Upgrade of the ATLAS Tile Calorimeter High Voltage system

The high voltage (HV) system of TileCal, the ATLAS central hadron calorimeter, needs to be upgraded for the HL-LHC, in the so called Phase II Upgrade. In the proposed solution for the upgrade the HV regulation boards are not located inside the detector anymore, they are deployed far from the radiation in a room where there is permanent access for maintenance. This option requires a large number of 100 m long HV cables but removes the requirement of radiation hard boards. HVremote regulation boards have been developed and tested. Preliminary results of the performance will be presented.