ICS9248-192

ICS9248-192 Frequency Timing Generator for Transmeta Systems Recommended Application: Transmeta Output Features: 1CPU(2.5V or 3.3V selectable) up to 66.6MHz & overclocking of 66MHz. 6 PCI (3.3V) @ 33.3MHz (all are free running selectable). 1 REF (3.3V) at 14.318MHz. 1 48MHz (3.3V). 1 24_48MHz selectable output. Features: Supports Spread Spectrum modulation for CPU and PCI clocks, default -0.4 downspread. Efficient Power management scheme through stop clocks and power down modes. Uses external 14.318MHz crystal, no external load cap required for CL=18pF crystal. 28-pin TSSOP package, 4.40mm (173mil). Pin Configuration GNDREF 1 X1 2 X2 3 PD# 4 PCICLK0 5 PCICLK1 6 PCICLK2 7 GNDPCI 8 VDDPCI 9 PCICLK3 10 PCICLK4 11 PCICLK5 12 SDATA 13 SCLK 14 ICS9248-192 28 VDDREF 27 REF 26 CPU_STOP# 25 VDDLCPU 24 GNDLCPU 23 CPUCLK0 22 PCI_STOP# 21 GND_Core 20 VDD_Core 19 SEL66/60# 18 VDD48 17 GND48 16 48MHz/CPU3.3v_2.5V#sel 15 24-48MHz/Sel48_24# 28-Pin TSSOP Skew Characteristics: CPU – CPU <175ps PCI – PCI < 500ps CPU(early) – PCI = 1.5ns – 4ns. Block Diagram PLL2 X1 X2 SEL48_24# CPU3.3V_2.5V#sel SEL66/60# PD# PCI_STOP# CPU_STOP# SDATA SCLK 0540F—10/27/05 XTAL OSC PLL1 Spread Spectrum Control Logic Config. Reg. /2 CPU DIVDER Stop 48MHz 24_48MHz REF CPUCLK0 PCI DIVDER Stop PCICLK (5:0) 6 Power Groups VDD_Core, GND_Core = PLL core VDDREF, GNDREF = REF, X1, X2 VDDPCI, GNDPCI = PCICLK (5:0) VDD48, GND48 = 48MHz (1:0) ICS9248-192 Pin De...