User`s guide

15
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10 Mixed Analo
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/Di
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ital Simulation
3
Reset the power supply power and ground voltages as
required.
4
For any digital part instance that use the power supply must,
set its IPIN attributes to the power and ground node names
created by the secondary power supply.
Overridin
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CD4000 power suppl
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volta
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throu
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hout a schematic
Circuits using CD4000 parts often require power supply
voltages other than the default 5.0 volts supplied by the standard
CD4000_PWR power supply part. If needed, you can override
the power supply voltage for all CD4000 parts in a schematic.
The default power supply nodes used by CD4000 parts are
named $G_CD4000_VDD and $G_CD4000_VSS as created by
the power supply subcircuit CD4000_PWR. This supply
defaults to 5.0 volts. You can override the voltage across these
two nodes by defining values for the parameters named
CD4000_VDD and CD4000_VSS that are referenced by the
CD4000_PWR subcircuit definition.
For example, to change the CD4000_PWR power supply to 12
volts, referenced to ground, you would perform these steps:
1
Place an instance of the PARAM pseudocomponent from
special.slb.
2
Modify the PARAM attributes as follows:
NAME1 = CD4000_VDD
VALUE1 = 12.0V
DC4000_VSS is left at its default of 0 volts.
If the reference voltage also needs to be reset, the same method
can be used to define the CD4000_VSS parameter by setting the
NAME2 and VALUE2 attributes of the same PARAM instance.
For example, if you want the supplies to go between -5 volts and
+5 volts (a difference of 10 volts), you should set CD4000_VSS
to -5V and CD4000_VDD to +10V; as a result, CD4000_VDD
is 10 volts above CD4000_VSS, or +5 volts.