eldo_user

IBIS Models Support in Eldo
IBIS Buffers
• all_sm=YES|NO
For Series/Series_Switch buffers; setting all_sm to NO makes Eldo use only the first
non-zero Vds table to generate the current of Series MOSFET elements in the Series buffer.
The default is YES.
• keep_vds_monotonic=NO|YES
For Series/Series_Switch buffers; setting keep_vds_monotonic to YES will keep the Ids
current monotonic versus Vds values for a given Vgs. Default is NO.
• keep_vgs_monotonic=NO|YES
For Series/Series_Switch buffers; setting keep_vgs_monotonic to YES will keep the Ids
current monotonic versus Vgs values for a given Vds. Default is NO.
• rx_logic=0|1
For Input or IO buffers; if the input voltage on a_signal port is between Vinl and Vinh
thresholds then rx_logic will control the output voltage on the d_receive port. When
rx_logic=0 (default), the voltage on the d_receive port will be 0.5V (representing logic
"X"). When rx_logic=1, the voltage on the d_receive port will have the same value (state) as
the previous time step.
Note
If there are hysterises thresholds (Vinl+, Vinl-, Vinh+, and Vinh-) under the
[Model Spec] keyword, then rx_logic has no effect.
• para_begin param1=value1 param2=value2 ... para_end
For IBIS buffers that reference an external model, the parameter names and values specified
between keywords para_begin/para_end will be passed to the external model module.
• eldova=ON|OFF
For IBIS models that reference an external model in Verilog-A, Eldo will use its Verilog-A
compiler to handle these models if eldova=ON. Setting eldova=OFF enables these models
to be simulated with Questa ADMS. The default is ON.
• em_libname="logical_lib_name"
For IBIS models that reference external models written in any AMS language, this keyword
is optionally used. If no library is specified, the default work library will be used, specified
with the vasetlib command or the -lib option of the vasim command. Otherwise, the
specified logical_lib_name library is used.
• table_tune=value
Controls Eldo time step when the IBIS buffer is switching to obtain accurate output
waveforms. Table_tune accepts non-negative values. Default value is 8.
Setting a value of 1 forces Eldo to take into account all the switching waveform points, 2 to
take one point into account and skip the next, 3 skips two points, but takes into account the
third, and so on. Setting a value of 0 makes Eldo control the time step regardless of the
switching waveform.
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Eldo® User's Manual, 15.3