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CMOS Clock Generators Allow Frequency Selection From 1 To 200 MHz

Using a flexible web-based configuration utility, the Si5355/56 CMOS clock generators can be ordered for operation at any frequency from 1 to 200 MHz. These eight-output members of the Any-Rate clock generator family can synthesize four unique, non-interger-related frequencies. The devices promise to provide 0-ppm frequency-synthesis error for any combination of frequencies. In doing so, they enable the replacement of multiple clock ICs and crystal oscillators with a single device. To provide greater frequency flexibility and lower jitter than three- or four- phase-locked-loop (PLL) clock generators, the Si5355 leverages a single PLL architecture and the MultiSynth fractional divider technology.

The Si5355 provides 50-ps peak-to-peak period jitter regarding less of frequency configuration. It can generate any combination of output frequencies from a standard 25- or 27-MHz crystal. The Si535x family also includes the Si5356, an FC-programmable, 1-to-200-MHz spread-spectrum clock generator. Spread spectrum is available on any clock output with any frequency and spread amount. The Si5355/56 products come in a 4-x-4mm, 24-QFN package. P&A: $3.00 each for the Si5355 in lots of 10,000 and $3.60 for the Si5356 in similiar quantities. The ClockBuilder utility is available at

Silicon Laboratories, Inc., 400 West Cesar Chavez, Austin, TX 78701: (512) 416-8500 or (877) 444-3032, FAX: (512) 416-9669-, Internet:

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