2

Integrated

Circuit

Systems, Inc.

ICS9EPRS488

Datasheet

1616—08/20/09

Pin Description

PIN #

PIN NAME

PIN TYPE

DESCRIPTION

1

SMBCLK

IN

Clock pin of SMBus circuitry, 5V tolerant.

2

SMBDAT

I/O

Data pin for SMBus circuitry, 5V tolerant.

3

VDD

PWR

Power supply for SRC7/27MHz

4

SRC7C_LPRS/27MHz_NS

OUT

True clock of low power differential SRC clock pair. (no 50ohm shunt resistor to GND and no 33 ohm

series resistor needed)/27MHz 3.3V Single-ended non-spread output for discrete graphics

5

SRC7T_LPRS/27MHz_SS

OUT

Complement clock of low power differential SRC clock pair. (no 50ohm shunt resistor to GND and no 33

ohm series resistor needed)/27MHz 3.3V Single-ended spreading output for discrete graphics

6

GND

GND

Ground pin for SRC7/27MHz

7

SRC5C_LPRS

OUT

Complement clock of low power differential SRC clock pair. (no 50ohm shunt resistor to GND and no 33

ohm series resistor needed)

8

SRC5T_LPRS

OUT

True clock of low power differential SRC clock pair. (no 50ohm shunt resistor to GND and no 33 ohm

series resistor needed)

9

SRC4C_LPRS

OUT

Complement clock of low power differential SRC clock pair. (no 50ohm shunt resistor to GND and no 33

ohm series resistor needed)

10

SRC4T_LPRS

OUT

True clock of low power differential SRC clock pair. (no 50ohm shunt resistor to GND and no 33 ohm

series resistor needed)

11

GNDSRC

GND

Ground pin for the SRC outputs

12

VDDSRC_IO

PWR

Power supply for differential SRC outputs, nominal 1.05V to 3.3V

13

SRC3C_LPRS

OUT

Complement clock of low power differential SRC clock pair. (no 50ohm shunt resistor to GND and no 33

ohm series resistor needed)

14

SRC3T_LPRS

OUT

True clock of low power differential SRC clock pair. (no 50ohm shunt resistor to GND and no 33 ohm

series resistor needed)

15

SRC2C_LPRS

OUT

Complement clock of low power differential SRC clock pair. (no 50ohm shunt resistor to GND and no 33

ohm series resistor needed)

16

SRC2T_LPRS

OUT

True clock of low power differential SRC clock pair. (no 50ohm shunt resistor to GND and no 33 ohm

series resistor needed)

17

VDDSRC

PWR

Supply for SRC core, 3.3V nominal

18

VDDSRC_IO

PWR

Power supply for differential SRC outputs, nominal 1.05V to 3.3V

19

GNDSRC

GND

Ground pin for the SRC outputs

20

SRC1C_LPRS

OUT

Complement clock of low power differential SRC clock pair. (no 50ohm shunt resistor to GND and no 33

ohm series resistor needed)

21

SRC1T_LPRS

OUT

True clock of low power differential SRC clock pair. (no 50ohm shunt resistor to GND and no 33 ohm

series resistor needed)

22

SRC0C_LPRS

OUT

Complement clock of low power differential SRC clock pair. (no 50ohm shunt resistor to GND and no 33

ohm series resistor needed)

23

SRC0T_LPRS

OUT

True clock of low power differential SRC clock pair. (no 50ohm shunt resistor to GND and no 33 ohm

series resistor needed)

24

**CLKREQ0#

IN

Clock Request pin for SRC0 outputs. If output is selected for control, then that output is controlled as

follows:

0 = enabled, 1 = Low-Low

25

ATIG2C_LPRS

OUT

Complementary clock of low-power differential push-pull PCI-Express pair with integrated series

resistor. (no 50ohm shunt resistor to GND and no 33 ohm series resistor needed)

26

ATIG2T_LPRS

OUT

True clock of low-power differential push-pull PCI-Express pair with integrated series resistor. (no

50ohm shunt resistor to GND and no 33 ohm series resistor needed)

27

GNDATIG

GND

Ground pin for the ATIG outputs

28

VDDATIG_IO

PWR

Power supply for differential ATIG outputs, nominal 1.05V to 3.3V

29

VDDATIG

PWR

Power supply for ATIG core, nominal 3.3V

30

ATIG1C_LPRS

OUT

Complementary clock of low-power differential push-pull PCI-Express pair with integrated series

resistor. (no 50ohm shunt resistor to GND and no 33 ohm series resistor needed)

31

ATIG1T_LPRS

OUT

True clock of low-power differential push-pull PCI-Express pair with integrated series resistor. (no

50ohm shunt resistor to GND and no 33 ohm series resistor needed)

32

ATIG0C_LPRS

OUT

Complementary clock of low-power differential push-pull PCI-Express pair with integrated series

resistor. (no 50ohm shunt resistor to GND and no 33 ohm series resistor needed)

33

ATIG0T_LPRS

OUT

True clock of low-power differential push-pull PCI-Express pair with integrated series resistor. (no

50ohm shunt resistor to GND and no 33 ohm series resistor needed)

34

SB_SRC1C_LPRS

OUT

Complement clock of low power differential Chipset-to-Chipset SRC clock pair. (no 50ohm shunt resistor

to GND and no 33 ohm series resistor needed

35

SB_SRC1T_LPRS

OUT

True clock of low power differential Chipset-to-Chipset SRC clock pair. (no 50ohm shunt resistor to GND

and no 33 ohm series resistor needed

36

GNDSB_SRC

GND

Ground pin for the SB_SRC outputs