IDT®

Programmable System Clock Chip for ATI RD790-K8TM Based Systems

1393—01/28/14

9LPRS477C

Programmable System Clock Chip for ATI RD790 - K8TM based Systems

3

VFQFPN Pin Description (Continued)

PIN #

PIN NAME

PIN TYPE

DESCRIPTION

33

GNDATIG

GND

Ground pin for the ATIG outputs

34

VDDATIG

PWR

Power supply for ATIG core, nominal 3.3V

35

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)

36

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)

37

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)

38

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)

39

VDDSATA

PWR

Power supply for SATA core logic, nominal 3.3V

40

SRC6C/SATAC_LPRS

OUT

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

33 ohm series resistor needed

41

SRC6T/SATAT_LPRS

OUT

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

series resistor needed

42

GNDSATA

GND

Ground pin for the SRC outputs

43

GNDA

GND

Ground for the Analog Core

44

VDDA

PWR

3.3V Power for the Analog Core

45

CPUKG1C_LPRS/SRC7C_LPRS

OUT

Complementary signal of low-power differential push-pull AMD K8 "Greyhound" clock with integrated series

resistor.(no 33 ohm series resistor needed) / Complement clock of low power differential SRC clock pair.

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

46

CPUKG1T_LPRS/SRC7T_LPRS

OUT

True signal of low-power differential push-pull AMD K8 "Greyhound" clock with integrated series resistor.

(no 33 ohm series resistor needed) / True clock of low power differential SRC clock pair. (no 50ohm shunt

resistor to GND and no 33 ohm series resistor needed

47

GNDCPU

GND

Ground pin for the CPU outputs

48

VDDCPU

PWR

Supply for CPU core, 3.3V nominal

49

CPUKG0C_LPRS

OUT

Complementary signal of low-power differential push-pull AMD K8 "Greyhound" clock with integrated series

resistor. (no 33 ohm series resistor needed)

50

CPUKG0T_LPRS

OUT

True signal of low-power differential push-pull AMD K8 "Greyhound" clock with integrated series resistor.(no

33 ohm series resistor needed)

51

PD#

IN

Enter /Exit Power Down.

0 = Power Down, 1 = normal operation.

52

RESTORE#

I/O

Open Drain I/O. As an input it restores the PLL's to power up default state. As an output, this signal is driven

low when the internal watchdog hardware timer expires. It is cleared when the internal watchdog hardware

timer is reset or disabled. The input is falling edge triggered.

0 = Restore Settings, 1 = normal operation.

53

GNDHTT

PWR

Ground pin for the HTT outputs

54

HTT0C_LPRS/66M

OUT

Complementary signal of low-power differential push-pull hypertransport clock with integrated series

resistor. (no 50ohm shunt resistor to GND and no 33 ohm series resistor needed) / 3.3V single ended

66MHz hyper transport clock

55

HTT0T_LPRS/66M

OUT

True signal of low-power differential push-pull hypertransport clock with integrated series resistor. (no

50ohm shunt resistor to GND and no 33 ohm series resistor needed) / 3.3V single ended 66MHz hyper

transport clock

56

VDDHTT

PWR

Supply for HTT clocks, nominal 3.3V.

57

REF2/SEL_OC_MODE**

I/O

14.318 MHz 3.3V reference clock./ SEl_OC_MODE: latched input to select pin functionality

1 = ATIG/SRC PCIE Gen1 Mode with higher overclocking ability

0 = ATIG/SRC PCIE Gen2 Mode with limited overclocking ability

58

REF1/SEL_SATA

I/O

14.318 MHz 3.3V reference clock./ 3.3V tolerant latched input to select function of SRC6/SATA output

0 = 100MHz differential spreading SRC clock, 1 = 100MHz non-spreading differential SATA clock

59

REF0/SEL_HTT66

I/O

14.318 MHz 3.3V reference clock./ 3.3V tolerant latched input to select Hyper Transport Clock Frequency.

0 = 100MHz differential HTT clock, 1 = 66MHz 3.3V single ended HTT clock

60

VDDREF

PWR

Ref, XTAL power supply, nominal 3.3V

61

GNDREF

GND

Ground pin for the REF outputs.

62

X1

IN

Crystal input, nominally 14.318MHz

63

X2

OUT

Crystal output, nominally 14.318MHz

64

VDD48

PWR

Power pin for the 48MHz outputs and core. 3.3V