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2017

Signal and Power Integrity engineers look to ADS for the correct treatment of high-speed effects like distortion, mismatch, and cross-talk. Building on the strong foundation and loyal users ADS has amassed through the years, ADS 2017 delivers new options and functionality that enable it to be the tool today's designers need to get ahead.

 

The latest release of ADS is a stronger, faster, and more comprehensive platform for signal and power integrity analysis. Read about the top 10 new features in ADS 2017 for Signal and Power Integrity Engineers or watch the video.


 

10. Improved substrate editor

The new and improved substrate editor has an efficient edit feature for a larger number of layers. The simplified editor interface reduces simulation setup time and increases productivity.

ads2017 substrate editor

9. Fast Wire labeling

Labeling ports with the correct node names is time consuming, especially when you have many ports. With the new CSV import labeling, naming more than 10 ports is simple. 

ads2017 fast wire labeling

 

8. Parallel Sweep on windows

In ADS 2017, Batch simulation is able to run in Turbo mode in both Linux and windows. Using the 8-pack Element license and simulation manager, you can unleash the parallel computing power of your workstation PC. Reduce simulation time of large sweeps with simulation manager.

ads2017 parallel sweep

 

7. Statistical mode PAM -4

To simulate a PAM-4 signal down to 10 ^ -16 BER, a bit-by-bit simulation would take hours. ADS 2017 now supports PAM-4 in statistical mode. You can directly simulate PAM-4 to very low BER in a matter of seconds to minutes.

 

6. Mixed-mode S-parameter Checker

In the improved S-parameter checker, you can now convert single-ended S-parameters to mixed-mode in a few clicks. Save time and increase your productivity by letting the S-parameter checker show you the mixed-mode response.

ads2017 mixed mode s-param checker

 

5. S-parameter Spectral Thresholding

Usually, you would expect simulation speed to decrease with higher port count. In ADS 2017, the spectral thresholding algorithm removes weakly coupled ports before simulation. The result is faster simulation speed for a higher port count, without sacrificing accuracy.

ads2017 faster simulation

 

4. New and improved IBIS Components

Are you looking for specific pins in your IBIS model to interact with? The improved IBIS component interface helps you quickly sort and select desired pins. With built-in smart default settings, the IBIS schematic is cleaner, and setup time is faster.
ibis components

 

3. 3D Via Designer: Enabling Access to Accurate Via Models

A crucial problem when simulating high-speed signal interconnects is a lack of access to via models that are accurate at high frequencies. To solve this problem, ADS 2017 introduces Via Designer, a tool for creating and modeling PCB vias (single-ended or differential), while giving you full control over the via specifics.
ads2017 3d via designer

 

2. PIPro Bill of Materials Optimization for Decaps

Decap Optimization in PIPro can take all the decaps as laid out on the board, and search for the optimal solution that meets the desired target impedance profile. The user can define an optimal solution, by specifying weighted criteria such as: number of decaps, unique models, vendors, or cost. PIPro's algorithm intelligently ranks your best candidate solutions so you arrive at the best trade-off between performance and cost.

decap output

 

1. PIPro DC Electro-Thermal Capability

To find the true IR-drop of your power distribution network, thermal effects need to be considered in your analysis. PIPro performs an automated, iterative electric and thermal solve on each PDN, providing thermal insights to every power integrity engineer. PIPro calculates the temperature distribution of the board, so you can ensure the temperatures of vias, traces, and devices in your design are within the specification.  

ads2017 electro-thermal

 

 

These 10 new features are just the beginning of all the new capabilities and usability enhancements in the latest release of Advanced Design System (ADS) 2017. Along with improvements for the Signal and Power Integrity Designers are improvements for RF/MW designers doing RF front-end module and Silicon RFIC design. Check out all the new features on the web page and apply for your free trial of ADS 2017 today.

free trial of ADS 2017

FREE Evaluation of ADS | Keysight EEsof EDA  

Many of you know Matt Ozalas, RF Design Engineer at Keysight Technologies, and his infamous YouTube video series, How to Design an RF Power Amplifier. I got a chance to talk to him about what he’s most excited about in the latest ADS release.

Matt Ozalas, RF Design Engineer at Keysight Technologies

 

Kaelly: I heard ADS 2017 is being called the “3D release”. What 3D capabilities are you excited for?

 

Matt: It’s 2017, we’ve got hoverboards and self-driving cars -- we should be designing in 3D by now, right?  Besides the “wow” factor, some tasks are really useful to do in 3D.  I think a lot of designers will feel the same way after trying the new capabilities in ADS 2017 out.  In ADS 2017, those 3D capabilities span design, simulation, and visualization.   So, physical design becomes more realistic early on, the simulation is easier to set up, the results are more accurate, and the analysis becomes more meaningful. 

 3D layout, ADS 2017

In ADS 2017, you can design a layout in three dimensions. You can route a trace or stitch a VIA more precisely in a dense module or chip, and you can select complex structures much more easily in 3D.  This might seem trivial but we’ve all been in that spot where a VIA gets missed or the routing goes to the wrong layer and that causes big problems down the line. Designing in 3D prevents these mistakes from the outset.  The 3D selection also helps if you’re trying to do an EM simulation, getting all the right structures selected is not always easy.  You can even thermally simulate multiple technologies at the same time, like a chip stacked on a substrate.  Let’s face it, no one can afford to overlook these things in the design process anymore, mistakes cost too much and reliability problems are too critical to leave to chance.  Just ask those people making hoverboards.

 RFIC layout, ADS 2017

Kaelly: Designers are always looking for ways to save time. Is ADS 2017 faster than its previous release?

 

Matt: Yes, let’s look at EM simulation for example.  The Momentum 3D planar EM simulator now uses multi-threading for substrate calculations in ADS 2017.  What does that mean?  Well, typically substrate calculations only use one processor, but for example, your Windows machine probably has four processors.   In ADS 2017, Momentum farms those calculations out to the different processors and so on that Windows machine, you will see a 4x speed improvement in the substrate calculation.   By the way, in Momentum, the substrate calculation is usually the most time-consuming piece.  Now, what about 3D Finite Element Method (FEM) Simulation?  Well, in ADS 2017, this 3D engine has a turbo mode which distributes the simulation frequencies to different processors, and that of course, speeds up the simulation time dramatically.   

 FEM in ADS 2017, finite element method

Kaelly: I know there are many usability improvements in ADS 2017. Which ones are most exciting to you?

 

Matt: The way I look at it, no matter how good a capability is, if it isn’t easy to use, I probably won’t use it.  So 3DEM simulation is faster, right?  Great, but what about getting your design into that EM engine?  If that takes too long, all the speed improvement is less meaningful.   In ADS 2017, we looked closely at the EM setup process, like what steps designers take before they run an EM simulation.  They set up a substrate, then perhaps if they want to analyze a sub design, they’ll cut that part out, remove unwanted metal, add ports, go play around with some EM settings, and finally click run.   A lot of steps. 

3D EM in ADS 2017

 

In ADS 2017, you will find that every one of those steps is easier.  The substrate editor has a table definition feature which enables you to easily create and modify highly complicated substrates with lots of layers.  A grouping capability allows you to much more easily group items you want to be modeled. There are even features that allow you to more easily place multiple ports and pins, and assemble and define ports. Separately, these features might not seem all that exciting, but put them together and the result is undeniable: fast and simple EM simulation setup.

 

Anyone who has ever used the ADS Electro-Thermal simulator knows that defining a substrate involves a text-based file, but not anymore. With ADS 2017, you can accomplish that task using the substrate editor. Just imagine how much easier it will be to visualize your thermal stackup using the substrate editor, rather than writing it into a cryptic text file.

 

Another great new feature in ADS 2017 is its multi-technology support (e.g., Chip on Package). In the past, if you had a chip that went into a board or module, you then had to simulate those two technologies. You could do it, for sure, with the ADS Electro-Thermal simulator, but it required a 3-page procedure and was impossibly difficult. With ADS 2017, that simulation of multiple technologies just works.

 

Kaelly: What’s the ADS Python Data Link that I keep hearing about?

 

Matt: I have been using this capability for all kinds of neat things. This is what I’m most excited about in ADS 2017. In essence, you can take your ADS simulation result and run it through a Python script by just using an equation in data display. The ADS data goes into Python, the script gets run, and the results come back to ADS in one step.  It’s like hooking a rocket engine onto ADS Data Display – and the best part is you never have to leave the simulation environment.  The possibilities are endless: 3D plotting, instrument connectivity, loadpull contours from measured data, all that stuff becomes easy to do, and you don’t even need to know Python to take advantage of it because the scripts already exist and they just run in the background.  The best application I’ve seen of this feature so far is plotting ADS simulation data on a cylindrical 3D Smith Chart, called the “Smith Tube”.  Look up the Smith Tube on IEEE Explore, it is so cool.  It will change the way you think about circuit design – seriously!

 ADS 2017 Data Link with Python

Kaelly: Thanks Matt! I’ll have to check that out.

 

If you want specific information on any of the features Matt mentions, and some that he didn’t, check out the ADS 2017 release webpage.

 

free trial of ADS 2017

FREE Evaluation of ADS | Keysight EEsof EDA  

LTspice

 

LTspice is a freeware SPICE simulator offered by Linear Technologies (now a division of Analog Devices Inc.). LTspice was originally called “SwitcherCAD” and was designed with switch-mode power supplies in mind. As a result, it is widely used in power electronics. IC-CAP may be used to generate device models based on measured data using multiple simulators: not only our own ADS Transient and Harmonic Balance (for periodic state state) simulators, but also transient analysis in LTspice, giving engineers the option to create workflows as needed.  For an engineer that might want to generate a model based on measured data using LTspice as the simulation engine, here's a look at how you do that.

Flow diagram, showing LTspice to IC-CAP link

 

But before delving into the details of that process, it's worth noting that as of this writing, the LTspice documentation describes support for seven different MOSFET device models:

 

LevelModel
1Shichman-Hodges
2MOS2 (A. Vladimirescu and S. Liu, October 1980)
3MOS3, a semi-empirical model
4BSIM (B. J. Sheu, D. L. Scharfetter, and P. K. Ko, May 1985)
5BSIM2 (Min-Chie Jeng, October 1990)
6MOS6 (T. Sakurai and A. R. Newton, March 1990)
8BSIM3v3.3.0 from University of California, Berkeley, July 29, 2005
9BSIMSOI3.2 (Silicon on insulator) from the BSIM Research Group, February 2004.
12EKV 2.6 (M. Bucher, C. Lallement, F. Theodoloz, C. Enz, F. Krummenacher, June 1997.)
14BSIM4.6.1 from the BSIM Research Group, May 18, 2007.
73HiSIMHV version 1.2 from the Hiroshima University and STARC.

How to Link IC-CAP to LTspice

If you have no background on how to link IC-CAP to an external simulator, I recommend you read my previous post
entitled, “Link the IC-CAP Modeling Tool to External Simulators.” It will provide you with an overview of the basic process, along with some troubleshooting tips.

 

LTspice is not officially supported by IC-CAP. However, we have a workaround to successfully link IC-CAP to LTspice IV by disguising it as a SPICE3 look-alike. To date, this workaround has not yet been tried on LTspice XVII.

 

Assuming you have LTspice installed on your system, here are the steps:

  1. Append the following line into your $ICCAP_ROOT/iccap/lib/usersimulators file.

    ltspice spice3 $ICCAP_ROOT\src\ltspice3.bat "" CANNOT_PIPE

    We used spice3 as the template_name, so that IC-CAP will treat the simulation input/output files as if it were for SPICE3, which is natively supported.

  2. Download the ltspice3.bat file from the attachment below.

    Note, the file was renamed to ltspice3.txt for security concerns. After you download it, please rename it back to ltspice3.bat.

    Open and edit ltspice3.bat on line 30. Make sure it reflects the correct path to the LTSpice IV executable scad3.exe, as shown below:

  3. Move the ltspice3.bat file to directory $ICCAP_ROOT/src.

  4. Restart IC-CAP.

Verify the Simulation Link to LTspice IV

 

Now, let’s verify that it works, to ensure we can indeed use LTspice as the simulator engine for IC-CAP model parameter extraction. To do that:

  1. Load the following *.mdl example file from within the IC-CAP program:../Examples/model_files/mosfet/nmos3.mdl
  2. In the model Variables, add the variable SIMULATOR and set it to ltspice.

    Image

  3. Go to the /large/idvg/ setup, and clear out the simulated data using Clear -> Simulated. Any previously saved simulation will be gone.

    Image

    We now see only the measured data (symbols) on the plot, whereas simulation data would be shown as solid:
  4. Simulate.

    Image

  5. In the same DUT/Setup, open the plot tab under the /large/idvg/idvsvg plot, and confirm that the simulated data appears.

    Image

The simulated data is represented by solid lines on the plot.

 

So there you have it! By following this process, you can now use LTspice as your simulator for model parameter extraction within IC-CAP.