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RE: PSE vs. PD power dissipation again


I don't think any state machine(s) have been officially adopted yet.  I do
agree that Avaya has put forth the state diagrams for a proposed discovery
scheme, but I did not think that those had been voted by the 802.3af
committee into the status of PSE or PD requirements.  Therefore, I would
encourage that we keep an open mind as to what we should consider modifying,
and what benefits and liabilities accrue from such modifications prior to
the formal adoption of these technical suggestions.

I by no means seek to detract from the good work which Avaya has done.  I
merely seek to retain flexibility if and where it pays to do so.

Peter Schwartz
Applications Engineer
Micrel Semiconductor
Phone:	408.435.2460
FAX:	408.456.0490
peter.schwartz@xxxxxxxxxx <mailto:peter.schwartz@xxxxxxxxxx> 

Start-up voltage:  Yair allows the PD to drop the line voltage below the
start-up threshold of 30 volts.  All the state machines for the resistor
proposal have stated that the PD should only draw power if the voltage is
greater than start-up.  We can allow this, but it creates a special start-up