4th Generation USB 2.0 Flash Media Controller with Integrated Card Power FETs & HS Hub

Datasheet

Chapter 6 Pin Descriptions

This section provides a detailed description of each signal. The signals are arranged in functional groups according to their associated interface.

The “n” or “_N” symbol in the signal name indicates that the active, or asserted state occurs when the signal is at a low voltage level. When “n” is not present before the signal name (or “_N” after the signal name), the signal is asserted when at the high voltage level.

The terms assertion and negation are used exclusively. This is done to avoid confusion when working with a mixture of “active low” and “active high” signal. The term assert, or assertion indicates that a signal is active, independent of whether that level is represented by a high or low voltage. The term negate, or negation indicates that a signal is inactive.

6.1PIN Descriptions

 

 

 

BUFFER

 

NAME

SYMBOL

 

TYPE

DESCRIPTION

 

 

 

 

 

 

 

UPSTREAM USB INTERFACE

 

 

 

 

 

USB Bus Data

USBUP_DM

 

IO-U

These pins connect to the Upstream USB bus data

 

USBUP_DP

 

 

signals.

 

 

 

 

 

Detect Upstream

VBUS_DET

 

I/O12

Detects state of Upstream VBUS power. The SMSC

VBUS Power

 

 

 

Hub monitors VBUS_DET to determine when to assert

 

 

 

 

the internal D+ pull-up resistor (signalling a connect

 

 

 

 

event).

 

 

 

 

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 host, this pin must be pulled-up to either 3.3V

 

 

 

 

or 5.0V (typically VDD33).

 

 

 

 

 

 

 

 

3-PORT USB INTERFACE

 

 

 

 

 

USB Bus Data

USBDN_DM

 

IO-U

These pins connect to the Downstream USB bus data

 

[4:2]

 

 

signals.

 

USBDN_DP

 

 

 

 

[4:2]

 

 

 

 

 

 

 

 

USB Power Enable

PRTPWR[4:2]

 

I/O12

Enables power to USB peripheral devices

 

 

 

 

(downstream).

 

 

 

 

The active signal level of the PRTPWR[4:2] pins is

 

 

 

 

determined by the Power Polarity Strapping function of

 

 

 

 

the PRTPWR_POL pin.

 

 

 

 

 

Port Power Polarity

PRTPWR_POL

 

I/O12

Port Power Polarity strapping determination for the

Strapping

 

 

 

active signal polarity of the PRTPWR[4:2] pins.

 

 

 

 

While RESET_N is asserted, the logic state of this pin

 

 

 

 

will (though the use of internal combinatorial logic)

 

 

 

 

determine the active state of the PRTPWR[4:2] pins in

 

 

 

 

order to ensure that downstream port power is not

 

 

 

 

inadvertently enabled to inactive ports during a

 

 

 

 

hardware reset.

 

 

 

 

‘1’ = PRTPWR[4:2] pins have an active ‘high’ polarity

 

 

 

 

‘0’ = PRTPWR[4:2] pins have an active ‘low’ polarity

 

 

 

 

 

Revision 1.6 (06-20-08)

14

SMSC USB2601/USB2602

 

DATASHEET