Challenges and Performance of the Frontier Technology Applied to an ATLAS Phase-I Calorimeter Trigger Board Dedicated to the Jet Identification

The ‘Phase-I’ upgrade of the Large Hadron Collider (LHC), scheduled to be completed in 2021, will lead to an enhanced collision luminosity and an increased number of interactions per LHC bunch crossing. To cope with the new and challenging accelerator conditions, all the CERN experiments have planned a major detector upgrade to be installed during the associated experimental shutdown period. One of the physics goals of the ATLAS experiment is to maintain sensitivity to electroweak processes despite the increased event rate. To this end, the first-level hardware trigger based on calorimeter data will be upgraded to exploit fine-granularity readout using a new system of Feature EXtractors (FEXs), which each uses different physics objects for trigger selection. There will be three FEX systems in total, the electron, the jet and the global Feature Extractor. This contribution focuses on the first prototype of the jet FEX (jFEX) and presents the hardware design challenges and adopted solutions to preserve signal integrity within a densely populated high signal speed ATCA board.