Multiple pins net assigment in library editor

Bug #1530890 reported by Art
This bug affects 12 people
Affects Status Importance Assigned to Milestone

Bug Description

When working with multi-pin components (i.e. LGA and BGA packages) you would quite often to run into a case when multiple pins are connected to the same net (i.e. GND, VCC etc.) Currently the only sensible way to deal with it is to create multiple invisible pins and only one visible and pile them on top of each other so all of them are at the same coordinate, so when you make a connection in the schematics all of them are connected at the same time. This makes editing and modifying the component symbol extremely difficult. If you try to extract a single pin from such a pile at a later time the context menu (right click on the pile) would only give you "first" 10 pins (not even the first 10, but just 10 pins in no discernible order). The best solution would be to have a tool like the Wire Tool in the schematic editor available in the library editor so you could create multiple connection between pins which would correspond to the internal pin connections of the part.

Tags: eeschema
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Chris Pavlina (pavlina-chris) wrote :

Unrelated to your suggestion, but just a remark: stacking invisible pins on top is a very bad idea, as depending on the parameters of the pin, they may be subject to automatic connection by net name. If you're going to do that (I do, sometimes, in my own libraries), stack multiple visible pins, and hide the text by setting its size to zero.

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Dave Vandenbout (devb) wrote :

I would like this feature, but I would prefer to enter a list of pin numbers where it currently allows only a single pin number.

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Art (diametrix) wrote :

I could get behind this solution as well

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Art (diametrix) wrote :

One more relevant thing that I noticed. If you try to use approach of invisible pins (or visible for that matter) and pile them up on top of each other and that happens to to be pins with no connection, there will be a DRC error generated: "A no connect symbol is connected to more than 1 pin. This would need to be considered if the feature discussed about is implemented because a NC pins are very common.

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Sebastian Kaminski (seeebek) wrote :

A very prominent example of this missing feature is the simple push button with 4 pins. The pairs of pins are internally connected creating a jumper of sort. Physically it is not important which pin you connect but in Kicad you have to change the footprint for every case you need.
Other very common usage where this feature is needed is when creating components which are boards like e.g. Arduino. Where there are multiple GND pins fully connected with each other. Or even my latest problem: the Adafruit 16-Channel 12-bit PWM/Servo Driver based on PCA9685. There are pairs of GND, VCC and V+ "pins" fully internally connected without any constraints as to resistance or inductance. Using those can drastically simplify routing when using one of those boards as a shield.
I hope this examples will help to understand why this feature is very needed in Kicad.

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Novak Tamas (novak-7) wrote :

For large packages with lots of VDD and VSS pins, I make 2 units, where "all units are not interchangable". "A" part has the important pins, and "B" part is for the power. See schematic attached for an LQFP176 package STM32F429 MCU.

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Dio Brando (dio.brando) wrote :

I prefer Dave solution too (#2), respect to add all the pins with the same function to the symbol then connect them together to the scheme. It helps to reduce symbol required space and to simplified the symbol creation without using escamotages like hiddens pins.

Jeff Young (jeyjey)
Changed in kicad:
importance: Undecided → Wishlist
status: New → Triaged
tags: added: eeschema
Revision history for this message
KiCad Janitor (kicad-janitor) wrote :

KiCad bug tracker has moved to Gitlab. This report is now available here:

Changed in kicad:
status: Triaged → Expired
Changed in kicad:
importance: Wishlist → Unknown
status: Expired → New
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