The optimization, design and performance of the FBCM23 ASIC for the upgraded CMS beam monitoring system

Abstract: We present the development of the FBCM23 ASIC designed for the Phase-II upgrade of the Fast Beam Condition Monitoring (FBCM) system built at the CMS experiment which will replace the present luminometer based on the BCM1F ASIC [1]. The FBCM system should provide reliable luminosity measurement with 1ns time resolution enabling the detection of beam-induced background. The FBCM23 ASIC comprises 6 channels of the fast front-end amplifier working in transimpedance configuration, booster amplifier, and leading edge discriminator. The complete processing chain provides an overall shaping function equivalent to the CR-RC$^3$ filter. The paper will show the optimization of the design, overall architecture, and the detailed implementation in a CMOS 65nm process as well as preliminary electrical performance.