A novel low noise mixed signal switched CMOS readout chain for imaging-spectroscopic pixel X-ray detectors

Abstract

A novel CMOS charge sensitive readout chain with self switched output for pixel applications has been developed. The system is capable of simultaneous position sensing and energy measurement on a real time basis. Each pixel circuitry incorporates both analog and digital features to perform the dual task. The pixel electronics have been designed and fabricated in CMOS 0.8 /spl mu/m technology. Noise evaluation of several charge amplifiers as input stages has been performed and reported. The overall gain of the chain is 620 mV/fC. With an ENC of 58 e/sup -/ RMS at 140 nsec shaping time and a power consumption of 1.8 mW per pixel at 3.3 V it is a promising solution for X-ray pixel detectors. The paper describes the system architecture and reports experimental measurements.