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34 page 
Integrated USB 2.0 Compatible 7-Port Hub Datasheet Revision 2.3 (08-27-07) 34 SMSC USB2507 DATASHEET 5.6.1.1 RESET_N for Strapping Option Configuration Figure 5.2 Reset_N Timing for Default/Strap Option Mode Notes: 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. All Power Supplies must have reached the operating levels mandated in Section Chapter 7, "DC Parameters", prior to (or coincident with) the assertion of RESET_N. Table 5.5 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 2.0 1.5 μsec t5 USB Attach (See Note). 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 |
