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I found out that there are differences in the sizes of soldering pads for SMD components depending on the required reliability and available space.

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For resistors (805) I found good sizes (datasheet from Vishay).

Now I'm trying to find sizes for capacitors (805). In datasheets I did not find the size difference depending on the Density level.

Tell me, is there a table where recommended sizes for various SMD components are indicated depending on the density level? Or a special library for Eagle.

Thanks!

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The size of the component terminal is standardised.

It's entirely up to you how much bigger you make the solder pad on the board, but it should be bigger.

There are not 'three different sizes' for the solder pad for an 0805 component (it doesn't matter whether it's a resistor or capacitor). Those three diagrams you have shown are just points on the continuum of sizes from small to big, as suggested by Vishay. More guidance can be got from IEC 61188-5-x.

You want to have sufficient solder fillet to the sides and to the end (toe) of the pad so that you can visually inspect the quality of the joint. Smaller gives you higher density, bigger is easier for beginners to solder.

Note that some manufacturers rate their components' power dissipation when mounted on a particular sized solder pad. This means you have to derate the component if you use a smaller pad.

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  • \$\begingroup\$ Thanks for the answer! Then I will use the same pad (from Vishay) for resistors and capacitors. \$\endgroup\$
    – Delta
    Oct 29 '19 at 14:15
  • \$\begingroup\$ heat removal depends mostly on what TRACE attaches to the solder pads, as well as what PLANES are under the pads and traces. \$\endgroup\$ Oct 29 '19 at 16:55
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When you're talking about the mechanical characteristics of the joints, the nature of the component (resistor vs. capacitor, for example) doesn't make any difference. The same rules apply to both.

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  • \$\begingroup\$ Thanks for the answer! Then I will use the same pad (from Vishay) for resistors and capacitors. \$\endgroup\$
    – Delta
    Oct 29 '19 at 14:14

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