Readout board upgrade for the Pixel Detectors: reasons, status and results in ATLAS

The increase of luminosity in the LHC accelerator at CERN constitutes a challenge for the data readout since the rate of data to be transmitted depends on both pileup and trigger frequency. In the ATLAS experiment, the effect of the increased luminosity is most evident in the Pixel Detector, which is the detector closest to the beam pipe. In order to face the difficult experimental challenges, the readout system was upgraded during the last few years. The main purpose of the upgrade was to provide a higher bandwidth by exploiting more recent technologies. The new readout system is composed by two paired electronic boards named Back Of Crate (BOC) and ReadOut Driver (ROD). In this work the main readout limitation related to increased luminosity will be discussed as well as the strategy and the technological solutions adopted in order to cope with the future operational challenges. In addition the general progresses and achievements will be presented.