Laser driver control system and control method

Abstract

The invention discloses a laser driver control system and a control method. The system comprises an optical sensing module, an algorithm processing module, a conversion module, a modulation module and a control module. The optical sensing module processes the optical signal generated by the laser driver to obtain an electric signal; the algorithm processing module generates a digital bias signal and a digital modulation signal; the conversion module converts the digital bias signal into a bias current signal and converts the digital modulation signal into a modulation current signal; the modulation module modulates the modulation current signal; the control module enables the laser driver to generate optical signals in a data transmission period and an expansion period. According to the laser driver control system and control method provided by the invention, detection of optical power corresponding to logic '1' or logic '0' is completed in an expansion period; completing the detection of the average light output power in a data transmission period; the bandwidth requirement on a detection related circuit is reduced, data transmission is not influenced, and the signal-to-noise ratio performance of a received signal is not influenced.

Description

Technical Field

[0001] The present invention relates to the field of laser driving, and in particular to a laser driver control system and a control method. Background Art

[0002] Figure 1 The figure shows a schematic diagram of the structure of a transmitter in an optical communication system in the prior art. The light output of the laser driver (LD) 101 is detected by the monitoring photodiode (MPD) 102, and the monitoring photodiode (MPD) 102 can generate a monitoring current proportional to the detected light intensity. The monitoring photodiode (MPD) 102 is connected to a transimpedance amplifier (TIA) 103, and the transimpedance amplifier (TIA) 103 is used to amplify the monitoring current and convert it into a monitoring voltage 104. The transimpedance amplifier (TIA) 103 is connected to an analog-to-digital converter (ADC) 105, and the analog-to-digital converter (ADC) 105 is used to convert the monitoring voltage 104 into a digital signal 106. The analog-to-digital converter (ADC) 105 is connected to a control module 107, and the control module 107 generates a bias current setting value 108 and a modulation current setting value 109 after performing algorithm processing on the digital signal 106. Then, the two current setting values ​​108 and 109 respectively pass through two digital-to-analog converters (DAC) 110 and 111 to generate bias current 112 and modulation current 113. The two digital-to-analog converters (DAC) 110 and 111 are controlled by the burst indication signal 115. The laser driver (LD) 101 generates light output under the common drive of the bias current 112 and the modulation current 113, wherein the modulation current 113 is controlled by the switch 114 to realize the switching of the logic signal "1" and the logic signal "0" of the data signal 116. Usually, the bandwidth of the circuit composed of the monitoring photodiode (MPD) 102 and the transimpedance amplifier (TIA) 103 is significantly smaller than the bandwidth of the data signal, and the limited bandwidth will make it impossible to accurately detect the peak value of the optical signal. Therefore, the bandwidth limitation of the monitoring channel has a great influence on the detection of the emission light level.

[0003] For an optical communication system, the driving current of the laser driver (LD) 101 needs to be set so that the transmission power parameters of the laser driver (LD) 101 can meet the requirements for establishing reliable communication. The two key parameters are the average optical power PA and the extinction ratio ER. The average optical power is the average value of the maximum optical power PH and the minimum optical power PL, that is:

[0004] PA=(PH+PL) / 2 (1)

[0005] The extinction ratio ER is the ratio of the maximum output optical power to the minimum output optical power, that is:

[0006] ER=10log(PH / PL) (2)

[0007] Combining formulas (1) and (2), it can be seen that as long as any two parameters among PA, PH and PL are known, ER can be calculated, and we have:

[0008] ER=10log[(2*PA-PL) / PL] (3)

[0009] ER=10log[PH / (2*PA-PH)] (4)

[0010] In the above optical communication system, the output power of the laser driver of the transmitter needs to be controlled for the following reasons: 1. To avoid damaging the laser driver, the average optical power and peak power of the laser driver must not exceed the limit; 2. To ensure reliable reception at the back end of the link, the modulation coefficient (also known as the extinction ratio ER) must meet the protocol specifications of the entire system, so different power levels corresponding to different transmission signals (for example: "1" and "0") need to be correctly set. However, a difficult problem that needs to be solved in this control system is that the characteristics of the laser driver will change significantly with temperature and time, and deviate from the ideal linear response, so the traditional method of setting "high" and "low" drive currents is not enough.

[0011] The above circuit structure for estimating the instantaneous maximum and minimum values ​​of the emitted optical power and compensating for the change in the characteristics of the laser driver based on this is limited by the bandwidth of the monitoring diode and its supporting circuit, and its effectiveness is limited.

[0012] In an optical communication system that uses burst mode to transmit data, it is more difficult to monitor the output power of the transmitter, because the average value of the optical output power may vary greatly and the instantaneous level is not stable enough, so most of the methods in the prior art do not have enough time to obtain the minimum or maximum optical output power. At the same time, the impact of temperature will be more significant, because before the data burst period, the transmitter laser driver may have been turned off for a long time, that is, it may have cooled to the ambient temperature before being activated (heated up).

[0013] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0014] The object of the present invention is to provide a laser driver control system and control method, which can reduce the bandwidth requirements for detection-related circuits, do not affect data transmission, and do not affect the signal-to-noise ratio performance of received signals.

[0015] To achieve the above object, an embodiment of the present invention provides a laser driver control system, comprising:

[0016] The optical sensor module is used to collect the optical signal generated by the laser driver and process the optical signal to obtain an electrical signal;

[0017] An algorithm processing module, used for generating a digital bias signal and a digital modulation signal based on the electrical signal and the preset signal;

[0018] A conversion module, used for converting a digital bias signal into a bias current signal transmitted to a laser driver, and converting a digital modulation signal into a modulation current signal for modulating the bias current signal;

[0019] A modulation module, configured to modulate a modulation current signal based on each logic signal; and

[0020] The control module is used to control the optical sensing module and the modulation module based on the burst state indication signal and the enable signal and to combine with the algorithm processing module to be controlled by the burst state indication signal so that the laser driver generates an optical signal in the data transmission period and the expansion period.

[0021] In one or more embodiments of the present invention, the control module includes a control circuit, and the control circuit controls the modulation module to switch each logic signal based on the burst state indication signal and the enable signal.

[0022] In one or more embodiments of the present invention, the control module includes a control circuit and a delay circuit. The control circuit controls the modulation module to switch each logic signal based on the burst state indication signal and the enable signal. The delay circuit is used to delay the enable signal and control the opening and closing of the optical sensor module through the delayed enable signal. The control circuit controls the opening and closing of the conversion module based on the burst state indication signal and the delayed enable signal.

[0023] In one or more embodiments of the present invention, the light sensing module includes a photodiode, a transimpedance amplifier and an analog-to-digital converter connected in sequence, the photodiode is used to convert the detected light signal into a current signal, the transimpedance amplifier is used to amplify the current signal and convert the amplified signal into a digital signal through the analog-to-digital converter.

[0024] In one or more embodiments of the present invention, the conversion module includes a first digital-to-analog converter and a second digital-to-analog converter, the first digital-to-analog converter is used to convert the digital bias signal into a bias current signal, and the second digital-to-analog converter is used to convert the digital modulation signal into a modulation current signal.

[0025] In one or more embodiments of the present invention, the modulation module includes a modulator and a conversion switch, the modulator is connected to the conversion switch, the conversion switch switches the logic signal based on the control of the control module and transmits it to the modulator, and the modulator modulates the modulation current signal based on the corresponding logic signal.

[0026] The present invention also discloses a laser driver control method, which is used in the laser driver control system. The control method includes:

[0027] The optical signal generated by the laser driver is collected by the optical sensing module, and the optical signal is processed to obtain an electrical signal;

[0028] Generate a digital bias signal and a digital modulation signal based on the electrical signal and the preset signal through an algorithm processing module;

[0029] The digital bias signal is converted into a bias current signal transmitted to the laser driver through a conversion module, and the digital modulation signal is converted into a modulation current signal for modulating the bias current signal;

[0030] modulating the modulation current signal based on each logic signal through a modulation module;

[0031] The control module controls the optical sensing module and the modulation module based on the burst state indication signal and the enable signal, and the algorithm processing module is controlled by the burst state indication signal so that the laser driver generates an optical signal in the data transmission period and the expansion period.

[0032] In one or more embodiments of the present invention, within the extended period, the burst status indication signal is used to control the opening and closing of the algorithm processing module, the burst status indication signal is used to control the control module to control the modulation module to switch each logic signal, the burst status indication signal and the enable signal are used to control the control module to control the delayed opening or delayed closing of the conversion module, and the control module delays the enable signal to delay the opening or closing of the optical sensor module.

[0033] In one or more embodiments of the present invention, controlling the control module through the burst status indication signal to control the modulation module to switch each logic signal includes: controlling the control circuit through the burst status indication signal to control the modulation module to switch the logic signal "1" or the logic signal "0".

[0034] In one or more embodiments of the present invention, controlling the control module through the burst status indication signal and the enable signal to control the delayed opening or delayed closing of the conversion module includes: delaying the enable signal through a delay circuit, and transmitting the burst status indication signal and the delayed enable signal to the control circuit to control the delayed opening or delayed closing of the conversion module through the control circuit.

[0035] Compared with the prior art, the laser driver control system and control method according to the embodiments of the present invention complete the detection of the optical output power corresponding to logic "1" or logic "0" in the extended period; complete the detection of the average optical output power in the data transmission period; reduce the bandwidth requirements for the detection-related circuits, do not affect data transmission, and do not affect the signal-to-noise ratio performance of the received signal.

[0036] The laser driver control system and control method of the embodiment of the present invention use conventional photodiodes to measure average optical power and extinction ratio on an extended basis and complete dual closed-loop control without full data bandwidth monitoring. The burst indication signal is inserted during signal transmission without affecting the signal channel.

[0037] The laser driver control system and control method of the embodiment of the present invention are applicable to a series of burst mode optical communication systems that comply with IEEE 802.3av, ITU-T G.984.2, ITU-T G.987.2, ITU-T G.9804.1 and similar standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a circuit schematic diagram of a laser driver control system in the prior art.

[0039] Figure 2 4 is a circuit diagram of a laser driver control system according to an embodiment of the present invention.

[0040] Figure 3 is a waveform diagram of a laser driver control system according to an embodiment of the present invention.

[0041] Figure 4 is a flow chart of a laser driver control method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0042] The specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

[0043] Unless explicitly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “comprising”, etc., will be understood to include the stated elements or components but not to exclude other elements or components.

[0044] "Coupled" or "connected" or "connected" in the specification includes both direct connection and indirect connection. Indirect connection is a connection through an intermediate medium, such as a connection through an electrically conductive medium, which may have parasitic inductance or parasitic capacitance; indirect connection may also include connection through other active or passive devices on the basis of achieving the same or similar functional purposes, such as connection through circuits or components such as switches and follower circuits. In addition, in the present invention, words such as "first" and "second" are mainly used to distinguish one technical feature from another technical feature, and do not necessarily require or imply that there is a certain actual relationship, quantity or order between these technical features.

[0045] like Figure 2 As shown, a laser driver control system includes: a light sensing module 10, an algorithm processing module 20, a conversion module 30, a modulation module 40 and a control module 50.

[0046] The optical sensor module 10 is used to collect the optical signal generated by the laser driver LD, and process the optical signal to obtain an electrical signal, which represents the output state of the monitored laser driver LD. In one embodiment, the electrical signal is a digital signal. The algorithm processing module 20 is used to generate a digital bias signal BI and a digital modulation signal MOD based on the electrical signal and a preset signal; in one embodiment, the preset signal includes a preset required average optical power PA and a required extinction ratio ER.

[0047] The conversion module 30 is used to convert the digital bias signal BI into a bias current signal Ibi transmitted to the laser driver LD, and convert the digital modulation signal MOD into a modulation current signal Imod for modulating the bias current signal Ibi. The modulation module 40 is used to modulate the modulation current signal Imod based on various logic signals to generate a modulation signal Imod'; in one embodiment, the logic signal includes a data signal, a logic "1" and a logic "0".

[0048] The control module 50 is used to control the optical sensor module 10 and the modulation module 40 based on the burst state indication signal SUD and the enable signal EN, and in combination with the algorithm processing module 20, which is controlled by the burst state indication signal SUD, so that the laser driver LD generates an optical signal within the data transmission period DTP and the extended period Ec. The extended period Ec is a period extended after the data transmission period DTP due to the delay effect of the enable signal EN.

[0049] like Figure 2As shown, the optical sensing module 10 includes a photodiode MPD, a transimpedance amplifier TIA, and an analog-to-digital converter ADC connected in sequence. The cathode of the photodiode MPD is connected to the power supply voltage, and the anode of the photodiode MPD is connected to the input end of the transimpedance amplifier TIA. The light output of the laser driver LD is detected by the photodiode MPD, and the photodiode MPD converts the detected light signal into a current signal proportional to the intensity of the detected light signal. The output end of the transimpedance amplifier TIA is connected to the input end of the analog-to-digital converter ADC, and an adjustable resistor is connected in parallel to the input and output ends of the transimpedance amplifier TIA. The output end of the analog-to-digital converter ADC is connected to the algorithm processing module 20. The transimpedance amplifier TIA is used to amplify the current signal and convert it into an analog voltage signal, and then the amplified analog voltage signal is converted into a digital signal through the analog-to-digital converter ADC.

[0050] In the data transmission period, the optical sensor module 10 outputs a digital signal proportional to the average optical power of the laser driver LD; in the extended period, the optical sensor module 10 outputs a digital signal proportional to the logic "1" or logic "0" output by the laser driver LD.

[0051] The algorithm processing module 20 performs a comparison algorithm on the digital signal and the preset required average optical power PA and required extinction ratio ER, and generates a digital bias signal BI and a digital modulation signal MOD.

[0052] like Figure 2 As shown, the conversion module 30 includes a first digital-to-analog converter DAC1 and a second digital-to-analog converter DAC2. The first digital-to-analog converter DAC1 is used to convert the digital bias signal BI into a bias current signal Ibi, and the second digital-to-analog converter DAC2 is used to convert the digital modulation signal MOD into a modulation current signal Imod.

[0053] The modulation module 40 includes a modulator 41 and a conversion switch 42. The modulator 41 is connected to the conversion switch 42. The conversion switch 42 switches the logic signal based on the control of the control module 50 and transmits it to the modulator 41. The modulator 41 modulates the modulation current signal Imod based on the corresponding logic signal to generate a modulation signal Imod'. In one embodiment, the data signal, logic "1" or logic "0" is selected by the conversion switch 42 to input the modulator 41 to modulate the modulation current signal Imod.

[0054] In one embodiment, the light signal emitted by the laser driver LD under the drive of the bias current signal Ibi and the modulation current signal Imod is detected by the photodiode MPD and generates a photocurrent signal that can reflect the size of the emitted light power. The photocurrent signal is amplified by the transimpedance amplifier TIA and converted into a voltage signal. Then, the voltage signal is converted into a digital signal by the analog-to-digital converter ADC and enters the algorithm processing module 32.

[0055] like Figure 2 As shown, the control module 50 includes a control circuit 51 and a delay circuit 52. The control circuit 51 controls the modulation module 40 to switch each logic signal based on the enable signal EN and the burst state indication signal SUD. The delay circuit 52 is used to delay the enable signal EN and control the opening and closing of the light sensing module 10 through the delayed enable signal EN. The control circuit 51 controls the opening and closing of the conversion module 30 based on the burst state indication signal SUD and the delayed enable signal EN. In other embodiments, the delay circuit 52 may not be provided, and the enable signal EN may be delayed by the control circuit 51.

[0056] In a conventional burst mode system, at the end of the data transmission cycle, the bias current signal Ibi and the modulation current signal Imod will also be turned off synchronously. Figure 3 As shown, during the delay time generated by the delay circuit 52, the enable signal EN generates control signals D1 and D2 based on the delay of the enable signal EN and the burst state indication signal SUD by controlling the control circuit 51 to control the first digital-to-analog converter DAC1 and the second digital-to-analog converter DAC2 to keep the bias current signal Ibi and the modulation current signal Imod in the enabled state.

[0057] like Figure 3 Combination Figure 2 As shown, the logic value of the burst state indication signal SUD can be set to "1" or "0". When the logic value of the burst state indication signal SUD is "1", in the extended period Ec after the data transmission period DTP, the control circuit 51 controls the conversion switch 42 to select the logic "1" input based on the burst state indication signal SUD, so that the modulator 41 keeps the output modulation signal Imod' at the logic "1" level in the extended period Ec, and the holding time needs to be less than the laser driver LD closing time t specified in the protocol, and at the same time greater than the time required for the analog-to-digital converter ADC of the optical sensor module 10 to reach a stable output digital signal.

[0058] Similarly, when the logic value of the burst state indication signal SUD is "0", in the extended period Ec after the data transmission period DTP, the control circuit 51 controls the conversion switch 42 to select the logic "0" input based on the burst state indication signal SUD, so that the modulator 41 keeps the output modulation signal Imod' at the logic "0" level in the extended period Ec, and the holding time requirement is the same as that of the logic "1", that is, the conversion switch 42 can maintain the corresponding modulation current signal Imod at the same logic "1" or logic "0" according to the logic "1" or logic "0" of the burst state indication signal SUD in the extended period Ec after the data transmission period DTP. In the extended period Ec, the analog voltage signal output by the transimpedance amplifier TIA is converted into a digital signal by the analog-to-digital converter ADC and enters the algorithm processing module 20. In the extended period Ec, the digital signal processing can be used to obtain the maximum optical power PH corresponding to the transmission logic "1" or the minimum optical power PL corresponding to the logic "0".

[0059] like Figure 3 As shown, at the end of the extended period Ec, the switching switch 42 selects logic "0" to quickly reduce the light output, and at the same time the control circuit 51 outputs control signals D1 and D2 to control the shutdown of the first digital-to-analog converter DAC1 and the second digital-to-analog converter DAC2 to shut down the output current, so that the laser driver LD is completely shut down within the time t specified by the relevant protocol.

[0060] After obtaining the average optical power in the data transmission period DTP and the optical power corresponding to the logic "1" or logic "0" in the extended period Ec, the algorithm processing module 32 can obtain the measured average optical power and extinction ratio through calculation, and after comparing with the required average optical power PA and the required extinction ratio ER, a new digital bias signal BI and a digital modulation signal MOD can be obtained through calculation, thereby reducing the difference between the measured average optical power and extinction ratio and the required average optical power PA and the required extinction ratio ER until the measured value is equal to the required value, thereby realizing closed-loop control. This process may require multiple iterations of the logic "1" or logic "0" of the extended period Ec.

[0061] like Figure 4 As shown, an embodiment further discloses a laser driver LD control method, which is used for the above-mentioned laser driver LD control system, and the control method includes:

[0062] The optical signal generated by the laser driver LD is collected by the optical sensing module 10, and the optical signal is processed to obtain an electrical signal representing the collected output state of the laser driver LD.

[0063] The algorithm processing module 20 generates a digital bias signal BI and a digital modulation signal MOD based on the electrical signal and the preset signal.

[0064] The conversion module 30 converts the digital bias signal BI into a bias current signal Ibi transmitted to the laser driver LD, and converts the digital modulation signal MOD into a modulation current signal Imod for modulating the bias current signal Ibi. The optical output of the laser driver LD is controlled by the bias current signal Ibi and the modulation current signal Imod.

[0065] The modulation current signal Imod is modulated by the modulation module 40 based on various logic signals.

[0066] The optical sensing module 10 and the modulation module 40 are controlled by the control module 50 based on the burst state indication signal SUD and the enable signal EN, and combined with the algorithm processing module 20 controlled by the burst state indication signal SUD so that the laser driver LD generates an optical signal within the data transmission period DTP and the extension period Ec. The extension period Ec is a period extended after the data transmission period DTP due to the delay effect of the enable signal EN.

[0067] In one embodiment, according to the extended period Ec caused by the delay of the enable signal EN, the bias current signal Ibi and the modulation current signal Imod are input into the laser driver LD under the control of the burst state indication signal SUD and the enable signal EN.

[0068] In the data transmission period DTP, the laser driver LD outputs an electrical output proportional to the average optical power of the laser driver LD; in the extended period Ec, the laser driver LD outputs an electrical output proportional to the logic "1" or logic "0" output by the laser driver LD.

[0069] In the extended period Ec, the burst state indication signal SUD controls the on and off of the algorithm processing module 20. The algorithm processing module 20 is turned on and off under the control of the burst state indication signal SUD, and calculates the average optical power and the extinction ratio according to the digital signal output by the analog-to-digital converter ADC, and after comparing with the preset required average optical power PA and the required extinction ratio ER, generates a digital bias signal BI and a digital modulation signal MOD for controlling the optical output of the laser driver LD.

[0070] In the extended period Ec, the control module 50 is controlled by the burst state indication signal SUD to control the modulation module 40 to switch each logic signal. Specifically, the control circuit 51 is controlled by the logic value "1" or "0" of the burst state indication signal SUD to control the modulation module 40 to switch the logic "1" or the logic "0". When the burst indication signal SUD changes, according to the logic value "1" or the logic value "0" of the burst indication signal SUD, the control circuit 51 controls the conversion switch 42 to maintain the corresponding modulation signal at the same logic "1" or logic "0".

[0071] In the extended period Ec, the control module 50 is controlled by the burst state indication signal SUD and the enable signal EN to control the conversion module 30 to be delayed on or off, and the enable signal EN is delayed by the control module 50 to delay on or off the light sensing module 10. Specifically, the enable signal EN is delayed by the delay circuit 52, and the burst state indication signal SUD and the delayed enable signal EN are transmitted to the control circuit 51 to control the conversion module 30 to be delayed on or off by the control circuit 51.

[0072] Under the control of the burst indication signal SUD and the delayed enable signal EN, the algorithm processing module 20, the analog-to-digital converter ADC, the first digital-to-analog converter DAC1 and the second digital-to-analog converter DAC2 are kept turned on during the extended period Ec, so as to maintain the bias current signal Ibi and the modulation current signal Imod in a certain delay time, and control the input of the conversion switch 42. In one embodiment, the delay time needs to be less than the laser off time specified by the optical communication protocol, and at the same time greater than the time required to generate a digital signal to achieve a stable output.

[0073] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and illustration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings, and the present invention can be implemented in other forms, structures, arrangements, proportions, and with other components, materials and parts. The purpose of selecting and describing exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can implement and utilize various different exemplary embodiments of the present invention and various different selections and changes without departing from the scope and spirit of the present invention. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A laser driver control system, characterized in that: include: The optical sensor module is used to collect the optical signal generated by the laser driver and process the optical signal to obtain an electrical signal; An algorithm processing module, used for generating a digital bias signal and a digital modulation signal based on the electrical signal and the preset signal; A conversion module, used for converting a digital bias signal into a bias current signal transmitted to a laser driver, and converting a digital modulation signal into a modulation current signal for modulating the bias current signal; A modulation module, used for modulating a modulation current signal based on each logic signal; as well as The control module is used to control the optical sensing module and the modulation module based on the burst state indication signal and the enable signal and to combine with the algorithm processing module to be controlled by the burst state indication signal so that the laser driver generates an optical signal in the data transmission period and the expansion period.

2. The laser driver control system according to claim 1, characterized in that: The control module includes a control circuit, and the control circuit controls the modulation module to switch various logic signals based on a burst state indication signal and an enable signal.

3. The laser driver control system according to claim 1, characterized in that: The control module includes a control circuit and a delay circuit. The control circuit controls the modulation module to switch each logic signal based on the burst state indication signal and the enable signal. The delay circuit is used to delay the enable signal and control the opening and closing of the light sensing module through the delayed enable signal. The control circuit controls the opening and closing of the conversion module based on the burst state indication signal and the delayed enable signal.

4. The laser driver control system according to claim 1, characterized in that: The optical sensing module includes a photodiode, a transimpedance amplifier and an analog-to-digital converter connected in sequence, wherein the photodiode is used to convert the detected optical signal into a current signal, and the transimpedance amplifier is used to amplify the current signal and convert the amplified signal into a digital signal through the analog-to-digital converter.

5. The laser driver control system according to claim 1, characterized in that: The conversion module includes a first digital-to-analog converter and a second digital-to-analog converter, the first digital-to-analog converter is used to convert a digital bias signal into a bias current signal, and the second digital-to-analog converter is used to convert a digital modulation signal into a modulation current signal.

6. The laser driver control system according to claim 1, characterized in that: The modulation module includes a modulator and a conversion switch. The modulator is connected to the conversion switch. The conversion switch switches the logic signal based on the control of the control module and transmits it to the modulator. The modulator modulates the modulation current signal based on the corresponding logic signal.

7. A laser driver control method, characterized in that: For use in a laser driver control system according to any one of claims 1 to 6, the control method comprises: The optical signal generated by the laser driver is collected by the optical sensing module, and the optical signal is processed to obtain an electrical signal; Generate a digital bias signal and a digital modulation signal based on the electrical signal and the preset signal through an algorithm processing module; The digital bias signal is converted into a bias current signal transmitted to the laser driver through a conversion module, and the digital modulation signal is converted into a modulation current signal for modulating the bias current signal; modulating the modulation current signal based on each logic signal through a modulation module; The control module controls the optical sensing module and the modulation module based on the burst state indication signal and the enable signal, and the algorithm processing module is controlled by the burst state indication signal so that the laser driver generates an optical signal in the data transmission period and the expansion period.

8. The laser driver control method according to claim 7, characterized in that: During the extended period, the burst status indication signal is used to control the opening and closing of the algorithm processing module, the burst status indication signal is used to control the control module to control the modulation module to switch each logic signal, the burst status indication signal and the enable signal are used to control the control module to control the delayed opening or delayed closing of the conversion module, and the control module delays the enable signal to delay the opening or closing of the optical sensor module.

9. The laser driver control method according to claim 8, characterized in that: The controlling the control module through the burst state indication signal to control the modulation module to switch each logic signal includes: controlling the control circuit through the burst state indication signal to control the modulation module to switch the logic signal "1" or the logic signal "0".

10. The laser driver control method according to claim 8, characterized in that: The method of controlling the control module through the burst state indication signal and the enable signal to control the delayed opening or delayed closing of the conversion module includes: delaying the enable signal through a delay circuit, and transmitting the burst state indication signal and the delayed enable signal to the control circuit to control the delayed opening or delayed closing of the conversion module through the control circuit.

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