Reset_n for strapping option configuration, Datasheet – SMSC USB2524 User Manual
Page 48
USB MultiSwitch
TM
Hub
Datasheet
Revision 1.91 (08-22-07)
48
SMSC USB2524
DATASHEET
9.1.1.1
RESET_N for Strapping Option Configuration
Figure 9.1 Reset_N Timing for Default/Strap Option Mode
Note 9.1
When in Bus-Powered mode, the Hub and its associated circuitry must not consume more
than 100mA from the upstream USB power source during t1+t5.
Table 9.1 Reset_N Timing for Default/Strap Option Mode
NAME
DESCRIPTION
MIN
TYP
MAX
UNITS
t1
RESET_N Asserted.
1
μsec
t2
Strap Setup Time
16.7
nsec
t3
Strap Hold Time.
16.7
1400
nsec
t4
hub outputs driven to inactive logic states
1.5
2.0
μsec
t5
USB Attach (See
)
100
msec
t6
Host acknowledges attach and signals USB
Reset.
100
msec
t7
USB Idle.
undefined
msec
t8
Completion time for requests (with or without data
stage).
5
msec
t1
t4
t5
t6
t7
t8
Valid
Don’t Care
Don’t Care
Driven by Hub if strap is an output.
RESET_N
VSS
Strap Pins
VSS
Hardware
reset
asserted
Read Strap
Options
Drive Strap
Outputs to
inactive
levels
Attach
USB
Upstream
USB Reset
recovery
Idle
Start
completion
request
response
t2
t3