CN-117348665-B - Low-noise high-precision voltage control current source for semiconductor laser

CN117348665BCN 117348665 BCN117348665 BCN 117348665BCN-117348665-B

Abstract

The invention discloses a low-noise high-precision voltage control current source for a semiconductor laser, which comprises a voltage control signal generating module, a PID (proportion integration differentiation) control module and an output current sampling and feedback module, wherein the voltage control signal generating module receives an upper computer instruction and generates a voltage control signal of output current, the PID control module receives and processes the voltage control signal generated by the voltage control signal generating module and feedback voltage generated by the output current sampling and feedback module to generate control voltage so as to control the output current of the output current sampling and feedback module, and the output current sampling and feedback module provides stable output current for a load and provides the current fed back to the PID control module after comparing and amplifying the voltage quantity and the voltage control signal so as to provide feedback voltage for the PID control module. The invention can realize accurate and stable current output, can adjust the output current, and can provide stable low-noise and high-precision driving current for semiconductor lasers and the like.

Inventors

FANG TAO
Zheng Manhang
CHEN WENXUAN
SUN QI
YANG CHENG
WANG LEILEI
CHEN XIANGFEI

Assignees

南京大学

Dates

Publication Date: 20260508
Application Date: 20231106

Claims (5)

1. The utility model provides a low noise high accuracy voltage control current source to semiconductor laser, includes voltage control signal generation module, PID control module, output current sampling and feedback module, voltage control signal generation module is connected with PID control module, output current sampling and feedback module electricity respectively, and PID control module and output current sampling and feedback module electricity are connected, its characterized in that: the voltage control signal generation module is used for receiving the instruction of the upper computer and generating a voltage control signal of output current; The PID control module is used for receiving and processing the voltage control signal generated by the voltage control signal generating module and the feedback voltage generated by the output current sampling and feedback module, and generating control voltage so as to control the output current of the output current sampling and feedback module; The output current sampling and feedback module is used for providing stable output current for the load, feeding back the current into the PID control module after comparing and amplifying the voltage quantity and the voltage control signal, and providing feedback voltage for the PID control module; The PID control module adopts a high-precision low-noise operational amplifier A2, wherein the in-phase end input of the operational amplifier A2 is a voltage control signal generated by the voltage control signal generating module, the reverse end input is a feedback voltage of the output current sampling and feedback module, and the PID control module is used for carrying out proportional-integral-derivative operation on the difference between the voltage control signal and the feedback voltage to output the voltage, and the voltage is provided for the output current sampling and feedback module; The PID control module comprises resistors R2, R7, R8 and R15, capacitors C1, C2 and C3 and an operational amplifier A2, wherein one end of the R2 is connected with the output end of the voltage control signal generating module, the other end of the R2 is connected with the +IN end of the operational amplifier A2, one end of the R8 is connected with the-IN end of the operational amplifier A2, the other end of the R8 is connected with one end of the R15 and an output current sampling and feedback module, the other end of the R15 is connected with one end of the C3, one end of the R7 is connected with one end of the R8, the other end of the C3 and one end of the C1, the other end of the C2 is connected with one end of the C1 and one end of the operational amplifier A2, one end of the C1 is connected with one end of the R7, the other end of the C2 is connected with the other end of the operational amplifier A2, and the output end of the operational amplifier A2 is connected with the output current sampling and feedback module. The output current sampling and feedback module comprises resistors R1, R5, R3, R4, R6, R9, R10, R11 and R12, operational amplifiers A3 and A4 and a triode Q1, wherein one end of the R1 is connected with the PID control module, the other end of the R1 is connected with a base electrode of the triode Q1, one end of the R5 is connected with VCC, the other end of the R5 is connected with a collector electrode of the triode Q1, an emitter electrode of the triode Q1 is connected with one end of the R3, one end of the R3 is connected with one end of the R4, the other end of the R3 is connected with one end of the R10 and a load, one end of the R6 is connected with ground, the other end of the R6 is connected with one end of the R4 and a +IN end of the operational amplifier A4, one end of the R10 is connected with one end of the R9 and a-IN end of the operational amplifier A4, the other end of the R9 is connected with an output end of the operational amplifier A4, the output end of the operational amplifier A4 is connected with a +IN end of the operational amplifier A3, one end of the output end of the operational amplifier A4 is connected with the output end of the operational amplifier A3, and the output end of the operational amplifier A12 is connected with the output end of the PID control module.
2. The low-noise high-precision voltage control current source for the semiconductor laser according to claim 1, wherein the voltage control signal generation module uses an MCU as a main control chip, and the MCU is in serial communication with an upper computer to receive a load output current value.
3. The low-noise high-precision voltage control current source for the semiconductor laser according to claim 2, wherein the voltage control signal generation module comprises a digital potentiometer, a high-precision reference voltage chip and an operational amplifier A1, wherein the digital potentiometer is used as a voltage dividing resistor, the high-precision reference voltage chip provides a reference voltage, and the operational amplifier A1 forms a voltage follower.
4. The low-noise high-precision voltage control current source for the semiconductor laser according to claim 3, wherein the digital potentiometer is connected with the resistor in series to divide the reference voltage, the digital potentiometer is connected with the MCU, the MCU controls the resistance of the digital potentiometer, the divided value of the divided voltage is the input voltage of the voltage follower, and the output voltage of the voltage follower is the output signal of the voltage control signal generating module.
5. The low-noise high-precision voltage control current source for a semiconductor laser according to claim 4, wherein the digital potentiometer is connected with a reference voltage chip through a resistor R13, the digital potentiometer is connected with a non-inverting input end of an operational amplifier A1 through a resistor R14, an inverting input end of the operational amplifier A1 is connected with an output end of the operational amplifier A1 through a resistor R16, and an output end of the operational amplifier A1 is respectively connected with a PID control module, an output current sampling and feedback module.

Description

Low-noise high-precision voltage control current source for semiconductor laser Technical Field The invention belongs to the technical field of photoelectric communication, and particularly relates to a low-noise high-precision voltage control current source for a semiconductor laser. Background The semiconductor laser is mainly applied to the fields of optical fiber communication, optical storage, material processing, medical research and the like, and the application fields have corresponding strict requirements on the frequency stability, spectral linewidth, power stability, strength, phase noise and the like of the laser. For an electrically excited semiconductor laser, the drive current variation, current noise and the like have obvious influence on the lasing wavelength, spectral linewidth, output power, noise and the like of the laser. In addition, for tunable laser applications, the accuracy of the current determines the wavelength tuning accuracy. Therefore, the laser driving current source is required to provide a stable, accurate and controllable driving signal for the semiconductor, reduce frequency drift, ensure the frequency stability of the laser, and have the characteristics of small noise and high accuracy. Disclosure of Invention The invention aims to solve the technical problems of the prior art, and provides a low-noise high-precision voltage control current source for a semiconductor laser, which can realize accurate and stable current output, has adjustable output current, can provide stable low-noise high-precision driving current for the semiconductor laser and the like, and can be applied to narrow-linewidth lasers, tunable lasers, laser radars and the like. In order to achieve the technical purpose, the invention adopts the following technical scheme: The low-noise high-precision voltage control current source for the semiconductor laser comprises a voltage control signal generating module, a PID control module and an output current sampling and feedback module, wherein the voltage control signal generating module is respectively and electrically connected with the PID control module and the output current sampling and feedback module, and the PID control module is electrically connected with the output current sampling and feedback module; the voltage control signal generation module is used for receiving the instruction of the upper computer and generating a voltage control signal of output current; The PID control module is used for receiving and processing the voltage control signal generated by the voltage control signal generating module and the feedback voltage generated by the output current sampling and feedback module, and generating control voltage so as to control the output current of the output current sampling and feedback module; The output current sampling and feedback module is used for providing stable output current for the load, feeding back the current into the PID control module after comparing and amplifying the voltage quantity and the voltage control signal, and providing feedback voltage for the PID control module. In order to optimize the technical scheme, the specific measures adopted further comprise: the voltage control signal generation module uses an MCU as a main control chip, and the MCU is in serial communication with the upper computer to receive the load output current value. The voltage control signal generation module comprises a digital potentiometer, a high-precision reference voltage chip and an operational amplifier A1, wherein the digital potentiometer is used as a voltage dividing resistor, the high-precision reference voltage chip provides reference voltage, and the operational amplifier A1 forms a voltage follower. The digital potentiometer is connected with the MCU in series to divide the reference voltage, the MCU controls the resistance of the digital potentiometer, the divided value of the divided voltage is the input voltage of the voltage follower, and the output voltage of the voltage follower is the output signal of the voltage control signal generation module. The digital potentiometer is connected with the reference voltage chip through a resistor R13, the digital potentiometer is connected with the non-inverting input end of the operational amplifier A1 through a resistor R14, the inverting input end of the operational amplifier A1 is connected with the output end of the operational amplifier A1 through a resistor R16, and the output end of the operational amplifier A1 is respectively connected with the PID control module and the output current sampling and feedback module. The PID control module adopts a high-precision low-noise operational amplifier A2, the non-inverting end of the operational amplifier A2 is input as a voltage control signal generated by the voltage control signal generating module, the inverting end of the operational amplifier A2 is input as a feedback voltage of the output current sampling and feedbac