USB 2.0
Datasheet
8.6.1.1RESET_N for Strapping Option Configuration
Hardware |
| Drive Strap | Attach |
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| Start | |
Read Strap | Outputs to | USB Reset |
| completion | |||
reset | USB | Idle | |||||
Options | inactive | recovery | request | ||||
asserted | Upstream |
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| levels |
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| response | |||
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RESET_N
t3
VSS |
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| t4 |
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Strap Pins |
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| Don’t Care | Valid | Don’t Care | Driven by Hub if strap is an output. |
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VSS |
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| Figure 8.3 Reset_N Timing for Default/Strap Option Mode |
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| Table 8.7 Reset_N Timing for Default/Strap Option Mode |
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NAME |
| DESCRIPTION | MIN | TYP | MAX | UNITS | |
t1 | RESET_N Asserted. |
| 1 |
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| μsec | |
t2 | Strap Setup Time |
| 16.7 |
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| nsec | |
t3 | Strap Hold Time. |
| 16.7 |
| 1400 | nsec | |
t4 | hub outputs driven to inactive logic states |
| 1.5 | 2 | μsec | ||
t5 | USB Attach (See Note). |
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| 100 | msec | |
t6 | Host acknowledges attach and signals USB | 100 |
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| msec | ||
| Reset. |
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t7 | USB Idle. |
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| undefined |
| msec |
t8 | Completion time for requests (with or without data |
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| 5 | msec | ||
| stage). |
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Notes:
When in
All power supplies must have reached the operating levels mandated in Chapter 9, DC Parameters, prior to (or coincident with) the assertion of RESET_N.
Revision 1.0 | 56 | SMSC USB251x |
DATASHEET