S4.5 Pins not connected on the footprint may be omitted from the symbol
Often a component has pins that are not physically connected. Even these pins should be included in the symbol. Refer to the requirements for hidden pins.
However in some cases unconnected pins may be omitted from the schematic symbol.
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Pins may only be omitted if they are never to be connected under any circumstances
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Unconnected pins may only be omitted if including them would make the symbol unnecessarily large.
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If pins are designated
NC
but the datasheet specifies that these must be pulled to ground or otherwise connected to a specific net, then these must be shown on the schematic symbol -
The footprint filter must include the pad count of the footprint if the symbol has omitted pins (see also requirements for footprint filters)
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BGA?144
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QFN?20
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