Datasheet
The eye pattern in Figure 6.4 defines the transmit waveform requirements for a hub (measured at TP2 of Figure 6.3) or a device without a captive cable (measured at TP3 of Figure 6.3). The corresponding signal levels and timings are given in table below. Time is specified as a percentage of the unit interval (UI), which represents the nominal bit duration for a 480 Mbit/s transmission rate.
Level 1
400mV Differential
Point 3 | Point 4 |
Point 1 | Point 2 | 0 Volts |
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Level 2 |
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0% | Unit Interval | 100% | |||||
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Figure 6.4 Eye Pattern for Transmit Waveform and Eye Pattern Definition
| VOLTAGE LEVEL (D+, | TIME (% OF UNIT INTERVAL) |
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Level 1 | 525mV in UI following a transition, | N/A |
| 475mV in all others |
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Level 2 | N/A | |
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Point 1 | 0V | 7.5% UI |
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Point 2 | 0V | 92.5% UI |
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Point 3 | 300mV | 37.5% UI |
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Point 4 | 300mV | 62.5% UI |
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Point 5 | 37.5% UI | |
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Point 6 | 62.5% UI | |
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SMSC USB3280 | 19 | Revision 1.5 |
| DATASHEET |
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