ICS181-52
Low EMI Clock Generator
Description
Features
The ICS181-52 generates a low EMI output clock from
a clock or crystal input. The device uses ICS’
proprietary mix of analog and digital Phase Locked
Loop (PLL) technology to spread the frequency
spectrum of the output, thereby reducing the frequency
amplitude peaks by several dB.
• Pin and function compatible to Cypress W181-52
• Packaged in 8-pin SOIC
• Provides a spread spectrum output clock
• Accepts a clock input and provides same frequency
dithered output
• Input frequency of 28 to 48 MHz for Clock input
The ICS181-52 offers center spread selection of
+/-0.625% and +/-1.875%. Refer to the MK1714-01/02
for the widest selection of input frequencies and
multipliers.
• Peak reduction by 7dB - 14dB typical on 3rd - 19th
odd harmonics
• Spread percentage selection for +/-0.625% and
+/-1.875%
ICS offers a complete line of EMI reducing clock
generators. Consult us when you need to remove
crystals and oscillators from your board.
• Operating voltage of 3.3 V and 5 V
• Advanced, low-power CMOS process
Block Diagram
VDD
FS1
SSON#
PLL Clock
Synthesis
SS%
and Spread
Spectrum
Circuitry
CLK
X1/CLKIN
Clock Buffer/
Crystal
Oscillator
X2
GND
MDS 181-52 A
1
Revision 110404
Integrated Circuit Systemsl525 Race Street, San Jose, CA 95126 l tel (408) 297-1201 l www.icst.com
ICSI [ INTEGRATED CIRCUIT SOLUTION INC ]
