Low-ripple high-stability laser driving power supply circuit, device and equipment

Abstract

The embodiment of the invention belongs to the technical field of circuit structures, and provides a low-ripple high-stability laser driving power supply circuit, device and equipment, and the circuit comprises a reference voltage module, a voltage and current conversion module, a load module, a sampling resistor, and a sampling resistor temperature control module. The output end of the reference voltage module is connected with the input end of the voltage and current module, the voltage and current conversion module is connected with the first end of the load module, the second end of the load module is connected with the first end of the sampling resistor and a feedback input port of the voltage and current conversion module, and the second end of the sampling resistor is grounded; the sampling resistor temperature control module is arranged outside the sampling resistor, the resistance temperature of the sampling resistor is adjusted to be within the preset resistance temperature value interval according to the temperature adjustment information determined by the resistance temperature value, the working current can be controlled by controlling the temperature value of the sampling resistor, and the reliability when the working current is controlled is improved.

Description

Technical Field

[0001] The present application relates to the field of circuit structure technology, and in particular to a low-ripple and high-stability laser drive power supply circuit, device and equipment. Background Art

[0002] In atomic laser cooling and trapping experiments, lasers with narrow line width and high power stability are required, because both cooling light and detection light in ultracold atomic systems must interact with the ultrafine energy levels of atoms. Ultracold atomic systems are sensitive to noise of tens to hundreds of hertz in laser power, and low-frequency noise can affect atomic lifetime and coherence time. The stability of laser power is the basis for the stable operation of cold atomic systems and the acquisition of reliable experimental results.

[0003] The relationship between laser power and injection current can usually be described by a simplified linear model. When the injection current is less than the threshold current, the output power of the laser is very small. At this stage, the relationship between the optical output power and the injection current is very weak. When the injection current reaches the threshold current, the laser begins to emit stimulated radiation, and the output optical power increases sharply, showing an obvious "inflection point". This threshold point is the starting point for the laser to actually generate laser light. Above the threshold current, the output power of the laser is linearly related to the injection current. As the current increases, the output power increases linearly. In summary, there is a threshold current between the output power of the laser and the injection current. When the injection current exceeds the threshold current, the output power is linearly related to the injection current.

[0004] A laser constant current drive power supply with a high current ripple will convert the jitter of the current ripple into the power jitter of the pump light output by the semiconductor laser pump module inside the laser, thereby affecting the output power of the laser.

[0005] At present, the constant current power supply of existing lasers can be divided into two types: switching constant current power supply and linear constant current power supply. Both solutions convert the input of the external constant voltage power supply into a constant current output to power the semiconductor laser pump module in the laser. Switching constant current power supply and linear constant current power supply are suitable for different usage scenarios.

[0006] The switching constant current power supply is suitable for scenarios with large input voltage changes and high efficiency requirements. It has good adaptability to slow changes in external input voltage (<10Hz), but because of the electronic switching elements in the components, ripple will be introduced in the output current, and ripple is inevitable. The linear constant current power supply will filter out any external input voltage fluctuations that are higher than the output voltage, and the step-down mechanism makes its output current ripple very low, but its disadvantage is that the input voltage must be higher than the output voltage, so the efficiency must be low, and it requires a larger space than the switching constant current power supply for heat dissipation. Therefore, the linear constant current power supply is suitable for application scenarios that are sensitive to power supply ripple and have no requirements for power supply efficiency.

[0007] Lasers generally use linear power supplies as driving sources. The structure of a general linear power supply (including linear constant voltage power supplies and linear constant current power supplies) consists of three parts: error amplifier, sampling resistor array, and output power tube. The error amplifier amplifies the difference between the input reference voltage and the feedback voltage fed back by the sampling resistor array, and provides a control voltage to control the output power tube.

[0008] Linear constant current power supplies generally use high-gain operational amplifiers as error amplifiers, MOS tubes as output power tubes, and the resistance of the sampling resistor is as small as possible.

[0009] The MOS tube will continuously control the output current based on the set reference voltage, and finally make the output current a fixed value. A single MOS tube as an output power tube is limited by transconductance, and the output current is generally between 100~200mA. Moreover, the MOS tube can only control the current in one direction and cannot be compatible with the output requirements of positive and negative currents. At the same time, the power loss of a linear power supply is determined by the difference between the input voltage and the output voltage multiplied by the operating current. The power consumption is sometimes low and sometimes high. Under the premise that the output voltage of the power supply control is a fixed value, most of the input power exceeding the output power is borne by the MOS tube and the sampling resistor, and there are relatively large heat dissipation requirements, which leads to reduced stability when controlling the operating current. Summary of the invention

[0010] The embodiments of the present application provide a low-ripple and high-stability laser driving power supply circuit, device and equipment, which can control the operating current by controlling the temperature value of the sampling resistor, thereby improving the stability of the low-ripple and high-stability laser driving power supply circuit during operation.

[0011] A first aspect of an embodiment of the present application provides a low ripple and high stability laser driving power supply circuit, the circuit comprising: a reference voltage module, a voltage-current conversion module, a load module, a sampling resistor, and a sampling resistor temperature control module, wherein: The output end of the reference voltage module is connected to the input end of the voltage-current module, the voltage-current conversion module is connected to the first end of the load module, the second end of the load module is connected to the first end of the sampling resistor and the feedback input port of the voltage-current conversion module, and the second end of the sampling resistor is grounded; The sampling resistor temperature control module is arranged outside the sampling resistor, and is used to determine the resistance temperature value according to the ambient temperature and property information of the sampling resistor; determine the temperature adjustment information of the sampling resistor according to the offset between the resistance temperature value and the preset resistance temperature value interval; and adjust the resistance temperature of the sampling resistor to the preset resistance temperature value interval according to the temperature adjustment information; The load module includes a semiconductor laser pump module in a laser.

[0012] In this example, the operating current can be controlled by controlling the temperature value of the sampling resistor, thereby improving the operating stability of the low ripple and high stability laser driving power supply circuit and improving the reliability of controlling the operating current.

[0013] In one possible implementation, the voltage-to-current conversion module includes: an error amplifier and a power amplifier, the in-phase terminal of the error amplifier is connected to the output terminal of the reference voltage module, the output terminal of the error amplifier is connected to the input terminal of the power amplifier, the output terminal of the power amplifier is connected to the input terminal of the load module, and the inverting input terminal of the error amplifier is connected to the second terminal of the load module.

[0014] In a possible implementation, the power amplifier includes a first operational amplifier, a first resistor, a second resistor, a first diode, a second diode, a first transistor, and a second transistor, wherein the non-inverting end of the first operational amplifier is connected to the output end of the error amplifier, the inverting end of the first operational amplifier is connected to the second end of the first resistor and the first end of the second resistor, the first end of the first resistor is grounded, the second end of the second resistor is connected to the first port of the first operational amplifier, the cathode of the first diode, and the anode of the second diode, the anode of the first diode is connected to the base of the first transistor, the collector of the first transistor is connected to the first power supply port and the second port of the first operational amplifier, the emitter of the first transistor is connected to the first end of the load module and the emitter of the second transistor, the base of the second transistor is connected to the cathode of the second diode, and the collector of the second transistor is connected to the second power supply port and the third port of the first operational amplifier.

[0015] In a possible implementation, the reference voltage module includes: a microprocessor, an input power supply and a digital-to-analog converter DAC, the output end of the input power supply is connected to the input end of the DAC, the output end of the microprocessor is connected to the control port of the DAC, and the microprocessor and the DAC are isolated by a photoelectric isolation device.

[0016] In a possible implementation, the attribute information includes the thermal resistance of the resistor shell, the assembly thermal resistance, the heat sink thermal resistance and the resistor power, and the sampling resistor temperature control module is used to determine the resistor temperature value according to the ambient temperature and attribute information of the sampling resistor, including: The sampling resistor temperature control module is used to determine the resistance temperature value by the method shown in the following formula, including: in, is the resistance temperature value, is the ambient temperature value, is the thermal resistance of the resistor case, is the assembly thermal resistance, is the heat sink thermal resistance, is the resistor power.

[0017] In a possible implementation, the microprocessor determines the power supply voltage rejection ratio of the low ripple and high stability laser driving power supply circuit by the method shown in the following formula: in, is the gain of the error amplifier, is the resistance value of the sampling resistor, Load resistance of the load module, is the power supply voltage rejection ratio of the power amplifier, is the power supply voltage rejection ratio of the error amplifier, is the gain of the power amplifier, It is the power supply voltage rejection ratio of the low ripple and high stability laser drive power supply circuit.

[0018] In a possible implementation, the microprocessor includes a single-chip microcomputer of the STM32 series.

[0019] In a possible implementation, the microprocessor determines the stability of the low ripple high stability laser driving power supply circuit by the method shown in the following formula: in, For stability, is the standard deviation of the output current of the low ripple high stability laser drive power circuit, It is the average value of the output current of the low ripple and high stability laser driving power supply circuit.

[0020] A second aspect of an embodiment of the present application provides a low-ripple and high-efficiency laser driving power supply device, which includes a circuit board and a low-ripple and high-stability laser driving power supply circuit as described in any one of the first aspects, and the low-ripple and high-stability laser driving power supply circuit is arranged on the circuit board.

[0021] The third aspect of the embodiment of the present application provides a low-ripple and high-efficiency laser driving power supply device, which includes a shell and a low-ripple and high-efficiency laser driving power supply device as described in the second aspect, and the low-ripple and high-efficiency laser driving power supply device is arranged in the shell. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 A schematic diagram of the structure of a low-ripple and high-stability laser driving power supply circuit is provided for an embodiment of the present application; Figure 2 A schematic diagram of the structure of a power amplifier is provided for an embodiment of the present application; Figure 3 A heat dissipation equivalent schematic diagram is provided for an embodiment of the present application; Figure 4 A test result diagram of a low ripple and high efficiency laser driving power supply provided in an embodiment of the present application. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0025] The terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0026] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0027] In order to better understand the low-ripple and high-stability laser driving power supply circuit provided in the embodiment of the present application, the scenario of the low-ripple and high-stability laser driving power supply circuit is first briefly introduced below. In atomic laser cooling and trapping experiments, lasers with narrow linewidth and high power stability are required, because both cooling light and detection light in the ultracold atomic system must interact with the hyperfine energy levels of atoms. Ultracold atomic systems are sensitive to noise of tens to hundreds of hertz in laser power, and low-frequency noise will affect atomic lifetime and coherence time. The stability of laser power is the basis for the stable operation of cold atom systems and the acquisition of reliable experimental results.

[0028] The relationship between laser power and injection current can usually be described by a simplified linear model. When the injection current is less than the threshold current, the output power of the laser is very small. At this stage, the relationship between the optical output power and the injection current is very weak. When the injection current reaches the threshold current, the laser begins to emit stimulated radiation, and the output optical power increases sharply, showing an obvious "inflection point". This threshold point is the starting point for the laser to actually generate laser light. Above the threshold current, the output power of the laser is linearly related to the injection current. As the current increases, the output power increases linearly. In summary, there is a threshold current between the output power of the laser and the injection current. When the injection current exceeds the threshold current, the output power is linearly related to the injection current.

[0029] A laser constant current drive power supply with a high current ripple will convert the jitter of the current ripple into the power jitter of the pump light output by the semiconductor laser pump module inside the laser, thereby affecting the output power of the laser.

[0030] At present, the linear power supply in the constant current power supply of the existing laser is used as the driving source. The structure of a general linear power supply (for example, a linear constant current power supply) includes three parts: an error amplifier, a sampling resistor array, and an output power tube. The error amplifier amplifies the difference between the input reference voltage and the feedback voltage fed back by the sampling resistor array, and provides a control voltage to control the output power tube.

[0031] Linear constant current power supplies generally use high-gain operational amplifiers as error amplifiers, MOS tubes as output power tubes, and the resistance of the sampling resistor is as small as possible. The MOS tube will continuously control the output current based on the set reference voltage, and ultimately make the output current a fixed value. A single MOS tube as an output power tube is limited by transconductance, and the output current is generally between 100 and 200 mA. Moreover, the MOS tube can only control current in one direction and cannot be compatible with the output requirements of positive and negative currents. At the same time, the power loss of a linear power supply is determined by the difference between the input voltage and the output voltage multiplied by the operating current. The power consumption is sometimes low and sometimes high. Under the premise that the output voltage controlled by the power supply is a fixed value, most of the input power exceeding the output power is borne by the MOS tube and the sampling resistor, and there are relatively large heat dissipation requirements, resulting in reduced reliability when controlling the operating current.

[0032] In order to solve the above-mentioned technical problems, the present application provides a low ripple and high stability laser driving power supply circuit, which can provide positive and negative current output values ​​for the output by means of a linear constant current power supply, and can also control the working current by controlling the temperature value of the sampling resistor, thereby improving the working stability of the low ripple and high stability laser driving power supply circuit.

[0033] See also Figure 1 , Figure 1 The present invention provides a schematic diagram of a low ripple and high stability laser driving power supply circuit. Figure 1 As shown, the circuit includes: a reference voltage module 1, a voltage-current conversion module 2, a load module 4, a sampling resistor RS, and a sampling resistor temperature control module 3, wherein: The output end of the reference voltage module 1 is connected to the input end of the voltage-current module, the voltage-current conversion module 2 is connected to the first end of the load module 4, the second end of the load module 4 is connected to the first end of the sampling resistor RS and the feedback input port of the voltage-current conversion module 2, and the second end of the sampling resistor RS is grounded; The sampling resistor temperature control module 3 is arranged outside the sampling resistor RS, and the sampling resistor temperature control module 3 is used to determine the resistance temperature value according to the ambient temperature and property information of the sampling resistor RS; determine the temperature adjustment information of the sampling resistor RS according to the offset between the resistance temperature value and the preset resistance temperature value interval; and adjust the resistance temperature of the sampling resistor RS to the preset resistance temperature value interval according to the temperature adjustment information; The load module 4 includes a semiconductor laser pump module in a laser.

[0034] Among them, the reference voltage module 1 can provide a stable input power supply through a stable reference bandgap reference voltage chip, and then output the required input reference voltage to the voltage-current conversion module 2 through the internal microprocessor. The microprocessor in the reference voltage module 1 can be a STM32 series microcontroller, and of course it can also be other microprocessors, which are not specifically limited here.

[0035] The sampling resistor temperature control module 3 can specifically control the temperature of the sampling resistor, thereby suppressing the temperature drift caused by the power loss on the sampling resistor RS. The attribute information includes the thermal resistance of the resistor shell, the assembly thermal resistance, the heat sink thermal resistance and the resistor power, and the resistance temperature value can be determined based on the collected ambient temperature of the sampling resistor RS and the attribute information of the sampling resistor RS.

[0036] The preset resistance temperature value interval may be a temperature value interval corresponding to the current laser power, and may be specifically preset by a user during use, or may be set based on experience or historical data.

[0037] The offset between the resistance temperature value and the preset resistance temperature value interval may be the smaller value of the absolute value of the difference between the resistance temperature value and the interval endpoint of the preset resistance temperature value interval. If the resistance temperature value is on the left side of the preset resistance temperature value interval, the temperature adjustment information may be a temperature value that increases the preset multiple of the offset; if the resistance temperature value is on the right side of the preset resistance temperature value interval, the temperature adjustment information may be a temperature value that decreases the preset multiple of the offset. The preset multiple may be set by an empirical value or historical data, and after the product of the preset multiple and the offset is superimposed on the resistance temperature value, the resulting resistance temperature value is within the preset resistance temperature value interval.

[0038] In this example, the operating current can be controlled by controlling the temperature value of the sampling resistor, thereby improving the operating stability of the low ripple and high stability laser driving power supply circuit.

[0039] In one possible implementation, Figure 1As shown, the voltage-to-current conversion module 2 includes: an error amplifier 20 and a power amplifier 21, the in-phase end of the error amplifier 20 is connected to the output end of the reference voltage module 1, the output end of the error amplifier 20 is connected to the input end of the power amplifier 21, the output end of the power amplifier 21 is connected to the input end of the load module 4, and the inverting input end of the error amplifier 20 is connected to the second end of the load module 4.

[0040] In one possible implementation, Figure 2 As shown, the power amplifier 21 includes a first operational amplifier 20, a first resistor R1, a second resistor R2, a first diode D1, a second diode D2, a first transistor Q1 and a second transistor Q2, wherein the in-phase end of the first operational amplifier 20 is connected to the output end Vin of the error amplifier 20, the inverting end of the first operational amplifier 20 is connected to the second end of the first resistor R1 and the first end of the second resistor R2, the first end of the first resistor R1 is grounded, the second end of the second resistor R2 is connected to the first port of the first operational amplifier 20, the first diode D1 The cathode of the first diode D1 is connected to the anode of the second diode D2, the anode of the first diode D1 is connected to the base of the first transistor Q1, the collector of the first transistor Q1 is connected to the first power supply port VCC and the second port of the first operational amplifier 20, the emitter of the first transistor Q1 is connected to the first end of the load module 4 and the emitter of the second transistor Q2, the base of the second transistor Q2 is connected to the cathode of the second diode D2, and the collector of the second transistor Q2 is connected to the second power supply port VEE and the third port of the first operational amplifier 20.

[0041] In one possible implementation, Figure 1 As shown, the reference voltage module 1 includes: a microprocessor 11, an input power supply 12 and a digital-to-analog converter DAC13, the output end of the input power supply 12 is connected to the input end of the DAC13, the output end of the microprocessor 11 is connected to the control port of the DAC13, and the microprocessor 11 and the DAC13 are isolated by a photoelectric isolation device.

[0042] According to the code setting of the microprocessor 11, it is converted into a corresponding digital control signal, which controls the DAC to generate a specific voltage Based on the voltage-current conversion module, any working current can be determined Output. Use optoelectronic isolation devices to isolate the MCU and DAC signals to prevent electrical signals from interfering with the reference voltage. Affects the accuracy.

[0043] In a possible implementation, the power amplifier 21 has a greater current output capability and a smaller input capacitance. The most important thing is that the negative feedback structure of the power amplifier 21 makes it naturally stable. After the circuit is improved, the actual current drive can reach about 580mA. Theoretically, after replacing the resistor R_S, a current output capability of no more than 8A can be obtained. And due to the role of the Class AB output stage, the circuit can have current output capabilities in both positive and negative directions.

[0044] The internal and external dual feedback loops of the error amplifier 20 and the circuit and the power amplifier 21 also improve the power supply voltage rejection ratio PSRR. PSRR is a very important parameter of the power supply, which characterizes the power supply's ability to suppress power supply ripple.

[0045] The microprocessor 11 determines the power supply voltage rejection ratio of the low ripple and high stability laser driving power supply circuit by the method shown in the following formula: in, is the gain of the error amplifier 20, is the resistance value of the sampling resistor RS, The load resistance of load module 4, is the power supply voltage rejection ratio of the power amplifier 21, is the power supply voltage rejection ratio of the error amplifier 20, is the gain of the power amplifier 21, It is the power supply voltage rejection ratio of the low ripple and high stability laser drive power supply circuit.

[0046] It can be easily seen that the gain A_ERR of the error amplifier 20 greatly improves the PSRR of the entire power supply circuit.

[0047] The efficiency of the linear constant current source is not high, and about half of the power will be accumulated in the sampling resistor RS. The sampling resistor RS is mainly affected by temperature. The ambient temperature and the heating of the sampling resistor RS itself will affect the stability of the output current. Finding the temperature at which the current output is most stable and actively controlling the sampling resistor RS at this temperature can effectively reduce the impact of temperature on the stability of the output current.

[0048] The sampling resistor temperature control module 3 can be implemented using a simple temperature control module. When the current flowing through the resistor is constant, the heating power of the resistor is also constant. The temperature of the resistor can be calculated using the thermal resistance coefficient of the resistor and the assembly.

[0049] In the calculation of thermal resistance, the heat dissipation path can be understood as follows Figure 3A simple circuit is shown in Figure 1. In this "circuit", temperature is considered as an equivalent voltage, thermal resistance is just a simple resistor, and power can be considered as current. Therefore, thermal resistance becomes a linearly additive resistor. The resistance value temperature can be calculated using the following formula: in, is the resistance temperature value, is the ambient temperature value, is the thermal resistance of the resistor case, is the assembly thermal resistance, is the heat sink thermal resistance, is the resistor power.

[0050] The sampling resistor temperature control module 3 uses the semiconductor heating plate TEC as a heat conducting plate and is equipped with a simple temperature control. The temperature variation range of the sampling resistor module can be limited to a tolerable range, thereby reducing the influence of the ambient temperature on the output current of the laser drive power supply.

[0051] In a possible implementation, the microprocessor 11 determines the stability of the low ripple and high stability laser driving power supply circuit by the method shown in the following formula: in, For stability, is the standard deviation of the output current of the low ripple high stability laser drive power circuit, is the average value of the output current of the low ripple and high stability laser drive power supply circuit. Figure 4 As shown, Figure 4 A test result diagram of the low ripple and high efficiency laser driving power supply of the present application is shown.

[0052] An embodiment of the present application provides a low-ripple and high-efficiency laser driving power supply device, which includes a circuit board and a low-ripple and high-stability laser driving power supply circuit as described in any of the aforementioned embodiments, and the low-ripple and high-stability laser driving power supply circuit is arranged on the circuit board.

[0053] An embodiment of the present application provides a low-ripple and high-efficiency laser driving power supply device, which includes a shell and a low-ripple and high-efficiency laser driving power supply device as described in the above embodiment, and the low-ripple and high-efficiency laser driving power supply device is arranged in the shell.

[0054] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the described order of actions, because according to the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

[0055] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0056] In the several embodiments provided in the present application, it should be understood that the disclosed device can be implemented in other ways. For example, the device embodiments described above are only schematic, such as the division of the units, which is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, and the indirect coupling or communication connection of the device or unit can be electrical or other forms.

[0057] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0058] A person of ordinary skill in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable memory, which can include: a flash drive, a read-only memory, a random access memory, a magnetic disk or an optical disk, etc.

[0059] The embodiments of the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A low ripple and high stability laser driving power supply circuit, characterized in that: The circuit includes: a reference voltage module, a voltage-current conversion module, a load module, a sampling resistor, and a sampling resistor temperature control module, wherein: The output end of the reference voltage module is connected to the input end of the voltage-current module, the voltage-current conversion module is connected to the first end of the load module, the second end of the load module is connected to the first end of the sampling resistor and the feedback input port of the voltage-current conversion module, and the second end of the sampling resistor is grounded; The sampling resistor temperature control module is arranged outside the sampling resistor, and is used to determine the resistance temperature value according to the ambient temperature and property information of the sampling resistor; determine the temperature adjustment information of the sampling resistor according to the offset between the resistance temperature value and the preset resistance temperature value interval; and adjust the resistance temperature of the sampling resistor to the preset resistance temperature value interval according to the temperature adjustment information; The load module includes a semiconductor laser pump module in a laser.

2. The low ripple and high stability laser driving power supply circuit according to claim 1, characterized in that: The voltage-to-current conversion module includes: an error amplifier and a power amplifier, the in-phase end of the error amplifier is connected to the output end of the reference voltage module, the output end of the error amplifier is connected to the input end of the power amplifier, the output end of the power amplifier is connected to the input end of the load module, and the inverting input end of the error amplifier is connected to the second end of the load module.

3. The low ripple and high stability laser driving power supply circuit according to claim 2, characterized in that: The power amplifier includes a first operational amplifier, a first resistor, a second resistor, a first diode, a second diode, a first transistor and a second transistor, wherein the non-inverting end of the first operational amplifier is connected to the output end of the error amplifier, the inverting end of the first operational amplifier is connected to the second end of the first resistor and the first end of the second resistor, the first end of the first resistor is grounded, the second end of the second resistor is connected to the first port of the first operational amplifier, the cathode of the first diode, and the anode of the second diode, the anode of the first diode is connected to the base of the first transistor, the collector of the first transistor is connected to the first power supply port and the second port of the first operational amplifier, the emitter of the first transistor is connected to the first end of the load module and the emitter of the second transistor, the base of the second transistor is connected to the cathode of the second diode, and the collector of the second transistor is connected to the second power supply port and the third port of the first operational amplifier.

4. The low ripple and high stability laser driving power supply circuit according to claim 2 or 3, characterized in that: The reference voltage module includes: a microprocessor, an input power supply and a digital-to-analog converter DAC, wherein the output end of the input power supply is connected to the input end of the DAC, the output end of the microprocessor is connected to the control port of the DAC, and the microprocessor and the DAC are isolated by a photoelectric isolation device.

5. The low ripple and high stability laser driving power supply circuit according to claim 4, characterized in that: The attribute information includes the thermal resistance of the resistor shell, the assembly thermal resistance, the heat sink thermal resistance and the resistor power. The sampling resistor temperature control module is used to determine the resistor temperature value according to the ambient temperature and attribute information of the sampling resistor, including: The sampling resistor temperature control module is used to determine the resistance temperature value by the method shown in the following formula, including: in, is the resistance temperature value, is the ambient temperature value, is the thermal resistance of the resistor case, is the assembly thermal resistance, is the heat sink thermal resistance, is the resistor power.

6. The low ripple and high stability laser driving power supply circuit according to claim 5, characterized in that: The microprocessor determines the power supply voltage rejection ratio of the low ripple high stability laser driving power supply circuit by the method shown in the following formula: in, is the gain of the error amplifier, is the resistance value of the sampling resistor, Load resistance of the load module, is the power supply voltage rejection ratio of the power amplifier, is the power supply voltage rejection ratio of the error amplifier, is the gain of the power amplifier, It is the power supply voltage rejection ratio of the low ripple and high stability laser drive power supply circuit.

7. The low ripple and high stability laser driving power supply circuit according to claim 6, characterized in that: The microprocessor includes a single chip microcomputer of the STM32 series.

8. The low ripple and high stability laser driving power supply circuit according to any one of claims 5 to 7, characterized in that: The microprocessor determines the stability of the low ripple high stability laser drive power supply circuit by the method shown in the following formula: in, For stability, is the standard deviation of the output current of the low ripple high stability laser drive power circuit, It is the average value of the output current of the low ripple and high stability laser driving power supply circuit.

9. A low ripple high efficiency laser driving power supply device, characterized in that: The low-ripple and high-efficiency laser driving power supply device comprises a circuit board and a low-ripple and high-stability laser driving power supply circuit as described in any one of claims 1 to 8, and the low-ripple and high-stability laser driving power supply circuit is arranged on the circuit board.

10. A low ripple high efficiency laser driving power supply device, characterized in that: The low-ripple and high-efficiency laser driving power supply device comprises a housing and the low-ripple and high-efficiency laser driving power supply device as claimed in claim 9, and the low-ripple and high-efficiency laser driving power supply device is arranged in the housing.

Images