eldo_user

Post-Layout Simulation
Parasitic Network Types
Parasitic Network Types
The types of Parasitic Networks handled by Eldo are:
• Capacitance (keyword C)
Coupling (capacitance between nets) and intrinsic (capacitance to ground) capacitors
represented as separate devices.
• Lumped capacitance (keyword CC)
Capacitors representing coupling + intrinsic capacitance.
• Resistance plus capacitance (keyword RC)
Resistors + capacitors representing coupling + intrinsic capacitance.
• Full RCC networks (keyword RCC)
Resistors and both types of capacitors.
Related Topics
Eldo Post-Layout Commands
Eldo Post-Layout Options
DSPF Backannotation Examples
Eldo Post-Layout Commands
The following post-layout backannotation simulation commands are available in Eldo:
• .DSPF_INCLUDE
Adds the parasitic elements described inside a specified DSPF file. Eldo loads the
specified DSPF file and backannotates the parasitic RCs in the specified DSPF file to the
pre-layout netlist. If the DSPF file contains the intentional devices, the geometric
parameters will also be backannotated to the corresponding devices in the pre-layout
netlist.
Three modes are available through the DEV=SCH[EMATIC]|DSPF|MIXED parameter:
o
o
SCH[EMATIC] specifies the DSPF file contains only the parasitics.
DSPF specifies the DSPF file contains both the parasitics and the intentional
devices. Sometimes it is more accurate to have the extractor generating a file
containing both. When this mode is specified, Eldo will take three actions:
i. Eldo will include the file specified in the command as if it was a .LIB command.
Eldo will therefore have two variants of the same subcircuit in its database, one
corresponding to the intentional devices which should be present in the circuit,
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Eldo® User's Manual, 15.3