A Compact Detection Quenching Circuit for Array Single Photon Avalanche Diodes

Abstract

The invention discloses a compact detection quenching circuit applied to an array type single photon avalanche diode, which includes a detection circuit, a gate control circuit, a quenching circuit and a reset circuit with adjustable pulse width. The quenching circuit uses the SPAD junction capacitance to perform I-Q-V integral transformation on the avalanche current generated by the SPAD to convert the current into a voltage signal. After processing by a single-tube comparator, it outputs a pulse signal. The pulse signal is shaped by an inverter. and increase drive capability. On the one hand, the invention can effectively reduce the layout area and circuit transient power consumption, and reduce the power supply requirements of the array SPAD; on the other hand, it can shorten the quenching time, speed up the detection speed, and reduce non-ideal effects; at the same time, the invention adopts an external The capacitive method implements a monostable circuit, which can flexibly adjust the reset pulse width time according to different detector performance.

Description

technical field [0001] The invention relates to a compact detection and quenching circuit applied to an array type single photon avalanche diode, which belongs to the technical field of semiconductors. Background technique [0002] Single photon detection technology is a detection technology based on single photon, which can detect extremely weak light signals, and it is a new detection technology developed in recent years. It can be used in medical diagnosis, astronomical observation, national defense and military, spectral measurement, quantum electronics and other fields. Avalanche Photo Diode (APD) working in Geiger mode is the most widely used single photon detector. [0003] When the APD works in Geiger mode, the reverse bias voltage is higher than its avalanche voltage, and it has extremely high current gain and can detect single photons, so it is called single photon avalanche photodiode (SPAD). When the SPAD senses a single photon, the photon is absorbed in the de...

AI Technical Summary

Problems solved by technology

[0006] 2. In large array applications, the number of pixel circuits increases exponentially, and the increase in power consumption of a single pixel circuit will have a great impact on the entire chip

Most of the existing quenching circuits are designed based on resistance detection. However, the use of passive components such as resistors will expand the layout area and increase transient power consumption, which is not conducive to large-scale integration.

A small number of quenching circuits based on capacitance detection are difficult to apply to arrays due to complex structures, large areas, or problems with charge sharing.

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