A CANopen based prototype chip for the Detector Control System of the ATLAS ITk Pixel Detector

The ATLAS collaboration will install a new inner tracker (ITk) during the phase II upgrade. The innermost part will be a pixel detector. A new Detector Control System (DCS) is being developed to provide control and monitoring of the ITk pixel detector. The MoPS is a CANopen based Application Specific Integrated Circuit foreseen to independently monitor a serial power chain. The final chip is required to be radiation hard up to an ionizing dose of 500 Mrad. This paper focuses on the feasibility of combining low supply voltage custom ASICs found in radiation detection applications and commercial CAN bus equipment. It proposes a CAN physical layer which is operated at 3.6 V and intended to drive a CAN bus of 60 m length at a data rate of 125 kbit/s. In addition voltage regulators with an input voltage of 5 V, output voltages of 3.6 V, 2.4 V and 1.2 V and a load current capability of 200mA have been developed to power the chip via the CAN bus.