ICARUS ASIC: a 16 channel photodiode read out system

In the frame of the INTEGRAL satellite, the second medium size mission of the ESA Horizon 2000 plus plan, it is required that the gamma-ray detector of IBIS, one of the on board instrument, exhibits position sensitive capabilities. This detector will be realised in two different planes, the top one sensitive to 10-1,000 keV and the bottom one operative from 100 to 10,000 keV. Although realised with different technologies (solid state and scintillator detectors), the two planes adopt the same philosophy for position sensitive evaluation. They will be assembled using arrays of independent detectors (the pixels) whose size will determine the position resolution of the instrument. In this approach each pixel will need its individual electronic chain. To fulfil the constraints of space and power available for the project, these electronic chains can only be realised using ASIC technology. This work describes the ICARUS ASIC used to read-out the signals delivered by photodiodes employed into the high energy plane of IBIS instrument