MK1493-01 Datasheet, PDF (1/13 Pages) Integrated Circuit Systems – PCI Clock Generator

MK1493-01
PCI Clock Generator
Description
The MK1493-01 is a general purpose clock generator
part that provides an integrated clocking solution for
PCI /networking applications. It provides 8 individually
programmable PCI clocks, 2 CPU clocks, additional
fixed PCI clocks and a 25 MHz reference clock for LAN
support. This part incorporates ICS’s newest clock
technology, offering more robust features and
functionality. Using a serially programmable SMBus
interface, the MK1493-01 can select the output clock
frequency, and enabling/disabling each individual
output clock.
Features
• 8 PCI clocks at 25, 33, 50, 66.66 MHz individually pin
selectableand serioal port slectable
• 2 CPU clocks at 100 MHz
• 2 PCI clocks at 66.66 MHz
• 1 PCI clock @ 50 MHz
• 25 MHz reference clock
• SMBus Programming
• Power-up default frequency can be selected through
FS inputs
• 25 MHz crystal or clock input required
• PCICLK cycle to cycle jitter <250ps
• CPUCLK cycle to cycle jitter <100ps
• Packaged in 48-pin (240mil) TSSOP Package
• Operating Voltage 3.3V + - 5%
Block Diagram
SCLK
SDATA
FS(0:7)_A ⁸
FS(0:7)_B ⁸
VDD
7
PLL
Divider
Buffer Circuits
SMBus Programmable
X1/CLK
25 MHz
X2
Clock Buffer/
Crystal
Ocsillator
7
GND
8
PCICLK(0:7)
Each PCI Output
Clock Individually
2
Programmable
CPUCLK(100MHz)
2
66M CLK
50M CLK
REFCLK
MDS 1493-01 B
1
Revision 021204
Integrated Circuit Systems, Inc. ● 525 Race Street, San Jose, CA 95126 ● tel [phone] ● www.icst.com