SMSC USB2640i - Manual (Page 23)

Ultra Fast USB 2.0 Multi-Format Flash Media Controller/USB Hub Combo
SMSC USB2640/USB2641 23 Revision 2.0 (10-03-08)
DATASHEET
6.2 Buffer Type Descriptions
Table 6.2 USB2640/USB2641 Buffer Type Descriptions
BUFFER DESCRIPTION
I Input.
IPU Input, weak internal pull-up.
IS Input with Schmitt trigger.
I/O12 Input/output buffer with 12 mA sink and 12 mA source.
I/O200 Input/output buffer 12 mA with FET disabled, 100/200 mA source only when the FET
is enabled.
I/O12PD Input/output buffer with 12 mA sink and 12 mA source, with an internal weak pull-down
resistor.
I/O12PU Open drain, 12 mA sink with pull-up. Input with Schmitt trigger.
I/OD12PU Input/open drain output buffer with a 12 mA sink.
O12 Output buffer with a 12 mA sink and a 12 mA source.
O12PD Output buffer with 12 mA sink and 12 mA source, with a pull-down resistor.
O12PU Output buffer with 12 mA sink and 12 mA source, with a pull-up resistor.
ICLKx XTAL clock input.
OCLKx XTAL clock output.
I/O-U Analog input/output defined in USB specification.
I-R RBIAS.