A radiation tolerant read-out link and control Daughterboard for the upgrade the of the ATLAS Hadronic Calorimeter.

A radiation tolerant read-out link and control Daughterboard for the upgrade the of the ATLAS Hadronic Calorimeter. This paper summarizes the design strategies and results of the radiation studies of the ATLAS Tile Calorimeter (TileCal) read-out link and control Daughterboard for the High Luminosity Large Hadron Collider (LHC). A total of 896 Daughterboards will interface the on- and off-detector electronics through 5376 optical multi-Gbps links powered by CERN radiation hard GBTx ASICs, Microsemi ProASIC FPGAs and Xilinx Kintex Ultrascale FPGAs. Each Daughterboard receives configuration commands, while recovering and phase adjusting LHC synchronized clocks that drive multiple sampling ADCs in the front-end. Simultaneously, continuous high-speed readout of digitized PMT samples, slow control and monitoring data is sent to the off-detector. Different variants of commercial off-the-shelf components have been studied under radiation to be qualified for the radiation levels simulated for the entire HL-LHC lifetime. Additionally, the design minimizes possible single points of failure induced by sensitivity to radiation damage by employing a double-redundant scheme, implementing Triple Mode Redundancy in the firmware designs, enabling the Xilinx Soft Error Mitigation solution in the Kintex FPGAs, and using Forward Error Correction (FEC) in all the links