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CP3
BT26
30.13
USB PORT AC CHARACTERISTICS
30.14
MULTI-FUNCTION TIMER (MFT) TIMING
Figure 129.
Multi-Function Timer Input Timing
Table 90
USB Port Signals
Symbol
Description
Conditions
a
Min
Typ
Max
Units
T
R
Rise Time
C
L
= 50 pF
4
20
ns
T
F
Fall Time
C
L
= 50 pF
4
20
ns
T
RFM
Fall/Rise Time Matching (T
R
/T
F
)
C
L
= 50 pF
90
110
%
V
CRS
Output Signal Crossover Voltage
C
L
= 50 pF
1.3
2.0
V
Z
DRV
Driver Output Impedance
C
L
= 50 pF
28
43
ohms
a. Waveforms measured at 10% to 90%.
Table 91
Multi-Function Timer Input Signals
Symbol Figure
Description
Reference
Min (ns)
Max (ns)
t
TAH
129
TA High Time
Rising Edge (RE) on CLK
T
CLK
+ 5
t
TAL
129
TA Low Time
RE on CLK
T
CLK
+ 5
t
TBH
129
TB High Time
RE on CLK
T
CLK
+ 5
t
TBL
129
TB Low Time
RE on CLK
T
CLK
+ 5
t
TAL
/t
TBL
CLK
TA/TB
DS169
t
TAL
/t
TBH