SMSC USB20H04 User Manual

 4-Port USB 2.0 Hub Controller 

 

Revision 1.63 (03-30-07) 

Page 6 

SMSC USB20H04 

 

 

 

The 4-Port Hub supports several OEM selectable features: 

ƒ 

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). 

ƒ 

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

ƒ 

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

ƒ 

Enable downstream facing port LED indicators. 

ƒ 

Select multiple or single transaction translator mode. 

ƒ  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). 

ƒ 

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

ƒ 

Enable downstream facing ports a port by port basis. 

ƒ 

Enable EOP generation of EOF1 when operating in full-speed mode, as described in Section 11.3.1 of 
the USB 2.0 Specification. 

ƒ 

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

ƒ 

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

ƒ 

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

ƒ 

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

ƒ 

Indicate the maximum current required for the hub controller. 

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.