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".

e.g. SOIC-8_3.2x5.7mm_P1.27mm

In cases where potential conflicts exist, however, the body dimensions must be explicitly named with the prefix B.

Refer to the table below for accepted prefix abbreviations.

Prefix	Field Description	Notes
B	Body dimensions	Body size (XxYxZ) Height parameter Z may be omitted Prefix B may be omitted if the body size is the major dimension used to define the footprint
D	Diameter	Diameter of major axis for cylindrical component e.g. D10mm - 10mm diameter
H	Height	Height of component measured from PCB Body size B should be used in preference, where possible e.g. H1.1mm - component measures 1.1mm above PCB
L	Length	Length along major axis of component Body size B should be used in preference, where possible e.g. L15.3mm - 15mm length
O	Offset	Offset, where no other name is more appropriate For example, the distance between pads and the body. Affects silkscreen diagram. e.g. O3.81mm - 3.81mm from pads to body.
W	Width	Width along minor axis of component Body size B should be used in preference, where possible e.g. W4.75mm - 4.75mm width
EP	Exposed pad dimensions	Packages that include a single exposed pad include the size of this pad. e.g. EP2.4x3.6mm - for a single 2.4mm x 3.6mm pad.
P	Pad pitch	Pitch (distance) between pins, pads or leads e.g. P0.63mm - 0.63mm pitch between pads
T	Thickness	Component thickness, where appropriate

Examples:

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

Prefix	Field Description
Ball	BGA Ball diameter
Clearance	Clearance between pin rows
Drill	Drill diameter
Layout	Specific footprint layout e.g. Layout3x7 for a BGA with 21 balls arranged in 3 columns and 7 rows
Lead	Lead dimensions
Mask	Custom soldermask dimensions
Pad	Custom pad dimensions
Tab	Tab dimensions