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G
Electrical Specifications
(Continued)
7.3.7
Universal Serial Bus (USB)
Table 7-23. USB Interface Signals
Symbol
Parameter
Min
Max
Unit
Figure
Comments
Full Speed Source
1
,
2
t
USB_R1
DPOS_Port1,2,3, DNEG_Port1,2,3
Driver Rise Time
4
20
ns
7-35
(Monotonic) from 10% to
90% of the D_Port lines
t
USB_F1
DPOS_Port1,2,3, DNEG_Port1,2,3
Driver Fall Time
4
20
ns
7-35
(Monotonic) from 90% to
10% of the D_Port lines
t
USB_FRFM
Rise/Fall time matching
90
110
%
t
USB_FSDR
Full-speed data rate
11.97
12.03
Mbps
Average bit rate 12 Mbps
±
0.25%
t
USB_FSF
Full-speed frame interval
0.9995
1.0005
ms
1.0 ms
±
0.05%
t
period_F
Full-speed period between data bits
83.1
83.5
ns
Average bit rate 12 Mbps
t
USB DOR
Driver-output resistance
28
43
W
Steady-state drive
t
USB_DJ11
Source differential driver jitter
3, 4
for
consecutive transition
–3.5
3.5
ns
7-36
t
USB_DJ12
Source differential driver jitter
3, 4
for
paired transitions
–4.0
4.0
ns
7-36
t
USB_SE1
Source EOP width
4, 5
160
175
ns
7-36
t
USB_DE1
Differential to EOP transition skew
4, 5
–2
5
ns
7-37
t
USB_RJ11
Receiver data jitter tolerance
4
for
consecutive transition
–18.5
18.5
ns
7-38
t
USB_RJ12
Receiver data jitter tolerance
4
for
paired transitions
–9
9
ns
7-38
Full Speed Receiver EOP Width
4
t
USB_RE11
Must reject as EOP
5
40
ns
7-37
t
USB_RE12
Must accept as EOP
5
82
ns
7-37
Low Speed Source
1, 6
t
USB_R2
DPOS_Port1,2,3, DNEG_Port1,2,3
Driver Rise Time
75
300
6
ns
7-35
(Monotonic) from 10% to
90% of the D_Port lines
t
USB_F2
DPOS_Port1,2,3, DNEG_Port1,2,3
Driver Fall Time
75
300
6
ns
7-35
(Monotonic) from 90% to
10% of the D_Port lines
t
USB_LRFM
Low-speed Rise/Fall time matching
80
120
%
t
USB_LSDR
Low-speed data rate
1.4775
1.5225
Mbps
Average bit rate 1.5 Mbps
±
1.5%
t
PERIOD_L
Low-speed period
0.657
0.677
μ
s
at 1.5 Mbps
t
USB_DJD21
Source differential driver jitter
4
for
consecutive transactions
–75
75
ns
Host (downstream)
t
USB_DJD22
Source differential driver jitter
4
for
paired transactions
–45
45
ns
7-36
Host (downstream)
t
USB_DJU21
Source differential driver jitter
4
for
consecutive transaction
–95
95
ns
7-36
Function (downstream)