This paper describes custom made Low Voltage Power Supply (LVPS) system developed for the ATLAS – TileCal detector of the LHC (The Large Hadron Collider) particle accelerator at CERN, Geneva. The system is based on the use of only COTS (Commercial of The Shelf) components, is qualified to be radiation tolerant up to 40krad, and can operate in external DC magnetic field above 0.02 Tesla. The LVPS design described in this paper has been developed and produced for the ATLAS TileCal detector during the years 2001 – 2007