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Advanced Design System 2021 Release Notes

For general information about Advanced Design System (ADS), visit ADS webpage at http://www.keysight.com/find/eesof-ads. 

Starting ADS 2020 release, the Linux system requirements have been updated:

  • Support for Redhat 5.x has been discontinued.
  • Updated the system libraries and rpm files. Following is the list of minimum patch versions required:
    • Redhat 6.10
    • Redhat 7.2
    • Suse 12.2
    • Suse 11.4

Few ADS features will not work properly, in case you have installed lower patch versions than the above-recommended versions.  

For more information, refer to Supported Platforms.


Feature Updates

Design and Technology Management

  • Improved workspace performance when many libraries on a network path are included.
  • Enhanced Copy Cells command to handle references of Data Display files, to copy a cell from another workspace and provide a utility for finding and fixing missing references.
  • Enables the third-party version control systems to support tagging.
  • Supports "Patch" components.

Known Issues

  Back to Feature Updates

Design Editing

  • Enhanced Layout Constraints Manager:
  • Enhanced Ground Plane:
    • Ability to 'Lock' placement of a ground plane.
    • Ability to preserve the ground plane net during copy/paste.
  • Enhanced Keepout:
    • Ability to create a circular Keepout.
    • Ability to create a Keepout from an existing polygon, and vice versa.
    • Ability to edit a Keepout with visual cues of edge and vertex handles, similar to polygon editing.
    • Ability to include/exclude Keepout objects in selection operation.
          For more information, see Creating Keepout.
  • Enhanced Routing:
    • Teardrops, a special connection pattern that optimizes the trace-to-pad, trace-to-via connection for improving the manufacturability of the layout, are inserted based on the rules that define the layers, height, offset, angle attributes.
    • Improved snapping, joining other interconnect, redundant segment removal, and back-tracking vertex during trace editing.
  • Enhanced Multi-technology Smart Mount:
    • Multi-Mount type, in addition to Bottom Mount and Flip Chip mount types, is added to support run-time decision on the mount type for the chip.
    • Ability to defined Chip to Module alignment for a Smart Mount Pcell via the File > Customize Pcell dialog box.
          For more information, see Creating a Simple Smart Mount Component.
  • Oversize/undersize functions now preserve true curves.
  • General Editing Improvements:
    • Context-sensitive menus in Layout window and Navigator docking window are re-organized to make object-specific editing handy.
    • Instance position can be conveniently edited in the Properties docking window.
    • Instance’s OpenAccess Orientation is displayed in the Info docking window. 
    • AEL APIs are available to enable padstack creation/editing and general layout object editing.

Known Issues

  Back to Feature Updates

Data Display

  • DDS equations management made easy:
    • Equation’s dependency information can be viewed via the Find > Show Hierarchy command.
    • The textual-based spreadsheet-like contents management system, the Expression Manager, provides a complementary method to the traditional graphics system for adding, viewing and editing equations and traces from all pages. The Expression Manager is dock-able to a DDS window and interoperates with the graphics system.
    • Facilitate the conversion of a DDS equation to an AEL function via the Command Line dialog box invoked from the Expression Manager.
      For more information, see Expression Manager.
  • Ability to bulk editing of DDS plots and traces—for example, inserting, editing, replicating traces for multiple plots, changing trace attributes or plot attributes.
  • A new tool, Command Line, similar to ADS design environment’s AEL Command Line dialog box, enables exploring, editing and saving AEL functions intended for DDS equations. For more information, see Using Command Line.
  • Ability to import a DDS AEL file, and define the AEL file loading frequency and timing, via the File > Import > AEL File menu. The loading of AEL file can be triggered at the workspace open, library open or ADS startup, respectively. For more information, see the Importing an AEL File in Data Display section in Data Display Basics.

  Back to Feature Updates

Circuit Simulation

  • General
    • Stability analysis
      • Improvements of the Stability analysis flow to give more insight to designers.
      • Support for multiple--transistor stability analysis based on Ohtomo’s loop gain is added.
      • Direct output of the Winslow Stability Probe has been simplified to reduce redundancy.  
        • As an example, GammaG and GammaL have been deprecated as they result from an easy computation from ZG and ZL.
      • Many underlying functions have been updated to improve efficiency and robustness.
    • Design with Modulated Signals
      • New smoother flow to embed SystemVue Virtual Test Benches (VTB) inside ADS. 
        • VTBs can be updated without needing a new ADS version. For more information, see Virtual Test Bench.
      • Regular Envelope can now be parallelized on multiple machines leading to huge speed-ups.
      • Distortion EVM: 
        • Streamlined the flow for an easier setup for designers.
      • Improvements of Fast Envelope for highly non-linear circuits (Level5).
    • Job Distribution
      • Support of SiteCluster (Pilot Phase - for Linux only)
        • ADS 2021 will boast enhancements in its Simulation Manager to better handle job submissions to workload management platforms starting to unify setups among Keysight Circuit and EM simulators. 
        • As a consequence, ADS legacy Distributed Mode will not be supported any further starting ADS 2022 as being a subset of ADS Simulation Manager.
    • GoldenGate in ADS
      • Starting ADS 2022, the integration of the RFIC simulator GoldenGate inside ADS will no longer be developed as the main features that customers requested have now been natively integrated inside the ADS simulator. There is no change for GoldenGate inside Virtuoso.
  • ElectroThermal
    • Faster Electrothermal Circuit Envelope simulation Multiple encrypted thermal tech-files supported in Electrothermal.

Known Issues

  Back to Feature Updates

HSD Design

  • SerDes

    • New TDECQ measurement in ADS with FlexDCA_Probe. 

      • Allows user to do a parametric analysis of designs for TDECQ

    • New Infiniium_Probe that sends ADS simulated waveforms to Infiniium offline software for advanced waveform measurements. 

    • Electrical-Optical-Electrical (E-O-E) system simulation with VPIphotonics. 

  • DDR/Memory

    • New IBIS Model Editor for pin-based model setting and batch simulations.
      • Allows PRBS (user defined) and equalization setting per pins
      • Allows batch simulation for IBIS model corner cases and model selectors
    • New batch simulation setup for corner cases, model selector, and so on. 
      • Provides automatic variable list creation from the IBIS model setup
      • Allows user to easily create a batch simulation setup either by List mode or Sweep mode
      • Significant improvement in simulation usability, especially for a bunch of overnight batch simulation runs
    • New Statistical Simulation mode for DDR5 AMI.
    • New non-IBIS flow support. 
      • Allow users to start Memory Designer without IBIS models
      • Works for Controller and Memory.
    • Improved parser for PCB data fiIes

      • Allows user defined custom parsing rules

      • Supports multiple rules
    • New Design Exploration solution with deviation from the target value and pass/fail report generation. 
    • Probe and Compliance test settings  in Memory_Probe are now separated to minimize compliance testing errors.
    • New Memory Interface AMI Model Builder -  Memory Designer license and a special installation is required. 
  • EM-SI
    • Modified the recovery of lost cells in VMesh (SI mesher).
    • Via Designer - Advanced features such as micro-vias no longer require a FEM license.
    • Via Designer - Accuracy for higher frequencies.

    • Via Designer - Notes and name of simulation in Via Designer are now editable.
    • Via Designer - Support for adding Teardrop and Diving Board for line feeds.
    • Via Designer - Support for Via Array.
    • Via Designer - MicroVias with conical or cylindrical shape.
    • The new RapidScan-Z0 feature allows quickly scanning signal nets reporting any gross errors in the design. It allows you to visualize the traces and sections that are out of specifications.

    • Parallel frequency simulations for SIPro simulations, requiring HPC 1-pack licences.  N parallel jobs require (N-1) PathWave_EM_HPC_1-pack licenses. 
      If a combination of multiple 1-pack HPC and a 8 pack HPC licenses is available, and N = 2, 1 HPC 1-pack license is checked out.  If 2< N< 8, the 8 pack HPC license is checked out, if N > 8, the 8 pack license and multiple 1-pack licenses are checked out.
    • SIPro simulations to remote machines and cloud instances via simulation service.
    • Various robustness and accuracy improvements for SIPro simulations. 
  • EM-PI
    • DC IR Drop allows for asymmetric voltage tolerances.
    • DC IR Drop results Power Tree expansion improved for parallel and cascaded VRMs.
    • AC Analysis auto loads sink excitation for field plots.
    • Fast update of PDN impedance plots for enable/disable of components. 
    • AC Analysis improved the handling of schematic defined library models, multi-pin touchstone models, and embedded components. DeCap optimization works with library models, and results Loop Inductance works with embedded components.
    • Generate Analysis script now includes user-defined virtual pins.
    • ODB++ export capability (beta version)

Known Issues

  Back to Feature Updates

EM Simulation

  • RFPro

    • Analyze the impact of etch bias (over/under etch) and registration bias (layer misalignment) without the need for parameterizing the layout. For more information, see the Process Variation section in Full EM Extraction Analysis.
    • Simulation Service supporting cross-platform simulations. A Windows/Linux client can submit a simulation to a Linux cluster. In case you have an interest in trying out this new functionality, contact Technical support and guidance will be provided to configure this simulation service.
    • ADS now offers the possibility to place an encrypted EMPro 3D component inside the layout. Such a component can be seamlessly simulated inside RFPro ensuring the protection of the IP.

      The encryption of a 3D component requires PathWave EM Design (EMPro) 2021 or later.

    • Pilot introduction of native placement of 3D components (solver balls and bond wires) inside RFPro. Enable the Show Beta Functionality from the Tools > Options > General tab to gain access to this new capability.
    • Momentum Generation 2. For more information, see Advanced Simulator Setup for Momentum.
      • Fast layout preprocessing.
      • Fast simulation of designs with large via arrays and patterned ground planes.
      • Enable Mesh Domain Optimization to speed up the simulation of a User-Defined EM Extraction analysis.
    • FEM Generation 2. For more information, see Advanced Simulator Setup for FEM.

      • Supports the simulation of a layout containing EMPro 3D components and 3D components natively placed in RFPro.

      • Supports the simulation of a design with an encrypted substrate or containing an encrypted 3D component.
    • New Create Reference Pin On Layer option to serve as an implicit reference in the I/O or Component Model port definition.

    • New Create Delta Gap Port option to easily probe current in a design or tune a design.

    • New Component Includes Area Pins In Net checkbox on Components to influence how component areas pins are processed
    • Enhanced Component Model port editor facilitates the component port setup

    • New Show S-Parameters/TDR Results context menu in the Setup pane upon a selection of multiple analyses, that allows to easily compare results.

    • ADS 2022 will unify the EM 3D viewers to benefit from the latest 3D viewing enhancements delivered in the RFPro platform. The legacy 3D EM viewer will not be accessible starting ADS 2022.

  • Momentum

    • The material of the vertical cell of an edge pin on a thick conductor will be considered to be perfectly electrically conducting (PEC). This ensures that the pin's surface current can redistribute to all four sides of the thick conductor without excess resistance.
  • FEM

    • The estimation of the calibration inductance no longer considers the portion of the impedance line path that passes along or through conductors.

  • Coilsys
    • To propose a better experience for RF pCell generation such as inductors, baluns,  ADS 2021 will be the last major release to support the Coilsys feature in its current form in ADS. It will be embedded in RFPro benefiting of the latest features available in our EM platform including access, on top of ADS, into other frameworks such as Cadence Virtuoso and Synopsys Custom Compiler

Known Issues

  Back to Feature Updates

Power Electronics

  • Added Power Electronics Model Builder tool to extract a Si/SiC Power MOSFET model from a datasheet using an automated flow. For more information, refer Power Electronics Model Builder

  • Added a generic template to extract a Si/SiC Power MOSFET model from a datasheet for users who would like to have more control over their extraction flow (2020 Update 2.0)
  • Added a Generic Power MOSFET component to the Power Electronics library. (2020 Update 2.0)
  • Fixed an issue in circuit excitation that affects Radiated EMI results.
  • Fixed a bug in the IGBT example workspace. (2020 Update 2.0)

Power Electronics Professional (PEPro)

  • Radiated EMI Testbench in PEPro (ADS 2020 Update 1).
  • Fixed a bug in the show/hide button in the PEPro Layer Display Settings Panel. (2020 Update 2.0)
  • Fixed a bug in the information icon in the select dataset dialog in circuit excitation. (2020 Update 2.0)
  • Fixed a bug in the closed loop buck converter example workspace. (2020 Update 2.0)
  • Fixed a bug in the field scale properties. For more information, see PEPro. (2020 Update 2.0)

Design Import/Export

  • Added support for import of netlists with diode model temperature coefficient parameters. (2020 Update 2.0)
  • Added support for import of LTspice netlists with component values enclosed in curly braces. (2020 Update 2.0)

Known Issues

  Back to Feature Updates

Layout versus Layout (LVL)

Compare two versions of a layout and highlight differences in the layout window. Select layers to check. Run interactively from a Layout window or run batch jobs using the command interface.

For more information, see Getting Started with Layout Versus Layout.

  Back to Feature Updates

Design Rule Check (DRC)


  • DRC Dialog recognizes the DRC configuration for a PDK, including callback files.  Load statements in setrule can be removed. 
    For more information, see DRC Functions > Library Configuration

Assura DRC Link

  • DRC errors are displayed using the bounding box from the error report if shape information is not available in the results file.

Calibre DRC Link

  Back to Feature Updates

Layout versus Schematic (LVS)

Calibre LVS Link

  Back to Feature Updates

Design Kits

  • Updated the Si-RFIC PDK Model Include Utility for the following:
    • New configuration functions to configure PDK for the utility. These new configuration functions are easy to use and maintainable.
    • Set the hierarchy policy from the settings dialog itself.
    • Scalable user interface.
    • Rename the scenario.
    • Backward compatibility for previously configured PDKs.
    For more information, see Si RFIC PDK Model Include Utility.
  • Updated the Non-Linear Demo Kit for the following:
    • Added an example of custom DRC rule to calculate the airbridge aspect ratio.
    • Removed the DRC Error Matching rule.
    • Added substInfo.txt file that includes detailed information on different substrates included in the design kit.
    • Updated the form names associated with the "Type" parameter of transmission line components to support legacy designs created before ADS 2020.
    • Updated DRC setrule.ael file. Now DRC rule callback will be loaded by the DRC configuration present in boot file of the design kit.

Known Issues

  Back to Feature Updates

Netlist Exporter

Removed extra “.end” statement from the netlist.

  Back to Feature Updates

Virtual Test Bench (VTB)

For general information about Virtual Test Bench (VTB), visit VTB webpage at http://www.keysight.com/find/eesof-ads2021-vtb.

For general information about Virtual Test Bench (VTB), visit the VTB webpage at http://www.keysight.com/find/virtual-test-bench.

  • From ADS 2022:
    • Verification Test Bench (VTB) is now called Virtual Test Bench (VTB).
    • To install files that are required for the VTB functionality along with the ADS installer, you need to download a separate VTB installer for both Windows and Linux and manually install the VTB.
    • If you have already installed ADS and find VTB functionality is missing, then you need to download and manually install the VTB.
    • If you want to uninstall, then you need to manually uninstall VTB separately for both Windows and Linux.

For more information, see  VTB documentation.

For more information, see VTB documentation.

Known Issues

  Back to Feature Updates


  • ADS 2021 requires: a) the version 2020.02 of the EEsof EDA licensing software, b) a minimum code-word version 2020.02 or above, and c) the licensing server software, lmgrd and agileesofd, to be upgraded to at least the same versions as what are included in EEsof EDA Licensing software 2020.02. ADS 2021 will not start if any of these requirements is not met. Refer to the License Codeword Version Compatibility Table.
  • In the EEsof EDA License Tools version 2020.02, licensing vendor daemon (agileesofd) is integrated with FlexNet FNP version (Windows) and FlexNet FNP version (Linux) of FlexNet license manager daemon (lmgrd). For the Windows platform, ADS installer will automatically set up these two new license server daemons by default for the local node-locked license users; for the Linux platform, you need to follow the Setting Up Licenses on Linux instruction to complete the licensing configuration process. For more details, refer to Licensing (For Administrators).

Known Issues

  Back to Feature Updates

Known Issues

Design and Technology Management

  • Using ADS 2020 with pycell studio 2018 (PyCell Studio Packages: Release O-2018.09) might prompt you an OA version mismatch warning message on the linux terminal. However, there is no impact on the iPDK flow in ADS.
    Linux terminal message:
    Requested minor API version '518', which is supported by OpenAccess build '22.50.030' is newer than the minor API version '514' of the shared library of OpenAccess build '22.50.043'.

  • The Express Pcell plugin that comes with Virtuoso IC version 6.1.8 does not work with ADS 2020 due to an OpenAccess version mismatch, but the Express Pcell plugin will work with ADS 2020 Update 1.0 and 2.0.  

    • When running ADS 2020, set the LD_LIBRARY_PATH environment variable path to point to the directory from IC version 6.1.7.

    • Upgrade to ADS 2020 Update 1.0
  • The Express Pcell plugin that comes with older versions of Virtuoso IC version 6.1.7 may crash during a simulation with ADS 2020 Update 2.0 due to a third party incompatibility but may work with newer versions above IC version 6.17_722 and up.

  • AEL constants are protected and should not be modified in any DDS expressions.  An AEL error will be issued in case an attempt to modify an AEL constant occurs.

  • Python Datalink
    • When using Connection Expert 2019 connected to Lan Instruments, there may be error messages during dl_visa_query() and dl_visa_write().
    • Exceed on Demand: Note that in some cases, EoD settings may need to be configured to properly display Spyder.  Please contact your EoD support representative for additional guidance.

  Back to Feature Updates

Design Editing

  Back to Feature Updates

Design Guide

  • Unable to unarchive HDMI design guide from the Schematic view (DesignGuide > HDMI).
    • Unarchvie using the old ADS version.
    • HDMI design guide will open in case it is already unarchived.
  • Simulating the "1_Sim_CA" design in the DDR4 CTB design guide prompts the netlist error.
    Workaround: Open the schematic design "PatternGen_CA_Continuous" and arrange the pin numbers in order.
  • Simulating of schematics in the HDMI_Link_Simulation design guide prompt the netlist error.
    Workaround: Open the schematic design “HDMI_Diff_RX” and arrange the pin numbers order in order.

Design Kits

  • A design created using ADS2020 Non-Linear Demo Kit (NLD) and using NLD discontinuities like demo_bendP, demo_stepP, demo_teeP, etc. will not work as expected in ADS 2021.
    Workaround – In ADS 2021, either update the design with the latest NLD i.e. NLD shipped along with ADS 2021; or continue to use the NLD that was shipped with ADS 2020.

  Back to Feature Updates

Circuit Simulation

  • General

    • Batch simulation with local simulation manager runs successfully on Linux and Windows. However, when the simulation is rerun again the second time on the same schematic, then the simulation is terminated with an error but jobs are run successfully. 

      Workaround: You should clean up your <workspace>/simulation directory to avoid the simulation termination error.

    • The User-Complied Model (UCM) might not work in ADS 2021 on Windows 7 platform with Visual Studio 2019.

    • When using GoldenGate in ADS 2020 Update 2.0, some of the library files of RFIC cockpit options are not getting loaded due to license incompatibility. It is recommended to use ADS 2020 Update 1 when using GoldenGate in ADS. 
      For details on license compatibility, see License Codeword Version Compatibility.

    • Simulation Manager may not work on Windows and throw exceptions for some designs.

    • ADS 2019 will not be compatible with Verilog-A files, which have been encrypted before ADS 2019. There is no change for non-encrypted Verilog-A files.

    • TMI models are supported for pure Hspice syntax only. The support of hybrid syntax (mixing Hspice and Spectre) is planned for a future release. 
    • BSIMSOI models using TMI modeling is not supported yet. Classical BSIMSOI models are supported as before.
    • TMI Aging simulations are not supported 
  • ElectroThermal

    • ETH simulation terminates with an error when symlinks are used for simulation and data directories.
      Workaround: Make sure that the physical directory names and their symbolic link names are named as 'data' and 'simulation'.

    • You may not be able to start a Transient/Envelope Electro-Thermal (ETH) simulation only when the same testbench is open in the viewer of Transient/Envelope thermal results. You need to close the viewer before launching a Transient/Envelope ETH simulation.

    • The electrothermal simulation will not run on designs created using Smart Mount for Multi-Technology feature.

    • Paths set while configuring the ETH controller may need to be updated when the workspace is moved across operating systems.

    • On a fresh Linux machine, electrothermal simulation fails with the following error message:

      Heatwave returned an unknown error code 127.

      Workaround: The error could be due to missing packages, for example, libpng12. Verify your system meets the requirements using the linux_sys_check.sh script. For more information,  see Checking Installed RPM Files and the Operating System Version.

    • If you get licensing errors while running a thermal simulation, you may need the following workaround.
      Workaround: Rename the file  $HOME/.eesofrc. For example,  $HOME/.eesofrc-orig.

    • Electrothermal does not support remote simulation, batch simulation, Monte Carlo, tuning, Optimization, and Measurement Equations. Also, you cannot sweep directly on the DC controller.

    • All libraries referenced in a layout should use the same layout resolution, namely the OA database units (DBU) per user unit (UU).

    • You cannot run both a transient and envelope simulation on the same design from one testbench.

    • The calculation of power dissipation from passive components other than resistors may not be correct in harmonic balance simulations.

    • Electrothermal does not support the transient or envelope simulation that is controlled by a ParamSweep.  

    • If you get "Maximum timestep reduced to half of shortest transmission line delay " warning, it can lead to transient simulation to not converge   
      Workaround: Unselect "Limit timestep for Transmission Line" option on Time Setup tab of Tran component to get it work.

    • On Linux, if you specify the THERMAL_DIRECTORY variable in eesof_lib.cfg file using backward slash (..\thermal), the thermal simulation does not run properly.
      Workaround: Specify the THERMAL_DIRECTORY variable using forward slash (../thermal) instead of backward slash.

    • The ETH viewer does not support 4K displays. A few instances of text and icons may appear distorted. 

    • You receive an error message in substrate editor that you cannot use the same layer number more than once. You can safely ignore this error during thermal technology export.

    • On a fresh Windows 10 system, Electrothermal simulation terminates with an error. 
      Workaround: Install the following Microsoft Visual C++ runtime components: 


  • DDR Design 

    • You receive an error message to check port numbering when performing simulation with SnP component for differential configuration.
      Workaround: Select the first option in Pin Configuration for the SnP component.

  Back to Feature Updates  

HSD Design

  • SerDes
    • While running simulation, using both the Infiniium_Probe and FlexDCA_Probe in the same schematic can cause a communication error (socket 5025).
      Workaround: To fix this issue, use one of the following methods:

      • Use either the Infiniium_Probe or FlexDCA_Probe in the same schematic.

      • On FlexDCA change the socket number to a different number from the default 5025, and use the changed number in the FlexDCA_Probe’s dialog “Connection-Setup” tab.
    • TDECQ measurement in FlexDCA probe is not compatible with ADS optimization.
    • The VPI DS version 11.0 (latest) will throw an error for .vtmu file of VPI DS version 10.0 or 10.1 "ADS-VPI DS Python interprocess communication failed error" when performing the simulation. This error is due to registry not being updated during a new VPI DS version installation.
      Workaround: The registry should be cleaned by performing the following steps:
      1. Open the Windows registry.
      2. Remove all the leftover keys for any of the VPI DS versions which are no longer installed.
    • You receive an error message when runtime libraries for some of the ADS example ibs files (for old AMI models) are unable to get installed automatically during the ADS install.  The error appears even though the ibs file is supported on specific platform. 
      Workaround: Microsoft Visual C++ 2010 runtime library is required to run the dll files. Download the following library if it is not installed:


  • DDR/Memory
    • Design Exploration solution does not work with Batch Simulation when "UseSeparateProcess" is enabled. 

    • SIPro/PIPro, Via Designer 
      • On Windows 10 with Intel HD graphics, Via Designer may show an error message ‘Failed to use the connection between ADS and Via Designer.’  This has been isolated to the latest release of Intel HD Graphics drivers (23.xx.xx.xxxx).
        Workaround: Downgrading graphics driver to the previous recommended driver resolves this issue (e.g.,, A05).
      • DirectX 9 as graphics driver is no longer supported. DirectX 11 is thus be used by default. Run "diagdx" to verify which DirectX version is supported on your system.
    • SIPro/PIPro
      • ADS 2021 is not compatible with the latest available Samsung component models released in June 2018. The support for the component models is planned to be added in an upcoming update release.
      • Simulation failure when using components with S-parameter models or for which the model is defined using a lib/cel/view in case the Updating model does not require new simulation is not set. As a workaround, turn on the option. For PI-AC simulations, the options are turned on by default, for SIPro, this needs to be turned on explicitly.
      • If you run SIPro/PIPro on a fresh machine with Suse 11 or Redhat 6 installed, you may encounter the critical error "EMPro exited unexpectedly during execution." This is related to the graphics driver software.
        Workaround: Upgrade to the latest vendor-specific drivers and OpenGL libraries for the graphics card. 
        Alternative workaround: 
        Run the following commands:

        cd $HPEESOF_DIR/fem/2020.20/linux_x86_64/bin
        ./startempro --personality=sipi--driver=x11

        Ignore any license related error messages that may show up on executing these commands. The driver setting is saved per personality for future sessions.

      • With split domains on, there are no results available until simulation results are available from the last simulation, or even after the simulation.

      • When running an SIPro parallel simulation through a simulation service with a node-locked license file, and the simulation is not proceeding, this can either be because no HPC licenses are available or the simulation service not being available. This may result in a hour time-out before the simulation proceeds or fails.

  Back to Feature Updates

EM Simulation

  • RFPro
    • The FEM and Momentum Generation 2 flows are state-of-the-art solvers but still evolving. In case it does not handle your design, switch back to Generation 1.
      • TML (waveguide) ports are not yet supported in FEM Generation 2
    • Multi-technology designs cannot be analyzed with Momentum.
      Workaround: Use the FEM simulator
    • Project load fails with the error 'OccDesign::getNet: key not found' when a layout shape has a multi-bit net name (e.g. 'd<7:0>' or 'a,c,net1').
      There is no workaround.
    • With McAfee Endpoint Security (ENS) enabled, the Momentum surface current visualization hangs.
      Workaround: Disable the "Enable Adaptive Threat Protection" flag in McAfee ENS.
  • RFPro and 3D Viewer

    • If you run the tool on a fresh machine with Suse 11 or Redhat 6 installed, you may encounter the critical error "EMPro exited unexpectedly during execution." This is related to the graphics driver software.
      Workaround: Upgrade to the latest vendor-specific drivers and OpenGL libraries for the graphics card.
      Alternative workaround: Launch the tool and force it to use the X11 driver. You can do that by executing following commands in a shell:

      cd $HPEESOF_DIR/fem/2020.20/linux_x86_64/bin
      ./startempro --personality=rfpro --driver=x11
      ./startempro --personality=3dview --driver=x11

      Ignore any license related error messages that may show up on executing these commands. The driver setting is saved per personality for future sessions.

  • EM Setup
    • On a Virtual Windows 10 system with Microsoft Hyper-V Video display driver, the 3D EM Preview with EM Setup Preprocessing may bring up a dialog with a Hoops error, and, after suppressing the dialog, it opens up blank. 
      There is no workaround.
  • Distributed simulations
    • The example implementation of the sitecluster command for LSF clusters may lead to failing simulations if the path or number of threads is too large.
      Workaround: See the workaround details in the sitecluster documentation.

  • Import/Export

    • Exporting with MentorDA link does not work with the latest Mentor Graphics software Version VX2.6. 

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Power Electronics

  • PowerMOS_SiC power devices operate under a very wide range of voltage and current slew rates and it is a challenge to create a model that converges under all conditions – especially conditions that depend upon what components are connected externally to the power device in the circuit schematic. Please contact technical support if you encounter such an issue when attempting to use this model.

  • If you run PEPro on a new machine with Suse 11 or Redhat 6 installed, you may encounter the critical error "EMPro exited unexpectedly during execution." This is related to the graphics driver software.
    Workaround:  upgrade to the latest vendor specific drivers and opengl libraries for the graphics card. 
    Alternative workaround
    Run the following commands:

    cd $HPEESOF_DIR/fem/2020.20/linux_x86_64/bin
    ./startempro --personality=sipi--driver=x11

    You can ignore any license related error messages. The driver setting is saved per personality for future sessions.

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  • While installing a new version of ADS, if you see “Previous version detected” error even after you have already run the uninstaller for that version of ADS, you may need to manually uninstall ADS before installation of the new ADS. To manually uninstall ADS, perform the following steps.
    1. Exit the current ADS installation session if it is running
    2. Remove or rename the file .com.zerog.registry.xml  under the folder  C:\Program Files\Zero G Registry . Both the folder and the file are by default hidden, so you may need to change the folder viewing setting to show hidden files and folders, do so via the Advanced settings of the View tab in the Windows Folder Options dialog box.
    3. Remove the ADS installation directory through the Windows Explorer.
  • After performing the above steps, you can re-start the ADS installer.

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  • You may observe additional License Usage when Client Machine reconnects to network after intermittent disruption.
    Workaround: In case of network interruption on the client machine, to reclaim the inactive licenses, a TIMEOUT can be set using the TIMEOUTALL feature in options file (minimum time period of 15 minutes). The inactive license may stay checked out for this period of time.

  • Unable to install Licensing Hardware Key Drivers on Windows.

  • Workarounds:

    • Turn off UEFI Secure Boot (BIOS) and use the default 6.3 version of the Wibu key driver delivered with the EEsof Licensing tools.

    • Turn on UEFI Secure Boot (BIOS), upgrade to ADS 2020 Update 2.0 and use the 6.51 WibuKey driver version available in the 2020.02 License tools installation directory.

    You will not be able to run older ADS releases with the 6.51 WibuKey dongle drivers

  • You may observe issue in recognizing more than one FLEXID on Linux platform with the 2020.02 license tools.
    Workaround: Consolidate your licenses to one FLEXID and configure the same.
  • Setting FLEXLM_DIAGNOSTICS to the highest level (FLEXLM_DIAGNOSTICS=3) on Windows client may cause a crash during license checkout. Flexera is investigating this issue.
    Workaround: It is recommended not to use the FLEXLM_DIAGNOSTICS on Windows clients or use it at lower level (FLEXLM_DIAGNOSTICS=1 or FLEXLM_DIAGNOSTICS=2).
  • WibuKey 6.5 software driver is not supported on SuSe 11.
    Workaround: Use the older WibuKey 6.30 software driver (WkRt-Lin-6.32.1504-500.x86_64.rpm).

  • Licensing may not support a license file path that is too long. This will likely occur when you have too many license files.
    Workaround: Remove some license files, move the license files to a shorter directory path or to combine license files into a single file.

  • License Setup wizard may not be able to start license server with many license files. During setup, it may lead to a situation where a command prompt window appears/disappears incessantly. This is due to the fact that License Setup wizard is not able to start lmgrd with a long command line and may get stuck in a loop.

    1. It is recommended to combine all license code words tied to same MAC ID into single license file to avoid setting large number of license files.
    2. Try to use a shorter path to place license files.
    3. If #1 and/or #2 does not help, start the license server (lmgrd.exe) from the command line (e.g. lmgrd.exe -c <lic-file-path> -l <license_server_log.txt>) and then set <PRODUCT>_LICENSE_FILE=<PORT-NUMBER>@localhost for product you want to use on same PC.
  • Dongle drivers for Flex-10 dongles on Linux are release specific. Installing the latest dongle drivers on Linux will function properly only for the most recent EEsof releases.
    : Install and use dongle drivers as needed.  If you need to run the most recent EEsof releases, use the latest  Flex-10 dongle driver. If you need to use older releases, uninstall the latest dongle driver and re-install the older dongle driver

  • FLO and EEsof License setup are writing server logs at different locations. However, the EEsof server log file location is updated in the License Manager > Environment tab.
  • When multiple same-named INCREMENT lines of different version exist on the license server, few advanced FlexNet options to reserve/limit licenses may not work properly. 
  • Product Selector “Check Availability“ generates incorrect results (which leads to license failure) for older releases when multiple date base versions of like-named bundles exist in the license pool.
  • In Linux, Product Selector OK and Cancel Buttons locations are reserved.
  • Starting from FlexNet Publisher 2015 (also known as version 11.13.1), the adoption of the best practice of the least-privilege security therein results in the License Server related Windows Service to run with the LocalService Account privilege (instead of the LocalSystem privilege as before.)  Running with the LocalService Account privilege, an executable can no longer access any files located in the per-user specific type of folders.  As a result, any license file placed in those folders can no longer be accessed by the License Server when the License Server is automatically started via the Windows Service upon each PC reboot. For the local node-locked license, this would not result in any disruption to the usage of EEsof applications; however, for the license installed on a network PC that is accessed by multiple client PCs, this may cause EEsof applications not to start after the network PC reboots
    Workaround: Store your license files in the Windows folders that are accessible by the LocalService Account privilege.  For example, C:\ProgramData or C:\users\public are both qualified choices.  In general, any folder that has the "Users" group listed in its Properties > Security page and this "Users" group has the read permission enabled should work. 
  • Using the default port to connect to a license server may cause a delay when checking out licenses. If no port is given in the license file, Flexera scans ports 27000 to 27009 to find the port. Starting from FlexNet Publisher 2015 (aka version 11.13.1), the default timeout for the response from each port increased from .1 seconds to 3 seconds.

    To avoid the delay, KSM now issues licenses with port 27009 instead of leaving this blank. The EEsof License Setup Wizard (from Licensing 2017.01 onwards) handles some common situations such as: where it detects license file(s) without port, when users get a new license file with port 27009, or when all license files for a vendor daemon does not have same port.

    You will not be able to start the license server if all license files for a vendor daemon on a server does not have same port.
    Users who manually setup a license server or using EEsof License Setup Wizard with older licensing bits may need to manually edit license files to comply with the following rules:

    1. All license files for a vendor daemon on a server must use the same port (or all be blank). 

    2. Using the default port (blank) is allowed but may result in longer checkout times. 

    3. If setting up a network server, select an unused port that is not blocked by a firewall.

    Workaround: If the user cannot change the port, or wants to use the default Flexera ports, the environment variable FLEXLM_TIMEOUT can be set to .2 seconds (200000), to minimize the performance degradation. However, if the network latency is an issue in your environment, you may need to fine-tune this setting to minimize the general performance degradation while still accommodating the network latency.

  • Installation of EESof EDA tools (such as, SystemVue 2016.08, Genesys 2017.XX, or ADS 2017.XX) may hang at 4% (percentage vary based on the products) for few hours or even more on some specific machines.
    • Disable Firewall setting in Anti-Virus Software installed on the PC.
    • Download and unzip process explorer from the below link and then invoke procexp.exe.
      Right click on the wusa.exe process under <Product installer exe> and select KillProcess. Now it will continue the product installation.
  • After installing EESof EDA tools (such as, SystemVue 2016.08, Genesys 2017.XX, or ADS 2017.XX) successfully and try to invoke the software or License wizard, you may encounter “api-ms-win-crt-runtime-l1-1-0.dll” missing error.
    Workaround: Install the Update for Universal C Runtime in Windows .  On Windows 64-bit system systems, the file to install is x64 version of the Microsoft hotfix KB2999226. A copy of the Windows6.1-KB2999226-x64.msu Microsoft 64-bit hotfix installer can be found under the C:\Program Files\Keysight\EEsof_License_Tools\bin directory.  The Microsoft hotfix KB2999226 can be found under the Update for Universal C Runtime in Windows  page at  https://support.microsoft.com/en-us/help/2999226/update-for-universal-c-runtime-in-windows as well.
  • On a newly formatted RHEL system, the EEsof Licensing tools may fail to boot. This is because the FlexNet Publisher 2015 requires a certain rpm
    Workaround: Under the EEsof product installation directory, there exists a utility script named "Linux_sys_check.sh" under the bin directory. Run this script to find out whether any rpm is missing; run this script with a "-y" command-line option to also have all the missing rpms automatically installed if you have the sudo or root privilege.
  • License server may stop recognizing Flex-10 dongle on some systems within a few hours after starting
    Workaround: If v6.10 or v6.11 is found and experience this problem then upgrade the WibuKey drivers to v6.30/6.30b from Wibu Systems.
  • Unable to install Flex-10 driver if Flex-9 dongle is already plugged into a machine
    Workaround: Before installing a Flex-10 driver for the first time, unplug the Flex-9 dongle.
  • There is a known FlexNet Publisher issue, whereby mixing node-locked codewords and floating codewords in one license file can result in: a) Remote simulations not working or b) A second local simulation not working in case the license is node-locked and also has incorrect version.
    Workaround: It is strongly recommended that you do not mix node-locked codewords and floating codewords in one license file nor in any configuration that ends up with node-locked codewords and floating codewords both available on the same server. In other words, put the node-locked license and the floating license on different servers, and point to the respective one based on what you need to run.
  • If a user simultaneously runs two instances of a product and has mixed different versions of the same codeword on one license server, extra licenses may be pulled and result in unexpected “Licensed number of users already reached for this feature” errors.
    Workaround: We recommend you remove expired codewords, to separate out the new and the old versions of codewords into different files and different servers, and to point to the respective one based on what you need to run.
  • Not specifying the TCP/IP port for the license server during license setup may lead to unexpected behavior and/or license checkout failure on the Windows platform. We strongly recommend you to always explicitly specify the TCP/IP port associated with each license server.
  • A node-locked and floating bundle operating on Linux cannot be shared between products using EDA License Tools version older than 2014.01 when run at the same time.
  • License Setup Wizard does not remove any previous user-configured FLEX Windows License Service manually set up by a user using FlexNet's lmtools.
    Workaround: You must remove the previous user-configured Windows License Service via lmtools.
    • Run the lmtools.exe from C:\Program Files\Agilent\EEsof_License_Tools\bin to invoke the lmtools utility. The lmtools utility window is displayed.

      If you have installed an EEsof product released before 1st August, 2014 on your system prior to installing an EEsof product released after 1st August, 2014 then the default EEsof Licensing tools path will remain C:\Program Files\Agilent\EEsof_License_Tools. On the systems that only have EEsof products released after 1st August, 2014 installed then the default EEsof Licensing tools path will be C:\Program Files\Keysight\EEsof_License_Tools.
    • In the Service/License File tab, check the Configuration using Services option. All user-configured FLEX Windows License Services will be listed.
    • Select the service you wish to remove.
    • Select the Config Services tab and click the Remove Service button to remove the service.
      To ensure that the license service or lmgrd is running, click View Log. A log window appears that confirms whether agileesofd and lmgrd are up and running.
  • While running multiple versions of prior ADS releases together, set ADS_MAXIMUM_BUNDLE_USAGE=ON in your environment so that all of them will use the same method to check out licenses. Otherwise, you might receive an error message, "Licensed number of users already reached".
  • On some Windows 7 machines, when more than one definition of an Ethernet adapter exists (duplicates), license checkouts may appear to hang up.
    Workaround: Disable the duplicate network card definitions in your network settings: Control Panel > Network and Internet > Network Connections. This issue has been acknowledged by Flexera and they have created a bug report (SIOC-000103097).
  • For LSF style distributed simulations, ensure that the PATH on the client computer points to the $HPEESOF_DIR/EEsof_License_Tools/${architecture} directory that corresponds to the EEsof release being used. This needs to be done in order to ensure that the proper version of the Flexera utilities (like lmutil ) gets picked up in the path before any older in-compatible versions (that may also be installed on a users’ system.)
  • License Setup Wizard ( aglmwizard.exe ), which is used to set up and record the license path would not work if you already have an environment variable set for ADS_LICENSE_FILE.
    Workaround: You can use ADS_LICENSE_FILE variable to point to license file or refer to Licensing (For Administrators).
  • The License Setup Wizard will exit or not properly configure a license server, if the server has all of its licenses currently in use.
    Workaround: Wait for a license on the server to become available as you normally would before launching the product.
  • Unable to set license in case unicode characters are used either in path or license file name because the Flex License Service does not support these characters.
  • The Product Selector tool will be unable to display the license server status properly when connected to older license server.
    Workaround: Upgrade your license server to the latest version.

  • EEsof Licensing Tools installer can hang on systems with McAfee LiveSafe installed and running the default firewall settings.
    Workaround:  Prior to installing EEsof Licensing Tools, temporarily turn off the McAfee LiveSafe firewall.

  • Licensing setup steps on systems with McAfee LiveSafe installed can fail.
    Workaround:  Under the McAfee LiveSafe firewall settings, under Port and Settings, allow the use of port 27001 for lmgrd.exe under the EEsof Licensing Tools installation bin directory.  Under Internet Connections for Programs , enable lmgrd.exe, aglmmgr.exe and aglmwizard.exe for all devices and turn off monitoring.

  • On Windows, EEsof product releases prior to 2014 can have boot time issues with licensing if an newer EEsof product is installed prior to installing the older product. For example, if a users installs Advanced Design System 2017 and then installs Advanced Design systems 2014.01, the user can have boot time errors with ADS 2014.01.
    Workaround:  For Advanced Design System users,  set a system environmental variable named ADS_LICENSE_FILE under the Control Panel/ System, and Security / System / Advanced system settings and under the "environmental variables".  Add an System variable named ADS_LICENESE_FILE and the value will be the path to your local license file or the port@host setting for your site.

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Third Party Applications

  • Spyder application menu bar becomes inactive when the window is maximized using View > Full Screen or by pressing F11 (shortcut key to maximize the screen).
    Workaround: Press F11 again to make it the default screen. The menu bar is now active and works fine.

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Virtual Test Bench

  • From VTB 2022, SystemVue VTB's QT help file is integrated into SystemVue VTB installer. However, help does not open, when you press F1 for a VTB component.
    Workaround: Perform the following steps:
    1. Open a command window.

    2. Set the path to ADS help directory. Execute the following command:

      On Windows

      set path="<ADS_Install_DIR>\bin\Help";%PATH%

      On Linux

      export PATH=<ADS_Install_DIR>/bin/Help:$PATH

      On RHEL 7 (due to library related issue)

      export HPEESOF_DIR=<ADS_Install_DIR>
      export LD_LIBRARY_PATH=$HPEESOF_DIR/lib/linux_x86_64:$HPEESOF_DIR/lib/linux_x86:$LD_LIBRARY_PATH
      export PATH=$HPEESOF_DIR/bin:$PATH
      export PATH=$HPEESOF_DIR/bin/HELP:$PATH


      <ADS_Install_DIR> is the ADS installation directory.

      On Windows: The default ADS location is "C:\Program Files\Keysight\ADS<version>"

      On Linux: The default ADS location is "/usr/local/ADS<version>".

      For example, <version> is 2022

    3. Invoke VTB help. Execute the following command:

      On Windows

      assistant -collectionfile "<VTB_Install_DIR>\Help\vtb.qhc"

      On Linux

      export SYSTEMVUE_INSTALLATION_DIRS=xxx/SystemVueVTB/2022
      assistant -collectionfile $SYSTEMVUE_INSTALLATION_DIRS/Help/vtb.qhc


      <VTB_Install_DIR> is the SystemVueVTB installation directory on Windows.
      xxx is the directory where unzip or untar of VTB package is done on Linux
      On Windows: The default VTB location is "C:\Program Files\Keysight\SystemVueVTB2022"

      You can also refer to the online version of the SystemVueVTB documentation.

  • When using VTB on Virtual Machine (VM), if SystemVue crashes then ensure to restart your system.

  • To use VTB, ensure ADS is installed in a path that has only ASCII characters.

  • Backward compatibility
    In ADS, the customized VTB can have a backward compatibility issue.
    Workaround: To fix this issue, use one of the following methods:
    1. Open and Save the custom VTB in SystemVue2022Update0.1. Now, you can use the custom VTB in ADS.
    2. A built-in workspace conversion tool is provided in the installer. You can convert the custom workspace (.wsv) to the newer SystemVue version. Use the following steps to convert the workspaces:
      • Open Command Prompt in the Administrator mode.
      • Browse the location of the old workspace. For example, C:\ADS_VTB.
      • Run the following command parameter.

        C:\ADS_VTB><SystemVueVTB_Installation_Dir>\bin\WorkspaceConversionToolManaged.exe" VTB_Examples.wsv VTB_examples_new.wsv


        1. <SystemVueVTB_Installation_Dir> is the location where SystemVue VTB package is installed. For example, C:\Program Files\Keysight\SystemVueVTB2022.

         2. VTB_Examples.wsv is old SystemVue file and VTB_examples_new.wsv is converted file.

    3. The following successful message is displayed.
      Created: VTB_example_new.wsv

    4. You can now use the VTB_examples_new.wsv workspace in ADS.

  • When multiple VTB versions are installed, the VTB package in the Library Configuration Editor remain fixed to a particular VTB version. However, symbol view uses the correct VTB version.

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Examples - Known Issues

  • Examples under <ADS Install Directory>\examples \Instrument_links folder are not getting opened on Linux where as they are opening fine on Windows.
    Workaround: Rename the ‘Instrument_links’ folder to ‘Instrument_Links’, if you have write permission to the <ADS Install Location>\examples folder. In case you do not have the write permission then proceed with manual unarchive process (File > Unarchive from the ADS Main window) pointing to the Example workspace. 

  • Example search might not work and prompt you the "Database is locked" error when ADS installation is on NAS.
    Workaround: Restart the nfslock service on client. In case the problem still persists, reboot the client to unlock the database.

  • Unable to compile Pin Diode Model using Visual Studio 2012 on Windows 7 64-bit platform.
    Workaround: Delete the contents of the directory examples\RF_Microwave\UserCompiledModel_wrk\ UserCompiledModel\lib.win32_64 before using UCMs.
  • An error occurs while running a custom VTB.
    Workaround: Download and run a custom VTB from the following location: <ADS Install Location>\SystemVue\2016.08\win32_64\VTB.  

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  • On Windows, Printing directly from installed help generates non-readable output.
    Workaround: Use PDF version of the document for printing purpose.

  • From ADS 2016.01 onwards, in ADS help when you open a page using the "Open a link in new tab" option the help does not open a page in a different tab by default. You need to set the preferences to open any link in a new tab.
    To set the preferences:

    1. From the ADS 20xx (or the installed version) Help, Click File > Edit > Preferences.
      The Preferences Dialog box is displayed.

    2. Select the Options tab.

    3. Under Appearance, select the Show tabs for each individual page option.

    This is a one-time setting for a particular release of a product.
  • Unable to open online help, any external link, or Embedded Survey link in Linux on Mozilla Firefox browser.
    Workaround: Use Mozilla Firefox version 39 or above or keep the Mozilla Firefox window open and then try to open online help.
  • While using the installed ADS help, you may encounter issues like help not showing any content, it throws an error, it displays unexpected hierarchy in the Content tab, or it does not display any search results.
    Workaround: Close the help, delete the contents of the following directory, and open the help again. 
    • On Windows:  C:\Users\<Windows_Login_ID>\AppData\Local\Keysight\Help
    • On Linux:
      •  $HOME/.local/share/Keysight/Help
      • $HOME/.cache/Keysight/ADS/2021
  • ADS installed help search does not support [] or {} or any other text using these combinations.
  • On Linux, Konqueror web-browser does not display the online help properly. It may not display help pages at all or may display them broken and with errors. 
    Workaround: Use Mozilla Firefox to view the online help.

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