OK, I have been searching all over for this. I am trying to make a footprint in Proteus from an ATtiny841 with the 3mm x 3mm VQFN package. Now I know how to draw foot prints, and I know what a Chamfer is, but the way they describe the Chamfer measurements is what I don't understand. I have attached a picture of the drawing. It will say things like "C0.18 (8X)" for one of them and on the other and another "0.3 Ref (4x)."
For instance what does the 8X and 4x mean? Some kind of magnification? C0.18, does that mean I just take 0.18 and multiply by C? Are they using circles to demonstrate the dimensions with a radius of 0.18? I am so confused by this.
Any help would be GREATLY appreciated. I do embedded software engineering and I have my own projects going on at home so I am trying to learn the hardware side as much as possible. I get a lot of it, but this threw me off a bit.
Thanks again for any help,
Mike Watson
For instance what does the 8X and 4x mean? Some kind of magnification? C0.18, does that mean I just take 0.18 and multiply by C? Are they using circles to demonstrate the dimensions with a radius of 0.18? I am so confused by this.
Any help would be GREATLY appreciated. I do embedded software engineering and I have my own projects going on at home so I am trying to learn the hardware side as much as possible. I get a lot of it, but this threw me off a bit.
Thanks again for any help,
Mike Watson
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