A SiPM tile includes SiPM arrays on a detector die, each of the SiPM arrays including a first plurality of microcells and a second plurality of reference microcells dispersed on the die, each reference microcell including an optically-opaque mask, a readout circuit each including a respective charge sensitive amplifier (CSA) connected to one of the reference microcells, each CSA configured to accumulate the dark current of the reference microcell during a selected time window, a hybrid temperature control circuit configured to receive an output signal from each CSA, and to determine the real-time temperature of the die based on the received output signal, to provide the real-time temperature to a temperature compensation and correction control unit that adjusts a cooling/heating system flow provided to the die, the adjustment based on the real-time temperature. A method for compensating the operating temperature variation of the SiPM tile is also disclosed.

Silicon photomultiplier circuitry is provided that comprises at least one silicon photomultiplier pixel, each pixel comprising a plurality of silicon photomultiplier microcells. The silicon photomultiplier circuitry comprises control circuitry adapted to maintain a substantially constant voltage on a connection node between microcells of the pixel. The control circuitry is adapted to minimize the onset and recovery time of an output signal by maintaining a substantially constant voltage on the connection node.

A diode and a transistor are connected in parallel. The transistor is located on a first doped region forming a PN junction of the diode with a second doped region located under the first region. The circuit functions as an ionizing radiation detection cell by generating a current through the PN junction which changes by a voltage generated across the transistor. This change in voltage is compared to a threshold to detect the ionizing radiation.

The present disclosure relates to devices, systems, and methods relating to configurable silicon photomultiplier (SiPM) devices. An example device includes a substrate and a plurality of single photon avalanche diodes (SPADs) coupled to the substrate. The device also includes a plurality of outputs coupled to the substrate and a plurality of electrical components coupled to the substrate. The plurality of electrical components are configured to selectively connect the plurality of SPADs to the plurality of outputs by selecting which output of the plurality of outputs is connected to each SPAD of the plurality of SPADs and to thereby define a plurality of SiPMs in the device such that each SiPM of the plurality of SiPMs comprises a respective set of one or more SPADs connected to a respective output of the plurality of outputs.

A chip-to-chip integration process for rapid prototyping of silicon avalanche photodiode (APD) arrays has been developed. This process has several advantages over wafer-level 3D integration, including: (1) reduced cost per development cycle since a dedicated full-wafer read-out integrated circuit (ROIC) fabrication is not needed, (2) compatibility with ROICs made in previous fabrication runs, and (3) accelerated schedule. The process provides several advantages over previous processes for chip-to-chip integration, including: (1) shorter processing time as the chips can be diced, bump-bonded, and then thinned at the chip-level faster than in a wafer-level back-illumination process, and (2) the CMOS substrate provides mechanical support for the APD device, allowing integration of fast microlenses directly on the APD back surface. This approach yields APDs with low dark count rates (DCRs) and higher radiation tolerance for harsh environments and can be extended to large arrays of APDs.

A panel radiation detector is provided for detecting radiation event(s) of ionizing radiation, comprising a plurality of adjoining plastic scintillator slabs, a plurality of silicon photomultiplier sensors arranged at an edge of at least one of the plastic scintillator slabs) and configured to detect scintillation light generated in the scintillator slabs responsive to the radiation events, and a plurality of signal processing units each connected to one of the silicon photomultiplier sensors, wherein the signal processing units each comprise a digitization circuit configured to generate a digitized signal for signal analysis by executing 1-bit digitization of a detection signal generated by at least one of the silicon photomultiplier sensors responsive to the detected scintillation light for determining the energy of the detected radiation event(s).

In an embodiment, a method includes: providing a gray-coded time reference to a time-to-digital converter (TDC); receiving an event from an event signal; latching the gray-coded time reference into a memory upon reception of the event signal; and updating a time-of-flight (ToF) histogram based on the latched gray-coded time reference.

Disclosed herein is a radiation detector, comprising: an avalanche photodiode (APD) with a first side coupled to an electrode and configured to work in a linear mode; a capacitor module electrically connected to the electrode and comprising a capacitor, wherein the capacitor module is configured to collect charge carriers from the electrode onto the capacitor; a current sourcing module in parallel to the capacitor, the current sourcing module configured to compensate for a leakage current in the APD and comprising a current source and a modulator; wherein the current source is configured to output a first electrical current and a second electrical current; wherein the modulator is configured to control a ratio of a duration at which the current source outputs the first electrical current to a duration at which the current source outputs the second electrical current.

Systems and methods include an analog-to-logic circuit and a digital processing component. The analog-to-logic circuit receives a first electrical signal, outputs a first logic signal indicating whether or not a voltage of the first pulse is greater than a first threshold voltage, and outputs a second logic signal indicating whether or not the voltage of the first pulse is greater than a second threshold voltage. The digital processing component receives the first logic pulse and the second logic pulse, determines, based on the second logic signal, if the first pulse is valid, and determines, based on the first logic signal, a first trigger time associated with the first pulse.

Methods and systems are provided for signal processing in a detector assembly of an imaging system. In one embodiment, an imaging system may include a plurality of detector blocks, each detector block including an array of silicon photomultiplier (SiPM) devices divided into at least two regions, with the SiPM devices in the two or more regions transmitting signals to two or more distinct timing pick-off circuits. In this way, a SiPM array may be subdivided into regions with a signal summed from SiPMs of a single region being transmitted to a separate timing pick-off circuit.