A current regulation circuit and a laser module

Abstract

This application provides a current regulation circuit and a laser module, applied in the field of laser technology. The circuit includes a main control module, a sampling resistor, and a constant current control circuit. The main control module includes a first power supply terminal, a sampling terminal, and a constant current control terminal. The first power supply terminal is connected to the operating power supply. The sampling resistor is connected between the operating power supply and the sampling terminal. The sampling terminal of the main control module is used to acquire the sampling voltage of the sampling resistor. The controlled terminal of the constant current control circuit is connected to the constant current control terminal of the main control module. The main control module is used to obtain a target driving signal based on the sampling voltage and a preset voltage threshold, and input the target driving signal into the controlled terminal of the constant current control circuit. One end of the laser is connected to the output terminal of the constant current control circuit, and the other end is connected to the operating power supply. The constant current control circuit adjusts the operating current of the laser within a preset current range corresponding to the sampling resistor according to the target driving signal. The current supply is stable, meeting the operating requirements of the laser.

Description

Technical Field

[0001] This application relates to the field of power electronics technology, specifically to a current regulation circuit and a laser module. Background Technology

[0002] In current laser applications, precise current regulation plays a crucial role in ensuring the safe and efficient operation of the laser. The current supply not only affects the stability of the laser's output power but also the threshold drift caused by temperature changes. Therefore, a stable current supply is key to ensuring the long-term stable and reliable operation of the laser at its set operating point. In view of this, how to regulate the current input to the laser and ensure the stability of the current supply has become one of the technical problems that urgently need to be solved by those skilled in the art. Utility Model Content

[0003] In view of this, this application aims to provide a current regulation circuit and a laser module to provide a stable current for the laser and meet the laser's operating requirements.

[0004] In a first aspect, this application provides a current regulating circuit for regulating the operating current of a laser, the current regulating circuit comprising:

[0005] The main control module includes a first power supply terminal, a sampling terminal, and a constant current control terminal, wherein the first power supply terminal is connected to the working power supply.

[0006] A sampling resistor is connected between the operating power supply and the sampling terminal of the main control module. The sampling terminal of the main control module is used to acquire the sampling voltage of the sampling resistor.

[0007] A constant current control circuit includes a controlled terminal and an output terminal. The controlled terminal of the constant current control circuit is connected to the constant current control terminal of the main control module. The main control module is used to obtain a target driving signal based on the sampled voltage and a preset voltage threshold, and input the target driving signal into the controlled terminal of the constant current control circuit.

[0008] One end of the laser is connected to the output of the constant current control circuit, and the other end is connected to the power supply. The constant current control circuit is used to adjust the operating current of the laser within a preset current range corresponding to the sampling resistor according to the target driving signal.

[0009] In one optional implementation, the main control module further includes a luminance control terminal, which is used to receive a pulse drive signal, and the main control module adjusts the target drive signal according to the pulse drive signal.

[0010] In one optional embodiment, the current regulation circuit provided in the first aspect of this application further includes: a drive circuit, wherein,

[0011] The output terminal of the driving circuit is connected to the brightness control terminal and the reference power supply respectively. The reference power supply is used to output the base voltage.

[0012] The driving circuit is used to output a target pulse control signal, which is superimposed on the base voltage to obtain the pulse driving signal.

[0013] In one optional implementation, the driving circuit includes a comparator and a reference circuit, wherein,

[0014] The positive input terminal of the comparator is used to receive the initial pulse control signal, and the inverting input terminal of the comparator is connected to the output terminal of the reference circuit, which is used to output the threshold voltage.

[0015] The output of the comparator is connected to the brightness control terminal and the reference power supply, respectively.

[0016] The comparator is used to output the target pulse control signal based on the initial pulse control signal and the threshold voltage.

[0017] In one optional implementation, the main control module further has a second power supply terminal, which is used to output a preset driving voltage;

[0018] The reference circuit includes a first resistor and a first diode, wherein,

[0019] One end of the first resistor is connected to the second power supply terminal, and the other end of the first resistor is connected to the anode of the first diode;

[0020] The cathode of the first diode is grounded;

[0021] The connection point between the first resistor and the first diode is connected to the inverting input terminal of the comparator.

[0022] In one optional embodiment, the driving circuit further includes a voltage divider circuit, the voltage divider circuit including a second resistor and a third resistor, wherein,

[0023] One end of the second resistor is used to receive the initial pulse control signal, and the other end of the second resistor is connected to one end of the third resistor;

[0024] The other end of the third resistor is grounded;

[0025] The connection point between the second resistor and the third resistor is connected to the positive input terminal of the comparator.

[0026] In one optional embodiment, the constant current control circuit includes: an inductor, a switching circuit, and a unidirectional conduction circuit, wherein,

[0027] One end of the inductor serves as the output terminal of the constant current control circuit, the other end of the inductor is connected to the first terminal of the switching circuit, and the second terminal of the switching circuit is grounded.

[0028] The control terminal of the switching circuit serves as the controlled terminal of the constant current control circuit.

[0029] The connection point between the inductor and the switching circuit is connected to one end of the unidirectional conduction circuit, and the other end of the unidirectional conduction circuit is connected to the first power supply terminal of the main control module.

[0030] The conduction direction of the unidirectional conduction circuit is the same as the voltage drop direction of the sampling resistor.

[0031] In one optional embodiment, the switching circuit includes: a controllable switch, a fourth resistor, and a fifth resistor, wherein,

[0032] One end of the fourth resistor serves as the control terminal of the switching circuit, and the other end of the fourth resistor is connected to one end of the fifth resistor;

[0033] The other end of the fifth resistor is grounded;

[0034] The connection point of the fourth resistor and the fifth resistor is connected to the control terminal of the controllable switch;

[0035] The first end of the controllable switch serves as the first end of the switching circuit, and the second end of the controllable switch serves as the second end of the switching circuit.

[0036] In one optional implementation, the main control module further includes a luminance control terminal and a second power supply terminal, wherein,

[0037] The second power supply terminal is used to output a preset drive voltage;

[0038] When the second power supply terminal is connected to the brightness control terminal, the brightness adjustment function of the main control module is disabled.

[0039] Secondly, this application provides a laser module, including a laser and a current regulation circuit as described in any embodiment of the first aspect of this application, wherein the current regulation circuit is electrically connected to the laser and is used to regulate the operating current of the laser.

[0040] Based on the above, the current regulation circuit provided in this application is used to regulate the operating current of a laser. This circuit includes a main control module, a sampling resistor, and a constant current control circuit. The main control module includes a first power supply terminal, a sampling terminal, and a constant current control terminal. The first power supply terminal is connected to the operating power supply. The sampling resistor is connected between the operating power supply and the sampling terminal. The sampling terminal of the main control module is used to acquire the sampling voltage of the sampling resistor. The controlled terminal of the constant current control circuit is connected to the constant current control terminal of the main control module. The main control module is used to obtain a target driving signal based on the sampling voltage and a preset voltage threshold, and input the target driving signal to the controlled terminal of the constant current control circuit. One end of the laser is connected to the output terminal of the constant current control circuit, and the other end is connected to the operating power supply. The constant current control circuit is used to adjust the operating current of the laser within a preset current range corresponding to the sampling resistor based on the target driving signal. The current regulation circuit provided in this application can adjust the operating current of the laser within a preset current range, ensuring a stable current supply and meeting the operating requirements of the laser. Furthermore, the preset current range corresponds to the sampling resistor. In practical applications, the preset current range can be adjusted by adjusting the sampling resistor, thereby meeting the power supply requirements of different lasers and making the application more flexible. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of this utility model or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a structural block diagram of a current regulation circuit provided in an embodiment of this application.

[0043] Figure 2 This is a circuit topology diagram of a current regulation circuit provided in an embodiment of this application.

[0044] Figure 3 This is a block diagram of another current regulation circuit provided in the embodiments of this application.

[0045] Figure 4 This is a structural block diagram of another current regulation circuit provided in the embodiments of this application.

[0046] Figure 5 This is a circuit topology diagram of another current regulation circuit provided in the embodiments of this application.

[0047] Figure 6 This is a circuit topology diagram of another current regulation circuit provided in the embodiments of this application.

[0048] Figure 7This is a structural block diagram of a main control module provided in an embodiment of this application. Detailed Implementation

[0049] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0050] As mentioned earlier, a stable current supply is crucial for ensuring the long-term stable and reliable operation of a laser at a set operating point. To address the problem of providing a stable current to a laser in related technologies, this application provides a current regulation circuit, which includes a main control module, a sampling resistor, and a constant current control circuit. The sampling resistor samples the operating current and converts it into a sampling voltage. The main control module controls the constant current control circuit based on the sampling voltage of the sampling resistor to limit the operating current supplied to the laser within a preset current range. The stable current supply can meet the operating requirements of the laser.

[0051] Based on the above, see Figure 1 The current regulation circuit provided in this application embodiment includes a main control module 10, a constant current control circuit 20, and a sampling circuit Rs.

[0052] Specifically, the main control module 10 includes a first power supply terminal VIN, a sampling terminal CS, and a constant current control terminal DRV. The first power supply terminal VIN of the main control module 10 is connected to the operating power supply P1, which outputs electrical energy to drive the laser. In a preferred embodiment, the first power supply terminal VIN is also connected to input-side filter capacitors C1, C2, and C3. These input-side filter capacitors can filter out high-frequency noise in the power supply path of the operating power supply P1, providing a stable DC power supply for the entire subsequent circuit and contributing to a stable current output. It should be noted that... Figure 1 The input-side filter capacitor settings shown are for illustrative purposes only. In practical applications, the number of input-side filter capacitors can be reasonably set according to the performance parameters of the power supply P1 and the application scenario of the current regulation circuit. This application does not impose any specific limitations on this.

[0053] The constant current control circuit 20 includes a controlled terminal CTRL and an output terminal O1, combined with Figure 1 As shown, the controlled terminal CTRL is connected to the constant current control terminal DRV of the main control module 10.

[0054] One end of the sampling resistor Rs is connected to the working power supply P1, and the other end is connected to the sampling terminal CS of the main control module 10. It can be understood that when current flows through the sampling resistor Rs, a corresponding sampling voltage will be generated at its two ends. The sampling terminal of the main control module 10 collects the sampling voltage of the sampling resistor Rs.

[0055] In a preferred embodiment, the load port of the current regulation circuit is also connected to output-side filter capacitors C4, C5, and C6. Similar to the aforementioned input-side filter capacitors, they are mainly used to filter out high-frequency noise on the power supply path and provide a clean and stable DC power supply for the laser. In practical applications, the output-side filter capacitors can be set according to the specific application scenario of the current regulation circuit (mainly considering the severity of electromagnetic interference) and the quality requirements of the laser for DC power. This will not be described in detail here.

[0056] As mentioned above, the main control module 10 collects the sampling voltage across the sampling resistor Rs, determines the target driving signal based on the relationship between the sampling voltage and the preset voltage threshold, and outputs the target driving signal to the constant current control circuit 20 through the constant current control terminal DRV.

[0057] One end of the laser is connected to the output terminal O1 of the constant current control circuit, and the other end of the laser is connected to the working power supply P1. The constant current control circuit 20 is used to adjust the working current of the laser within the preset voltage range corresponding to the sampling resistor Rs according to the obtained target driving signal.

[0058] It is understandable that the sampling resistor Rs is connected in series in the laser's power supply circuit. The operating current output to the laser must pass through the sampling resistor Rs. Given a fixed resistance value for Rs, the sampling voltage across Rs is directly proportional to the magnitude of the operating current. Therefore, the sampling voltage fed back by Rs can directly reflect the magnitude of the operating current supplied to the laser. Correspondingly, given a fixed sampling voltage range (i.e., a preset voltage threshold), the resistance value of Rs corresponds to the range of the operating current output by the current regulation circuit. Therefore, a correspondence can be established between the sampling resistor Rs and the preset current range. In other words, for a given preset voltage threshold, different sampling resistors Rs correspond to different operating current ranges. Therefore, in practical applications, the specific value of the sampling resistor Rs needs to be determined based on the specific value of the preset voltage threshold and the expected operating current range.

[0059] In summary, the current regulation circuit provided in this embodiment outputs a target driving signal based on the relationship between the sampled voltage and the preset voltage threshold, thereby controlling the constant current control circuit to limit the operating current provided by the laser within the preset current range, ensuring a stable current supply and meeting the operating requirements of the laser.

[0060] In one possible embodiment, the preset current range corresponds to the sampling resistor. In practical applications, the preset current range can be adjusted by adjusting the sampling resistor, thereby meeting the power supply requirements of different lasers and making the application more flexible.

[0061] As a preferred embodiment, this application provides another current regulation circuit, see [link to previous document]. Figure 2 As shown, the constant current control circuit 20 provided in this embodiment includes an inductor L1, a switching circuit 210, and a unidirectional conduction circuit 220.

[0062] The switching circuit 210 includes a controllable switch Q1, a fourth resistor R4, and a fifth resistor R5, combined with... Figure 2 As shown, one end of the fourth resistor R4 serves as the control terminal of the switching circuit 210, that is, as the controlled terminal CTRL of the constant current control circuit 20, and is connected to the constant current control terminal DRV of the main control circuit 10. The other end of the fourth resistor R4 is connected to one end of the fifth resistor R5, and the other end of the fifth resistor R5 is grounded. As an optional implementation, the switching circuit 210 also includes a second diode D2. The anode of the second diode D2 is connected to the connection point of the fourth resistor R4 and the fifth resistor R5, and the cathode of the second diode D2 is connected to the other end of the fourth resistor R4. The fourth resistor R4, the fifth resistor R5, and the second diode D2 are mainly used to improve the turn-on speed and turn-off speed of the controllable switch Q1. Specifically, the fourth resistor R4 is used to improve the turn-on speed of the controllable switch Q1, and the fifth resistor R5 and the second diode D2 are used to improve the turn-off speed of the controllable switch Q1.

[0063] The control terminal of the controllable switch Q1 is connected to the junction of the fourth resistor R4 and the fifth resistor R5. The first terminal of the controllable switch Q1 serves as the first terminal of the switching circuit 210, and the second terminal of the controllable switch Q1 serves as the second terminal of the switching circuit 210. It should be noted that in... Figure 2 In the embodiment shown, the controllable switch Q1 is implemented using a MOS (metal-oxide semiconductor) transistor. In practical applications, other controllable switching transistors, such as IGBT (Insulated-Gate Bipolar Transistor), can also be selected. These will not be listed here, and they are also within the scope of protection of this application as long as they do not exceed the core concept of this application.

[0064] One end of inductor L1 serves as the output terminal of constant current control circuit 20, and the other end of inductor L1 is connected to the first terminal of switching circuit 210, while the second terminal of switching circuit 210 is grounded. Furthermore, the connection point between inductor L1 and switching circuit 210 is connected to one end of unidirectional conduction circuit 220. The other end of unidirectional conduction circuit 220 serves as the freewheeling terminal of constant current control circuit 20 and is connected to the first power supply terminal VIN of main control module 10. The conduction direction of unidirectional conduction circuit 220 is the same as the voltage drop direction of sampling resistor Rs.

[0065] It should be noted that, in Figure 2 In the illustrated embodiment, the unidirectional conduction circuit 220 is implemented based on a third diode D3. The anode of the third diode D3 is connected to the connection point of the switching circuit 210 and the inductor L1, and the cathode of the third diode D3 is connected to the first power supply terminal VIN of the main control module 10. Of course, in practical applications, the unidirectional conduction circuit 220 can also be implemented in other ways. Any implementation method that can meet the unidirectional conduction requirement is optional and falls within the scope of protection of this application.

[0066] As an optional implementation, the constant current control circuit 20 further includes a filter circuit 230, wherein the filter circuit 230 includes a sixth resistor R6 and a filter capacitor C7, combined with... Figure 2 As shown, one end of the sixth resistor R6 is connected to the first terminal of the switching circuit 210, and the other end of the sixth resistor R6 is connected to the other end of the filter capacitor C7, which is grounded. By setting up the filter circuit 230, the current spikes and voltage spikes that occur during the frequent switching of the controllable switch Q1 can be absorbed, thereby providing a more stable DC power supply to the laser.

[0067] Figure 2 The connection relationships and functions of other circuit components in the illustrated embodiments can be referred to the relevant content of the foregoing embodiments, and will not be repeated here.

[0068] The following is combined with Figure 2 The circuit topology provided in the illustrated embodiment details the process of adjusting the laser's operating current using a current regulation circuit.

[0069] As mentioned earlier, the sampling resistor Rs converts the laser's operating current into a sampling voltage, which is fed back to the main control module 10. The main control module 10 compares the obtained sampling voltage with a preset voltage threshold and adjusts the output target drive signal based on the comparison result. Based on this, see [link to relevant documentation]. Figure 2 The circuit topology shown is based on Figure 2As shown in the circuit topology, the operating current of the laser is equal to the current of inductor L1 and the current of sampling resistor Rs (the three are in series). Based on this, after the circuit is powered on, since the current of inductor L1 cannot change abruptly, the current in sampling resistor Rs is also zero, and the sampling voltage is also zero. After the main control module 10 obtains the sampling voltage, it compares the obtained sampling voltage with the first voltage threshold (the preset voltage threshold includes the first voltage threshold and the second voltage threshold, and the first voltage threshold is greater than the second voltage threshold). The sampling voltage is less than the first voltage threshold, so the main control module 10 controls the switching circuit 210 to turn on. Thus, the operating power supply P1 is grounded through the sampling resistor Rs, the laser, inductor L1 and the switching circuit 210, forming a closed circuit. Inductor L1 stores electrical energy, and the current of inductor L1 gradually increases, and the operating current of the laser also gradually increases.

[0070] As the laser's operating current gradually increases, the sampling voltage fed back to the main control module 10 by the sampling resistor Rs also gradually increases. When the sampling voltage exceeds the first voltage threshold, the main control module 10 drives the switching circuit 210 to turn off. At this time, due to the continuity of the inductor current, the inductor current is transmitted through the laser, the unidirectional conduction circuit 220, and the sampling resistor Rs, and the inductor L1 releases the electrical energy it stores. As the inductor current gradually decreases, the sampling voltage fed back by the sampling resistor Rs also gradually decreases. When the sampling voltage is less than the first voltage threshold but greater than (or equal to) the second voltage threshold, the main control module 10 will maintain the off state of the switching circuit 210.

[0071] In one possible embodiment, when the sampling voltage fed back by the sampling resistor Rs is less than the second voltage threshold, the main control module 10 drives the switching circuit 210 to turn on, and the working power supply P1 is grounded through the sampling resistor Rs, the laser, the inductor L1 and the switching circuit 210, forming a closed path again and entering the next cycle.

[0072] Based on the above, it can be seen that the main control module 10 can limit the operating current of the laser to a preset current range by comparing the magnitude of the sampled voltage with the preset voltage threshold through the constant current control circuit.

[0073] It should be noted that the current regulation circuits provided in the above embodiments can limit the laser's operating current to a preset current range by configuring a sampling resistor and a preset voltage threshold. In other words, the maximum and minimum values ​​of the laser's operating current can be set, and the operating current can be any current value within the preset current range. However, in practical applications of lasers, it may be required that the operating current be a constant value, that is, the current regulation circuit should be able to adjust the laser's operating current within the preset current range corresponding to that constant value.

[0074] To meet the above requirements, this application provides another current regulation circuit, see [link to relevant documentation]. Figure 3 As shown, in the current regulation circuit provided in this embodiment, the main control module 10 is also provided with a brightness control terminal DIM and a second power supply terminal VCC.

[0075] The brightness control terminal DIM receives pulse drive signals. The main control module 10 adjusts the output target drive signal according to the pulse drive signal, thereby limiting the laser's operating current within a preset current range. The specific process by which the main control module 10 adjusts the target drive signal based on the pulse drive signal will be discussed later and will not be detailed here.

[0076] The main control module 10 has a voltage regulator circuit inside. Figure 3 (Not shown in the text) The voltage regulator circuit receives the power supply voltage of the working power supply P1 input at the first power supply terminal VIN. The voltage regulator circuit can convert the power supply voltage of the working power supply P1 into a preset drive voltage and output it through the second power supply terminal VCC, thereby enabling the main control module 10 to drive the load. As for the specific value of the preset drive voltage, it can be set according to actual needs, and this application does not limit it.

[0077] exist Figure 3 In the embodiment shown, the second power supply terminal VCC of the main control module 10 is connected to the luminance control terminal DIM, that is, a constant driving voltage is input to the luminance control terminal DIM. In this case, the luminance adjustment function of the main control module 10 can be disabled, and the main control module 10 controls the constant current control circuit 20 to output the maximum operating current, that is, the upper limit of the preset current range.

[0078] As mentioned above, the luminance control terminal DIM of the main control module 10 can receive pulse drive signals. The main control module 10 adjusts the target drive signal based on the pulse drive signals. Based on this, this application embodiment provides another current adjustment circuit, see [link to relevant documentation]. Figure 4 As shown, the current regulation circuit provided in this embodiment also includes a drive circuit 30.

[0079] Combination Figure 4 As shown, the brightness control terminal DIM of the main control module 10 is connected to the output terminal of the drive circuit 30 and the reference power supply P2 respectively. The reference power supply P2 is used to output the base voltage, and the drive circuit 30 is used to output the target pulse control signal. Based on the aforementioned connection relationship, the target pulse control signal will be superimposed on the base voltage, and the signal obtained after superposition is the pulse drive signal.

[0080] It is understandable that the target pulse control signal output by the drive circuit 30 has a preset target duty cycle and voltage amplitude. The base voltage provided by the reference power supply P2 is a DC voltage with a constant amplitude. The pulse drive signal obtained by superimposing the target pulse control signal and the base voltage has the aforementioned target duty cycle, and its voltage amplitude is the sum of the voltage amplitude of the reference voltage and the target pulse control signal. With this setting, the duty cycle of the pulse drive signal finally input to the main control module 10 is controlled by the drive circuit 30, while the voltage amplitude of the pulse drive signal is determined by both. By increasing the voltage amplitude of the pulse drive signal through the reference power supply P2, the performance requirements of the drive circuit 30 can be reduced. In other words, if the drive circuit 30 can provide a target pulse control signal with a sufficient voltage amplitude, the reference power supply P2 can be omitted, and the target pulse control signal provided by the drive circuit 30 can be directly used as the pulse drive signal.

[0081] As for the specific implementation of the reference power supply P2, you can refer to the relevant technologies, which will not be detailed here.

[0082] In practical applications, the drive circuit 30 can adjust the duty cycle of the target pulse control signal it outputs to adjust the pulse drive signal that is finally output to the brightness control terminal DIM of the main control module 10. The main control module 10 adjusts the target drive signal according to the obtained pulse drive signal, thereby adjusting the working process of the constant current control circuit 20.

[0083] In one possible embodiment, see Figure 5 In the embodiment shown, the current regulation circuit provided in this embodiment includes a comparator U1 and a reference circuit 310 in the drive circuit 30.

[0084] Combination Figure 5 As shown, the reference circuit 310 includes a first resistor R1 and a first diode D1. One end of the first resistor R1 is connected to the second power supply terminal VCC of the main control module 10, and the other end of the first resistor R1 is connected to the anode of the first diode D1. The cathode of the first diode D1 is grounded. The connection point between the first resistor R1 and the first diode D1 serves as the output terminal of the reference circuit 310 and is connected to the inverting input terminal of the comparator U1. The non-inverting input terminal of the comparator U1 is used to receive the initial pulse control signal. The output terminal of the comparator U1 serves as the output terminal of the drive circuit 30 and is connected to the brightness control terminal DIM of the main control module 10. In practical applications, the initial pulse drive signal can be provided by a signal module of related technology. This application does not limit the specific source of the initial pulse drive signal.

[0085] Based on the above connection relationship, when the main control module 10 is operating normally, its second power supply terminal VCC outputs a preset driving voltage. This preset driving voltage is greater than the forward voltage of the first diode D1, so the first diode D1 is turned on. Assuming that the forward voltage of the first diode D1 is 0.5V, in this case, the comparator U1 will only output a high level when the voltage amplitude of the initial pulse control signal is greater than 0.5V. Otherwise, the comparator U1 will continue to output a low level. In response to the low level collected by the brightness control terminal DIM, the main control module 10 will disable the constant current control circuit 20 and the main control module 10 will also enter the disabled working mode.

[0086] Therefore, the conduction voltage of the first diode D1 in the reference circuit 310, i.e., the threshold voltage output by the reference circuit 310, is used to verify the validity of the initial pulse control signal obtained from the positive input terminal of the comparator U1. Only when the voltage amplitude of the initial pulse control signal is greater than the threshold voltage will the level output by the comparator U1 change with the duty cycle of the initial pulse control signal. Further, it can be understood that the change in the level output by the comparator U1 with the duty cycle of the initial pulse control signal can be seen as a conversion process of the initial pulse control signal, that is, converting the initial pulse control signal into a target pulse control signal, which is finally output to the brightness control terminal DIM and superimposed on the base voltage provided by the reference power supply P2.

[0087] Figure 5 The composition and operation of other circuits in the current regulation circuit shown can be referred to the relevant content of the foregoing embodiments, and will not be repeated here.

[0088] In one possible embodiment, see Figure 6 As shown, the driving circuit 30 provided in this application may further include a voltage divider circuit 320, which specifically includes a second resistor R2 and a third resistor R3.

[0089] Combination Figure 6 As shown, one end of the second resistor R2 is used to receive the initial pulse control signal, and the other end of the second resistor R2 is connected to one end of the third resistor R3. The other end of the third resistor R3 is grounded, and the connection point of the second resistor R2 and the third resistor R3 is connected to the positive input terminal of the comparator U1.

[0090] Based on the above connection, the voltage divider circuit 320 can divide the voltage amplitude of the initial pulse drive signal, and the voltage across the third resistor R3 is the final voltage amplitude input to the positive input terminal of the comparator U1. The voltage divider circuit 320 reduces the voltage amplitude of the initial pulse control signal, preventing overvoltage damage to the comparator U1 and improving the safety and reliability of the circuit.

[0091] Figure 6The composition and operation of other circuits in the current regulation circuit shown can be referred to the relevant content of the foregoing embodiments, and will not be repeated here.

[0092] In current regulation circuits provided by related technologies, DC / DC chips are typically used for voltage regulation, boosting or bucking the input voltage. Then, operational amplifiers and power transistors are combined to construct a current control circuit, which controls the actual current magnitude based on analog voltage signals. Because the DC / DC chips and operational amplifiers used in these technologies are relatively expensive, the current regulation circuits are costly, have numerous components, and complex circuit structures, resulting in large circuit board sizes. This not only occupies more space but also hinders the miniaturization and integration of lasers.

[0093] Compared to related technologies, the current regulation circuit provided in this application no longer uses a DC / DC chip for voltage control, reducing the use of expensive components. Simultaneously, it simplifies the circuit structure, lowers component procurement costs and reduces additional costs associated with complex circuit design, effectively solving the problem of high costs associated with related technologies and significantly reducing the overall cost of the solution. The simplified circuit structure allows for a substantial reduction in the size of the circuit board, meeting the demands for miniaturization and integration of lasers and enabling the application of lasers in more scenarios with strict size requirements.

[0094] Related technologies suffer from low current regulation accuracy due to limitations such as potentiometer precision. The current detection circuit provided in this application converts the operating current into a sampling voltage signal via a sampling resistor and feeds it back to the main control module. Based on the relationship between the sampling voltage and a preset voltage threshold, the circuit limits the range of the operating current, stabilizing it within the preset current range. This meets the stringent requirements of lasers for current stability, ensuring the normal operation and performance of the laser, and effectively solving the problem of low regulation accuracy in related technologies.

[0095] In one possible embodiment, an adjustable element, such as a sampling resistor, can also be set in the current regulation circuit provided in this application. The user can adjust the specific performance parameters of the adjustable element according to the actual working environment (such as different temperatures, humidity, etc.) and the differences in laser characteristics, so as to better adapt to different working conditions, ensure the stable output of the laser under various conditions, and improve the adaptability and flexibility of the system.

[0096] The optional implementation methods of the main control module involved in each of the above embodiments are described below. As for the relevant contents not explained in this application, they can be implemented with reference to relevant technologies.

[0097] See Figure 7As shown, the main control module includes a current detection circuit, a voltage regulator, a threshold voltage circuit, an over-temperature protection circuit, a comparator U2, a comparator U3, a register U4, a brightness control circuit, and a drive circuit.

[0098] Based on the foregoing, it can be seen that the main control module can output a preset drive voltage through the second power port VCC, possessing a certain load-carrying capacity. This function is achieved through a voltage regulator. Figure 7 As shown, the input terminal of the voltage regulator is connected to the first power supply terminal VIN of the main control module, receiving the operating voltage from the working power supply, converting this operating voltage to obtain the preset drive voltage, and finally outputting it through the second power supply port VCC. Of course, in practical applications, the voltage regulator can also power other modules within the main control module, ensuring the reliable operation of each module.

[0099] The over-temperature protection circuit is used to monitor the operating temperature of the main control module in real time. When the operating temperature exceeds the preset temperature threshold, the over-temperature protection circuit triggers the protection mechanism to adjust the operating status of the main control module or force the main control module to power down, so as to avoid damage to the main control module due to overheating.

[0100] As mentioned earlier, the sampling resistor is connected in series between the first power supply terminal VIN and the sampling terminal CS. Based on this, the current sampling circuit can acquire the voltage across the sampling resistor, i.e., the sampling voltage. Comparators U2 and U3, the seventh resistor R7, and the eighth resistor R8 form a window comparison circuit, and the threshold voltage is provided by the threshold voltage circuit. After the sampling voltage is converted by the seventh resistor R7 and the eighth resistor R8, it is compared with the threshold voltage provided by the threshold voltage circuit. The comparison result is output to register U4, and register U4 finally outputs a PWM signal to the drive circuit, thereby limiting the operating current output by the memory debugging circuit to a preset current range and achieving constant current output.

[0101] Based on the above, it can be seen that the target drive signal output by the main control module is a PWM pulse signal. By adjusting the duty cycle of the PWM pulse signal, the main control module can control the on-time and off-time of the controllable switch Q1, thereby adjusting the actual output operating current. Specifically, when the operating current is lower than the lower limit of the preset current range, the duty cycle of the PWM pulse signal is increased, causing the output operating current to increase; conversely, when the operating current is lower than the lower limit of the preset current range, the duty cycle of the PWM pulse signal is decreased, causing the output operating current to decrease, thus controlling the operating current within the preset current range.

[0102] The brightness control circuit receives pulse drive signals and adjusts the duty cycle of the target drive signal output by the drive circuit according to the obtained pulse drive signals, thereby controlling the working state of the external constant current control circuit and realizing the regulation of the working current.

[0103] In one possible embodiment, this application also provides a laser module, including a laser and a current regulation circuit as provided in any of the foregoing embodiments, wherein the current regulation circuit is electrically connected to the laser and is used to regulate the operating current of the laser.

[0104] Those skilled in the art will understand that the contents disclosed herein can be varied and modified in many ways. For example, the various devices or components described above can be implemented in hardware, or in software, firmware, or a combination of some or all of the three.

[0105] Furthermore, while this disclosure makes various references to certain elements of systems according to embodiments of this disclosure, any number of different elements may be used and operated on clients and / or servers. Elements are merely illustrative, and different aspects of the system and method may use different elements.

[0106] Unless otherwise defined, all terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It should also be understood that terms such as those defined in a common dictionary should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and not as having an idealized or highly formalized meaning, unless expressly defined herein.

[0107] The foregoing description is intended to illustrate the present disclosure and should not be construed as limiting it. While several exemplary embodiments of the present disclosure have been described, those skilled in the art will readily understand that many modifications may be made to the exemplary embodiments without departing from the novel teachings and advantages of the present disclosure. Therefore, all such modifications are intended to be included within the scope of the present disclosure as defined by the claims. It should be understood that the foregoing description is intended to illustrate the present disclosure and should not be construed as limiting it to the specific embodiments disclosed, and modifications to the disclosed embodiments and other embodiments are intended to be included within the scope of the appended claims. The present disclosure is defined by the claims and their equivalents.

Claims

1. A current regulating circuit, characterized by, The current regulation circuit for adjusting the operating current of the laser includes: The main control module includes a first power supply terminal, a sampling terminal, and a constant current control terminal, wherein the first power supply terminal is connected to the working power supply. A sampling resistor is connected between the operating power supply and the sampling terminal of the main control module. The sampling terminal of the main control module is used to acquire the sampling voltage of the sampling resistor. A constant current control circuit includes a controlled terminal and an output terminal. The controlled terminal of the constant current control circuit is connected to the constant current control terminal of the main control module. The main control module is used to obtain a target driving signal based on the sampled voltage and a preset voltage threshold, and input the target driving signal into the controlled terminal of the constant current control circuit. One end of the laser is connected to the output of the constant current control circuit, and the other end is connected to the power supply. The constant current control circuit is used to adjust the operating current of the laser within a preset current range corresponding to the sampling resistor according to the target driving signal.

2. The current regulating circuit of claim 1, wherein, The main control module also includes a luminance control terminal, which is used to receive pulse drive signals, and the main control module adjusts the target drive signal according to the pulse drive signals.

3. The current regulating circuit of claim 2, wherein, Also includes: The driving circuit, in which, The output terminal of the driving circuit is connected to the brightness control terminal and the reference power supply respectively. The reference power supply is used to output the base voltage. The driving circuit is used to output a target pulse control signal, which is superimposed on the base voltage to obtain the pulse driving signal.

4. The current regulating circuit of claim 3, wherein, The driving circuit includes a comparator and a reference circuit, wherein, The positive input terminal of the comparator is used to receive the initial pulse control signal, and the inverting input terminal of the comparator is connected to the output terminal of the reference circuit, which is used to output the threshold voltage. The output of the comparator is connected to the brightness control terminal and the reference power supply, respectively. The comparator is used to output the target pulse control signal based on the initial pulse control signal and the threshold voltage.

5. The current regulating circuit of claim 4, wherein, The main control module also has a second power supply terminal, which is used to output a preset driving voltage. The reference circuit includes a first resistor and a first diode, wherein, One end of the first resistor is connected to the second power supply terminal, and the other end of the first resistor is connected to the anode of the first diode; The cathode of the first diode is grounded; The connection point between the first resistor and the first diode is connected to the inverting input terminal of the comparator.

6. The current regulating circuit of claim 4, wherein, The driving circuit further includes a voltage divider circuit, which comprises a second resistor and a third resistor, wherein... One end of the second resistor is used to receive the initial pulse control signal, and the other end of the second resistor is connected to one end of the third resistor; The other end of the third resistor is grounded; The connection point between the second resistor and the third resistor is connected to the positive input terminal of the comparator.

7. The current regulating circuit according to any one of claims 1 to 6, characterized in that, The constant current control circuit includes: an inductor, a switching circuit, and a unidirectional conduction circuit, wherein... One end of the inductor serves as the output terminal of the constant current control circuit, the other end of the inductor is connected to the first terminal of the switching circuit, and the second terminal of the switching circuit is grounded. The control terminal of the switching circuit serves as the controlled terminal of the constant current control circuit. The connection point between the inductor and the switching circuit is connected to one end of the unidirectional conduction circuit, and the other end of the unidirectional conduction circuit is connected to the first power supply terminal of the main control module. The conduction direction of the unidirectional conduction circuit is the same as the voltage drop direction of the sampling resistor.

8. The current regulating circuit of claim 7, wherein, The switching circuit includes: a controllable switch, a fourth resistor, and a fifth resistor, wherein, One end of the fourth resistor serves as the control terminal of the switching circuit, and the other end of the fourth resistor is connected to one end of the fifth resistor; The other end of the fifth resistor is grounded; The connection point of the fourth resistor and the fifth resistor is connected to the control terminal of the controllable switch; The first end of the controllable switch serves as the first end of the switching circuit, and the second end of the controllable switch serves as the second end of the switching circuit.

9. The current regulating circuit of claim 1, wherein, The main control module also has a luminance control terminal and a second power supply terminal, wherein... The second power supply terminal is used to output a preset drive voltage; When the second power supply terminal is connected to the brightness control terminal, the brightness adjustment function of the main control module is disabled.

10. A laser module, characterized by It includes a laser and a current regulating circuit as described in any one of claims 1 to 9, wherein the current regulating circuit is electrically connected to the laser and is used to regulate the operating current of the laser.

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