eldo_user

IBIS Models Support in Eldo
IBIS Component
• switch_isso=ON|OFF
Switch ON or OFF the effect of SSO (Simultaneous Switching Output) on the driver
current. The SSO effect is modeled in the IBIS file under the [ISSO PD] and [ISSO PU]
keywords. The default is ON.
• switch_composite_current=ON|OFF
Switch ON or OFF the effects of the power reference terminal current modeled by the
[Composite Current] keyword. The default is ON.
• check_model_spec=ON|OFF
Switch ON or OFF checking of the buffer input/output signals according to subparameters
given under the [Model Spec] keyword. The following subparameters are supported:
D_overshoot_area_h, D_overshoot_area_l, D_overshoot_ampl_h, and
D_overshoot_ampl_l. The default is ON.
• ibischk_soft=NO|YES
Used to control the golden parser (ibischk) reporting of IBIS version compatibility errors.
Setting to NO means the IBIS version number is checked for compatibility. Only the first
digit of the version number is checked, for example 4.x. Setting to YES releases ibischk
constraints on the IBIS version number. Default is NO.
Description
Equivalent subcircuit
Eldo uses the data under the [Component] keyword to generate buffers, interconnections,
package parasitics, and SPICE subcircuits or Verilog-A modules that represent external circuit
calls. Each component pin that references a model name or model selector name will be
associated with a buffer. The pins that are used as differential pairs under the [Diff Pin]
keyword will be connected to differential buffers, the other pins will be connected to singleended
buffers.
Series/Series_Switch models will be created according to the data under the [Series Pin
Mapping] keyword. Power interconnections are done according to the data under the [Pin
Mapping] keyword if available; otherwise internal source references are created for each buffer.
Package parasitics are added according to the package modeling type specified by the package
keyword, and the data available about the package model.
External nodes naming rules
Component pins that reference anything other than “NC” reserved keywords as the model name
will be added to the Eldo netlist as external nodes for the component equivalent subcircuit. If
the pin references an “NC” reserved keyword, but is used by the package model or exists in the
pin mapping of the series buffers, it will be added to the netlist also.
Additional nodes are also added to make access for buffers input, output, and control signals.
These additional nodes should be connected to ground if they will not be used.
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Eldo® User's Manual, 15.3