Circuit carrying out temperature compensation on bias voltage of avalanche photodiode

Abstract

The invention discloses a circuit carrying out temperature compensation on the bias voltage of an avalanche photodiode, comprising a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a potentiometer, a negative temperature coefficient thermosensitive resistor, a voltage-regulator tube, a first crystal triode and a second crystal triode. In the circuit, a thermosensitive resistor feedback sampling part is formed by the first resistor, the second resistor, the potentiometer, the negative temperature coefficient thermosensitive resistor and the third resistor; a reference voltage part is formed by in series connecting the fourth resistor with the voltage-regulator tube; and a comparison and amplification part is formed by the second crystal triode and the fifth resistor connected with the collecting electrode of the second crystal triode. The thermosensitive resistor feedback sampling part samples output bias voltage; the comparison amplification part compares feedback sampling voltage with reference voltage and outputs to the first crystal triode in an amplifying way; and the first crystal triode realizes the regulation of the output bias voltage according to environment temperature. The temperature compensation circuit can effectively realize the temperature compensation of the bias voltage of the avalanche photodiode and has lower cost and power consumption and smaller volume compared with the traditional thermostatic apparatus.

Description

technical field [0001] The invention relates to a temperature compensation circuit, in particular to a circuit for temperature compensation of avalanche photodiode bias voltage. Background technique [0002] Avalanche photodiode (APD) is a highly sensitive photoelectric conversion device, which is widely used in distributed optical fiber temperature sensor, optical communication, laser ranging and other fields. When the avalanche photodiode is working normally, it needs to add a reverse bias voltage of tens to hundreds of volts to make it enter the avalanche region to obtain the best sensitivity. The optimal bias voltage is generally proportional to the ambient temperature. Higher, the higher the optimal reverse bias voltage required, and vice versa. This feature of the avalanche photodiode makes it greatly affected by the ambient temperature in specific applications. When the reverse bias operating voltage remains unchanged and the ambient temperature rises, the sensitivit...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to solve the problem that the avalanche photodiode is easily affected by the ambient temperature, and provide a low-cost circuit for temperature compensation of the bias voltage of the avalanche photodiode

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