ATLAS pixel radiation monitoring with the high voltage delivery system

We describe the principles of radiation damage monitoring using current measurement of the pixel sensors to be provided by the circuits of ATLAS Pixel Detector high voltage delivery (HVPP4) system. The dependence of the leakage current upon the integrated luminosity for several temperature scenarios is presented. Based on the analysis we have determined the sensitivity specifications for a Current Measurement System under development at the University of New Mexico, USA and CERN. The status of the development is presented as well, and some characteristics of the prototype system are shown.