AMD SC2200 User Manual
420
AMD Geode™ SC2200 Processor Data Book
Electrical Specifications
32580B
9.3.9
Universal Serial Bus (USB) Interface
Table 9-29. USB Timing Parameters
Symbol
Parameter
Min
Max
Unit
Figure
Comments
Full Speed Source (Note 1, Note 2)
t
USB_R1
DPOS_Port1,2,3, DNEG_Port1,2,3
Driver Rise Time
Driver Rise Time
4
20
ns
(Monotonic) from 10% to
90% of the D_Port lines
90% of the D_Port lines
t
USB_F1
DPOS_Port1,2,3, DNEG_Port1,2,3
Driver Fall Time
Driver Fall Time
4
20
ns
(Monotonic) from 90% to
10% of the D_Port lines
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%
± 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 for con-
secutive transition
secutive transition
–3.5
3.5
ns
Note 3, Note 4
t
USB_DJ12
Source differential driver jitter for paired
transitions
transitions
–4.0
4.0
ns
t
USB_SE1
Source EOP width
160
175
ns
t
USB_DE1
Differential to EOP transition skew
–2
5
ns
t
USB_RJ11
Receiver data jitter tolerance for con-
secutive transition
secutive transition
–18.5
18.5
ns
t
USB_RJ12
Receiver data jitter tolerance for paired
transitions
transitions
–9
9
ns
Full Speed Receiver EOP Width (Note 4)
t
USB_RE11
Must reject as EOP
40
ns
t
USB_RE12
Must accept as EOP
82
ns
Low Speed Source (Note 1)
t
USB_R2
DPOS_Port1,2,3, DNEG_Port1,2,3
Driver Rise Time
Driver Rise Time
75
300
(Note 6)
ns
(Monotonic) from 10% to
90% of the D_Port lines
90% of the D_Port lines
t
USB_F2
DPOS_Port1,2,3, DNEG_Port1,2,3
Driver Fall Time
Driver Fall Time
75
300
ns
(Monotonic) from 90% to
10% of the D_Port lines
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%
± 1.5%
t
PERIOD_L
Low-speed period
0.657
0.677
μs
at 1.5 Mbps
t
USB_DJD21
Source differential driver jitter for con-
secutive transactions
secutive transactions
–75
75
ns
Host (downstream),
Note 4
Note 4
t
USB_DJD22
Source differential driver jitter for paired
transactions
transactions
–45
45
ns
Host (downstream),
Note 4
Note 4
t
USB_DJU21
Source differential driver jitter for con-
secutive transaction
secutive transaction
–95
95
ns
Function (downstream),
Note 4
Note 4