Prototype Chip for a Control System in a Serial Powered Pixel Detector at the ATLAS Phase II Upgrade

A new inner tracking detector for the Phase-II upgrade of the ATLAS experiment is in development. A serial power scheme is foreseen for the pixel detector. This requires a new detector control system to monitor and control the pixel modules in the serial power chain. The Pixel Serial Power Protection (PSPP) chip is an ASIC for this purpose. It operates parallel to the modules and contains an ADC and bypass transistor. This paper presents test results for the prototyped PSPP chip. It includes irradiation up to 600 Mrad and longterm measurements. The third version of the PSPP chip is functional and will be used for tests with serial power chains together with pixel modules.