SMSC USB2503 Switch User Manual


 
Integrated USB 2.0 Compatible 3-Port Hub
Datasheet
Revision 2.3 (08-27-07) 16 SMSC USB2503/USB2503A
DATASHEET
This field is set by the OEM using either the SMBus or EEPROM interface options. When using the
internal default option, the NON_REM[1:0] pins will designate the appropriate ports as being non-
removable.
5.1.1.13 Self-Powered Port DISABLE
During Self-Powered operation, this selects the ports which will be permanently disabled, and are not
available to be enabled or enumerated by a Host Controller. The disabled ports must be contiguous,
and must be in decreasing order starting with port 3.
This field is set by the OEM using either the SMBus or EEPROM interface options. When using the
internal default option, the PRT_DIS0 pin will disable the appropriate ports.
5.1.1.14 Bus-Powered Port DISABLE
During Bus-Powered operation, this selects the ports which will be permanently disabled, and are not
available to be enabled or enumerated by a Host Controller. The disabled ports must be contiguous,
and must be in decreasing order starting with port 3.
This field is set by the OEM using either the SMBus or EEPROM interface options. When using the
internal default option, the PRT_DIS0 pin will disable the appropriate ports.
5.1.1.15 Dynamic Power
Controls the ability of the 3-Port Hub to automatically change from Self-Powered operation to Bus-
Powered operation if the local power source is removed or is unavailable (and from Bus-Powered to
Self-Powered if the local power source is restored). {Note: If the local power source is available, the
3-port Hub will always switch to Self-Powered operation.}
When Dynamic Power switching is enabled, the Hub detects the availability of a local power source
by monitoring the external SELF_PWR pin. If the Hub detects a change in power source availability,
the Hub immediately disconnects and removes power from all downstream devices and disconnects
the upstream port. The Hub will then re-attach to the upstream port as either a Bus-Powered Hub (if
local-power in unavailable) or a Self-Powered Hub (if local power is available).
This field is set by the OEM using either the SMBus or EEPROM interface options.
5.1.1.16 Over-Current Timer
The time delay (in 2ms increments) for an over-current condition to persist before it is reported to the
Host.
This field is set by the OEM using either the SMBus or EEPROM interface options.
5.1.1.17 Self-Powered Max Power
When in Self-Powered configuration, Sets value in 2mA increments.
This field is set by the OEM using either the SMBus or EEPROM interface options.
5.1.1.18 Bus-Powered Max Power
When in Bus-Powered configuration, Sets value in 2mA increments.
This field is set by the OEM using either the SMBus or EEPROM interface options.
5.1.1.19 Self-powered Hub Controller Current
When in Self-Powered configuration, Maximum current requirements of the Hub Controller in 2mA
increments.
This field is set by the OEM using either the SMBus or EEPROM interface options.