VSSOP / TSSOP ambiguity


#1

Hi,

According to Ti the INA2180 is an 8 pin VSSOP (*0.65 pitch, 3mm^2). However in Kicad the VSSOP is 0.5 pitch and a different dimension. The one that appears to fit is:

Housings_SSOP:TSSOP-8_3x3mm_Pitch0.65mm

https://www.ti.com/general/docs/lit/getliterature.tsp?baseLiteratureNumber=sbos741&fileType=pdf

How to verify this is correct?

Andrew


How to check footprint correctness?
#2

By checking all dimensions of the footprint against the datasheet values.

I found freecad + kicad-stepup + drawing dimensions is a good tool for this task.
(The newest version of stepup is only available via the freecad 0.17 addon manager)

This allows you to create similar drawings then i did in this pull request comment: https://github.com/KiCad/kicad-footprints/pull/60#issuecomment-345468460

Here a sketch of the footprint compared to the maximum pin dimensions: (I know i should have used some sort of statistical calculations to get the “true” toe, heel and side measurements.)


#3

@snoopy20 manufacturers love having very slight variances between footprints and naming them different things.

For this reason, aside from the “generic” footprints like the one you linked above, we have provision for manufacturer specific ones.

Here’s an example of a Texas Instruments footprint from that library - https://github.com/KiCad/kicad-footprints/blob/master/Package_SSOP.pretty/Texas_R-PDSO-N5.kicad_mod

The S-PDSO-G8 footprint doesn’t currently exist in the KiCad libraries but you can contribute it very easily :slight_smile: Then other users can make use of it also!