Fujitsu demos first ADC in family of low-power, high-speed, 28nm CMOS converters

USA: Fujitsu has announced the first in a new family of 8-bit, power-efficient, 28nm CMOS converters. The analog-to-digital converter (ADC) addresses the need for large-scale global deployment of single-wavelength, 100Gbps optical transport systems, and provides a solution for future short-range optical and backplane interconnects.

Now in its third generation of process technology, the 28nm ADC supports sampling rates from 55 to 70 GSa/s (billions of samples per second) with scalable analog bandwidth. The new ADC, which is based on Fujitsu's proven CHAIS architecture, will be shown for the first time at the OFC/NFOEC conference, March 18-21, in Anaheim, California.

Fujitsu will expand the new 8-bit family this year with the release of a digital-to-analog converter (DAC) with the same sampling range. Subsequent ADC and DAC devices, all of which will be available for system design in 2013, will support sampling rates ranging from 28 GSa/s to more than 90 GSa/s. The converters, which can be used in a variety of different channel-count configurations, offer significantly lower power based on sampling rate when compared to previous 40nm CHAIS converters from Fujitsu.

Ever-increasing bandwidth and traffic demands are shifting the requirement for 100Gbps lambdas from the long-haul network (where they run over a few thousand kilometers) to the mid-haul or Metropolitan Area Network (MAN). While distances are shorter in Metro networks (up to a few hundred kilometers), port densities are higher, resulting in mechanical and thermal constraints that require more power-efficient 100Gbps SoC designs.

In addition to their use in 100Gbps long-haul and metro optical transport networks, solutions based on advanced modulation techniques—combined with high-speed, high-resolution low-power converters—can address the increasing bandwidth demands of a number of other sectors.

These include inter- and intra-datacenter optical links for 100Gbps Ethernet, as well as high-speed electrical interconnects across PCB or backplane channels. As in the Metro transport market, increasing bandwidth and traffic demands are pushing high-speed converter designs to be more flexible and power-efficient.