A 1.25Gbit/s serializer for LHC data and trigger optical links

Several LHC detectors require high-speed digital optical links for data transmission in both data readout and trigger systems. Commercial components can be found that meet the bandwidth requirements of most of the LHC detectors subsystems. However, they fail to meet some of the requirements frequently encountered in the LHC-HEP environment, namely: resistance to high radiation doses and operation tolerant to single event upsets. To address these problems, a high-speed transmitter ASIC (1.2Gbit/s), containing a serializer and a clock multiplying PLL was developed. The prototype was implemented in a mainstream 0.25um CMOS technology and was designed using well-established radiation tolerant layout practices to achieve resistance to high radiation doses. This implementation serves as a base for the development of radiation tolerant IC's that will make feasible the transmission of data using common local area networks protocols in typical LHC radiation hard environments. The ASIC was embedded in a test setup that uses a commercial optical receiver and de-serializer. Error free data transmission at 1.2Gbit/s was achieved proving the prototypes to be fully functional.