Shorted Pins

Making PCB Layouts, Manual routing, Auto-routing, Copper pouring, Updating from Schematic, Manufacturing Output
Post Reply
Message
Author
matttay
Posts: 47
Joined: 08 Aug 2010, 01:58

Shorted Pins

#1 Post by matttay » 07 Jun 2021, 12:49

This has been discussed over the last 10 years on the forum, but it doesn't seem there's a good solution.

There's a need to allow pins to be shorted in a footprint such that it does NOT cause an error in a board. A common situation is using a shorting resistor to isolate two nets. This allows you to determine the location where the shorting will occur. During development, it's easy to cut and insert a real resistor to measure current if needed. But the part never has to be actually placed during production, because it's shorted.

Some solutions on the forum include the same net name on the left/right side of the resistor. But that breaks the intent of isolating the two nets. Others just say "live with the errors", but as you can see in the attached, a single shorted part results in 8 errors, and 30 of these shorted resistors in a board means a lot of errors to sort through.

Diptrace folks, what is your recommended approach for this commonly used technique?
diptrace_error.png
You do not have the required permissions to view the files attached to this post.

Tomg
Expert
Posts: 1747
Joined: 20 Jun 2015, 14:39

Re: Shorted Pins

#2 Post by Tomg » 07 Jun 2021, 16:42

It would be helpful to have the ability to right-click on an error in the error report and enable/disable an option called something like "[x]Ignore" in the pop-up context menu. If "[x]Ignore" is enabled by the user, that particular error text should then turn a different color (or perhaps be grayed out) to remain as a warning and the error flag in the Design Area should disappear. Unfortunately, I don't see DipTrace implementing a feature like that anytime soon. It would be nice to be pleasantly surprised, though.

There is a clunky way to minimize the number of errors in this situation, but not all of them of course. If you are interested, here's one way to do it...
1) Place the empty component on the PCB.
2) Route one L-shaped trace from each pad to separate locations and terminate each using the [Enter] key.
3) Slide one of the L-shaped traces (e.g. the bottom trace) to the center point between the two pads.
4) Slide the remaining L-shaped trace (e.g. the top trace) to the center point between the two pads such that it overlaps the end of the other trace.
5) Hopefully, this should result in only one annoying error flag with its accompanying text in the error report.
sj1.png
You do not have the required permissions to view the files attached to this post.
Tom

matttay
Posts: 47
Joined: 08 Aug 2010, 01:58

Re: Shorted Pins

#3 Post by matttay » 07 Jun 2021, 20:02

Hi Tomg, yes, that is better but then you get a check net connectivity error. I like your idea of an "ignore" for each error, because that lets you demote the errors during development, and then just before release you could un-demote all the errors and then go through a final check to make sure the intent is understood on errors.

Post Reply