Table 4.5 buffer type descriptions, Datasheet – SMSC USB2503A User Manual
Page 13
Integrated USB 2.0 Compatible 3-Port Hub
Datasheet
SMSC USB2503/USB2503A
13
Revision 2.3 (08-27-07)
DATASHEET
VDD3P3
CORE
PLL
VDD33CR
+3.3V I/O and Core power.
VSS
VSS
Ground.
Table 4.5 Buffer Type Descriptions
BUFFER
DESCRIPTION
I
Input.
IPD
Input, with a weak Internal pull-down.
IPU
Input, with a weak Internal pull-up.
IS
Input with Schmitt trigger.
O12
Output 12mA.
I/O12
Input/Output, 12mA
IOSD12
Open drain….12mA sink with Schmitt trigger, and must meet I2C-Bus Specification Version 2.1
requirements.
ICLKx
XTAL Clock Input
OCLKx
XTAL Clock Output
I-R
*RBIAS.
IO-U
Defined in USB Specification.
Note: Meets USB 1.1 requirements when operating as a 1.1-compliant device and meets USB
2.0 requirements when operating as a 2.0-compliant device.
AIO
Analog Input/output. Per PHY test requirements.
Table 4.4 Power, Ground, and No Connect (continued)
NAME
SYMBOL
TYPE
FUNCTION