DDR and AMS Simulation in the PADS Professional Premium flow

By Shivani Joshi

Analysis at every step of the design process has become essential in producing quality boards with less rerun time and cost. With HyperLynx Signal Integrity in the PADS Professional Premium flow, analysis can be done quickly and simply. Let’s take a deeper look at DDR and AMS design analysis.

Streamline your DDR designs with PADS Professional Premium and HyperLynx DDR

DDR interfaces are some of the most complicated parallel interfaces in use today. A complete validation of DDR interface requires hundreds of signal integrity simulations and thousands of detailed measurements, then followed up by a comprehensive analysis of all the signal quality requirements and signal and group timing relationships.

Traditional signal integrity batch tools just aren’t up to the task, however, with HyperLynx in the PADS Professional Premium Flow, you can streamline your DDR designs by dramatically reducing simulation setup time while providing accurate, detailed results – including the effects of velocity transmission lines, reflections, impedance changes, via crosstalk, via to via coupling, and timing delays.

Fast track design decisions and improve engineering efficiency

With HyperLynx DDR, you can fast track design decisions and improve engineering efficiency, all while accelerating your time to market. The intuitive DDR Wizard will interactively walk an engineer through a series of setup questions. So, you could be a pro or you could be completely new to DDR designs, and the wizard will help you set up the parameters for use in signal integrity and timing simulations. Users are guided by a step by step process of selecting their IBIS models for controller and memory devices, specifying their driver strength and on-die-termination (ODT) settings for read and write cycles, and defining byte-lane, strobe, or mask assignments.

The wizard also allows for users to save their templates and all their settings to be recalled for future use, therefore saving even more time on future projects. Once your simulations have completed, HyperLynx DDR produces a report with details on passing and failing combinations. Eye density plots are quickly accessible to further design assessment. All sweep data is also saved and can be loaded into an oscilloscope view for a more detailed comparison.

Ensure the intended behavior of your design circuitry and eliminate costly performance issues by simulating designs early on

In PADS Professional Premium, users are able to simulate real world circuit behavior to solve today’s circuit design challenges with built-in analog mixed signal simulation. Starting at the schematic stage, users can simulate schematic designs using both Spice and VHDL AMS models. Having both of these options available allows for greater flexibility in verifying complex electrical systems. The AMS simulation toolbar in PADS Professional Premium can launch a symbol search and place window with a large selection of Spice and VHDL AMS symbols in its library. Assign models and investigate properties with a simple click of objects to address design requirements and customize values or properties as needed.

AMS simulation in PADS Professional Premium even has a built-in waveform calculator option to aid in analysis. Run a time domain simulation with fast fourier transform enabled and review your output to help make essential design changes. Ensure output ripple voltage falls into design specs by selecting the intended calculation and the tools will properly determine your values automatically. With so much to investigate and calculate, you can streamline AMS designs with ease.

Using PADS Professional Premium’s HyperLynx options like DDR and AMS can advance your PCB flow. Utilizing HyperLynx in your PADS Professional Premium flow lets you evaluate alternatives to optimizing for cost and performance while ensuring the design meets stringent signal integrity and timing requirements.

Watch this 20 minute on-demand webinar to learn more about PCB signal integrity in the PADS Professional Premium flow

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This article first appeared on the Siemens Digital Industries Software blog at