Integrated Self-Test Module for Uncorrelated Photon Counting in a Two-Dimensional Array

A 16 × 2 two-dimensional (2-D) array of single-photon avalanche diodes integrated in a complementary metal-oxide-semiconductor (CMOS) process is presented. Each pixel is made up of an avalanche photodiode biased in the so-called Geiger mode, a quenching resistor, and a basic comparator. To implement the photon counting verification on the chip, a build-in-self-test (BIST) module is added. Full integration allows for 10218.70 μm2 of total cell area and 1.7837 mW of power consumption, which is about 38% less than the 2.8567 mW of the prior design. The circuit is capable of running at a 200 MHz counting rate. The array's internal signals and status can be monitored while it is being tested or used thanks to the built-in logic block observation module demonstrated in this paper. The effectiveness and efficiency of testing can be increased, as well as the performance of the readout electronics, by adding Kogge-Stone adder and BIST circuits to the array design. The ability to quickly adapt the design to suit a particular application is another undeniable advantage of CMOS integration, which also paves the way for on-chip data processing.