F2.2 Footprint naming field prefixes
A footprint name has to convey a lot of information to clearly specify the purpose and parameters of the footprint. Some fields in footprint names are common to many footprints and can be shortened using special abbreviations.
Not all footprints will require the use of these abbreviations - they are provided as a method of standardising the manner in which footprint parameters are called out when encountered.
In many cases, the major dimensions (x/y/z) of a footprint may be specified without a prefix, as the body dimensions are assumed to have the greatest priority in the footprint name. Therefore, the "3.2x5.7mm" part of the example name below requires no 'B' prefix, and is not required to be written as "B3.2x5.7mm".
In cases where potential conflicts exist, however, the body dimensions must be explicitly named with the prefix
Refer to the table below for accepted prefix abbreviations.
|Exposed pad dimensions
|Component thickness, where appropriate
LQFP-32_4x4x1.1mm_P1.65mm- LQFP package, 32 pins, 4x4mm body, 1.1mm height, 1.65mm pitch
CP_Radial_D4.5mm_P2.5mm_H10mm- Radial polarized capacitor, 4.5mm diameter, 2.5mm pitch, 10mm height
If the parameter is not found in the table above, the name of the parameter should be entered in full.
Following is a list of examples of (non-abbreviated) parameter names used in footprint naming
|BGA Ball diameter
|Clearance between pin rows
|Specific footprint layout
Layout3x7 for a BGA with 21 balls arranged in 3 columns and 7 rows
|Custom soldermask dimensions
|Custom pad dimensions