Analog ASICs for a depth of interaction (DOI) positron emission tomography (PET) detector module

An analog electronics system is designed for a DOI PET detector module. The system includes two ASIC chips: energy/timing and winner-select-output (WSO). A four-channel energy/timing ASIC chip is designed and evaluated. The ASIC integrates pre-amplifier, gain-adjustment, baseline restore, gated-integrator, timing generation, energy-ok check, sample and hold, output buffering and digital control into one chip. Investigation has been done to solve the baseline restore and digital noise-coupling problems. A 16-channel WSO ASIC is designed to determine the maximum signal and its partner from 16 analog inputs. The chip also outputs the digital addresses of the selected signals. The WSO ASIC is sensitive to a 10 mV difference while maintaining low power and high speed. Both the energy/timing and WSO ASIC were sent to MOSIS for fabrication. Both ASIC chips work and will be used to build the front-end analog electronics system for a DOI PET detector module.