Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

Re: [802.3_4PPOE] PD isolation requirements - Updated presentation for comments Comment r02-119, r02-70

Hi all,

probably the way to reach a possible definition for dual signature PDs that can tie positives is not to add an isolation requirement because it is not an isolated solution.
Furthermore the definition of dual signature PDs include an isolation requirement, then I suggest 2 action in order to obtain the target:
   - remove the additional requirement: Dual-signature PDs shall have less than or equal to 10 μA of current between any one conductor of Mode A and any one conductor of Mode B when VPD, as defined in 145.1.3, of either Mode is less than VOff_PD min, as defined in Table 145–9. See Table 79–f

2018-01-11 9:44 GMT+01:00 Andrea Agnes <andrea.agnes181@xxxxxxxxx>:

Hi Yair,


In my opinion there are 2 critical points in your proposal solution:


a)The voltage VPD is measured between any positive conductor of a pairset and any negative
conductor of the corresponding pairset, then it is not possible to measure current between negative pairs using VPD definition.


b)If PD dual signature ties positives together (problem #2, point d) and VPD is applied only to pairset mode A
at the negative pair of mode B the current is very higher than 30uA (for example if VPD is included in classification range).
Therefore your solution doesn’t include the possibility to join positive together in the dual signature PD.



Andrea AGNES | Tel: +39 0293517504

Analog & MEMS Group | Industrial & Power Conversion Division | IC Design Project Leader


STMicroelectronics srl

Via Tolomeo, 1 | 20010 Cornaredo (MI) | Italy


ST online: | Follow us on twitter: @st_world

2018-01-10 21:06 GMT+01:00 Yair Darshan <YDarshan@xxxxxxxxxxxxx>:

Hi all,

Please find updated presentation for comment r02-119 and r02-70.

Ill appreciate your inputs.



Darshan Yair

Chief R&D Engineer

Analog Mixed Signal Group

Microsemi Corporation


1 Hanagar St., P.O. Box 7220
Neve Ne'eman Industrial Zone
Hod Hasharon 45421, Israel
Tel:  +972-9-775-5100, EXT 210.

Cell: +972-54-4893019
Fax: +972-9-775-5111


E-mail: <mailto:ydarshan@xxxxxxxxxxxxx>.