The Si534xH coherent optical clocks have been designed to replace discrete timing solutions that rely on expensive, large-footprint voltage-controlled SAW oscillators (VCSOs) to provide low-jitter reference timing for data converters. Unlike VCSOs that support single, fixed frequencies, the Si534xH clocks are able to operate over a wide frequency range, supporting frequencies up to 2.7 GHz without the need to change bill-of-material (BOM) components.
The Si5344H and Si5342H clocks combine frequency flexibility with improved jitter performance of 50 fs RMS. The devices simplify component sourcing, replacing multiple custom, long-lead time VCSOs with a clock IC solution available with short, two-week lead times. Featuring a jitter-attenuating PLL, high-frequency output drivers, fractional frequency synthesis and digitally controlled oscillator (DCO) technology, these devices are able to provide all the clocking functions required for coherent optical transceiver applications while enabling a 40 percent smaller footprint and 40 percent lower power than competing solutions, according to the company.
These new devices look to address one of the largest growth drivers in the communications market - the industry's transition from 10G to 100G in metro area networks and data center interconnect (DCI). Coherent optics is an enabling technology for 100G and 400G applications because it allows service providers to send more data over existing optical fibre, reducing the cost and complexity of network upgrades for bandwidth expansion.
Current timing solutions for coherent optics are not optimised for cost or size, requiring a diverse mix of VCSOs, clock generators and discrete components.
The Si534xH clocks are purpose-built to address the timing requirements of 100G/400G coherent optics and, in addition, are able to support the ultra-high frequency synthesis necessary for clocking optical transceiver data converters.
All 100G/400G transmitter or receiver clocks can be generated by a single device, minimizing BOM cost and complexity by eliminating the need for numerous discrete components.
