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[802.3_100GNGOPTX] Fwd: [802.3_100GNGOPTX] Sinusoidal Jitter Generation mask?



Somehow the first message did not go through!

Begin forwarded message:

Date: November 8, 2012 12:38:16 PM PST
To: Vinu Arumugham <vinu@xxxxxxxxx>
Subject: Re: [802.3_100GNGOPTX] Sinusoidal Jitter Generation mask?

Vinu

These standards also define as part of the transmitter testing at least in Ethernet a Golden CDR with
loop bandwidth of 1/2500 of Baudrate.  The CDR help integrate TX SJ contribution then you make lump
sum measurement of the jitter on your favorite instrument.  If you have excess SJ the transmit test with
Golden PLL give you credit by tracking the allowed portion and any excess will be part of the measurement,
so there is no reason beside de-bugging the transmitter to directly measure the TX SJ.

Thanks,
Ali


On Nov 8, 2012, at 8:29 AM, Vinu Arumugham wrote:

All,

A basic spec. question ...
Most serial link electrical specifications have a Sinusoidal Jitter (SJ) tolerance mask for the RX.
But I have never seen a Sinusoidal Jitter Generation mask for the TX. Why?
The interconnect cannot be the source of all that SJ...

Thanks,
Vinu