ICS650-01 Datasheet, PDF (1/4 Pages) Integrated Circuit Systems – System Peripheral Clock Source

Description
The ICS650-01 is a low cost, low jitter, high
performance clock synthesizer for system
peripheral applications. Using analog/digital
Phase-Locked Loop (PLL) techniques, the device
accepts a parallel resonant 14.31818 MHz crystal
input to produce up to eight output clocks. The
device provides clocks for PCI, SCSI, Fast
Ethernet, Ethernet, USB, and AC97. The user can
select one of three USB frequencies, and also one
of three AC97 audio frequencies. The OE pin puts
all outputs into a high impedance state for board
level testing. All frequencies are generated with less
than one ppm error, meeting the demands of SCSI
and Ethernet clocking.
The ICS650 can be mask customized to produce
any frequencies from 1 to 150 MHz.
ICS650-01
System Peripheral Clock Source
Features
• Packaged in 20 pin tiny SSOP (QSOP)
• Operating VDD of 3.3V or 5V
• Less than one ppm synthesis error in all clocks
• Inexpensive 14.31818 MHz crystal or clock input
• Provides Ethernet and Fast Ethernet clocks
• Provides SCSI clocks
• Provides PCI clocks
• Selectable AC97 audio clock
• Selectable USB clock
• OE pin tri-states the outputs for testing
• Selectable frequencies on three clocks
• Duty cycle of 40/60
• Advanced, low power CMOS process
Block Diagram
PSEL1:0
ASEL
USEL
14.31818 MHz
crystal _X1/ICLK
or clock
X2
2
Crystal
Oscillator
Clock
Synthesis
Circuitry
Output 4
Buffer
Output
Buffer
Output
Buffers
Output
Buffers
Output
Buffer
Processor Clocks
(Fast Ethernet,
SCSI, PCI )
Audio Clock
USB Clock
20 MHz
14.31818 MHz
Output Enable (all outputs)
MDS 650-01 C
1
Revision 092799
Printed 11/15/00
Integrated Circuit Systems • 525 Race Street • San Jose •CA•95126• [phone]tel • [phone]fax