The role of a jitter cleaner

Some of you may not have used a jitter cleaner before, so here's a brief explanation of its function.

A jitter cleaner is a device that significantly reduces the jitter component in the input signal by regenerating the input clock using an internal PLL (phase-locked loop).

In addition, it also has functions similar to a clock generator and can perform the following roles:

Multiple clock generation/frequency conversion/clock distribution

This feature makes it possible to supply optimal clocks to multiple devices from a single high-quality clock source.

It is widely used in systems where clock quality is critical, such as FPGAs, SoCs, and high-speed interfaces.

Furthermore, Skyworks' Jitter Cleaner includes a "Holdover" function as a feature (redundancy function) to enhance system reliability.

Holdover is a function that continues to output a clock signal using an internal oscillator and PLL even if the input clock signal is interrupted.

This allows the system to maintain its overall clock supply even if the external clock temporarily stops working.

This feature is particularly useful in environments where clock shutdowns can lead to system failures.

For example, this offers significant advantages in systems that require continuous operation, such as communication infrastructure equipment and medical devices.

Skyworks Jitter Cleaner Product Lineup

The following is a list of Skyworks' jitter cleaner product lineup.
In recent years, the demand for high-precision clock quality has been increasing in data centers, telecommunications infrastructure, broadcasting equipment, industrial equipment, and other applications.
Skyworks' jitter cleaner product line addresses these demands.

Skyworks offers industry-leading low-jitter performance and flexible customization tools.

Below is a list of Jitter Cleaner products.

Introducing Skyworks' Jitter Cleaner

Latest Jitter Cleaner SKY6310x Series

Skyworks' latest jitter cleaner, the SKY6310x series, is a next-generation timing device with ultra-low jitter performance and flexible clock generation capabilities.

It is suitable for generating clocks for high-speed interfaces such as data centers, AI accelerators, and communication equipment.

This series achieves ultra-low jitter performance in the 45 fs class and is compatible with next-generation high-speed interfaces such as PCIe Gen7.

Regarding the model numbering rules, in the SKY6310x series, the number at the end determines the number of outputs and PLLs.

The SKY63101 (PLL:1), SKY63102 (PLL:2), and SKY63103 (PLL:3) have 16 output channels.

The SKY63104 (PLL:1), SKY63105 (PLL:2), and SKY63106 (PLL:3) have 12 output channels.

This jitter cleaner features a spectrum diffusion function, a feature not found in conventional models.

In addition, it can generate PCIe Gen7 compatible clocks, making it suitable for systems requiring high-speed data processing, such as AI accelerator cards and data center servers.

Skyworks' flagship Si539x/SI534x series

Among Skyworks' jitter cleaners, the Si539x and Si534x series are widely used as reference clocks for FPGAs and SoCs.

It has been adopted as a reference design and is used in a wide range of fields, including telecommunications equipment, data center equipment, and industrial equipment.

The difference between the Si534x and Si539x lies in their jitter performance and the number of output wires.

These are Si5392 (2ch), Si5394 (4ch), and Si5395 (12ch) models. The jitter performance is equivalent to 69fs.

These are Si5342 (2ch), Si5344 (4ch), and Si5345 (12ch) models. Jitter performance is equivalent to 100fs.

Furthermore, the Si539x and Si534x are designed to be pin-compatible with each other.

For systems already using Si534x, performance can be improved by replacing it with Si539x without changing the basic design.

This compatibility offers benefits such as improved clock jitter performance, system performance upgrades, and reduced design change risks.

Summary

A jitter cleaner is a timing device that reduces jitter by regenerating the input clock in an internal PLL, resulting in a more stable clock signal.

Furthermore, similar to a clock generator, it features functions such as multiple clock generation, frequency conversion, and clock distribution, making it possible to supply optimal clocks to multiple devices from a single high-quality clock source.

Furthermore, Skyworks' jitter cleaner features a "holdover" function that continues clock output even if the input clock is interrupted.

This feature ensures high reliability in systems such as communication infrastructure equipment and medical devices where clock downtime is unacceptable.

Thus, jitter cleaners have become an important device for ensuring a stable clock supply in modern electronic devices that use high-speed communication and high-performance processors.