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| Datasheet |
| Table 4.1 | ||
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NAME | SYMBOL | TYPE | FUNCTION |
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USBDN[2:1] | These pins connect to the downstream USB peripheral | ||
Data | USBDP[2:1] |
| devices attached to the Hub’s ports. |
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USB Power | PRTPWR | O8 | Enables power to USB peripheral devices (downstream). |
Enable |
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| The active signal level of the PRTPWR pin is determined by |
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| the Power Polarity Strapping function of the PRTPWR_POL |
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| pin. |
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Port [2:1] Green | GR[2:1]/ | I/O8 | Green indicator LED for ports 2 and 1. Will be active low |
LED | NON_REM[1:0] |
| when LED support is enabled via EEPROM or SMBus. |
& |
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| If the hub is configured by the internal default configuration, |
Port Non- |
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| these pins will be sampled at the rising edge of RESET_N | |
Removable |
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| (see the applicable RESET_N timing table in Section 5.6.1) | |
strapping option. |
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| to determine if ports [2:1] contain permanently attached | |
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| will be determined as follows: |
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| NON_REM[1:0] = ‘00’, All ports are removable, |
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| GR2 is active high, |
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| GR1 is active high. |
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| NON_REM1:0] = ‘01’, Port 1 is |
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| GR2 is active high, |
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| GR1 is active low. |
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| NON_REM[1:0] = ‘10’, Ports 1 & 2 are |
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| GR2 is active low, |
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| GR1 is active high. |
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| NON_REM[1:0] = ‘11’, Ports 1 & 2 are |
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| GR2 is active low, |
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| GR1 is active low. |
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Port Power | PRTPWR_POL | I/O8 | Port Power Polarity strapping determination for the active |
Polarity strapping. |
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| signal polarity of the PRTPWR pin. |
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| While RESET_N is asserted, the logic state of this pin will |
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| (though the use of internal combinatorial logic) determine |
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| the active state of the PRTPWR pin in order to ensure that |
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| downstream port power is not inadvertently enabled to |
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| inactive ports during a hardware reset. |
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| On the rising edge of RESET_N (see the applicable |
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| RESET_N timing table in Section 5.6.1), the logic value will |
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| be latched internally, and will retain the active signal polarity |
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| for the PRTPWR pin. |
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| ‘1’ = PRTPWR pin has an active ‘high’ polarity |
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| ‘0’ = PRTPWR pin has an active ‘low’ polarity |
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Over Current | OCS_N | IPU | Input from external current monitor indicating an over- |
Sense |
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| current condition. {Note: Contains internal |
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| supply} |
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USB Transceiver | RBIAS | A 12.0kΩ (+/− 1%) resistor is attached from ground to this | |
Bias |
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| pin to set the transceiver’s internal bias settings. |
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Revision 2.3 | 12 | SMSC USB2502 |
| DATASHEET |
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