[ibis-macro] Minutes from the 7 May 2013 ibis-atm meeting
- From: Mike LaBonte <mike@xxxxxxxxxxx>
- To: IBIS-ATM <ibis-macro@xxxxxxxxxxxxx>
- Date: Thu, 9 May 2013 13:29:48 -0400
Minutes from the 7 May 2013 ibis-atm meeting are attached.
Mike
IBIS Macromodel Task Group
Meeting date: 07 May 2013
Members (asterisk for those attending):
Agilent: * Fangyi Rao
* Radek Biernacki
Altera: * David Banas
Julia Liu
Hazlina Ramly
Andrew Joy Consulting: Andy Joy
ANSYS: Samuel Mertens
* Dan Dvorscak
* Curtis Clark
Steve Pytel
Luis Armenta
Arrow Electronics: Ian Dodd
Cadence Design Systems: Terry Jernberg
* Ambrish Varma
Feras Al-Hawari
Brad Brim
Kumar Keshavan
Ken Willis
Cavium Networks: Johann Nittmann
Celsionix: Kellee Crisafulli
Cisco Systems: Ashwin Vasudevan
Syed Huq
Ericsson: Anders Ekholm
IBM: Greg Edlund
Intel: Michael Mirmak
Maxim Integrated Products: Mahbubul Bari
Hassan Raghat
Ron Olisar
Mentor Graphics: John Angulo
Zhen Mu
* Arpad Muranyi
Vladimir Dmitriev-Zdorov
Micron Technology: * Randy Wolff
Justin Butterfield
NetLogic Microsystems: Ryan Couts
Nokia-Siemens Networks: Eckhard Lenski
QLogic Corp. James Zhou
SiSoft: * Walter Katz
* Todd Westerhoff
Doug Burns
* Mike LaBonte
Snowbush IP: Marcus Van Ierssel
ST Micro: Syed Sadeghi
Teraspeed Consulting Group: Scott McMorrow
* Bob Ross
TI: Casey Morrison
Alfred Chong
Vitesse Semiconductor: Eric Sweetman
Xilinx: Mustansir Fanaswalla
Ray Anderson
The meeting was led by Arpad Muranyi
------------------------------------------------------------------------
Opens:
- Walter: Hope to discuss my email today
--------------------------
Call for patent disclosure:
- None
-------------
Review of ARs:
- Walter working on clearer flow document for Redrivers.
- Walter to write new BIRD for [Repeater/Retimer Pin] keywords.
- in progress
-------------
New Discussion:
No interconnect Task group report
PI & SI simulations with legacy IBIS model
- Arpad: Has draft 8 of Walter's BIRD been posted?
- Walter: No
- Walter: Power voltage far from that used for model derivation
will cause inaccuracies
- Arpad: The IBIS Data Derivation section does not require simulation at Pullup
reference voltage
- Walter: For legacy IBIS models, yes
- For [External Model] no assumption can be made about how to handle other
voltages
- Arpad: It is not true that voltage should be between min and max, for example
- We might need some editorial cleanup
- Walter motioned to send this issue to the editorial committee
- Bob seconded the motion
- No one opposed
BIRD 156 IBIS-AMI Extension for Mid-Channel Redriver
- Arpad showed the email from Walter, which has 3 bullets:
- 1) Only discusses TD simulation
- Walter: Need to discuss this with Fangyi
- Todd: We need to see how it fits with 10.2.1. and 10.2.2 in the existing
spec
- Fangyi: We assume the EDA tool can figure out statistical once the TD
flow is known
- I can add that to the BIRD
- Bob: There is a different flow for redriver
- Fangyi: The only difference is constructing the impulse response
- Walter: The IBIS 5.1 flow is used for each channel, upstream and
downstream
- The only question is the waveform given to the redriver TX
- Ambrish: The stimulus is different
- 2) Combinations of Init_Returns_Impulse and GetWave_Exists
- Walter: The primary TX gets digital stimulus
- The redriver TX gets a different stimulus
- Fangyi: The redriver TX is not event driven
- Arpad: Does the BIRD describe this?
- Fangyi: Yes
- Arpad showed BIRD 156
- Bob: The terms "upstream" and "downstream" should be defined
- Mike: Numbers should be used, there can be more than two
- Radek: The BIRD introduction makes it clear
- Arpad: That will not go into the spec
- Bob: This needs to describe output and input impedances
- Fangyi: That is described (Arpad highlighted)
- Bob: That was not an assumption for all AMI models
- Walter: Between each TX and RX is an analog channel
- Between each RX and TX is an algorithmic channel
- Every analog channel is analyzed the same way
- The issue is how to analyze the RX to TX channels
- If RX has no GetWave, how to generate waveform for TX?
- Ambrish: IBIS 5.1 describes this
- You convolve the stimulus with the impulse response
- Fangyi: For this diagram it doesn't matter if GetWave is used
- Arpad: If the left channel has no GetWave the output will have to be
convolved to get the second TX input
- This will have to be specified
- Todd: The only valid statistical flow is when they all have Init
- It's not hard to figure out, but it has to be specified
- Arpad: This is bringing back Use_Init_Output
- Todd: SiSoft never agreed with Use_Init_Output
- Fangyi: We should not have to get into this now
- Todd: What needs to be done is not said
- Fangyi: It is in step 7
- Todd: I'm not sure that works, this is RX to TX
- Fangyi: It is always RX to TX
- Walter: We should not have to debate that it works, we just need to
specify it
- Ambrish: We have been doing it
- Todd: We probably are all doing the same thing, but it is not specified
- Walter suggested a sentence that would specify what is needed
- Fangyi: That is what step 8 says
- Todd: Most likely the RX is GetWave only and the TX is Init only
- How is that handled?
- Fangyi: Follow step 8
- Arpad: We still need to describe how the left channel connects to the
right
- Todd: What if the RX does not have GetWave?
- Fangyi: It still has an output waveform
- Todd: Step 8 says "output waveform of the redriver's input algorithmic
model"
- Arpad: Init has no waveform
- Ambrish: It is the waveform maintained by the simulator, the channel
waveform
- Walter: No cases require deconvolution, we should be able to describe all
cases
- We only need to describe the redriver RX to TX path flow
- Ambrish: We should refer to channels by number
- Arpad: An Init only TX can only receive an impulse response, not a
waveform
- Walter: On page 2 a word "output" should be "input"
- Fangyi: Agree
- 3) Jitter and Noise
- Walter: We should not prohibit noise modeling in redrivers
- Fangyi: How can you add jitter to an analog waveform?
- Todd: It will be handled elsewhere
- Walter: It says GetWave handles noise, but Gaussian can't be handled there
- Todd: We mostly suggest not precluding it here, from a standards viewpoint
- Dropping the paragraph would do it
- Fangyi: We will look at that
AR: Fangyi update BIRD 156 per task group feedback
-------------
Next meeting: 14 May 2013 12:00pm PT
-------------
IBIS Interconnect SPICE Wish List:
1) Simulator directives
Other related posts:
- » [ibis-macro] Minutes from the 7 May 2013 ibis-atm meeting - Mike LaBonte
