AT43301
15
Hub Differential Jitter:
T
HDJ1
= T
HDDX
(J) - T
HDDX
(K) or T
HDDX
(K) - T
HDDX
(J) Consecutive Transitions
T
HDJ2
= T
HDDX
(J) - T
HDDX
(J) or T
HDDX
(K) - T
HDDX
(K) Paired Transitions
Bit After Sop Width Distortion (Same as Data Jitter for Sop and Next J Transition):
T
SOP
= T
HDDX
(NEXTJ) - T
HDDX
(SOP)
Low-speed timings are determined in the same way for:
T
LHDD
, T
LDHJ1
, T
LDJH2
, T
LUHJ1
, T
LUJH2
, and T
LSOP
Figure 12. Hub EOP Delay and EOP Skew
EOP Delay:
T
EOPD
= T
EOP
- T
HDDX
EOP Skew:
T
HESK
= T
EOP +
-T
EOP-
Low-speed timings are determined in the same way for:
T
LEOPD
and T
LHESK
CROSSOVER
POINT
EXTENDED
DOWNSTREAM
PORT
A. DOWNSTREAM EOP DELAY WITH CABLE
50% POINT OF
INITIAL SWING
UPSTREAM
END OF
CABLE
UPSTREAM
PORT
V
SS
V
SS
V
SS
V
SS
B. DOWNSTREAM EOP DELAY WITHOUT CABLE
DOWNSTREAM
PORT
UPSTREAM
PORT OR END
OF CABLE
V
SS
V
SS
C. UPSTREAM EOP DELAY WITH OR WITHOUT CABLE
T
EOP-
T
EOP+
CROSSOVER
POINT
EXTENDED
DOWNSTREAM
PORT
T
EOP-
T
EOP+
CROSSOVER
POINT
EXTENDED
CROSSOVER
POINT
EXTENDED
T
EOP-
T
EOP+
CROSSOVER
POINT
EXTENDED
