DATASHEET
TRIPLE PLL FIELD PROGRAMMABLE SS VERSACLOCK SYNTHESIZER
ICS345
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 IDT’s VersaClock
TM
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.
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.
Available in Pb (lead) free packaging
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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
IDT™ / ICS™
TRIPLE PLL FIELD PROGRAMMABLE SS VERSACLOCK SYNTHESIZER 1
ICS345
REV K 110207
IDT [ INTEGRATED DEVICE TECHNOLOGY ]
