The SMD command is used to add pads for surface mount devices to a package. When the SMD command is active, an smd symbol is attached to the cursor. Pressing the left mouse button places an smd pad at the current position. Entering numbers changes the x- and y-width of the smd pad, which can be up to 0.51602 inch (13.1 mm). These parameters remain as defaults for succeeding SMD commands and can be changed with the CHANGE command. Pressing the center mouse button changes the layer onto which the smd pad will be drawn.
The orientation (see description in ADD) may be any angle in the range R0...R359.9. The S and M flags can't be used here.
The roundness has to be entered as an integer number between 0 and 100, with a negative sign to distinguish it from the width parameters. A value of 0 results in fully rectangular smds, while a value of 100 makes the corners of the smd fully round. The command
SMD 50 50 -100 '1' *for example would create a completely round smd named '1' at the given mouseclick position. This can be used to create BGA (Ball Grid Array) pads.
SMD names are generated automatically and may be modified with the NAME command. Names may be included in the SMD command if enclosed in single quotes.
The following flags can be used to control the appearance of an smd:
|NOSTOP||don't generate solder stop mask|
|NOTHERMALS||don't generate thermals|
|NOCREAM||don't generate cream mask|
By default an smd automatically generates solder stop mask, cream mask and thermals as necessary.
However, in special cases it may be desirable to have particular smds not do this.
The above NO... flags can be used to suppress these features.
A newly started SMD command resets all flags to their defaults. Once a flag is given in the command line, it applies to all following smds placed within this SMD command.
Single smd pads in boards can only be used by defining a package with one smd.
It is not possible to add or delete smds in packages which are already used by a device, because this would change the pin/smd allocation defined with the CONNECT command.
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