Frequency Timing Generator for Transmeta Systems - Integrated Circuit Systems
Description
Integrated Circuit Systems, Inc.
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.
Pin Configuration
GNDREF X1 X2 PD# PCICLK0 PCICLK1 PCICLK2 GNDPCI VDDPCI PCICLK3 PCICLK4 PCICLK5 SDATA SCLK
1 2 3 4 5 6 7 8 9 10 11 12 13 14
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).
Skew Characteristics: • CPU – CPU <175ps • PCI – PCI < 500ps • CPU(early) – PCI = 1.
5ns – 4ns.
28 27 26 25 24 23 22 21 20 19 18 17 16 15
VDDREF REF CPU_STOP# VDDLCPU GNDLCPU CPUCLK0 PCI_STOP# GND_Core VDD_Core SEL66/60# VDD48 GND48 48MHz/CPU3.
3v_2.
5V#sel 24-48MHz/Sel48_24#
28-Pin TSSOP
Block Diagram
PLL2 /2 X1 X2 XTAL OSC PLL1 Spread Spectrum 48MHz 24_48MHz
REF
CPU DIVDER
Stop
CPUCLK0
SEL48_24# CPU3.
3V_2.
5V#sel SEL66/60# PD# PCI_STOP# CPU_STOP# SDATA SCLK
Control Logic Config.
Reg.
PCI DIVDER
Stop
6
PCICLK (5:0)
Power Groups
VDD_Core, GND_Core = PLL core VDDREF, GNDREF = REF, X1, X2 VDDPCI, GNDPCI = PCICLK (5:0) VDD48, GND48 = 48MHz (1:0)
0540E—08/20/03
ICS9248-192
ICS9248-192
Pin Descriptions
Pin number 1 2 3 4 12, 11, 10, 7, 6, 5 8 9 15 13 14 16 48MHz 17 18 GND48 VDD48 Output Power Power Pin name GNDREF X1 X2 PD# PCICLK (5:0) GNDPCI VDDPCI Sel48_24# 24_48MHz SDATA SCLK CPU3.
3-2.
5# Type Power Input Output Input Output Power Power Input Output I/O IN Input Description Ground for 14.
318 MHz reference clock outputs 14.
318 MHz crystal input 14.
318 MHz crystal output Asynchronous active low input pin used to power down the device into a low power state.
The interna...
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