A Photoelectric Detection Circuit Based on Dual Photodetectors

Abstract

The invention discloses a photoelectric detection circuit based on double photodetectors, which includes a first photodetector and a second photodetector signal processing circuit; the input stage circuit of the signal processing circuit is a differential input circuit; the first photodetector includes The first device area, the first device area of ​​the first photodetector is formed by the collector area of ​​the NPN transistor, the second device area of ​​M first photodetectors is fabricated in the first device area of ​​the first photodetector, M is a natural number less than 10, the second device region of the first photodetector is formed by the base region of the NPN transistor, the structure of the second photodetector is the same as that of the first photodetector; the surface of the second photodetector is covered with Aluminum film. The invention provides a photoelectric detection circuit, whose photoelectric detection sensor is compatible with silicon bipolar integrated circuit technology, and has the beneficial effects of high quantum efficiency and small dark current; and its signal processing circuit has the beneficial effect of being able to suppress external electromagnetic interference.

Description

technical field [0001] The invention relates to a photoelectric detection circuit, in particular to a photoelectric detection circuit based on double photodetectors. Background technique [0002] The single-chip light detection circuit is mainly composed of a photodetector sensor and a transistor amplifier. It converts the weak light signal from the optical path into an electrical signal through the detector, amplifies it through the amplifier, and outputs it after processing. [0003] Generally, the monolithic photodetection circuit has the following advantages: it can reduce the influence of distributed parameters and improve the performance of the device; it saves the interconnection and bonding between photoelectric devices, reduces the volume of the device, and improves the reliability of the device. Due to the above characteristics, advantages and wide application prospects, it has become an important development trend of the output part of the optical coupling device....

AI Technical Summary

Problems solved by technology

[0010] The existing technologies listed above are all compatible with the silicon photodetector and the MOS integrated circuit process, but the prior art still lacks the silicon photodetector and another integrated circuit process, which is also the most mature silicon bipolar circuit. Process compatible technical solutions

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