# Question about dimension on drawing

Hi,
first of all, sorry for posting this question.
I know this is not good question, because this forum is for discussing about Kicad.
but I think here are many people who are good in engineering, so I want to ask about dimesions reading

below picture is drawing about USB c type
I want to use this component and draw footprint
but I have no idea about this red circle, I think this is not meaning 4mm (because if this is 4mm, then it maybe so big)

Could you tell me , what this size is ? and I’m curious about the minus meaning(blue circle)

PS : If this is against rule of forum and If I should delete this post, I’m willing to delete it

My guess is the number before the hyphen (minus) is a quantity. So the red dimension is telling you that 4 of the pads are 0.60 wide. It then follows that 8 pads 0.30 wide, all 12 pads are 1.05 tall, there are 7 0.50 pitch spacings, and the 4 PTH slots have those four dimensions that start with “4-”. Though, the pitch dimension stated like that is redundant because they already have the pad pairs dimensioned relative to the centerline.

I could be wrong, but that is my best guess based on context clues.

Watch the vertical placement of the pads. The top edge of all the pads are referenced from the lower-left PTH slot… They certainly didn’t help you since pads (at least in KiCad) are by default dimensioned from the center. Though I suppose you could define all your pads with a vertical offset of half the vertical pad size so you can match the drawing dimensions without having to do much math…

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You are a genius SembazuruCDE!
I think you give me a exact answer.

Thanks a lot
I have only one curious point, then what is 7 meaning? ( the pitch dimension )
can you guess it ?

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Something else I just noticed. The smallest gap between pins seems to be 0.15mm. Make sure the board house you plan on using can fabricate with copper spacings that small. If the board house specifies in mils that is only 5.9mil spacing. A 6milx6mil fab house might just be able to make this footprint.

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I mentioned that already, but it might be worded poorly. Basically it is saying that 8 pins are at a pitch of 0.50 from each other (7 centerline to centerline dimensions). But since all the other pins are dimensioned horizontally, stating the pitch is redundant.

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I got it, I missed it.

I think Now I can draw this as footprint.

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I’m done, It’s COOL

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Don’t forget to take a look at Rene’s Footprint Tutorial for stuff like Naming conventions, courtyards, first pin and silkscreens.

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thanks der.ule

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