I've inserted some comments below, and have attached a revised
version with the Ad Hoc acronym updates.
On 6/23/2014 6:06 PM, Darshan, Yair
Ken: Yes. (Addressed in the revised slides.)
see my comments. I'll appreciate if you can address it prior
the meeting so we can save time.
Slide 2: Please
use the ad-hoc Acronyms as agreed on Annex J1 page 60 at the
ad-hoc material. I am referring to bullet 2 when you say
"P2PRunb". Do you mean End to End P2PRunb ?
Ken: I understand that End-to-End P2PRunb is
not intended to be a specification in the standard
The End to End
P2PRUnb is system requirement that will generate eventually
the current unbalance in addition to voltage unbalance PSE
and PD. This parameter will not be in the spec. It is a
guide line or "system" spec to us.
Ken: The point of the presentation is that PSE
PI P2PRunb is not the best method. The derived equation
accurately describes PI contribution to End-to-End
P2PRunb, whereas PI P2PRunb does not.
that will be specified are:
Resistance and voltage unbalance.
Resistance and voltage unbalance.
Ken: Adding a minimum resistance does reduce
worst case End-to-End P2PRunb, however the inequality still
Slide 3: No
comments. It is correct. Furthermore I am going to propose
to specify minimum resistance to PSE PI and PD PI per my
presentation conclusions sent to the reflector and to the
team regarding the channel use case analysis results. This
is I believe supported and resolve the last two bullets in
Ken: I used the resistances in the
End-to-End P2PRunb equation and solved for Rpse_max. (Kxx factors
were not considered but may be accounted for in the answer,
depending upon how they are defined.)
Slide 4: I like
the direction. It supports slide 3. It is also similar to
the analytical way that I have shown in the last adhoc
meeting (on slide 14 of our next meeting material) which is:
that the Kpd part and Kch part was merged to Y term. Is this
Ken: Will address in the meeting.
Slide 5. Looks
good. Please show equation derivation to justify the method.
It will helps also to those who interested to use it and run
simulations to test the concept.
Ken: If there is a balancing mechanism, such
as active balancing, where simple Resistance and Voltage
measurements don't describe the circuit behavior, or even fail
based upon such behavior, then a resistance and Voltage
requirement and test is not appropriate.
bullet not clear. (Don’t
otherwise provide a balancing technique)
Ken: Any source has an internal resistance; if
more than one port exists on the PSE, then sourcing to other ports
will cause a Voltage difference that is not present in a
compliance test. I suppose a single-port PSE designed with two
power supplies could be an exception.
bullet: Why "4 pair powering shall be sourced from a single
DC supply" is Important if Voltage difference is specified?
Ken: It would decrease non-linearity with
respect to PI unbalance. If not a requirement, it could be a
recommendation, along with recommending matched diodes in a PD.
Bullet 6: It
is implementation issue. We cannot require it. You need to
translate your intention to voltage, resistance, current to
allow/disallow what you believe is best and we can discuss
Ken: I don't have time to do this prior to the
meeting... I'm also not clear on which numbers to use.
Yes agree. I am proposing the same for PSE and PD i.e. to
derivation of equations: Please supply next meeting
calculated examples so we can verify in simulation. Please
use only adhoc numbers so we can use the same data base and
Christiam and me can both check it.
Ken: This slide is only an example
demonstrating the fact that PI Runbalance is not equal to PI
Runbalance contribution to End-to-End P2PRunb. The derived
equations cover this ok, so there's no need to discuss it.
Example at the
last slide: The point is clear. Please use the adhoc data
base from the same reasons above.
Hi Yair, All,
I've attached a new revision of the slides for the meeting.
On 6/22/2014 8:03 PM, Darshan, Yair
Please find meeting material for Tuesday
June 24, 2014. The focus is planned to be on slides 6-10,
I'll appreciate if you review the slides
per the agenda prior the meeting.
Ken: You are scheduled to present your
material from last time. Please resend it to the
over HDBaseT Subcommittee
Mixed Signal Group
Hanagar St., P.O. Box 7220
Ne'eman Industrial Zone
Hod Hasharon 45421, Israel
Tel: +972-9-775-5100, EXT 210.