# US 10,760,960 B2 · Coincidence resolving time readout circuit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,760,960 B2 - Document ID: US10760960B2 - Status: Granted - Kind: B2 - Application number: 15/456,136 - Filed: 2017-03-10 - Published: 2018-09-13 - Granted: 2020-09-01 - Earliest claimed: 2017-03-10 - Assignees: SensL Technologies Ltd. - Applicants: SensL Technologies Ltd. - Inventors: Salvatore Gnecchi; John Carlton Jackson; Edoardo Charbon - Web page: https://patentgrep.com/patent/US10760960B2 ## CPC - G01J 1/44: Electric circuits {(for command of an exposure part G03B7/02)} - G01T 1/2985: {In depth localisation, e.g. using positron emitters; Tomographic imaging (longitudinal and transverse section imaging; apparatus for radiation diagnosis sequentially in different planes, steroscopic radiation diagnosis); (using external radiation sources A61B6/02)} - H10F 30/225: the potential barrier working in avalanche mode, e.g. avalanche photodiodes - H10F 39/803: {Pixels having integrated switching, control, storage or amplification elements} - G01J 2001/442: {Single-photon detection or photon counting} - G01J 2001/4466: {Avalanche} - G01J: MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY (light sources F21, H01J, H01K, H05B; investigating properties of materials by optical means G01N) - G01T: MEASUREMENT OF NUCLEAR OR X-RADIATION (radiation analysis of materials, mass spectrometry G01N23/00; tubes for determining the presence, intensity, density or energy of radiation or particles H01J47/00) - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION ## Abstract A coincidence resolving time readout circuit is described. An analog SiPM sensor for detecting photons and generating an SIPM output signal is provided. An ADC is configured to provide multiple threshold values for converting the analogue SiPM output signal to digital values. A time to digital converter configured to receive multiple digital values from the ADC and timestamp the digital values. ## Claims ### Claim 1 A coincidence resolving time (CRT) readout circuit comprising: an analog SiPM sensor for detecting photons and generating an analog SiPM output signal, said analog SiPM sensor comprising a summed array of Geiger mode photodiodes electrically connected to a common electrode, wherein outputs of the Geiger mode photodiodes are summed to form the analog SiPM output signal on the common electrode; an ADC for converting the analog SiPM output signal to digital values according to corresponding ones of multiple threshold values; and a time to digital converter configured to receive the digital values from the ADC and timestamp them. ### Claim 2 (depends on 1) The CRT readout circuit as claimed in claim 1, further comprising an amplifier for amplifying the analog SiPM output signal in advance of the analog SiPM output signal being received by the ADC. ### Claim 3 (depends on 1) The CRT readout circuit as claimed in claim 1, wherein the ADC is a flash ADC. ### Claim 4 (depends on 1) The CRT readout circuit as claimed in claim 1, wherein the ADC is configured to have a voltage range. ### Claim 5 The CRT readout circuit as claimed in 4, wherein the voltage range is determined based on a plurality of parameters. ### Claim 6 (depends on 5) The CRT readout circuit as claimed in claim 5, wherein at least one of the parameters is associated with a parameter of a CRT application. ### Claim 7 (depends on 5) The CRT readout circuit as claimed in claim 5, wherein at least one of the parameters is associated with a characteristic of a scintillator. ### Claim 8 (depends on 5) The CRT readout circuit as claimed in claim 5, wherein at least one of the parameters is associated with a characteristic of a laser pulse shape. ### Claim 9 (depends on 5) The CRT readout circuit as claimed in claim 5, wherein at least one of the parameters is associated with a bandwidth of an amplifier. ### Claim 10 (depends on 5) The CRT readout circuit as claimed in claim 5, wherein at least one of the parameters is associated with a dynamic range of the analog SiPM sensor. ### Claim 11 (depends on 5) The CRT readout circuit as claimed in claim 5, wherein at least one of the parameters is associated with system jitter. ### Claim 12 (depends on 5) The CRT readout circuit as claimed in claim 5, wherein the voltage range of the ADC is used to set an ADC resolution in addition to a plurality of predefined CRT algorithm requirements. ### Claim 13 (depends on 1) The CRT readout circuit as claimed in claim 1, wherein a number of timestamps from the time to digital converter is sufficient to reach an ideal Cramer limit. ### Claim 14 (depends on 1) The CRT readout circuit as claimed in claim 1, wherein all the number of timestamps from the time to digital converter feed dedicated algorithms proven to reach minimum CRT values. ### Claim 15 (depends on 1) The CRT readout circuit as claimed in claim 1, wherein the analog SiPM sensor is a single-photon sensor. ### Claim 16 (depends on 1) The CRT readout circuit as claimed in claim 1, wherein the analog SiPM sensor comprises a matrix of micro-cells. ### Claim 17 A coincidence resolving time readout circuit comprising: an analog SiPM sensor for detecting photons and generating an analog SiPM output signal on an output thereof, said analog SiPM sensor comprising a summed array of Geiger mode photodiodes electrically connected to a common electrode, wherein outputs of the Geiger mode photodiodes are summed to form the analog SiPM output signal on the common electrode; an ADC having an input coupled to the output of the analog SiPM sensor, and a plurality of outputs, wherein the ADC converts the analog SiPM output signal to a plurality of digital values provided to corresponding ones of the plurality of outputs according to corresponding ones of multiple threshold values; and a time to digital converter having a plurality of inputs coupled to the plurality of outputs of the ADC, and a plurality of outputs for providing a plurality of timestamps corresponding to the plurality of digital values. ### Claim 18 (depends on 17) The coincidence resolving time readout circuit of claim 17, further comprising an amplifier having an input coupled to the output of the analog SiPM sensor, and an output coupled to the input of the ADC. ### Claim 19 (depends on 17) The CRT readout circuit of claim 17, wherein the ADC is a flash ADC.