Arpad,
SerDes thresholds are always at the decision point.
Walter
Sent from my Android phone using TouchDown (www.nitrodesk.com)
-----Original Message-----
From: Muranyi, Arpad [Arpad_Muranyi@xxxxxxxxxx]
Received: Friday, 03 Apr 2015, 4:25PM
To: IBIS-ATM [ibis-macro@xxxxxxxxxxxxx]
Subject: [ibis-macro] Re: Updated PAM4 BIRD rev 5
Ambrish,
I thought that the "decision point" is at the core logic input,
i.e. after the Rx and all of its signal processing bells and
whistles, while these thresholds are on the input side (pad) of
the Rx... Or am I missing something?
Thanks,
Arpad
=================================================================
From: ibis-macro-bounce@xxxxxxxxxxxxx [mailto:ibis-macro-bounce@xxxxxxxxxxxxx]
On Behalf Of Ambrish Varma
Sent: Friday, April 03, 2015 4:22 PM
To: wkatz@xxxxxxxxxx; IBIS-ATM
Subject: [ibis-macro] Re: Updated PAM4 BIRD rev 5
Hello Walter,
I have a quick question on the threshold parameters 'PAM4_UpperThreshold,
PAM4_CenterThreshold, PAM4_LowerThreshold':
If these parameters are not present, can't the EDA tool get the threshold
values from the waveform at the Rx decision point?
Why should the EDA tool be "expected to use the following values:
PAM4_UpperThreshold = 0.333
PAM4_CenterThreshold = 0.0
PAM4_Lower_Thresholf = -0.333" ?
There is a good chance that the waveform at the Rx decision point will be
distorted due to ISI and if the threshold parameters are absent, the EDA tool's
expectation of 0.333, 0 and -0.333 will be off.
If the parameters are absent, the EDA tool should be able to come up with the
threshold values.
Thanks.
Ambrish.
From: ibis-macro-bounce@xxxxxxxxxxxxx<mailto:ibis-macro-bounce@xxxxxxxxxxxxx>
[mailto:ibis-macro-bounce@xxxxxxxxxxxxx] On Behalf Of Walter Katz
Sent: Tuesday, March 31, 2015 4:31 PM
To: IBIS-ATM
Subject: [ibis-macro] Updated PAM4 BIRD rev 5
All,
I am enclosing an update PAM4 BIRD (now at rev5). Please review carefully. I
plan on submitting this formally to the IBIS Open Forum meeting on April 10.
Walter
Walter Katz
wkatz@xxxxxxxxxx<mailto:wkatz@xxxxxxxxxx>
Phone 303.449-2308
Mobile 303.335-6156
