Digital components, even though they do not show
the power and ground pins in the symbol (hidden pins), they are pre-configured to have the power and ground pins virtually connected
to the schematic's global power and ground nets. As long as the nets exist somewhere else in the schematic, the IC power and ground pins will be connected.
You can check this behavior if you follow the next steps:
- Place the digital component on the work area
- Double-click the component to open the Properties dialog and select the Pins tab
- Look under the Nets column for the power and ground nets
- (Optional) Double-click the cell and you can modify the name to any desire net name
- Click OK to close the Properties dialog
General tips for digital ICs:
- As long as the net name exists anywhere on the schematic, the digital component is virtually connected.
- By default, digital components are connected to
VDD, simply place the appropriate source symbol anywhere on the schematic to power up the IC. Select Place»Component, select Master Database, Sources Group and Power Sources Family. Locate the appropriate symbol in the Component field and place it in the work area.