Readout circuit for a silicon photomultiplier (sipm) array using charge sharing and anger logic

Abstract

A method and an apparatus are provided for using a capacitor chain to perform charge sharing and Anger logic to determine, for charge pulses arising from gamma-ray detection, a row position along an array of scintillation-based gamma-ray detectors. Further, high-pass filters configured at the ends of the capacitor chain perform pulse shaping to preserve timing information. To determine the column position for charge pulses, a two-stage summing amplifier configuration is used with weighting amplifiers controlling the relative gain of the second-stage amplifier with respect to respective columns in the array. Each detector element in the array is a silicon photomultiplier (e.g., Geiger-mode avalanched photodiodes biased above breakdown voltage). Position information can be generated by Anger logic on four outputs from the second-stage amplifiers. Energy and timing information can be generated as a sum of the four outputs from the second-stage amplifiers.