ICS341
Field Programmable SS VersaClock Synthesizer
Description
The ICS341 is a low cost, single-output, field
programmable clock synthesizer. The ICS341 can
generate an output frequency from 250 kHz to 200
MHz and may employ Spread Spectrum techniques to
reduce system electro-magnetic interference (EMI).
Using ICS’ VersaClock™software to configure the PLL
and output, the ICS341 contains a One-Time
Programmable (OTP) ROM to allow field
programmability. Programming features include 4
selectable configuration registers.
The device employs Phase-Locked Loop (PLL)
techniques to run from a standard fundamental mode,
inexpensive crystal, or clock. It can replace multiple
crystals and oscillators, saving board space and cost.
The device also has a power-down feature that
tri-states the clock outputs and turns off the PLLs when
the PDTS pin is taken low.
The ICS341 is also available in factory programmed
custom versions for high-volume applications.
Features
• 8-pin SOIC package
• Highly accurate frequency generation
• M/N Multiplier PLL: M = 1...2048, N = 1...1024
• Output clock frequencies up to 200 MHz
• Four ROM locations for frequency and spread
selection
• Spread spectrum capability for lower system EMI
• Center or Down Spread up to 4% total
• Selectable 32 kHz or 120 kHz modulation
• Input crystal frequency from 5 to 27 MHz
• Input clock frequency from 2 to 50 MHz
• Operating voltage of 3.3 V
• Advanced, low-power CMOS process
• For two output clocks, use 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
Block Diagram
2
S1:0
Crystal or
clock input
X1/ICLK
X2
OTP ROM
with PLL
Divider
Values
Crystal
Oscillator
External capacitors are
required with a crystal input.
VDD
PLL Clock Synthesis,
Spred Spectrum and
CLK
Control Circuitry
GND
PDTS (output and PLL)
MDS 341 E
1
Revision 090704
Integrated Circuit Systems, Inc. ● 525 Race Street, San Jose, CA 95126 ● tel (408) 297-1201 ● www.icst.com