LinoSPAD: a time-resolved 256×1 CMOS SPAD line sensor system featuring 64 FPGA-based TDC channels running at up to 8.5 giga-events per second

Burri, Samuel; Homulle, Harald; Bruschini, Claudio; Charbon, Edoardo

doi:10.1117/12.2227564

Cited by 29 publications

(26 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…SPAD line sensors have been reported targeting other applications, such as near-infrared optical tomography [32], 3D imaging based on time-of-flight measurements [33], laserinduced breakdown spectroscopy [34] and time-resolved Raman spectroscopy [35][36][37][38][39]. Line arrangements of pixels are in general favorable for increasing fill-factor of the sensor, as any additional logic can be placed next to the photon-sensitive area of the pixels.…”

Section: Introductionmentioning

confidence: 99%

Time-resolved spectroscopy at 19,000 lines per second using a CMOS SPAD line array enables advanced biophotonics applications

Kufcsák¹,

Erdogan²,

Walker³

et al. 2017

Opt. Express

View full text Add to dashboard Cite

A SPAD-based line sensor fabricated in 130 nm CMOS technology capable of acquiring time-resolved fluorescence spectra (TRFS) in 8.3 milliseconds is presented. To the best of our knowledge, this is the fastest time correlated single photon counting (TCSPC) TRFS acquisition reported to date. The line sensor is an upgrade to our prior work and incorporates: i) parallelized interface from sensor to surrounding circuitry enabling high line rate to the PC (19,000 lines/s) and ii) novel time-gating architecture where detected photons in the OFF region are rejected digitally after the output stage of the SPAD. The time-gating architecture was chosen to avoid electrical transients on the SPAD high voltage supplies when gating is achieved by excess bias modulation. The time-gate has an adjustable location and time window width allowing the user to focus on time-events of interest. On-chip integrated center-of-mass (CMM) calculations provide efficient acquisition of photon arrivals and direct lifetime estimation of fluorescence decays. Furthermore, any of the SPC, TCSPC and on-chip CMM modes can be used in conjunction with the time-gating. The higher readout rate and versatile architecture greatly empower the user and will allow widespread applications across many techniques and disciplines. Here we focused on 3 examples of TRFS and time-gated Raman spectroscopy: i) kinetics of chlorophyll A fluorescence from an intact leaf; ii) kinetics of a thrombin biosensor FRET probe from quenched to fluorescence states; iii) ex vivo mouse lung tissue autofluorescence TRFS; iv) time-gated Raman spectroscopy of toluene at 3056 cm peak. To the best of our knowledge, we detect spectrally for the first time the fast rise in fluorescence lifetime of chlorophyll A in a measurement over single fluorescent transient.

show abstract

Section: Introductionmentioning

confidence: 99%

Time-resolved spectroscopy at 19,000 lines per second using a CMOS SPAD line array enables advanced biophotonics applications

Kufcsák¹,

Erdogan²,

Walker³

et al. 2017

Opt. Express

View full text Add to dashboard Cite

show abstract

“…An FPGA system indeed offers some flexibility in terms of possible data processing and high computational bandwidth, which can be used for example to realize firmware-based 32×32 autocorrelator arrays as detailed in [49] (with FCS as target application). The "reconfigurable pixel" concept proposed in [35,50] maximizes flexibility by moving the whole circuitry, which is usually placed beyond the basic SPAD pixel structure, inside the FPGA; this makes it possible to implement different TDC or counter architectures, with the goal of tailoring the system (sensor plus firmware) in an optimal way to the target application's needs. Table 2 lists a comprehensive summary of the main SPAD-based sensors and imagers which have been targeted at biophotonics applications; they are discussed in the next section, together with the related applications and the corresponding results.…”

Section: Read-out Architecturementioning

confidence: 99%

Single-photon avalanche diode imagers in biophotonics: review and outlook

et al. 2019

Self Cite

View full text Add to dashboard Cite

Single-photon avalanche diode (SPAD) arrays are solid-state detectors that offer imaging capabilities at the level of individual photons, with unparalleled photon counting and time-resolved performance. This fascinating technology has progressed at a very fast pace in the past 15 years, since its inception in standard CMOS technology in 2003. A host of architectures have been investigated, ranging from simpler implementations, based solely on off-chip data processing, to progressively “smarter” sensors including on-chip, or even pixel level, time-stamping and processing capabilities. As the technology has matured, a range of biophotonics applications have been explored, including (endoscopic) FLIM, (multibeam multiphoton) FLIM-FRET, SPIM-FCS, super-resolution microscopy, time-resolved Raman spectroscopy, NIROT and PET. We will review some representative sensors and their corresponding applications, including the most relevant challenges faced by chip designers and end-users. Finally, we will provide an outlook on the future of this fascinating technology.

show abstract

“…In a raw TDC, large quantization errors are generated since the time intervals between two adjacent TDL taps are largely nonuniform, and only one binary code is processed in each measurement. A compensation approach has been introduced in 2016 to solve this problem, but it was only used for postprocessing, introducing much more processing time especially in multichannel applications [46]. To achieve the fast and direct histogram compensation, we reassigned the fine code to a main bin calibration factor (BCF m ) and a compensation bin calibration factor (BCF c ) when a hit signal is measured.…”

Section: Compensated Histogram and Mixed Calibration Methodsmentioning

confidence: 99%

Multichannel, Low Nonlinearity Time-to-Digital Converters Based on 20 and 28 nm FPGAs

Chen

2019

IEEE Trans. Ind. Electron.

View full text Add to dashboard Cite

This paper presents low nonlinearity, compact, and multichannel time-to-digital converters (TDC) in Xilinx 28 nm Virtex 7 and 20 nm UltraScale field-programmable gate arrays (FPGAs). The proposed TDCs integrate several innovative methods that we have developed: 1) the subtapped delay line averaging topology; 2) tap timing tests; 3) a direct compensation architecture; and 4) a mixed calibration method. The code density tests show that the proposed TDCs have much better linearity performances than previously reported ones. Our approach is cost-effective in terms of the consumption of logic resources. To demonstrate this, we implemented 96 channel TDCs in both FPGAs, using less than 25% of the logic resources. The achieved least significant bit (LSB) is 10.5 ps for Virtex 7 and 5.0 ps for UltraScale FPGAs. After the compensation and calibration, the differential nonlinearity (DNL) is within [-0.05, 0.08] LSB with σDNL = 0.01 LSB, and the integral nonlinearity (INL) is within [-0.09, 0.11] LSB with σINL = 0.04 LSB for the Virtex 7 FPGA. The DNL is within [-0.12, 0.11] LSB with σDNL = 0.03 LSB, and the INL is within [-0.15, 0.48] LSB with σINL = 0.20 LSB for the UltraScale FPGA. Index Terms-Carry chains, field-programmable gate arrays (FPGA), multichannel TDCs, time-of-flight, time-todigital converters (TDC).

show abstract

LinoSPAD: a time-resolved 256×1 CMOS SPAD line sensor system featuring 64 FPGA-based TDC channels running at up to 8.5 giga-events per second

Cited by 29 publications

References 7 publications

Time-resolved spectroscopy at 19,000 lines per second using a CMOS SPAD line array enables advanced biophotonics applications

Time-resolved spectroscopy at 19,000 lines per second using a CMOS SPAD line array enables advanced biophotonics applications

Single-photon avalanche diode imagers in biophotonics: review and outlook

Multichannel, Low Nonlinearity Time-to-Digital Converters Based on 20 and 28 nm FPGAs

Contact Info

Product

Resources

About