SOT343R

Started by Jason, January 05, 2014, 08:26:36 PM

Previous topic - Next topic

Jason

SOT343R has one leg which is wider than it is long, unlike
the other three.

It is a "gull" type and the CDF editor always seems to apply
the "footprint length" attribute to whichever of the X and
Y size is the greater. This means that the bend in the gull
is always in the wrong orientation for this very wide leg.

I'm guessing I'm going to have a similar issue with other
components which have a "tab". I notice the supplied
library part for SOT89 doesn't use "gull" type, probably
for exactly the same reason.

Anyone got any work-arounds other than use a "simple"
leg type?
How will this affect the imager? Do I need to just describe
the flat part of the tab that will be in contact with the
board?

phonoplug

Hi - I've come across this with SOT143.

The solution is to have two leads right next to each other so that each of the two is narrower than it is long. The system doesn't care that you have two leads when there is only one pad on the PCB, or that it will only see one when visioning. Works fine.

Will attach a picture if I can...

phonoplug

By the way, technically thats an SOT-143R (reversed SOT-143), but I only found that out after I'd been placing it for ages, and I have not had to place a non-reversed one so never corrected it as its an ar5e to go through all the BOMs, transfer files and jobs. Pah.

Jason

"Ideal" solution, many thanks!