clearance on both copper layers. I hope this approach doesn't break anything. I might, however, be too complex solution to a simple thing, especially if tab is never connected to anything else than pin 2. The only issue I've noticed so far is that using my 4-pin MOSFET components with a 3-pin footprint (any vertical one, for example) makes Pcbnew complain about missing pins. Regards, -- Michał Sałaban -- Mailing list: https://launchpad.net/~kicad-lib-committers Post to : [email protected] Unsubscribe : https://launchpad.net/~kicad-lib-committers More help : https://help.launchpad.net/ListHelp
