National Instruments Graphical User Interface Ultiboard, Руководство пользователя

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Chapter 1 User Interface
NI Ultiboard User Manual 1-24 ni.com
The Capture Land Diameter field determines the land diameter where the
microvia starts, while Target Land Diameter determines the diameter
where the microvia ends. These terms are in accordance with the IPC and
JPCA joint standard IPC/JPCA-2315, Design Guide for High Density
Interconnects (HDI) and Microvias. The
Maximum Layer Span is either
one or two layers.
Maximum Vias Per Net
The Nets area is where you set up the maximum number of vias allowed
per net.
Surface Mount Pads Oversize
Depending on the manufacturing process you are using, you may wish to
enlarge the size of all surface mount pads by a fixed amount. This can be
set independently for the
Top and Bottom layers. The setting refers to the
amount that will be added to the pad. In the case of a circular pad this
amount is added to the radius. In the case of a rectangular or square pad the
amount will be added to the width and length.
General Layers Tab
Use the General Layers tab of the PCB Properties dialog box to control
which layers are available on the board.
Complete the following steps to control the numbers of layers in the board:
1. Add layers to the board by selecting the checkbox beside the layer
name.
2. Remove layers from the board by clearing the checkbox beside the
layer name.
Note You can have a layer available on the board, and temporarily dim or hide it. Refer to
the Accessing Layers section of Chapter 3, Setting Up a Design , for more information.
Note There are up to ten mechanical CAD layers in PCB design. These layers allow you
to provide information that is directly related to the PCB. You place elements on them to
represent the mechanical elements of your design – for example, cabinet casing or
mounting brackets.