4-Port USB 2.0 Hub Controller

Datasheet

Revision 1.63 (03-30-07)

Page 6

SMSC USB20H04

DATASHEET

1.2

OEM Selectable Features

The 4-Port Hub supports several OEM selectable features:

Operation as a bus-powered, self-powered or dynamic-powered hub. (When configured for dynamic

operation, the controller automatically switches to bus-powered mode if a local power source is

unavailable).

Configure downstream facing port power switching on an individual or ganged basis.

Configure downstream facing port over-current sensing on an individual or ganged basis.

Enable downstream facing port LED indicators.

Select multiple or single transaction translator mode.

Select whether the hub is part of a compound device (when any downstream facing port is

permanently hardwired to a USB peripheral device, the hub is part of a compound device).

Select the presence of a permanently hardwired USB peripheral device on a port by port basis.

Enable downstream facing ports a port by port basis.

Enable EOP generation of EOF1 when operating in full-speed mode, as described in Section 11.3.1 of

the USB 2.0 Specification.

Enable USB On-The-Go Session Request Protocol (SRP) support.

Configure the delay time for filtering the over-current sense inputs.

Configure the delay time until port power is good after the SetPortPower command is received.

Indicate the maximum current that the 4-port hub consumes from an upstream port.

Indicate the maximum current required for the hub controller.

1.3

Pin Selectable Options to the Default Configuration

The USB20H04 includes a default configuration for those applications where an external EEPROM or

SMBus device is not available to provide the configuration. This configuration may be adequate in some

applications. A pin selectable feature supports configuration as either a bus-powered hub or a

self-powered hub determined by the logic level of the SELF_PWR pin following reset.