Performance of FlexToT time based PET readout ASIC for depth of interaction measurements

Abstract

The FlexToT ASIC, a read-out electronics for Positron Emission Tomography (PET), has been developed using novel technology, inherited from the field of High Energy Physics (HEP). Using a novel current input stage and a linearized Time over Threshold (ToT) design the FlexToT electronics obtains results within the requirements of the PET technology with simpler and more robust system and using less power consumption. In this work, the capability of the developed ASIC to resolve depth of interaction (DOI) in PET detectors is tested. Results obtained using an implementation of phoswich detector with two crystals, a GSO and LYSO, show a 99% of correct identification rate for separated crystals. Measurements with stacked crystals are currently in progress. Preliminary results with this configuration are encouraging.