[8023-POEP] IEEE 802.3at Vport ad hoc meeting Nov. 9, 9 AM

["Fred Schindler (frs)" <frs@xxxxxxxxx>]

Hello,

 

The Vport ad hoc has the following meeting schedule to discuss the dynamic port voltage requirements.  This meeting will be used to review data and constraints, and develop new constrains for the proposed IEEE 802.3at standard.

 

This effort would benefit from additional data on PSE transient response and PD di/dt demands (Please see the previous presentation for how these are characterized.).

 

Thursday November 9, 9 AM (PST)

Telephone number: 888-525-6064 , 408-525-6064

Meeting ID: 802328 (8023at)

Duration: 60 minutes

 

Thanks,

 

Fred Schindler

Technical Leader

CISCO Systems

170 West Tasman Drive

M/S SJ-19-3

San Jose, CA 95134-1706

Tel. (408) 525-9859

 

-------------------- Information from our last meeting  ---------------

…

5)      Items to collect data on: (everyone is encouraged to collect this information)

a.       PD di/dt values for

        i.      Shipping systems.

        ii.      Front-ends of PD with maximum load step.
       PD loads may not be well controlled but the DC-DC and front-end of the PD will filter the demand to produce the PD di/dt.  Silicon vendor application guidelines will help determine di/dt possible.

         iii.      When PSE changes from 57V to 44V through a representative channel resistance.

b.      Topologies of DC-DC suitable for PDs.  Identify the worst-case topology for additional analysis.

c.       AC-DC di/dt demand possible (data points) while still within specification.
Use the system constraints (ex/ supply tolerance) within the IEEE 802.3 specification and v10 XLS used for static port voltage calculations.

 

The last presentation given on this topic is available at:

http://grouper.ieee.org/groups/802/3/at/public/sep06/index.html