SMD components foot print and selection

Hi so i am new to kicad. Now i want to use standard 1206 package smd resistor. now when i open assign footprints i only have two options for smd resistor 1206. Both are the same except one is hand soldered and the other isnt.

Now as i am going to hand solder the component i selected hand solder option. Now when i go into PCB mode in kicad and import netlist. I then checked the dimensions of the smd resistor i see the dimensions are 4.915X2.273 mm

However if you see the standards the dimension for 1206 SMD resistor is 3.2X1.6 mm with a tolerance of 0.1 in length and 0.15 mm in width.

Hence why is this difference . Should’nt the component footprint in kicad be the normal standard value.

Further please clarify how to select a smd tantalum capacitor with dimension given below. Please note my capacitor has a case code H in the table (last line in the table in figure.

It is not clear why such standard components are not available in the library .

How do you get to this dimension for the footprint?

You’re looking at the courtyard dimensions, not the package dimensions. In fact, the package dimension is not indicated in the footprint, apart from the 3d model, and the name of the footprint.

The F.Fab outline has the nominal body size.

So it does - didn’t have that layer turned on :smiley:

And the courtyard size for any 5.x footprint can (or should*) also not have the dimensions reported by the user as the courtyard outline must be rounded to 0.01mm grid. For 4.x footprints the rounding should be for 0.05mm grid meaning even more unlikely that it is the courtyard dimension unless the footprint is so old that it still violated even these basic KLC rules.

*) i am sure there are non complient footprints in the lib. I am however certain that the footprints for two terminal passives followed KLC for the full version 5 cycle as they are script generated (using the rules of the KLC and IPC-7351B)

There might be something suitable in Capaitor_Tanatulum_SMD, eg CP_EIA-3528-15_AVX-H

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hi so here is a pic of how i measured the resistor foot print

So now that i have the F.Fab layer on i am measuring the actual footprint. Hence can anyone tell me why there is the error

In the screenshot you measure the courtyard layer. The fab layer is also gray in the default kicad colour scheme which might be the source of your confusion.

Additionally you seem to have a quite old footprint here. The current versions have rounded rectangle pads as per new IPC suggestions (IPC-7351C which is overdue will codify this) Is it possible that you have the version 4 footprint? (all version 5 footprints have rounded rectangle pads, i just double checked the ones from 5.0.0) After checking the screenshot again it looks like you have a footprint with rounded rectangle pads. It is just too little resolution to show this clearly.

You also seem to be on at best version 5.0 as the footprint editor would have a treeview in version 5.1.x Sorry for the confusion you are in pcbnew.

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Turn off all the layers except the F.Fab, there are several grey layers…

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okay now got how to measure the components thanks . But still not able to find a berg strip connector. Please help


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hi i am using an LM7805 5V regulator with a TO-220package. Now i will be mount it vertically . That is just imagine the pcb is placed at the bottom of the image and the component is mounted straight through. Now which To220 package do i choose for the foot print there are many like 220-2 then 220-3 etc .Then the is is verticle and horizontal.

Please help

Well look at both packages it will become quite obvious which one will fit (either in the footprint editor or in one of the review options when assigning See How can i assign a footprint to a symbol?).

I think you want TO-220-3_Vertical.

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Man you take all the fun out of it.


It was my New Year resolution.

Man it’s the third of January, a bit more dedication please!
:joy: @Rene_Poschl @bobc

hey i need to use the SMD variant of the CD4017 IC. Now when i am assigning footprint it automatically gives me a selection of the 16 pin DIP Package (see pic below). However none of the footprints match the datasheet. all the footprints have the length of IC as 20mm but as per datasheet it is 10 mm. See fig below. where do i get the footprint