The ARAGORN front-end - An FPGA based implementation of a Time-to-Digital Converter

We present the ARAGORN front-end, a cost-optimized, high-density Time-to-Digital Converter platform. Four Xilinx Artix-7 FPGAs implement 384 channels with an average time resolution of 165 ps on a single module. A fifth FPGA acts as data concentrator and generic board master. The front-end features a SFP+ transceiver for data output and an optional multi-channel optical transceiver slot to interconnect with up to seven boards though a star topology. This novel approach makes it possible to read out up to eight boards yielding 3072 input channels via a single optical fiber at a bandwidth of 6.6 Gb/s.