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| USB 2.0 |
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| Datasheet |
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| Table 3.1 USB2514 Pin Descriptions (continued) | ||
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| BUFFER |
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SYMBOL | 36 QFN | 48 QFN | TYPE | DESCRIPTION |
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SUSP_IND/ | 28 | 39 | I/O | Active/Suspend status LED or |
LOCAL_PWR/ |
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| Removable Strap Option |
NON_REM0 |
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| Suspend Indicator: Indicates USB state of the hub. |
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| ‘negated’ = Unconfigured, or configured and in USB |
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| Suspend |
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| ‘asserted’ = Hub is configured, and is active (i.e., not in |
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| suspend) |
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| Local Power: Detects availability of local |
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| source. |
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| Low = Self/local power source is NOT available (i.e., |
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| Hub gets all power from Upstream USB VBus). |
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| High = Self/local power source is available. |
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| NON_REM0 Strap Option: |
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| If this strap is enabled by package and configuration |
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| settings (see Table 3.2), this pin will be sampled (in |
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| conjunction with NON_REM1) at RESET_N negation to |
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| determine if ports [4:1] contain permanently attached |
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| LED will be determined as follows: |
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| NON_REM[1:0] = ‘00’, All ports are removable, and the |
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| LED is active high |
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| NON_REM[1:0] = ‘01’, Port 1 is nonremovable, and the |
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| LED is active low |
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| NON_REM[1:0] = ‘10’, Ports 1 & 2 are |
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| and the LED is active high |
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| NON_REM[1:0] = ‘11’, Ports 1, 2 & 3 are non- |
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| removable, and the LED is active low |
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TEST | 11 | 14 | IPD | TEST pin |
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| XNOR continuity tests all signal pins on the hub, please |
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| contact your SMSC representative for a detailed |
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| description of how this test mode is enabled and utilized. |
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SEL48 | n/a | 40 | I | Select 48 MHz clock input |
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| 48MHz external clock input select. When the hub is |
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| clocked from an external clock source, this pin selects |
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| either 24MHz or 48MHz mode. |
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| ‘0’ = 24MHz |
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| ‘1’ = 48MHz |
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REG_EN | n/a | 11 | IPU | Regulator Enable |
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| REG_EN: This pin is internally pulled up to enable the |
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| internal 1.8V regulators, and this pin should be treated |
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| as a |
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| In order to disable the regulators, this pin will need to be |
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| externally connected to ground. |
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| When the internal regulator is enabled, the 1.8V power |
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| pins must be left unconnected, except for the required |
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| bypass capacitors. |
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Revision 1.98 | 14 | SMSC USB2514 |
| DATASHEET |
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