Design and test of current-mode DACs for threshold tuning of front-end channels for the High Luminosity LHC

This work is concerned with the design and the characterization of digital-to-analog current converters, developed in a 65 nm CMOS technology, conceived for threshold tuning of front-end channels at the High-Luminosity LHC experiment upgrades. Two DAC structures were integrated in a small prototype chip, that was submitted in August 2018 in the framework of the RD53 developments. The prototype has been tested before and after exposure to X-rays up to a TID of 460 Mrad(SiO2). The main performance parameters of the two structures are compared and discussed in the paper.