VELA:: The CMOS circuit based on fast current read-out for x-ray Spectroscopy with DePMOS

DePMOS based Active Pixel Sensor (APS) matrix is a new detector concept for X-ray imaging and spectroscopy applications. This tpye of X-ray detector can provide excellent energy resolution and high-speed readout. Both these features and the advantage of random pixel accessibility can fulfill the requirements of new space applications, like the XEUS Wide Field Imager. In a matrix arrangement, each pixel must be read out by a time variant filter, so a new readout mechanism and a proper multi-channel integrated shaping amplifier are needed. To operate at the required fast processing time (e.g., 4 mu s per line) DePMOS transistor cannot be operated in the classical source follower configuration, because this results in a long settling time. So a new design for multi-channel readout of the DePMOS matrix has to be considered. We propose a new fast readout concept, which is based on the DePMOS drain current readout and processing.