4 Replies Latest reply on May 22, 2018 11:26 AM by weston_beal

    Significance of DDR3 Batch Simulation

    ather

      Hello all,

      I am a newbie to Hyperlynx tool and I had to simulate Alliance Memory's DDR3L RAM(1600 Datarate) with NXP's PowerPC processor T1042. I was trying to simulate individual signal separately and then I came to know that Hyperlynx also had DDR3 batch simulation option.
      In my design there are two ranks of memory(4 chips + ECC per rank). I am using x16 Memory chip.

       

      My question is , what is the significance of ddr3 batch simulation over individual signal simulation? And where can I find helping material to setup batch simulation?

      Regards

      Ather

        • 1. Re: Significance of DDR3 Batch Simulation
          cgoldenbus

          Ather,

          Is this a pre or post layout simulation?

          I've only done post layout sim and then work backwards to address timing, margin or S.I. issues like overshoot etc..

          I always had my design rules, Stackup's and impedance's defined and then simulated at the end end of my layout.

           

          I guess you could add all of your driver/receiver pairs individually and simulate the whole data bus for a number of clocks or stimuli but that seems but that seems way too involved at least for me.

          For me working it backwards was easier because the DDRX wizard ran the whole simulation from the board and then reported to me all of the required data plus my pass fail .. if something was amiss I could always push from the layout back to linesim and make theoretical adjustments to correct and then correct my layout and re-run.


          This at least would allow you to run both read and write analysis on your entire chain using your ODT's etc.

           

           

          There was a a great webinar on running sweeps of the terminations it may still be out there then maybe it will give you an idea for  setting up other batch functions.

          • 2. Re: Significance of DDR3 Batch Simulation
            cathy_terwedow

            Are you talking about one of these videos?

            http://bit.ly/2wx2jnT - 3 mins video

            http://bit.ly/analyze-DDR - 18 mins webinar

            • 3. Re: Significance of DDR3 Batch Simulation
              cgoldenbus

              Cathy,
              Unfortunately no, I think I mis-spoke, It was a webinar on running sweeps in the DDR simulation.
              It was a bout a year ago.. I'd have to dig through my emails and see if I had the link to the webinar.. maybe it was recorded?

              • 4. Re: Significance of DDR3 Batch Simulation
                weston_beal

                Muhammad,

                 

                The advantage of running the DDR Wizard is a lot of automation and additional checks. After you specify some configuration data to the DDR wizard, it automatically simulates many transitions on each net in your DDR bus and then runs various SI and timing checks on the simulation results. The final report gives you a pass or fail status of each net in the bus. What the wizard does in an hour would take a person many days or weeks to do manually.

                 

                The BoardSim User Guide has a good section on setting up the DDR wizard. There is also a lot of useful information regarding DDR simulations on Support Center.

                 

                Regards,

                Weston