User Guide

8.9 ComponentsontheSolderSide
SMD components (and leaded ones too) can be placed on the top or
bottom layers of a board. For this reason EAGLE makes a set of prede
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fined layers available which are related to the top side (To p , tPlace, tOri
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gins, tNames, tValues etc.) and another set of layers related to the
bottomside(Bottom, bPlace etc.).
SMD components are always defined in the layers associated with the
top.
In the board, a component of this sort is moved to the opposite side
with the MIRROR command. Therfore click the component with the
mouse or enter the component's name in the command line. This causes
objects in the To p layer to be reflected into the Bottom layer, while all
the elements in the t.. layers are reflected into the corresponding b..
layers.
If one of the commands ADD, COPY, MOVE, or PASTE is active the
componentcanbemirroredbyclickingthemiddlemousebutton.
8.10 CreatingNew Package Variants
Most components are manufacured in various package variants. Sup
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posed you do not find the appropriate package for a certain device in
oneofthelibraries,itisveryeasytodefineanewpackage.
To describe this procedure clearly we want to come back again to our
exampledevice 541032A fromparagraph8.2.
Please notify the explanations concerning this topic, in particular if the
appropriate package already exists in the current library beginning with
page 184.
The third package variant to be designed here only serves as an example
forpracticeanddoesnotmeetthespecificationsofthemanufacturer!
PackagefromAnotherLibrary
In the most favorable case you can use an already existing package from
another library. The easiest way to define the new package variant is to
usethePACKAGEcommanddirectlyintheDeviceEditor.
After searching all libraries, either in the Libraries branch of the tree
view in the Control Panel or with the help of the search function of the
ADD command in the Layout Editor (only there, not in the Schematic,
one can search for packages), it is possible to Drag&Drop the package
from the Control Panel directly into the library. As an alternative you
couldusethePACKAGEcommand.
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ComponentDesignExplainedthroughExamples