A Boosted Active Quenching Circuit with Detector Capacitance Compensation

The detector capacitance compensation (DCC) technique which achieves double active quenching of single-photon avalanche diode (SPAD) is presented in this paper. A well-defined active quenching circuit has the advantages of a higher maximum photon-counting rate and lower afterpulsing probability. Quenching time and area are important criteria when implementing an active quenching circuit. The proposed novel active quenching circuit employing the DCC technique achieves 2.5 times better quenching time than the conventional one, with an area increase of just 23%. The schematic and simulation results are shown in this paper. Designed circuits are fabricated and simulated in 180 nm CMOS technology.