DATASHEET Advance Information TM Programmable System Clock Chip for ATI RS790 - K8 based 9LPRS471C Systems Key Specifications: Recommended Application: ATI RS790 systems using AMD K8 processors CPU outputs cycle-to-cycle jitter < 85ps SRC outputs cycle-to-cycle jitter < 125ps Output Features: ATIG outputs cycle-to-cycle jitter < 125ps 2 - Greyhound compatible K8 CPU pair +/- 300ppm frequency accuracy on CPU, SRC & ATIG clocks 6 - low-power differential SRC pairs 2 - low-power differential SouthBridge SRC pairs 4 - low-power differential ATIG pairs Features/Benefits: CPU, ATIG, SB SRC and SRC outputs are 1 - Selectable low-power differential 100MHz non- independently programmable for frequency spread SATA/ SRC output 1 - Selectable 100MHz low-power differential/ 66 MHz Spread Spectrum for EMI reduction single-ended HTT clock Outputs may be disabled via SMBus 2 - 48MHz USB clock External crystal load capacitors for maximum frequency accuracy 3 - 14.318MHz Reference clock Meets PCIEX Gen2 specifications Pin Configuration 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 1 48MHz 1 48 VDDCPU 2 48MHz 0 47 GNDCPU 3 GND48 46 CPUKG1T LPRS 4 SMBCLK 45 CPUKG1C LPRS 5 SMBDAT 44 VDDA 6 SRC5C LPRS 43 GNDA 7 SRC5T LPRS 42 GNDSATA 8 SRC4C LPRS 41 SRC6T/SATAT LPRS 9LPRS471C 9 SRC4T LPRS 40 SRC6C/SATAC LPRS GNDSRC 10 39 VDDSATA VDDSRC 11 38 ATIG0T LPRS SRC3C LPRS 12 37 ATIG0C LPRS SRC3T LPRS 13 36 ATIG1T LPRS SRC2C LPRS 14 35 ATIG1C LPRS SRC2T LPRS 15 34 VDDATIG VDDSRC 16 33 GNDATIG 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 64-Pin MLF * Internal Pull-Up Resistor ** Internal Pull-Down Resistor TM IDT Programmable System Clock Chip for ATI RS790 - K8 based Systems 139805/23/12 1 VDD48 GNDSRC SRC1C LPRS X2 SRC1T LPRS X1 SRC0C LPRS GNDREF SRC0T LPRS VDDREF SB SRC1C LPRS REF0/SEL HTT66 SB SRC1T LPRS REF1/SEL SATA GNDSB SRC REF2 VDDSB SRC VDDHTT SB SRC0C LPRS HTT0T LPRS/66M SB SRC0T LPRS HTT0C LPRS/66M GNDATIG GNDHTT ATIG3C LPRS RESTORE ATIG3T LPRS PD ATIG2C LPRS CPUKG0T LPRS ATIG2T LPRS CPUKG0C LPRS9LPRS471C Advance Information Frequency Timing Generator for Peripherals Pin Description PIN PIN NAME TYPE DESCRIPTION 1 48MHz 1 OUT 48MHz clock output. 2 48MHz 0 OUT 48MHz clock output. 3 GND48 GND Ground pin for the 48MHz outputs 4 SMBCLK IN Clock pin of SMBus circuitry, 5V tolerant. 5 SMBDAT I/O Data pin for SMBus circuitry, 5V tolerant. Complement clock of low power differential SouthBridge SRC clock pair. (no 50ohm shunt resistor to GND 6 SRC5C LPRS OUT and 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 7 SRC5T LPRS OUT series resistor needed Complement clock of low power differential SouthBridge SRC clock pair. (no 50ohm shunt resistor to GND 8 SRC4C LPRS OUT and 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 9 SRC4T LPRS OUT series resistor needed 10 GNDSRC GND Ground pin for the SRC outputs 11 VDDSRC PWR Supply for SRC core, 3.3V nominal Complement clock of low power differential SouthBridge SRC clock pair. (no 50ohm shunt resistor to GND 12 SRC3C LPRS OUT and 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 13 SRC3T LPRS OUT series resistor needed Complement clock of low power differential SouthBridge SRC clock pair. (no 50ohm shunt resistor to GND 14 SRC2C LPRS OUT and 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 15 SRC2T LPRS OUT series resistor needed 16 VDDSRC PWR Supply for SRC core, 3.3V nominal 17 GNDSRC GND Ground pin for the SRC outputs Complement clock of low power differential SouthBridge SRC clock pair. (no 50ohm shunt resistor to GND 18 SRC1C LPRS OUT and 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 19 SRC1T LPRS OUT series resistor needed Complement clock of low power differential SouthBridge SRC clock pair. (no 50ohm shunt resistor to GND 20 SRC0C LPRS OUT and 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 21 SRC0T LPRS OUT series resistor needed Complement clock of low power differential SouthBridge SRC clock pair. (no 50ohm shunt resistor to GND 22 SB SRC1C LPRS OUT and no 33 ohm series resistor needed True clock of low power differential SouthBridge SRC clock pair. (no 50ohm shunt resistor to GND and no 23 SB SRC1T LPRS OUT 33 ohm series resistor needed 24 GNDSB SRC GND Ground pin for the SB SRC outputs 25 VDDSB SRC PWR Supply for SRC core, 3.3V nominal Complement clock of low power differential SouthBridge SRC clock pair. (no 50ohm shunt resistor to GND 26 SB SRC0C LPRS OUT and no 33 ohm series resistor needed True clock of low power differential SouthBridge SRC clock pair. (no 50ohm shunt resistor to GND and no 27 SB SRC0T LPRS OUT 33 ohm series resistor needed 28 GNDATIG GND Ground pin for the ATIG outputs Complementary clock of low-power differential push-pull PCI-Express pair with integrated series resistor. 29 ATIG3C LPRS OUT (no 50ohm shunt resistor to GND and no 33 ohm series resistor needed) True clock of low-power differential push-pull PCI-Express pair with integrated series resistor. (no 50ohm 30 ATIG3T LPRS OUT shunt resistor to GND and no 33 ohm series resistor needed) Complementary clock of low-power differential push-pull PCI-Express pair with integrated series resistor. 31 ATIG2C LPRS OUT (no 50ohm shunt resistor to GND and no 33 ohm series resistor needed) True clock of low-power differential push-pull PCI-Express pair with integrated series resistor. (no 50ohm 32 ATIG2T LPRS OUT shunt resistor to GND and no 33 ohm series resistor needed) 33 GNDATIG GND Ground pin for the ATIG outputs 34 VDDATIG PWR Power supply for ATIG core, nominal 3.3V Complementary clock of low-power differential push-pull PCI-Express pair with integrated series resistor. 35 ATIG1C LPRS OUT (no 50ohm shunt resistor to GND and no 33 ohm series resistor needed) True clock of low-power differential push-pull PCI-Express pair with integrated series resistor. (no 50ohm 36 ATIG1T LPRS OUT shunt resistor to GND and no 33 ohm series resistor needed) TM IDT Programmable System Clock Chip for ATI RS790 - K8 based Systems 139805/23/12 2