ATLAS calorimeter and topological trigger upgrades for Phase 1

The ATLAS Level-1 Calorimeter Trigger (L1Calo) collaboration is pursuing two hardware upgrade programs for Phase 1 of the LHC upgrade. The first of these is development of a new mixed-signal multi-chip module (MCM) for the PreProcessor system. based on faster FADCs and a modern FPGA. Designed as a drop-in replacement for the existing MCM, the FPGA also enables future upgrades to the PreProcessor algorithms, including enhanced digital filtering and compensation for time-variation of pedestals. It is also planned to augment the current multiplicity-based trigger by adding topology-based algorithms. This is made possible by adding jet and EM/hadron Regions of Interest (ROIs) to the L1Calo real time data path. A synchronous, pipelined topological processor (TP) based on high-density FPGAs and multi-Gbit optical links gathers all ROI information and performs topological algorithms.