Silicon Laboratories introduced the expansion of its Any-Rate Clock Generator family with the Si5355/56. The Si535x devices are made to order, 8-output CMOS clock generators capable of synthesizing four unique, non-integer related frequencies from 1-200 MHz. The Si535x clock generators provide guaranteed 0 ppm frequency synthesis error for any combination of frequencies, enabling the replacement of multiple clock ICs and crystal oscillators with a single device.

Through a flexible web configuration utility called ClockBuilder, factory-customized pin-controlled Si5355 devices are available in less than two weeks, enabling faster time to market while reducing the bill of materials in cost-sensitive networking, data communication, telecom access, computing and general purpose applications. The Si5355 leverages a single PLL architecture and Silicon Labs' MultiSynth fractional divider technology to provide greater frequency flexibility and lower jitter than 3 PLL or 4 PLL clock generators.

Since the Si5355 can synthesize all frequencies with 0 ppm error, it can replace multiple clock ICs and crystal oscillators with a single IC. The Si5355 has consistently low jitter (50 ps pk-pk period jitter) regardless of frequency configuration, providing significant margin to system-level jitter requirements. To further simplify design, the Si5355 can generate any combination of output frequencies from a standard, low cost 25 or 27 MHz crystal. If the device frequency plan changes, the same crystal can be reused, eliminating the higher cost associated with custom frequency crystals required by some traditional solutions.

Alternatively, the Si5355 supports a 5-200 MHz reference clock input, enabling the device to be used in synchronous applications. The Si535x family includes the Si5356, an I2C-programmable Any-Rate 1-200 MHz spread spectrum clock generator. Spread spectrum is available on any clock output with any frequency and any spread amount, providing a level of design flexibility not available from traditional solutions restricted to providing spread spectrum on only one or two frequencies. If system-level electro-magnetic interference (EMI) testing confirms that spread spectrum is required by an application, spread spectrum can simply be enabled by pin selection without the need for component or firmware changes, further simplifying qualification testing and shortening the overall development cycle.

Pricing and Availability

The Si5355/56 products are available in a space-saving 4x4 mm 24-QFN package with samples and production quantities available now. Pricing for the Si5355 is $3.00 in 10k quantities. The Si5356 is priced at $3.60 in 10k quantities. The ClockBuilder utility is available online. The Si5355-EVB and Si5356-EVB are available now and are each priced at $125 USD.