Commissioning of ROD boards for the entire ATLAS Pixel Detector

The ATLAS Experiment has reworked and upgraded some electronic DAQ chains during the 2013–2015 LHC shut down and an additional barrel layer has been inserted as part of the Pixel Detector: the Insertable B-Layer (IBL). The Layers 2 and 1 of the ATLAS Pixel Detector have also been upgraded, using the same Back Of Crate (BOC) and ReadOut-Driver (ROD) cards designed for IBL, while maintaining the front-end sensors unchanged. The two layers 2 and 1 are mentioned in the order that they have been upgraded, so Layer 2 first and then Layer 1, according to the bandwidth limitation as a function of the luminosity. Now the efforts focus on upgrading DAQ electronics of the B-layer and the Disks, again leaving the front-end detectors untouched. The Layer 2 and 1, which required 26 and 38 additional pairs of IBL BOC and ROD cards, have been taken data during 2017. The IBL boards can easily expand the bandwidth of the Pixel Layer 2 and 1 since a dedicated firmware has been provided to interface with the old detector. In particular, these layers read out the FE-I3 ASICs instead of the IBL FE-I4 chips. The same IBL BOC and ROD card configuration has been used for the upgrade of the B-Layer and Disks of the ATLAS Pixel Detector. In addition, the B-Layer and Disks share the same firmware in use for Layer 1 readout. The additional RODs have already been produced and tested. The plan was to have the readout upgrade of B-Layer and Disks commissioned by the first technical stop in January-March 2018. Thus, eventually, the entire Pixel Detector of ATLAS will share the same hardware readout chain, but the firmware will depend on the type of front-end sensor and modularity.