A multipurpose monolithic array of 2 × 2 multichannel digital silicon photomultipliers (MD-SiPMs) fabricated in 40-nm CMOS technology is presented. Each MD-SiPM comprises 64 × 64 smart pixels connected to 128 low-power 45-ps sliding-scale time-to-digital converters (TDCs). The system can operate in two different modes: 1) event-driven and 2) frame-based. The first is suited for positron emission tomography (PET) and the second for synchronous applications like LiDAR. The design includes electronics to capture gamma events by means of a scintillator. The digital readout is fully embedded in the sensor and it is reconfigurable by SPI. Data packets are sent following a simple protocol compatible with an external FIFO, therefore making use of an FPGA optional. Every MD-SiPM can deliver up to 64M time-stamps/s. The sensor can be arranged in any type of configuration through a dedicated synchronization input and can be used to operate jointly with an event generator, such as a pulsed laser, which is useful in many applications. Inherently compatible with 3-D-stacking technology, the sensor can serve as front-end electronics when it is used with a different SPAD silicon tear.

A multipurpose monolithic array of 2×2 multi-channel digital silicon photomultipliers (MD-SiPMs) fabricated in 40nm CMOS technology is presented. Each MD-SiPM comprises 64×64 smart pixels connected to 128 low-power 45ps sliding-scale time-to-digital converters (TDCs). The MD-SiPMs are designed to indirectly capture gamma events in positron emission tomography (PET). The sensor can operate in frame-based and event-driven mode; the latter best suited to capture gamma events. The digital read-out is fully embedded in the sensor and it is reconfigurable by way of serial communication. Data packets are sent following a simple protocol compatible with an external FIFO, therefore eliminating the need of an FPGA. A dedicated input can be used to operate synchronously with an event generator, such as a pulsed laser, useful in other applications, like LiDAR. The system is inherently compatible with 3D-stacking technology; thus serving as a front end for different SPAD technologies, suitable for a variety of applications.