Analysis of Avalanche Signal Recovery in Sinewave Gated High Speed Single Photon Detectors

A Single Photon Avalanche Diode (SPAD) can detect a single-photon if the reverse bias is greater than the breakdown voltage. In a time-gated SPAD the bias rises above the breakdown voltage only when a photon is expected. The frequency of the gating signal can be configured depending on the detection speed requirement. The benefits of time-gated operation include faster detector response times and low after-pulsing effect. However, this mode of operation also requires to recover the avalanche signal that can be lost in the capacitive response of the SPAD. Numerous techniques have been developed in the past to solve this issue, in this paper we present the impact of the recovery techniques on the avalanche signal in a sinewave gated high speed SPAD. The measurement results show that Chebyshev low-pass filter distorts the avalanche pulse, whereras the signal remains undistorted when using destructive interference.