DATASHEET
SERIAL PROGRAMMABLE QUAD PLL VERSACLOCK SYNTHESIZER
ICS308
Description
Features
The ICS308 is a versatile serially programmable, quad
PLL clock source. The ICS308 can generate any
frequency from 250 kHz to 200 MHz, and up to 6
different output frequencies simultaneously. The
outputs can be reprogrammed on the fly, and will lock to
a new frequency in 10 ms or less. Smooth transitions
(in which the clock duty cycle remains roughly 50%) are
guaranteed if the output divider is not changed.
ꢀ Packaged in 20-pin SSOP (QSOP) – Pb-free, RoHS
compliant
ꢀ Operating voltage of 3.3 V
ꢀ Highly accurate frequency generation
ꢀM/N Multiplier PLL: M = 1..2048, N = 1..1024
ꢀ Serially programmable: user determines the output
frequency via a 3-wire interface
The device includes a PDTS pin which tri-states the
output clocks and powers down the entire chip.
ꢀ Eliminates need for custom quartz oscillators
ꢀ Input crystal frequency of 5 - 27 MHz
ꢀOptional programmable on-chip crystal capacitors
ꢀ Output clock frequencies up to 200 MHz
ꢀ Reference clock output
The ICS308 default for non-programmed start-up are
buffered reference clock outputs on all clock output
pins.
ꢀ Power down tri-state mode
ꢀ Very low jitter
Block Diagram
3
VDD
CLK1
CLK2
PLL1
PLL2
PLL3
PLL4
STROBE
SCLK
CLK3
Divide
Logic
and
Output
Enable
Control
CLK4
DATA
CLK5
CLK6
CLK7
CLK8
CLK9
Crystal or
clock input
X1/ICLK
Crystal
Oscillator
X2
GND
2
External capacitors are
required with a crystal input.
PDTS
IDT™ / ICS™ SERIAL PROGRAMMABLE QUAD PLL VERSACLOCK SYNTHESIZER 1
ICS308
REV L 051310
IDT [ INTEGRATED DEVICE TECHNOLOGY ]
