MK1491-09 Datasheet, PDF (1/8 Pages) Integrated Circuit Systems – AMD Geode GX2 Clock Source

MK1491-09
AMD Geode™ GX2 Clock Source
Description
The MK1491-09 is a low-cost, low-jitter,
high-performance clock synthesizer for AMD’s
Geode-based computer and portable appliance
applications. Using patented analog Phased-Locked
Loop (PLL) techniques, the device accepts a 14.318
MHz crystal input to produce multiple output clocks. It
provides selectable PCI local bus clocks, 48 MHz
clocks for Super I/O and USB, as well as multiple
Reference outputs.
The device has multiple power-down modes to reduce
power consumption.
Block Diagram
VDD
6
GND
6
Features
• Packaged in 28-pin SSOP (209 mil body)
• Available in Pb (lead) free packaged
• Provides all critical timing for the AMD Geode
companion chip
• Four selectable PCI clocks
• Three LPC interface clocks
• One Fixed 66 MHz clock
• 2 Reference clocks
• 48 MHz USB and 48 MHz IO support
• Power down mode
• Low EMI Enable pin reduces EMI radiation on PCI
clocks, LCLKS, and 66 MHz clock
• Operating voltage of 3.3 V ±5%
Sel66/33#
PD#
Clocks
4 _{PCI (66/33 MHz)}
3
LCLK (33 MHz)
66 MHz
XI
14.31818 MHz
crystal
XO
Crystal
Oscillator
USB
Clock
48/TS#
48 MHz
REFCLK1
REFCLK0/Spread#
MDS 1491-09 G
1
Revision 080204
Integrated Circuit Systems, Inc. ● 525 Race Street, San Jose, CA 95126 ● tel [phone] ● www.icst.com