PRELIMINARY INFORMATION
ICS290
Triple PLL Field Prog. Spread Spectrum Clock Synthesizer
Description
Features
• Packaged as 20-pin TSSOP
The ICS290 field programmable spread spectrum
clock synthesizer generates up to eight high-quality,
high-frequency clock outputs including multiple
reference clocks from a low-frequency crystal input. It
is designed to replace crystals, crystal oscillators and
stand alone spread spectrum devices in most
electronic systems.
• Eight addressable registers
• Replaces multiple crystals and oscillators
• Output frequencies up to 200 MHz at 3.3 V
• Configurable Spread Spectrum Modulation
• Input crystal frequency of 5 to 27 MHz
• Clock input frequency of 3 to 166 MHz
• Up to eight reference outputs
TM
Using ICS’ VersaClock software to configure PLLs
and outputs, the ICS290 contains a One-Time
Programmable (OTP) ROM for field programmability.
Programming features include input/output
frequencies, spread spectrum amount, eight selectable
configuration registers and up to two sets of four
low-skew outputs.
• Up to two sets of four low-skew outputs
• Operating voltages of 3.3 V
• Controllable output drive levels
• Advanced, low-power CMOS process
• Available in Pb (lead) free packaging
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 ICS290 is also available in factory programmed
custom versions for high-volume applications.
Block Diagram
3
VDD
PLL1 with
Spread
Spectrum
CLK1
CLK2
CLK3
CLK4
CLK5
CLK6
CLK7
CLK8
3
S2:S0
OTP
ROM
with PLL
Values
Divide
Logic
and
Output
Enable
Control
PLL2
PLL3
X1/ICLK
Crystal
Oscillator
Crystal or
Clock Input
X2
GND
3
External capacitors
are required with a crystal input.
PDTS
MDS 290 C
1
Revision 062305
Integrated Circuit Systems, Inc. ● 525 Race Street, San Jose, CA 95126 ● tel (408) 297-1201 ● www.icst.com