Development of CMOS LSI technology for 100Gbit ethernet optical transceivers
Hitachi today announced the successful prototyping of a low-power CMOS gearbox LSI conforming with international standards, which was developed for optical transceivers as part of the effort to reduce power consumption in routers and network equipment to be used in the 100 gigabit (Gbit) Ethernet (henceforth, 100GbE). Optical receivers convert optical signals and electrical signals. The 100GbE CMOS gearbox LSI functions to convert the transmission rate and number of channels, converting the 4 channel × 25 gigabit per second (henceforth, Gb/s) electrical signals received from the network into 10 channels × 10Gb/s electrical signals which can be used within the equipment, and vice versa. Until now, a high-speed gearbox LSI based on SiGe process technology was used for this purpose, however, the achievement of a low-cost and low-power LSI based on the CMOS process was desired. The prototype 100 GbE gearbox LSI fabricated employs the four-phase clock circuit scheme using...