I'm looking for footprint's dimmensions for the standar packages like 0402, 0603, 0805 etc.
I did a quick search on the google and I got many different results and I got confused.
Is there something very common to use both for resistors and MLCC capacitors. I don't want the pads turn out too big or too small.
Answer
Each manufacturer is going to have their own recommendations for land patterns. However, IPC-7351 is a more generic standard that covers SMD component sizes and footprints. There are usually three versions of every footprint: Low density (level A), medium density (level B), and high density (level C) designed for low, medium, and high density boards ("density" referring to how tightly together the components are placed). When I lay out a board, I determine how many components are needed and how tightly packed they will need to be based on the dimensions of the board, and I will pick one density level. I will then use the footprints for that level.
IPC has a land pattern calculator that can help you determine how large or small to make your pads for surface mount components based on the physical dimensions of the component itself (provided by the manufacturer) and the desired density level. The above link will download a ZIP file containing the installation files. If you a tool such as Altium Designer to design your board, it has this calculator built-in and you can generate footprints by entering the component dimensions.
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