4-Port USB 2.0 Hub Controller

Datasheet

 

 

 

Table 4.3 - USB I/O Signals

 

 

 

 

NAME

BUFFER

ACTIVE

DESCRIPTION

TYPE

LEVEL

 

 

USBDP0

IO-U

N/A

Upstream USB Positive Data Pin.

USBDM0

IO-U

N/A

Upstream USB Negative Data Pin.

VBUSDET

IO8

N/A

Detects state of upstream VBUS power. When designing a detachable

 

 

 

hub, this pin must be connected to the VBUS power pin of the USB port

 

 

 

that is upstream of the hub.

 

 

 

For self-powered applications with a permanently attached upstream

 

 

 

host, this pin must be connected to either 3.3V or 5.0V (typically

 

 

 

VDD3.3).

 

 

 

The USB20H04 monitors VBUSDET to determine when to assert the

 

 

 

internal D+ pull-up resistor (signaling a connect event). When using the

 

 

 

SRP feature, it is necessary to add a 100k ohm resistor from this pin to

 

 

 

VSS in order to properly dissipate the upstream VBUS Pulse (pulsed with

 

 

 

an 8mA drive capability).

USBDP1

IO-U

N/A

USB Positive Data Pin to downstream port 1.

USBDM1

IO-U

N/A

USB Negative Data Pin to downstream port 1.

VBUS1_N

O8

Low

Enables power to downstream port 1.

OCS1_N

IPU

Low

Over-Current Sense input. Internal pull-up resistor to 3.3V.

GR1_N

OD8

Low

Enables green indicator to downstream port 1.

AM1_N

OD8

Low

Enables amber indicator to downstream port 1.

USBDP2

IO-U

N/A

USB Positive Data Pin to downstream port 2.

USBDM2

IO-U

N/A

USB Negative Data Pin to downstream port 2.

VBUS2_N

O8

Low

Enables power to downstream port 2.

OCS2_N

IPU

Low

Over-Current Sense input. Internal pull-up resistor to 3.3V.

GR2_N

OD8

Low

Enables green indicator to downstream port 2.

AM2_N

OD8

Low

Enables amber indicator to downstream port 2.

USBDP3

IO-U

N/A

USB Positive Data Pin to downstream port 3.

USBDM3

IO-U

N/A

USB Negative Data Pin to downstream port 3.

VBUS3_N

O8

Low

Enables power to downstream port 3.

OCS3_N

IPU

Low

Over-Current Sense input. Internal pull-up resistor to 3.3V.

GR3_N

OD8

Low

Enables green indicator to downstream port 3.

AM3_N

OD8

Low

Enables amber indicator to downstream port 3.

USBDP4

IO-U

N/A

USB Positive Data Pin to downstream port 4.

USBDM4

IO-U

N/A

USB Negative Data Pin to downstream port 4.

VBUS4_N

O8

Low

Enables power to downstream port 4.

OCS4_N

IPU

Low

Over-Current Sense input. Internal pull-up resistor to 3.3V.

GR4_N

OD8

Low

Enables green indicator to downstream port 4.

AM4_N

OD8

Low

Enables amber indicator to downstream port 4.

Revision 1.63 (03-30-07)

Page 10

SMSC USB20H04

DATASHEET