eldo_user

Speed and Accuracy
IEM Tolerance Parameters
• All independent or controlled sources, except:
o
Controlled sources defined by either the VALUE or TABLE statements (note: linear
and polynomial controlled sources are supported).
• All digital and mixed-signal macromodels.
• Only comparator and delay elements are supported among analog macromodels.
• Only the switch element is supported among switched capacitor macromodels.
• Accusim magnetic models are supported, but not those of Eldo.
In case a circuit or block contains an element not supported by IEM, this circuit or block is
simulated using Newton-Raphson and a warning message is issued.
Related Topics
Integral Equation Method (IEM) Algorithm
IEM Overview
IEM Tolerance Parameters
The following simulation algorithms may be used on a circuit depending on the setting of the
.OPTION line in the netlist and/or on the use of the (ANALOG) attribute on subcircuits:
• .OPTION NEWTON
In this case, the whole circuit is simulated in a single block using the Newton method.
This is the default algorithm.
• .OPTION IEM
In this case, the whole circuit is simulated in a single block using IEM.
• .OPTION BLOCKS=NEWTON
In this case, the circuit is partitioned (whenever possible) into one or more blocks.
Simulation inside each block is performed using the Newton method and relaxation is
undertaken between blocks using OSR. OSR is also used to simulate the non-Newton
part of the circuit.
• .OPTION BLOCKS=IEM
In this case, the circuit is partitioned (whenever possible) into one or more blocks.
Simulation inside each block is performed using IEM and relaxation is undertaken
between blocks using OSR. OSR is also used to simulate the non-IEM part of the circuit.
If a block contains either a GUDM, HDL-A, or FAS model, then simulation inside that
particular block will be performed using the Newton method. If no IEM blocks are created
Eldo® User's Manual, 15.3 1263