The power supply system of the AMS-02 tracker detector

This paper describes the architecture, the performance and the qualification tests of the tracker detector power supply system for the AMS-02 experiment. The AMS-02 experiment will measure the cosmic ray spectrum from 0.5 GeV up to several TeV in space, looking for anti-matter, dark matter and strange quark matter. The experimental apparatus will be installed in the International Space Station (ISS) in year 2008. A preliminary version of this experiment has flown in 1998 on the STS-91 shuttle flight. The power supply system of the tracker has been designed optimizing noise performances, modularity and efficiency. Power is generated starting from a 28 V line coming from the power distribution box for the entire experiment. This power is converted into the needed voltages by means of DC-DC converters, and for bias supply and front-end voltages is postregulated by means of linear regulators. Components off the shelf (COTS) have been extensively used in the construction of this power supply, however various radiation test campaigns have been performed in order to verify the reliability of these components. Active components were tested for total dose radiation damage and digital components were also tested for single event effects. The power supply architecture developed for the tracker detector has been used as a guideline for the development of the power supplies for the other detectors in the experiment.