There are many different types of surface mount packages used in electronic circuits. When anew surface mount package is developed, an new name is created, names usually abbreviated by their initials.
Usually these components have a code an name standardized by JEDEC (Joint Electron Device Engineering Council) Solid State Technology Association .
In this article will just explain the dimension and code of package used for Flat Chip devices like resistors and capacitors.
For the Flat chip package the code is formed from 4 digits .
The first two digits refer to the length (L) from termination to termination, and the second two digits refer to the width (W) of the termination.
Is very important to know that the size of the component can measured in inches or metric units.
For example, if the first two digits in the size code are 10, then the length of the flat chip is 0.10". However, if the size code is metric, the 10 would equal 1.0mm.
Bellow you can see sizes and codes used for SMD resistors and capacitors.
MELF stands for Metal Electrode Face Bonded and consists of two terminals bonded into a cylindrical body . MELF package are most used for resistors and diodes.
The E.I.A. and I.E.C.Q. organizations have established four standard case sizes for the MOLDED TANTALUM CAPACITORS. These case sizes are designated with the letters A, B, C, D or by their 4 digit metric size code.