I have a project with only one component: PTZ3904 from standard library.
When I export the schematic to PCB I get the error:
Q1 pad 4 not found in Package_TO_SOT_SMD:SOT-223-3_TabPin2.
Design Rules Checker from PCB Editor does not give any error.
Everything seems ok, but that error during load/update is an annoying.
I saw a similar topic un november 22, and it seems not solved.
I think you mean PZT3904. This is a 3904 in a SOT-223 package and has 3 pin numbers in KiCad’s library.
This is a footprint that looks like this:
which also has 3 pad numbers and should match. So it seems your symbol has a pin number 4. Where did it come from?
In some datasheets on the Internet, like this one: https://www.onsemi.com/pdf/datasheet/pzt3904t1-d.pdf the tab is numbered 4, but is the same connection as 2. Such a symbol should not be used with the 3 pad number footprint above.
For SOT223 there are 2 logical solutions:
- use symbol having 4 pins and footprint having pads 1,2,3,4,
- use symbol having 3 pins and footprint having pads 1,2,3,2.
It looks that you have symbol from 1 solution and footprint from second.
As connection from schematic is not mapped to PCB connections to be done and then not made at PCB then at PCB everything is in order.
I think (don’t have KiCad here) in DRC there is a checkbox to check during DRC compatibility between schematic and PCB. If it will be checked than I expect you will get some error in DRC.
YOU RIGHT!
Changing the footprint to “SOT-223” solved the problem.
Then it seems that component PZT3904 needs to be fixed in official library as I used it --as is–, never minding that its footprints had this problem.
BTW compatibility was ok also before check of corrispondence.
You think I should inform anyone?
YOY RIGHT. See answer to Piotr.
I don’t see anything wrong with the symbol or the linked-to footprint. The symbol has pins 1-3 in the standard KiCad library on my 8.0.4 installation; it has no pin 4.
Maybe you got it from a symbol library with an older version that had pins 1-4 and it was fixed after you added the symbol. You didn’t state what KiCad version you’re using.
Using 8.0.3. OK, I will update. TNX.
It is not related to your question directly but KiCad releases with number X.0.1 and X.0.2 are typically very buggy (X.0.3 less but still). For each last number update several dozen bugs are fixed so it is good idea to update when last number changes.
After 8.0.6 was released I reported a bug that was fixed in less than 2 hours (8.0.7 will be free from this bug).
Whenever you want to speak about bugs you should first update to last stable release as may be a bug was already found and fixed.
However as KiCad now stores the symbol and the footprint in their respective files, you won’t get the updates unless you choose to Update from Library. Since you’ve already placed a 4 pin number symbol and 4 pad number footprint into the project maybe just leave well enough alone.
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