Miniature low phase jitter SPXOs meet optical comms modules needs
Designed for small, optical communications modules that support 400G, the SG2520 simple packaged crystal oscillators (SPXOs) are 44 per cent smaller than Epson’s earlier products.
The series of differential output SPXOs achieve low phase jitter in the fundamental mode. They are supplied in a miniature 2.5 x 2.0 x 0.74mm package. Epson has added the SG2520EGN, SG2520EHN, SG2520VGN and SG2520VHN. All are claimed provide improved frequency stability.
As telecommunications network traffic and capacity increases in response to the introduction of 5G telecommunications systems and the evolution of mobile networks, the IoT, advanced driver assistance systems (ADAS), and data centres. The noise level permissible in communication signals is lower, while clocks used in network equipment must operate at high-frequency and have low phase jitter. As a result, optical communication modules connect network devices are becoming faster and smaller, and clocks with a frequency tolerance of ± 20 x 10-6 or less are needed for transmissions at ultra-high speeds of 400 and 800Gbits per second and distances of 80km or more.
The SG3225EEN and SG3225VEN SPXOs offer frequencies up to 500MHz and low phase jitter. They are equipped with a compact oscillator IC developed by Epson that compensates the temperature co-efficient of frequency of the built-in high-frequency fundamental (HFF) crystal oscillator. The use of this IC enabled Epson to shrink the footprint of the SPXOs by 63 per cent and their cubic volume by 44 per cent compared to earlier products, says the company. They demonstrate frequency stability, with a frequency tolerance at -40 to +105˚C that is half that of the predecessor (SG2520EGN and SG2520VGN) and 40 per cent in the case of SG2520EHN and SG2520VHN. The SPXOs are suitable for network equipment (e.g. routers, switches, optical modules), data centres, factory automation equipment, measuring instruments and high-speed DACs and ADCs.
Epson has begun shipping SPXOs with frequencies up to 212.5MHz. Epson plans to begin volume production of SPXOs in frequencies from 212.5 to 500MHZ in March 2021.