A 10 bit analog counter in SPAD pixel

Abstract

An improved active-quenching circuit and a linear counting circuit used for a silicon single photon avalanche diode (SPAD) are presented in this paper. The proposed quenching circuit is fast and compact. The linear counting circuit can achieve 10 bit large count range with a small capacitor, which can effectively reduce the area of pixel. Due to the significant advantages of low-cost, compactness and high count range, the two pixel circuits are very suitable for the high density SPAD array detector.