[SI-LIST] Question about Broadcom's PHY differential pairs termination

Hi, experts,
     I'am designing with Broadcom PHY  BCM5461s, I have a question about
this phy's differential pairs termination.At Twisted pairs interface
side(interface between PHY and Transformer),ASIC's Datasheet and Application
note says "place differential pair termination resisters near PHY side as
close as possible"
      It seems clear that we put differential paris termination neart the
end of receiver(Rx direction), this method is also recommended by Dr. Howard
Johnson in his book"High-Speed Digital Design-a handbook of black magic "
pp-244,
     But why put termination also near driver side?(Tx direction) ,
     Could any one provide a deeper explanation? Thanks a lot!
     PS: A picture is inside  illustrating a reference termination.



-- Binary/unsupported file stripped by Ecartis --
-- Type: image/jpeg
-- File: termination.JPG


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