Rpol2v5: a Compact Radiation-Hard Resonant Switched-Capacitor DC-DC Converter for the CMS HGCAL

A radiation-tolerant resonant switched-capacitor DC-DC converter (rPOL2V5) has been developed to supply the front-end analog and digital circuits for the detectors used in the LHC High Luminosity upgrades. It has been of particular interest to the CMS High-Granularity Calorimeter (HGCAL) community due to its lower volume compared to existing radiation-hard buck converters. rPOL2V5 is based on an ASIC developed using 130nm CMOS technology. It is powered by a 2.5V input and it can supply a maximum current from 2A to 5 A, depending on the output voltage value, which can range from 1V to 1.5V. This work presents the strategies adopted at the ASIC and PCB level to bring the converter to maturity, and its electrical and radiation characterisation results.