![]() | In this lesson you'll create che schematic component called CN1.
So, you'll be able to add the CONN1 component into the TUTOR1.SCH
electric scheme.
The component will be linked with MP5 pcb component,
that is part of the standard library file PCB.LIB of Circad.
The component CONN1 must be created into a library containing schematic
component, so isn't possible to use the COMP_PCB.LIB library file, in which are been
stored the pcb component MIOTRAN. Then you must create a new library file
containing schematic components with
To create the component you need to follow the same steps of the MIOTRAN component creation. In case of schematic component the elements (shape, pads, etc.) placing is not so critical like for pcb component. In fact, the pcb component shape must be equal to the real component, but the schematic component shape can be create as the user wish.
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The component above is 300 x 600 mils; the pads are 200 mils far and they have a diameter of 60 mils, but you can create the component bigger or smaller, or with the pads more or less distant, or with a different shape.
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First, place the component pads with ![]() In case of schematic component, every pad can be only of T0 type (square schematic pad) and cannot be modified. |
Now place the component outdraw (the component perimeter) with
. Select a 10 mils for the line thickness (but you can use
the value you wish) and Symbols fot the layer.
Place the CN1 and &1 labels, respectively above and beside of the component
(or in every place you like), using using, for example, a
text dimension of 60 mils.
The pin numbers can be placed, optionally, with the command
, using a text dimension of 48 mils and Pin Numbers for the layer.
Now, with or
select an area that include che component and the label &1, without the label CN1. To complete the elements
selection, click in the center of one of the pads, e.g. the middle pad.
Then, use to make the component CN1 from the hilighted
elements. Fills the form fields that will be showed with
"Pattern" = CN1, "RefID" = CONN?. The fields "Type/value" and "Modifier" can
be left blank.
Now, the component CN1 is ready to be used as
component CONN1 of TUTOR1.SCH electric scheme. Then open the file
TUTOR1.SCH, use to add the file COMP_SCH.LIB
into the library file list where Circad will search for components. Place the
component CONN1 with
, using "Pattern" = CN1,
"RefID" = CONN1. The fields "Type/value" and "Modifier" must be left blank.
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In the "PCB Pattern" field enter MP5, that is the connector
Molex - 5 ways, included in the Circad standard library file PCB.LIB.
It's not a must that a schematic component must be linked to a pcb
component with the same number of pins. In fact, Circad will try to link the
schematic component pins with the relative pins of the pcb
component.
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If this will not happens, you'll have an error when you'll create the
netlist of the electric circuit. The netlist is the
the whole of the wirings between schematic components
and the relative pcb components linked. If some pins of a pcb component
will be unused, you'll obtain only a warning message.
To verify the pin number of a pcb component, you can use the
command |
It will be possible to resize the pads, changing their shapes from square to round, or modifying their number, like swapping the pin 1 with the 4 and the pin 5 with the 2.
If you modify the pins parameters of the component MP5 placed into the library
PCB.LIB you'll automatically modify only the components MP5 that from the
time of the change will be used, for example with the command .
The MP5 components already present in other files will be not changed. This because
the link between schematic and pcb elements make a simple copy of
the component you get from the various Circad library to your user file. This is true both for
schematic and pcb components.
If you modify the pins parameters of the component MP5, placed in a single pcb user file, you'll change only the parameters of the component placed into the file.