General:
o Nexxim linear analysis is available from Ansoft Designer by chosing to
install Nexxim customization from the Designer installation and installing
Nexxim from the Nexxim CD. No Nexxim licenses are required: Nexxim
linear analysis is unlicensed. Advanced Nexxim simulation capabilities
can be accessed by configuring Nexxim licenses.
o User customizable hot keys
o Ability to enable/disable an analysis
o User can "check passivity" on all imported data types (Nport, HFSS?
o Additional script commands
o C++ model editing wizard for Nexxim
o Linear components are now automatically configured for the system tool
o Toolbar customization with user set-able buttons
o The user can translate legacy circuits using right mouse menu click in the
project tree
o User can define callback scripts that run when a component is placed
- Component handling:
o Users can re-map dynamic link component pin assignments
o Component pin matching constraints relaxed
o Encryption of aclb's, aslb's, scripted footprints etc
o Designer now manages "models" that can be re-used in components
o Nport and field solver components now have similar options
o Subcircuits can be exported as component; optionally with solution data
o Various dynamic link enhancements that improve usability
o Users can drag and drop components from the main project tree or from the
component search tab onto a schematic
o Users can drag and drop models from the main project tree onto components in
a schematic
- Layout:
o Cross hierarchy snapping
o Layer manager is now modal and user can choose which columns to display
o Ruler now supports multiple segments
o User can define relative (hierarchical) coordinate systems
- Schematic:
o Schematic annotation improvements (colors, boxes etc)
o ERC enhancements
o User can add floating pins etc from right mouse menu in schematic
o User can have symbols change based on solver on demand selection
o Wiring improvements
o User can put plots or "reports" on schematic
o Reports can be dragged & dropped from the project tree onto the
schematic
o Mouse wheel can be used to move up & down, or with zoom when used
with the shift key
- PlanarEM:
o 64 bit support
o Multiprocessor support
o Progress bar for mesher
o Support for frequency dependent materials
o Access to PlanarEM output variables
o Fast sweep error tolerance is now user adjustable
o Frequency selective surfaces now support fast frequency sweeps
o User can now "clean stop" fast frequency sweeps
o Maximum amount of simulation data is kept after a user changes to frequency
sweep setup
o Additional information about fast frequency sweep progress is listed in
the simulation profile.
o PlanarEM supports terminal excitations
o Distributed Solve Option (DSO) for PlanarEM
- Dynamic links to Ansoft products:
o Users can push excitations for swept frequency EMI problems to SIWave
o New dynamic link to the 2D Extractor tool in Q3D
o Additional advanced dynamic link options when generating simulation setups
automatically
- Design Verification:
o DRC zoom to selected error
- Optimetrics:
o New Genetic Algorithm optimizer
- Reporter and post processing:
o Completely new user interface for better usability
o Fully scriptable
o Copy and paste of data or plot definitions from one report to another
o Support for re-usable report templates
o Improved data filtering & interpolation for Nexxim
o Reporter FFT/IFFT functionality
o Ranged functions for better data reduction. Examples include maximum, minimum,
rise time, overshoot...
o Enhanced eye diagrams
o Stacked plots
o Plots update dynamically when used with dynamic probes
MAJOR ENHANCEMENTS Nexxim V4.0
--------------------------------
- Nexxim user interface:
o Ability to compute the reciprocal response of subcircuits, Nports and
FieldSolver elements
o Usability enhancements to the Spice and IBIS component import dialogs
o User now has control of convolution on individual models
o TRL tool support
o New interface for Nexxim-based statistical runs / Monte Carlo
o User can use planarEM simulation on hierarchial components
o Simulation setups can be dragged and dropped between designs
o Linear analysis is now unlicensed
o Improved solution file serializer handling of large datasets
- Language features:
o .measure - Nexxim and Designer now support most HSpice .measure statements,
which can calculate maximum, minimum, average, integral, derivative,
RMS, peak-to-peak, and curve intersections for transient, AC, and
DC sweep analyses.
o Parser support for Spectre checklimit statements
- Envelope analysis:
o Bug fix associated with Envelope Analysis results
- Oscillator analysis:
o Improved two-tone oscillator transient initial guess;
o Improved escape from non-convergent oscillator analysis;
o W-elements are evaluated in time domain under oscillator analysis.
- HB analysis:
o The method for calculating the initial HB guess has been improved.
o Bug fix associated with sweeping mutual inductor in HB analysis
- Transient analysis:
o Support for simulating transient noise.
o Bug fixes include improved handling of minimum step size and discontinuous
events.
- Sparse Matrix Solver:
o Includes new sparse matrix ordering package delivering better performance
via the option -auto_select_solver=yes.
o Features partial pivoting strategy as an option for robust matrix solutions
via the option -do_partial_pivot=yes.
- DC Analysis:
o Bug fixes for convergence issues.
o Features pseudo_arc_length continuation scheme.
- Small Signal Analysis:
o Bug fixes for AC, noise and linear network analyses.
o The ability to do parameter sweep in addition to frequency sweep has been
added.
- Eye analysis:
o Support for eye analysis via statistical eye analysis of transient solutions
has been added. This methodology maintains accuracy while offering major
reductions in run time compared to conventional methods of eye analysis.
- System Engine:
o The newly added capability for system level mixed simulation seamlessly
integrates the system-level time domain behavioral simulation with
transistor-level transient simulation. Designers can include system
behavioral models and physical models (like transistor, S-parameter
data block, etc.) in the same design project and perform a transient
simulation on the design. Such hybrid integration enables designers in a
reasonable time period to simulate a complete system consisting of various
levels of abstraction, which complexity otherwise would demand a much longer
simulation time of a simulator operating on the transistor level only.
- New device models:
o Advanced Curtice 2
o Amorphous TF
o BSIM level 13
o Quadratic Curtice
o Cubic Curtice
o ISPDT
o MOSFET level 38
o VSPDT
o Juncap2
o LDMOS20
o LDMOS30
o LDMOS40
o CMC MOSvaractor
o CMC R2
o CMC R3
o TOM2
o Dynamic probes
- Improved models:
o BSIM4
o HICUM Level 2 2.22
o Random Bit Source
o HiSIM updated to latest version: HiSIM2.4.0
o S-elements
o Verilog-A support
o IBIS
Nexxim Model features, new and improved:
----------------------------------------
- IBIS:
o IBIS driver schedule support
- Causal low-pass filter:
o Developed causal low pass filter with only known real part
- Microwave models:
o Introduced power combiner to the list of ideal microwave models
- Chain-based ABCD:
o Added an instance parameter "delayhandle" to the model so that the user can
choose to do state-space based rational function fitting during time domain
and/or transient simulation versus default: convolution.
- CPW-based distributed library:
o Added different many co-planar waveguide models.
- Distributed models:
o Added several ideal distributed models to the ideal distributed library to
be used with Smith Chart tool in Nexxim.
- Edged TEE model:
o Enhanced.
- GCPW-based distributed library:
o Added different many grounded co-planar waveguide models.
- HCOM ideal_tuner:
o Enhanced the existing passive tuner to an ideal tuner that includes as well
as matches all of the HCOM ideal tuner features.
- Field solver model:
o Enhancements have been made to the field solver model. When ground
conductors are used as reference planes we need to make sure the minimum and
maximum length of the dielectric layers extend to cover the ground
conductors.
- Frequency-based R L C devices:
o Transient Analysis can use frequency-based capacitor, inductor, and
resistor. Previously, the frequency-based capacitor, inductor, and resistor
were supported only in frequency-domain analyses.
o A new parameter, tran_eval_freq, has been added to the net-list format for
these three elements to allow them to be used with transient analysis.
When tran_eval_freq is present in the net-list entry, Nexxim can run a
transient analysis on circuit containing the frequency-dependent capacitor;
inductor, or resistor.
- Inductor Q:
o Analytically added causality correction for the special cases of exponent
selection, i.e. exp=1/2 and 0.Fixed DC resistance calculations for the
inductor with Q model.
- Modulation sources:
o Added several IQ-based modulation sources to the modulation sources library.
In particular, the quadrature amplitude modulation (QAM), phase shift keying
(PSK) and the continuous phase modulation (CPM) schemes are included.
- Negative impedance converter:
o Added DC path to ground to all the nodes needed for the model to run with
the HFSS dynamic link.
- S-elements:
o Implemented new "passive" flag from Hspice; checks passivity of input data
if passive=1. If passive=2, checks passivity of state-space fit.
o Supporting Hspice's DELAYHANDLE=ON (synonym for convolution=3).
o Added s_element.errorif option. By default, 1. Rejects state-space model
if error is larger than 10%.
o Convolution now uses interpolation and extrapolation flags.
o Added test_sss option, default =1; set to zero to bypass the testing of the
cached state-space systems.
o Reports fitting error for convolution=1.
o Added option s_element.rational_fitting_iteration_limit, default=2, to allow
for fine tuning rational fitting.
o Added trace message for differing port impedances.
o Added MOR singular perturbation option (s_element.mor_sp=1): preserves DC
fit while reducing the order of the model.
o Added limit to Q (quality factor) of poles in rational fitting.
Default is 1e4, can be changed with new option s_element.q_limit.
- TFT:
o Model improvements
- W-elements:
o Minimum number of frequencies for the W-table is now 100; fewer than that
will be interpolated.
o Added limit to Q (quality factor) of poles in rational fitting.
Default is 1e4; can be changed with new option s_element.q_limit.
- VSIQ:
o Fixed the polarity issue with the model.
- Verilog-A support:
o Events support added: Nexxim now supports initial_step, final_step, cross.
System tasks support have been extended.
o Nexxim now supports $display, $strobe, $write, $debug and $monitor.
"genvar" support added
o Asian characters supported inside comments
internal nets supported
o Various other Verilog-A enhancements
