A processor for calorimetry at the Large Hadron Collider in the FERMI project

A dedicated digital signal processor has been designed as part of a fully digital front-end for calorimetric detectors developed for experiments in high-energy particle physics to be carried out at CERN with the Large Hadron Collider. Its function is to evaluate the collision energy by analyzing the 16-bits samples (at 67 Msamples per second) contained in a time window through convolutions with 10-bits coefficients. In order to improve the time and amplitude accuracy of the evaluated pulse maximum, we adopted a scheme composed of three inner-product units followed by a sorting circuit which identifies the maximum, the minimum and the median value among the three inner-product outputs. Due to the massively radioactive environment in which the calorimeter operates, the fault tolerance issues have been particularly taken into account to provide both concurrent error detection through residue arithmetic and graceful degradation