Design Of Periodic Regulation Mode Linear Array Readout Circuit For Photon Detection Imaging

Photon detection imaging technology uses a detector with single photon detection ability to collect and transform the light information of the target scene.Then the signal is preprocessed by the readout circuit.Finally,the image information of the target scene is restored by the imaging system.The technology not only has great strategic significance in military visual navigation,warship communications and other areas of national defense security,but also has important application value in high-voltage corona inspection,medical imaging diagnosis and other commercial and civil fields for single photon sensitivity,low background noise interference and high detection accuracy.However,with the continuous in-depth study of contemporary detection technology and information processing technologies,higher requirements have been placed on the effective detection rate,detection accuracy,and functional diversity of detection systems.In order to meet the application requirement of photon counting detection imaging based on APD detector,a periodic regulation mode linear array readout circuit system is proposed,which can accurately detect the photon intensity information in the scene of wide dynamic range random distribution of light intensity.The readout circuit periodically suppresses the non-ideal factors such as the dark count of the detector while ensuring a high effective detection rate of the detector and the dead time is short.This method effectively reduces the false alarm rate of the detection system.According to the target detection scene performance requirements of the detection system,the circuit system can also select two different periodic regulation mode.The effective detection rate of the periodic reset mode is higher than the cycle-off reset mode,and the cycle-off reset mode suppresses the dark count effect better under the same detection conditions.Each periodic regulation mode has three adjustment cycle gears to choose from,and the smaller the adjustment cycle,the lower the system false alarm rate.On this basis,the working mode,system architecture and control timing of the readout circuit system are designed to complete the design of each circuit module and the layout of the pixel array.Using TSMC 0.35?m CMOS technology and Cadence and other EDA software,the pre-simulation verification and optimization of the circuit system,the layout design and layout wiring,and the postsimulation of the main modules to extract the parasitic parameters are completed.The array size is 1×8,and the total area of the circuit is 2186?m×1854?m.The simulation results meet the design requirements.The test results show that the standard operating frequency of the detection system is 20 MHz,the dynamic range of counting is 54.18 dB,the dead time adjustable range is 100ns~500ns,the adjustment period has three gears,32 bit,64bit and 128 bit,respectively.The power consumption is 3.29 mW,the effective detection rate is higher than 72.28% and the system false alarm rate is less than 22.41%.The chip test results show that the effective detection rate and detection accuracy of the detection system could be improved by periodic regulation function,and the overall performance of the detection system can be improved.The detection effect is good for the photon intensity information in the target scene.