An ASIC implementation of digital front-end electronics for a high resolution PET scanner

An application-specific integrated circuit (ASIC) has been designed and fabricated which implements many of the current functions found in the digital front-end electronics for a high-resolution positron emission tomography (PET) scanner. The ASIC performs crystal selection, energy qualification, time correction, and event counting functions for block technology high-resolution PET scanners. Digitized x and y position, event energy, and time information are used by the ASIC to determine block crystal number, qualify the event based on energy, and correct the event time. In addition, event counting and block dead time calculations are performed for system dead time corrections. A loadable sequencer for controlling the analog front-end electronics is also implemented. The ASIC is implemented in a 37000 gate, 1.0 μm CMOS gate-array and is capable of handling 4 million events/s while reducing parts count, cost, and power consumption over current board-level designs