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Philips Semiconductors
ISP1521
Hi-Speed USB hub controller
Product data Rev. 03 — 24 November 2004 41 of 53
9397 750 13702
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
T
PERIOD
is the bit duration corresponding with the USB data rate.
Full-speed timing symbols have a subscript prefix ‘F’, low-speed timing a prefix ‘L’.
Fig 11. Source differential data-to-EOP transition skew and EOP width.
mgr776
T
PERIOD
differential
data lines
crossover point
differential data to
SE0/EOP skew
N × T
PERIOD
+ t
DEOP
source EOP width: t
EOPT
receiver EOP width: t
EOPR
crossover point
extended
+3.3 V
0 V
T
PERIOD
is the bit duration corresponding with the USB data rate.
t
JR
is the jitter reference point.
Fig 12. Receiver differential data jitter.
mgr871
T
PERIOD
t
JR
differential
data lines
+3.3 V
0 V
t
JR1
t
JR2
consecutive
transitions
N × T
PERIOD
+ t
JR1
paired
transitions
N × T
PERIOD
+ t
JR2
Fig 13. Receiver SE0 width tolerance.
mgr872
differential
data lines
+3.3 V
0 V
t
FST
V
IH(min)