An optical link interface for the Tile-Calorimeter in ATLAS

The new LHC particle accelerator now being built at CERN will have a radically increased event rate and higher energy. To accommodate this, instrumentation for LHC experiments has had to be constructed using new ideas and the latest available technology. A part of this effort was the development and test of a digitizer unit for the hadron calorimeter (TileCal) of the ATLAS experiment. To try out ideas and promote system integration, prototypes were tested in a subsystem using a particle beam to simulate the final conditions. During the development of these prototypes an application-specific integrated circuit was constructed to control the digitizer system. Tests made at the test beam facility have verified that all requirements were met. The final digitizer design and its components were radiation tested to verify full functionallity in its radiation environment during the full ATLAS life-span. Test devices were also constructed to test all production units. In addition to the digitizer system, an optical readout link was designed to meet the requirements for the digitizer readout. Preliminary studies indicate that the digitizer could also be used in an upgraded LHC, with presently considered scenarios.