USB MultiSwitchTM Hub
Datasheet
Table 4.2 SMBus or EEPROM Interface Behavior (continued)
NAME |
| NAME |
| NAME |
| FUNCTION |
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1 | 0 | 0 | Internal Default Configuration | |||
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| PRT_ASSIGN[3:0] = Peripheral Mode (Edge Triggered) | |
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| LED Mode = Host Ownership Mode | |
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| Strap | |
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| options on pins LED_A[4:1]_N are enabled. | |
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| Supports unassigned Ports | |
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1 | 0 | 1 | Internal Default Configuration | |||
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| PRT_ASSIGN[3:0] = Peripheral Mode (Edge Triggered) | |
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| LED Mode = Host Ownership & Port Speed Mode | |
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| Strap options on pins LED_A[4:1]_N are disabled | |
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| Supports unassigned Ports. | |
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1 | 1 | 0 | Reserved | |||
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1 | 1 | 1 | Reserved | |||
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| Table 4.3 Miscellaneous Pins | ||
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NAME |
| SYMBOL |
| TYPE |
| FUNCTION |
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Crystal |
| XTAL1/ |
| ICLKx |
| 24MHz crystal or external clock input. |
Input/External |
| CLKIN |
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| This pin connects to either one terminal of the crystal or |
Clock Input |
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| to an external 24MHz clock when a crystal is not used. |
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| Note: See Table 11.1 for the required logic voltage |
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| levels of this pad if it will be driven by an |
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| external clock source. |
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Crystal Output |
| XTAL2 |
| OCLKx |
| 24MHz Crystal |
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| This is the other terminal of the crystal, or left |
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| unconnected when an external clock source is used to |
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| drive XTAL1/CLKIN. It must not be used to drive any |
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| external circuitry other than the crystal circuit. |
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RESET Input |
| RESET_N |
| IS |
| This active low signal is used by the system to reset the |
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| chip. The minimum active low pulse is 1us. |
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| SELF_PWR |
| I |
| Detects availability of local | |
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| Low = Self/local power source is NOT available (i.e., Hub | |
Detect |
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| gets all power from Upstream USB VBus). |
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| High = Self/local power source is available. |
TEST Pin |
| TEST |
| IPD |
| Used for testing the chip. User must treat as a no- |
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| connect or connect to ground. |
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| Table 4.4 Power, Ground, and No Connect | |||
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NAME |
| SYMBOL |
| TYPE |
| FUNCTION |
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VDD Core |
| VDDCR18 |
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| +1.8V core power. |
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| Pins 16 and 50 must have a 4.7μF (or greater) ±20% |
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| (ESR <0.1Ω) capacitor to VSS |
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VDDIO 3.3V |
| VDD33 |
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| +3.3V Power Supply for the Digital I/O. |
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SMSC USB2524 | 15 | Revision 1.91 |
| DATASHEET |
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