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New Clock Generators Deliver Jitter Performance of 0.4 Picoseconds

03 November 2017

Mouser Electronics is now stocking the Si522xx PCIe clock generators from Silicon Labs. The new family of clock generators is compliant with all current versions of PCI Express® (PCIe®), including PCIe Gen 4 and Separate Reference Independent Spread (SRIS) standards. It delivers a jitter performance of 0.4 picoseconds RMS. The family’s wide-ranging applications include servers, storage, network interface cards, data centers, digital cameras and docking stations.

Si522xx PCIe clock generators. Source: Silicon LabsSi522xx PCIe clock generators. Source: Silicon Labs

The Silicon Labs Si522xx PCIe clock generators use low-power push-pull output technology to limit power consumption, reduce package size and eliminate the need for external terminating resistors in High-Speed Current Steering Logic (HCSL) outputs. The device’s internal power filtering reduces component count, which saves around 30 percent of board space.

The Si52212, Si52208 and Si52204 devices can source twelve, eight and four 100-megahertz PCIe differential clock outputs, respectively, plus one 25-megahertz LVCMOS reference clock output, while the Si52202 can source two 100-megahertz PCIe clock outputs only. All of the Si522xx devices have individual hardware control pins for enabling and disabling each output, spread spectrum enable/disable for EMI reduction and frequency selection for 133 or 200 megahertz differential output frequencies. These features can be controlled through I²C.

The Si522xx clock generators are supported by the Silicon Labs Si52204-EVB evaluation board. This board allows engineers to evaluate the four-output Si52204 clock generator. The board features I²C port access, plus jumpers and SMA connectors for easy static configuration of the control inputs and selector switches for selecting the voltage for both core and IO supplies.

To learn more about the clock generators, visit the Mouser site.

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