For the CERN LHC Run 3, the ALICE experiment completely redesigned the Inner Tracking System, now consisting of seven cylindrical layers instrumented with 24120 Monolithic Active Pixel Sensors, covering a total area of 10 \(m^2\). The readout and powering systems are composed of 192 identical Readout Units (RUs) and 142 Power Boards (PBs) respectively, and have complete control over all sensors operations, including power management, triggering, data readout and slow control. Due to their installation location, the Readout Units and the Power Boards will both operate at about five meters from the interaction point. The expected TID at this location, for the entire detector life cycle, is about 10 kRad (safety factor of 10), while the expected flux of particles with sufficient energy \(>20 MeV\) to induce Single-Event Effects (SEEs) is of the order of \(10^3 cm^-2 s^-1\).
This contribution describes the systems design, focusing on the key requirements and how they have been addressed, and discuss the overall performance achieved.