ICS345
Triple PLL Field Programmable SS VersaClock Synthesizer
Description
The ICS345 field programmable clock synthesizer
generates up to nine high-quality, high-frequency clock
outputs including multiple reference clocks from a
low-frequency crystal or clock input. It is designed to
replace crystals and crystal oscillators in most
electronic systems.
Using ICS’
software to configure PLLs
and outputs, the ICS345 contains a One-Time
Programmable (OTP) ROM to allow field
programmability. Programming features include eight
selectable configuration registers, up to two sets of four
low-skew outputs, and optional Spread Spectrum
outputs.
Using Phase-Locked Loop (PLL) techniques, the
device runs from a standard fundamental mode,
inexpensive crystal, or clock. It can replace multiple
crystals and oscillators, saving board space and cost.
The ICS345 is also available in factory programmed
custom versions for high-volume applications.
VersaClock
TM
Features
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Packaged as 20-pin SSOP (QSOP)
Spread spectrum capability
Eight addressable registers
Replaces multiple crystals and oscillators
Output frequencies up to 200 MHz at 3.3 V
Input crystal frequency of 5 to 27 MHz
Input clock frequency of 2 to 50 MHz
Up to nine reference outputs
Up to two sets of four low-skew outputs
Operating voltages of 3.3 V
Advanced, low-power CMOS process
For one output clock, use the ICS341. For two output
clocks, see the ICS342. For three output clocks, see
the ICS343. For more than three outputs, see the
ICS345 or ICS348.
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Available in Pb (lead) free packaging
Block Diagram
VDD
3
S 2:S 0
3
OTP
ROM
w ith
P LL
V alues
P LL1 with
S pread
S pectrum
D ivide
Logic
and
O utput
E nable
C ontrol
C LK 1
C LK 2
C LK 3
P LL2
C LK 4
C LK 5
C LK 6
C LK 7
C LK 8
C rystal or
clock input
X 1/IC LK
C rystal
O scillator
X2
P LL3
C LK 9
E xternal capacitors are
required w ith a crystal input.
GND
2
PD TS
MDS 345 E
Integrated Circuit Systems, Inc.
●
1
525 Race Street, San Jose, CA 95126
●
Revision 011205
tel (408) 297-1201
●
www.icst.com
IDT [ INTEGRATED DEVICE TECHNOLOGY ]
