1
$\begingroup$

I'm trying to create a PCB footprint for this part, but I'm not familiar enough with dimensioning to fully understand the diagram.

Usually dimensions like D and E are specified as minimum and maximum values, but here they are using the profile dimensioning. I thought I could understand it by learning a bit of GD&T but I'm still confused by the reference the C datum and what that means.

Would the maximum dimension of D be 8 + 2 * (1/2 * 0.15)? What would the C mean in that case?

Datasheet page

$\endgroup$
2
  • $\begingroup$ I do not know this notation, so I can merely guess. IMHO A, B and C with filled triangles denote the coordinates (as X,Y,Z). These are referenced in the more complex dimensioning boxes (e.g. //|0.20|C). Not to be confused with the length "A". $\endgroup$
    – Ariser
    Dec 6, 2022 at 1:45
  • $\begingroup$ D is given as 8.00 mm BSC. BSC makes more sense with the ball distances, but for the outer dimensions you could think of it as the distance between the centers of two parts touching each other. There's no 2*(0.5 + 0.15) because that denotes something different (I think you confused the length A with the coordinate A). The 0.15 are IMHO the maximum warping of that edge in C-direction. $\endgroup$
    – Ariser
    Dec 6, 2022 at 1:57

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.