Integrated USB 2.0 Compatible 4-Port Hub

Datasheet

Table 4.1 4-Port Hub Pin Descriptions (continued)

NAME

SYMBOL

TYPE

FUNCTION

 

 

 

 

 

 

4-PORT USB 2.0 HUB INTERFACE

 

 

 

 

High-Speed USB

USBDN[4:1]

IO-U

These pins connect to the downstream USB peripheral

Data

USBDP[4:1]

 

devices attached to the Hub’s ports.

 

 

 

 

USB Power

PRTPWR[4:1]

O12

Enables power to USB peripheral devices (downstream).

Enable

 

 

The active signal level of the PRTPWR[4:1] pins is

 

 

 

 

 

 

determined by the Power Polarity Strapping function of the

 

 

 

PRTPWR_POL pin.

 

 

 

 

Port 4:3 Green

GR[4:3]/

I/O12

Green indicator LED for ports 4 and 3. Will be active low

LED

PRT_DIS[1:0]

 

when LED support is enabled via EEPROM or SMBus.

&

 

 

If the hub is configured by the internal default configuration,

Port Disable

 

 

 

 

these pins will be sampled at RESET_N negation to

strapping option.

 

 

 

 

determine if ports [4:2] will be permanently disabled. Also,

 

 

 

 

 

 

the active state of the LED’s will be determined as follows:

 

 

 

PRT_DIS[1:0] = ‘00’, All ports are enabled,

 

 

 

GR4 is active high,

 

 

 

GR3 is active high.

 

 

 

PRT_DIS[1:0] = ‘01’, Port 4 is disabled,

 

 

 

GR4 is active high,

 

 

 

GR3 is active low.

 

 

 

PRT_DIS[1:0] = ‘10’, Ports 4 & 3 are disabled,

 

 

 

GR4 is active low,

 

 

 

GR3 is active high.

 

 

 

PRT_DIS[1:0] = ‘11’, Ports 4, 3 & 2 are disabled,

 

 

 

GR4 is active low,

 

 

 

GR3 is active low.

 

 

 

 

Port [2:1] Green

GR[2:1]/

I/O12

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.

&

 

 

If the hub is configured by the internal default configuration,

Port Non-

 

 

 

 

these pins will be sampled at RESET_N negation to

Removable

 

 

 

 

determine if ports [3:1] contain permanently attached (non-

strapping option.

 

 

 

 

removable) devices. Also, the active state of the LED’s will

 

 

 

be determined as follows:

 

 

 

NON_REM[1:0] = ‘00’, All ports are removable,

 

 

 

GR2 is active high,

 

 

 

GR1 is active high.

 

 

 

NON_REM[1:0] = ‘01’, Port 1 is non-removable,

 

 

 

GR2 is active high,

 

 

 

GR1 is active low.

 

 

 

NON_REM[1:0] = ‘10’, Ports 1 & 2 are non-removable,

 

 

 

GR2 is active low,

 

 

 

GR1 is active high.

 

 

 

NON_REM[1:0] = ‘11’, Ports 1, 2, & 3 are non-removable,

 

 

 

GR2 is active low,

 

 

 

GR1 is active low.

 

 

 

 

SMSC USB2504/USB2504A

11

Revision 2.3 (08-27-07)

 

DATASHEET