USB2502 SMSC Corporation, USB2502 Datasheet - Page 13

• Manufacturer Part Number: USB2502
• Description: 2-Port USB 2.0 Hub Controller
• Manufacturer: SMSC Corporation

2-Port USB 2.0 Hub Controller
Datasheet
SMSC USB2502
Serial Clock/SMB
Serial Data/SMB
Crystal Output
Input/External
Config Select 0
RESET Input
Self-Power /
Programming
Clock Input
Clock Input
Configuration
Bus-Power
TEST Pin
Crystal
Enable
NAME
Detect
NAME
Select
Clock
Data
&
CFG_SEL1
SELF_PWR
SDA/SMBDATA
CLKIN_EN
SCL/SMBCLK/
RESET_N
SYMBOL
CFG_SEL0
CFG_SEL1
XTAL1/
CLKIN
XTAL2
0
0
1
1
TEST
SYMBOL
Table 4.1 2-Port Hub Pin Descriptions (continued)
Table 4.2 SMBus or EEPROM Interface Behavior
CFG_SEL0
0
1
0
1
IOSD12
IOSD12
Table 4.3 Miscellaneous Pins
OCLKx
SERIAL PORT INTERFACE
TYPE
ICLKx
TYPE
IPD
IS
I
I
I
DATASHEET
SMBus or EEPROM interface behavior.
Reserved
Configured as an SMBus slave for external download of user-
defined descriptors. SMBus slave address is 0101100
Internal Default Configuration via strapping options.
2-wire (I2C) EEPROMS are supported,
(Serial Data)/(SMB Data) signal.
(Serial Clock)/(SMB Clock) signal. This multifunction pin is
read on the rising edge of RESET_N (see the applicable
RESET_N timing table in
the hub configuration method as described in
This pin is read on the rising edge of RESET_N (see the
applicable RESET_N timing table in
determine the hub configuration method as described in
Table
13
24MHz crystal or external clock input.
This pin connects to either one terminal of the crystal or
to an external 24MHz clock when a crystal is not used.
24MHz Crystal
This is the other terminal of the crystal, or left
unconnected when an external clock source is used to
drive XTAL1/CLKIN. It must not be used to drive any
external circuitry other than the crystal circuit.
Clock In Enable:
Low = XTAL1 and XTAL2 pins configured for use with
external crystal
High = XTAL1 pin configured as CLKIN, and must be
driven by an external CMOS clock.
This active low signal is used by the system to reset the
chip. The minimum active low pulse is 1us.
Low = Self/local power source is NOT available (i.e., Hub
gets all power from Upstream USB VBus).
High = Self/local power source is available.
Used for testing the chip. User must treat as a no-
connect or connect to ground.
Detects availability of local self-power source.
4.2.
FUNCTION
FUNCTION
Section
5.6.1) and will determine
Section
Revision 2.1 (12-06-06)
5.6.1) and will
Table
4.2.