Calibrating the Dark Count Rate of Single Photon Avalanche Diodes Using Linear Regression

The Dark Count Rate (DCR) is an inherent characteristic of Single Photon Avalanche Diodes (SPADs). Despite the use of an Active Quenching Active Reset (AQAR) scheme to reduce DCR at the circuit level, the counter connected to the quenching circuit often registers an increase, even in the absence of intended light input. Consequently, an external method is required for accurate calibration of the DCR. This paper proposes the use of linear regression, implemented in a Python program, as a method for such calibration.