Driving circuit of laser and laser control device

Abstract

The utility model discloses a driving circuit of a laser and a laser control device, and relates to the technical field of laser, an input end of an acquisition circuit module is connected with a power supply end of the laser through a driving circuit module, and acquisition voltage corresponding to working current based on the laser is acquired; the control module determines whether the current working current of the laser reaches an expected range according to the acquired voltage, and if the current working current of the laser does not reach the expected range, the control module needs to adjust the driving voltage output by the control module according to the acquired result of the current acquisition circuit module; the driving circuit module can drive the laser to work according to the adjusted driving voltage; the acquisition circuit module monitors the acquisition voltage based on the working current of the laser, and the control module dynamically adjusts the driving voltage according to the monitoring result to form closed-loop control of the laser, so that the driving circuit can control the working current of the laser to be within a preset range, thereby ensuring that the laser can output a stable light source.

Description

Technical Field

[0001] The utility model relates to the technical field of lasers, in particular to a laser driving circuit and a laser control device. Background Art

[0002] With the continuous development of laser technology, the application scenarios of lasers and lasers that generate lasers are becoming more and more extensive. Optical path systems often need to use lasers as light sources to output stable light beams, so the stability of the light source output by the laser is very important. However, in actual applications, when the laser driving circuit is driving the laser to work, factors such as changes in environmental temperature and humidity, interference from other circuits, etc. will greatly affect the stable operation of the driving circuit, causing the laser driven by the driving circuit to be unable to work stably under the expected range of operating current, and the laser will also find it difficult to output a stable light source. Therefore, how to ensure the stability of the light output by the laser has become a technical problem that urgently needs to be solved. Utility Model Content

[0003] The purpose of the utility model is to provide a driving circuit and a laser control device for a laser. The acquisition circuit module monitors the acquisition voltage obtained based on the working current of the laser. At the same time, the control module dynamically adjusts the driving voltage according to the monitoring result, and then adjusts the working current of the laser to form a closed-loop control of the laser, so that the driving circuit can control the working current of the laser within the expected range, thereby ensuring that the laser can output a stable light source.

[0004] In order to solve the above technical problems, the utility model provides a driving circuit of a laser, comprising: a control module, a driving circuit module, and a collection circuit module;

[0005] The acquisition circuit module, whose input end is connected to the driving circuit module, is used to acquire and output to the control module an acquisition voltage based on the working current of the laser;

[0006] The driving circuit module has an input end connected to the output end of the control module and an output end connected to the laser, and is used to receive the driving voltage output by the control module and drive the laser to work based on the driving voltage;

[0007] The control module, whose input end is connected to the output end of the acquisition circuit module, is used to provide a driving voltage to the driving circuit module, receive the acquisition voltage of the acquisition circuit module, and adjust the output driving voltage based on the acquisition voltage so that the operating current of the laser reaches the expected range.

[0008] Optionally, the driving circuit module includes:

[0009] A first operational amplifier, wherein a non-phase input terminal is connected to the output terminal of the control module, and an inverting input terminal is connected to the output terminal of the acquisition circuit module;

[0010] A first resistor has a first end connected to the output end of the first operational amplifier and a second end connected to the positive electrode of the power supply end of the laser, and a negative electrode of the power supply end of the laser is grounded.

[0011] Optionally, the driving circuit module further includes:

[0012] A variable resistor device, wherein the control end is connected to the second end of the first resistor, the first end is connected to the power supply, and the second end is connected to the positive electrode of the power supply end of the laser, and is used to adjust the voltage of the first end and the second end based on the input of the control end, thereby adjusting the working current of the laser.

[0013] Optionally, the variable resistor device is a MOS tube, a gate of the MOS tube is connected to the second end of the first resistor, a drain is connected to a power supply, and a source is connected to a positive electrode of a power supply end of the laser.

[0014] Optionally, the driving circuit module further includes:

[0015] The filter circuit has an input end connected to the output end of the control module, and an output end connected to the non-inverting input end of the first operational amplifier.

[0016] Optionally, the driving circuit module further includes:

[0017] The breakdown protection module has a first end connected to the second end of the variable resistor device and the positive electrode of the power supply end of the laser, and a second end connected to the ground.

[0018] Optionally, the acquisition circuit module includes:

[0019] A sampling resistor, a first end of which is connected to the power supply, and a second end of which is connected to the first end of the variable resistor device;

[0020] The second operational amplifier has a non-phase input terminal connected to the power supply and the first terminal of the sampling resistor respectively, an inverting input terminal connected to the second terminal of the sampling resistor and the first terminal of the variable resistor device respectively, and an output terminal serving as the output terminal of the acquisition circuit module.

[0021] Optionally, the acquisition circuit module further includes:

[0022] a fourth resistor, a first end of which is respectively connected to the second end of the sampling resistor and the first end of the variable resistor device, and a second end of which is connected to the inverting input end of the second operational amplifier;

[0023] A fifth resistor, having a first end connected to the second end of the fourth resistor and the inverting input end of the second operational amplifier respectively, and a second end connected to the output end of the second operational amplifier and the inverting input end of the first operational amplifier respectively.

[0024] In order to solve the above technical problems, the utility model further provides a laser control device, comprising a laser and a driving circuit of the laser as described above, wherein the driving circuit of the laser is connected to a power supply end of the laser.

[0025] The utility model provides a driving circuit of a laser, comprising a collection circuit module, a control module and a driving circuit module. The control module outputs a driving voltage to the driving circuit module. The driving circuit module drives the laser to work according to the driving voltage. The input end of the collection circuit module is connected to the power supply end of the laser through the driving circuit module, and can collect a collection voltage corresponding to the working current of the laser. The control module determines whether the current working current of the laser reaches an expected range according to the collection voltage of the collection circuit module. If the current working current of the laser does not reach the expected range, the control module needs to adjust the driving voltage outputted by itself according to the gap between the collection result of the current collection circuit module and the expected range of the working current of the laser, so that the driving circuit module can drive the laser to work according to the adjusted driving voltage; that is, the collection circuit module monitors the collection voltage corresponding to the working current of the laser, and the control module dynamically adjusts the driving voltage according to the monitoring result, so as to form a closed-loop control of the laser, so that the working current of the laser reaches the expected range, thereby ensuring that the laser can output a stable light source.

[0026] The utility model also provides a laser control device, which has the same beneficial effects as the above laser driving circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the prior art and the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 A schematic diagram of the structure of a laser driving circuit provided by the utility model;

[0029] Figure 2 This is a schematic diagram of the structure of another laser driving circuit provided by the utility model. DETAILED DESCRIPTION

[0030] The core of the utility model is to provide a laser driving circuit and a laser control device. The acquisition circuit module monitors the acquisition voltage obtained based on the working current of the laser. At the same time, the control module dynamically adjusts the driving voltage according to the monitoring result, and then adjusts the working current of the laser to form a closed-loop control of the laser, so that the driving circuit can control the working current of the laser within the expected range, thereby ensuring that the laser can output a stable light source.

[0031] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0032] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a laser driving circuit provided by the utility model; please refer to Figure 2 , Figure 2 This is a schematic diagram of another laser driving circuit provided by the utility model; VCC represents the power supply, which can be implemented with a +5V power supply; AGND represents grounding, and the 1 end of the laser is the positive pole of the power supply end, and the 2 end is the negative pole of the power supply end. In order to solve the above technical problems, the utility model provides a laser driving circuit, including: an acquisition circuit module 1, a control module 2, and a driving circuit module 3;

[0033] The acquisition circuit module 1, whose input end is connected to the driving circuit module 3 and is connected to the laser XP1 through the driving circuit module 3, is used for acquiring and outputting an acquisition voltage based on the working current of the laser XP1 to the control module 2;

[0034] A driving circuit module 3, whose input end is connected to the output end of the control module 2 and whose output end is connected to the laser XP1, is used to receive the driving voltage output by the control module 2 and drive the laser XP1 to work based on the driving voltage;

[0035] The control module 2, whose input end is connected to the output end of the acquisition circuit module 1, is used to provide a driving voltage to the driving circuit module 3, receive the acquisition voltage of the acquisition circuit module 1, and adjust the output driving voltage based on the acquisition voltage so that the operating current of the laser XP1 reaches the expected range.

[0036] It should be noted that the control module 2 outputs a driving voltage to the driving circuit module 3 and then drives the laser XP1 to work, thereby providing an operating current for the laser XP1. However, as the circuit in the driving circuit module 3 is used, due to circuit gain, changes in ambient temperature and humidity, noise, interference from other circuits, etc., the circuit of the driving circuit module 3 may not be completely stable. However, devices or circuits such as particle counters and optical path systems require that the laser XP1 output a sufficiently stable light source. Therefore, it is very important that the output light of the laser XP1, which is the source of the signal, has high stability. Therefore, the present application proposes a solution for monitoring and dynamically adjusting the operating current of the laser XP1.

[0037] It is not difficult to understand that the acquisition circuit module 1 is used to obtain the acquisition voltage corresponding to the actual value of the current working current of the laser XP1, and output the acquisition result to the control module 2. The control module 2 determines whether the current actual working current of the laser XP1 reaches the expected range through the acquisition voltage. At the same time, the acquisition process of the acquisition circuit module 1 is carried out in real time. The control module 2 can further determine whether the actual working current of the laser XP1 is always stable within the expected range. If the actual working current does not reach the expected range or is not always stable within the expected range, the control module 2 needs to adjust the driving voltage output by itself, and control the driving circuit module 3 to drive the laser XP1 to work, and the working current of the laser XP1 can reach the expected range.

[0038] It can be understood that when the control module 2 adjusts the driving voltage output by itself, the specific adjustment method and adjustment value need to be selected and set according to the difference between the actual working current corresponding to the collection voltage and the expected range. The specific implementation method of adjusting the driving voltage of the control module 2 is not particularly limited in this application; the collection circuit module 1 monitors the working current of the laser XP1 in real time by collecting the collection voltage corresponding to the current working current of the laser XP1, and uses the control module 2 to dynamically adjust the working current of the laser XP1 according to the actual value of the laser working current converted by the collection voltage, thereby realizing closed-loop control of the laser XP1. The present application does not make any special limitation on the specific circuit structures of the acquisition circuit module 1, the control module 2 and the drive circuit module 3. There are many implementation methods. In practical applications, an initial drive voltage value is usually assigned to the control module 2 according to the expected range of the working current of the laser XP1 based on experience and the specific setting method of the circuit structure. The control module 2 provides the drive voltage to the drive circuit module 3 according to the initial drive voltage value. The drive circuit module 3 drives the laser XP1 according to the drive voltage to provide the working current for the laser XP1. The acquisition circuit module 1 acquires the voltage across the acquisition resistor connected in series with the laser XP1. The voltage across the processed acquisition resistor is used as the acquisition voltage and transmitted to the control module 2, for example, the voltage across the acquisition resistor is amplified as the acquisition voltage; the control module 2 obtains the actual value of the current working current of the laser XP1 according to the received acquisition voltage; and adjusts the value of the currently output driving voltage according to the actual value of the working current and the expected range of the working current and obtains the updated value of the driving voltage, that is, when the actual value of the working current is not within the expected range of the working current, the value of the currently output driving voltage is adjusted, and then the updated driving voltage is provided to the driving circuit module 3 until the actual value of the laser working current meets the expected range of the working current. Usually, the control module 2 obtains the actual value of the working current by dividing the received acquisition voltage by the resistance proportionality coefficient of the acquisition circuit module 1. The resistance proportionality coefficient of the acquisition circuit module 1 includes but is not limited to the multiplication of the acquisition resistor and the amplification factor of the operational amplifier. For example, when the acquisition circuit module 1 includes an acquisition resistor and an operational amplifier, the amplification factor of the voltage across the acquisition resistor in the specific acquisition circuit module 1 to the output end of the acquisition circuit module 1 can be calculated, which is specifically calculated according to the acquisition circuit and is not specifically explained here. Here, the acquisition circuit module 1 acquires and outputs to the control module an acquisition voltage based on the laser working current, usually by acquiring the voltage across the acquisition resistor connected in series with the laser XP1 and then obtaining the acquisition voltage based on the voltage across the acquisition resistor.The control module 2 can directly convert the actual value of the working current of the laser XP1 based on the collected voltage, thereby judging whether the working current of the laser XP1 reaches expectations. It can also convert the expected range of the working current of the laser XP1 to obtain the expected range of the voltage corresponding to the collected voltage, and use the expected range of the voltage to indirectly judge whether the working current of the laser XP1 reaches expectations.

[0039] Further, based on a driving circuit of a laser XP1 provided in the present application. Before application, the expected range of the working current of the laser XP1 will be set in the control module 2 by means of parameter configuration or the like, and the range can be a specific value or a range interval. Taking the expected range as a specific expected value as an example, the expected value of the working current is defined as the first current I1; the control module 2 outputs the first voltage U1 corresponding to the first current I1 to the driving circuit module 3. From the first current I1 to the first voltage U1, it can be realized by multiplying the first current I1 by the resistance coefficient of the driving circuit module 3 preset in the algorithm. The resistance coefficient of the driving circuit module 3 is calculated and set according to the specific circuit of the driving circuit module 3 that has been designed. It can be the entire circuit loop from outputting the first voltage U1 to the driving circuit module 3 to obtaining the actual value I2 of the working current of the laser XP1 to obtain the equivalent resistance R1, the operational amplifier amplification factor and other calculation parameters, or it can be directly assigned an initial first voltage U1 value to the first current I1 based on experience. The process of the acquisition circuit module 1 outputting the acquisition voltage is specifically implemented based on the method of obtaining the voltage across the acquisition resistor connected in series with the laser XP1. For example, the voltage across the acquisition resistor is obtained and amplified as the acquisition voltage. The acquisition resistor is connected in series with the laser XP1. The acquisition voltage is defined as the second voltage U2. The second voltage U2 is divided by the resistance proportionality coefficient of the acquisition circuit module to obtain the second current I2, that is, the actual value I2 of the working current of the laser XP1. Theoretically, the value of the second current I2 should be consistent with the value of the first current I1, but errors will inevitably be caused by noise, loss, etc. in the circuit. Therefore, the values ​​of the second current I2 and the first current I1 only need to be guaranteed to be within a certain error range to be considered qualified, that is, the second current I2 is required to reach the expected range of the laser working current. The expected range of the laser working current is set based on the floating error of the first current I1 on the premise of meeting the laser working requirements, and the laser XP1 can output stably. The driving circuit module 3 receives the first voltage U1 and outputs it to the laser XP1 to provide the laser XP1 with a working current, i.e., a second current. The acquisition circuit module 1 acquires the voltage across the acquisition resistor connected in series with the laser and amplifies it to obtain a corresponding second voltage and transmits the acquired voltage to the control module 2. The control module 2 converts the received second voltage into a second current, and compares the second current with the expected range of the working current, and adjusts the output first voltage according to the comparison result until the second current meets the expected range of the working current.

[0040] Specifically, the control module 2 may include a main control board including a single-chip microcomputer or a PLC (Programmable Logic Controller), an ADC (analog to digital converter) and a DAC (digital to analog converter) which are separately set or integrated on the single-chip microcomputer or the PLC. When the single-chip microcomputer or the PLC gives the first current an initial first voltage value and outputs the first voltage to the driving circuit module 3 through the DAC, the current transmitted to the laser XP1 after the driving circuit module 3 loops, the acquisition circuit module 1 collects and processes the voltages on both sides of the acquisition resistor connected in series with the laser XP1, and then uses the ADC to convert it into a value corresponding to the second voltage and transmits it to the single-chip microcomputer or the PLC. The single-chip microcomputer or the PLC converts the second current according to the value of the second voltage, and adjusts the output first voltage according to the comparison result of the second current and the expected range of the working current, until the second current meets the expected range of the working current. Here, the value of the first current, the floating error based on the value of the first current, or the expected range of the working current, etc. can all be written in the program.

[0041] Furthermore, the control module 2 may also include a host computer, which can input and configure the value of the first current. The host computer communicates the preset first current value to the single-chip microcomputer or PLC on the main control board and then starts the above-mentioned main control process. Of course, the single-chip microcomputer or PLC can also give the first current an initial first voltage and output the first voltage to the drive circuit module 3 through the DAC. After the drive circuit module 3 loop is formed, a working current is transmitted to the laser XP1. The main control board obtains the value of the second voltage according to the second voltage output by the acquisition circuit module 1 through the ADC and transmits it to the single-chip microcomputer or PLC to obtain the second current, and then transmits the second current to the host computer. The host computer controls the main control board to adjust the first voltage according to the difference between the second current and the first current and the preset error range until the second current signal meets the expected range of the laser working current.

[0042] It is not difficult to understand that, an initial driving voltage value can also be assigned to the control module 2 according to the expected range of the working current of the laser XP1, and the control module 2 provides the driving voltage to the driving circuit module 3 according to the initial driving voltage value, and the driving circuit module 3 drives the laser XP1 according to the driving voltage, so as to provide the working current for the laser XP1; the acquisition circuit module 1 acquires the voltage across the acquisition resistor connected in series with the laser XP1, and uses the processed voltage across the acquisition resistor as the acquisition voltage and transmits it to the control module 2, and the control module 2 determines the expected voltage range of the acquisition voltage corresponding to the received acquisition voltage and the expected range of the laser working current. Whether the acquisition voltage is within the expected voltage range corresponding to the expected range of the laser working current, that is, whether the actual value of the laser working current is within the expected range is judged by judging whether the acquisition voltage is within the expected voltage range corresponding to the expected range of the laser working current. When the acquisition voltage is not within the acquisition voltage range corresponding to the expected range of the laser working current, that is, the actual value of the working current is not within the expected range of the working current, then the value of the currently output driving voltage is adjusted and the updated driving voltage value is obtained. Here, the expected voltage range of the acquisition voltage corresponding to the expected range of the laser working current can be obtained by multiplying the expected range of the working current by the resistance proportional coefficient of the acquisition circuit module 1. Here, the voltage on both sides of the collection resistor connected in series with the laser XP1 in the collection circuit module 1 is collected and processed to output a second voltage, which is converted into a value corresponding to the second voltage by ADC and then transmitted to the single-chip microcomputer or PLC. The single-chip microcomputer or PLC determines whether the second current is within the expected range of the laser working current by judging whether the value of the second voltage is within the expected range of the voltage of the collection voltage corresponding to the expected range of the laser working current, and then adjusts the output first voltage until the second voltage is within the expected range of the voltage of the collection voltage corresponding to the expected range of the laser working current, that is, the second current meets the expected range of the working current.

[0043] The utility model provides a driving circuit of a laser XP1, comprising a collection circuit module 1, a control module 2 and a driving circuit module 3, wherein the control module 2 is electrically connected to the collection circuit module 1 and the driving circuit module 3, the collection circuit module 1 is electrically connected to the driving circuit module 3, an input end of the collection module 1 is connected to a power supply end of the laser XP1 through the driving circuit module 3, an output end of the collection circuit module 1 is connected to an input end of the control module 2, and is used for collecting and outputting a collection voltage based on a working current of the laser to the control module 2, an input end of the driving circuit module 3 is connected to an output end of the control module 2, and is used for receiving a driving voltage output by the control module 2, and driving the laser XP1 to work based on the driving voltage; the control module 2 receives a signal from the collection circuit module 1 according to the output of the control module 2. The collection result determines whether the current working current of laser XP1 reaches the expected range. If the current working current of laser XP1 does not reach the expected range, the control module 2 needs to adjust the driving voltage output by itself according to the gap between the collection result of the current collection circuit module 1 and the expected range, so that the driving circuit module 3 can control the laser XP1 to work within the expected range of the laser working current according to the adjusted driving voltage; the collection circuit module 1 monitors the working current of laser XP1 based on the collection voltage, and the control module 2 dynamically adjusts the driving voltage according to the monitoring result, so as to form a closed-loop control of the laser XP1, so that the laser is within the expected range of the working current, thereby ensuring that the laser XP1 can output a stable light source.

[0044] Based on the above embodiments:

[0045] As an optional embodiment, the driving circuit module 3 includes:

[0046] A first operational amplifier U1, whose non-phase input terminal is connected to the output terminal of the control module 2, and whose inverting input terminal is connected to the output terminal of the acquisition circuit module 1;

[0047] The first resistor R1 has a first end connected to the output end of the first operational amplifier U1 and a second end connected to the positive electrode of the power supply end of the laser XP1. The negative electrode of the power supply end of the laser XP1 is grounded.

[0048] It is understandable that, considering that the driving circuit module 3 needs to provide an effective and reliable working current for the laser XP1 based on the driving voltage output by the control module 2, the present application sets a first operational amplifier U1 in the driving circuit module 3 to process the received driving voltage, so that the driving voltage finally output to the laser XP1 can effectively drive the operation of the laser XP1; the first operational amplifier U1 outputs the processed voltage to the positive electrode of the power supply end of the laser XP1, and the negative electrode of the power supply end of the laser XP1 is grounded, thereby forming a power supply circuit for the driving voltage to power the laser XP1; the positive input end is connected to the output end of the control module 2 to receive the driving voltage output by the control module 2; and the first resistor R1 is also added to further play a role in voltage division and circuit protection. At the same time, the inverting input end of the first operational amplifier U1 is connected to the output end of the acquisition circuit module 1, and the acquisition circuit module 1 constitutes the hardware closure of the entire driving circuit, which is convenient for coordinating with the control module 2 to adjust the driving voltage and realize the dynamic adjustment of the voltage of the driving circuit module 3 at the laser power supply end. The present application does not specifically limit the specific types and implementations of the first operational amplifier U1 and the first resistor R1 .

[0049] Specifically, the driving circuit module 3 includes a first operational amplifier U1 and a first resistor R1, which can effectively amplify the driving voltage and improve the driving capability. At the same time, a first resistor R1 protection circuit is set. The first operational amplifier U1 in the driving circuit module 3 and the acquisition circuit module 1 are further connected through a circuit to form a closed loop of the circuit structure, thereby realizing effective closed-loop control of the laser XP1 with the control module 2.

[0050] As an optional embodiment, the driving circuit module 3 further includes:

[0051] A variable resistor device, wherein the control end is connected to the second end of the first resistor R1, the first end is connected to the power supply, and the second end is connected to the positive electrode of the power supply end of the laser XP1, and is used to adjust the voltage of the first end and the second end thereof based on the input of the control end, thereby adjusting the operating current of the laser XP1.

[0052] It is not difficult to understand that, considering that the driving voltage output by the control module 2 is directly output to the laser XP1 through the first operational amplifier U1 and the first resistor R1, the voltage at the power supply end of the laser XP1 will be affected by the resistance value of the first resistor R1. When the output voltage of the first operational amplifier U1 passes through the first resistor R1, if the resistance value of the first resistor R1 is small, the change of the output end voltage of the first resistor R1 relative to the input end voltage is limited by its own resistance value and will not be very large. The process in which the control module 2 adjusts the voltage at the input end of the laser XP1 by adjusting the driving voltage is greatly affected. Therefore, the present embodiment further adds a variable resistor device, the control end of the variable resistor device is connected to the second end of the first resistor R1, when the voltage of the second end of the first resistor R1 changes with the change of the driving voltage, the variable resistor device will also adjust its own resistance value based on the change of the driving voltage, and at the same time, the second end of the variable resistor device is connected to the positive electrode of the power supply end of the laser XP1, so the change of the resistance value of the variable resistor device will also affect the voltage change of the power supply end of the laser XP1, so on the basis of the change of the driving voltage, the variable resistor device is further used to realize the voltage adjustment process of the power supply end of the laser XP1. The present application does not make any special restrictions on the specific type and implementation method of the variable resistor device.

[0053] Specifically, by adding a variable resistor device, the driving voltage output by the control module 2 can better adjust the voltage at the power supply end of the laser XP1, expand the adjustment range of the driving voltage by the control module 2 and the driving circuit module 3, make the entire adjustment process more flexible, and expand the application range of the entire driving circuit.

[0054] As an optional embodiment, the variable resistance device is a MOS tube Q, the gate of the MOS tube Q is connected to the second end of the first resistor R1, the drain is connected to the power supply, and the source is connected to the positive electrode of the power supply end of the laser XP1.

[0055] It is not difficult to understand that the variable resistor device can be implemented by using a MOS tube Q (Metal-Oxide-Semiconductor Field-Effect Transistor). When the MOS tube Q is in a normally-on state under the action of the driving voltage output by the control module 2 and works in a linear region, the MOS tube Q will cause the current flowing into the gate, that is, the change of the gate voltage, to cause the voltage value at both ends of the drain and source of the MOS tube Q to change, thereby adjusting the voltage change at both ends of the collection resistor and the voltage change at both ends of the laser XP1 to adjust the working current of the laser XP1. The specific type and implementation method of the MOS tube Q are not particularly limited in this application.

[0056] Specifically, the driving voltage output by the control module 2 can be used to make the MOS tube Q work in the linear region, and the variable resistance device is realized by the MOS tube Q working in the variable resistance region. The MOS tube Q itself has a small volume, a small internal resistance, and a fast response speed, which is beneficial to ensure the response speed of the entire adjustment of the working current of the laser XP1 and improve the efficiency of the dynamic adjustment process.

[0057] As an optional embodiment, the driving circuit module 3 further includes:

[0058] The filter circuit has an input end connected to the output end of the control module 2 , and an output end connected to the non-inverting input end of the first operational amplifier U1 .

[0059] It is not difficult to understand that in order to improve the accuracy and reliability of the driving voltage output by the control module 2 to the driving circuit module 3, a filter circuit can be further provided on the input side of the driving circuit module 3 to filter the driving voltage. The specific type and implementation of the filter circuit are not particularly limited in this application. Figure 2 As shown, the filtering circuit specifically includes a first capacitor C1 and a third resistor R3 connected in parallel, the first end of the third resistor R3 and the first end of the first capacitor C1 are connected to the output end of the control module 2 and the non-inverting input end of the first operational amplifier U1, and the second ends of the first capacitor C1 and the third resistor R3 are both grounded.

[0060] Specifically, a filter circuit may be further provided between the control module 2 and the drive circuit module 3 to filter the drive voltage output by the control module 2, thereby improving the accuracy of the drive voltage received by the first operational amplifier U1 and ensuring the accuracy and reliability of the entire drive circuit's adjustment process of the laser XP1's operating current.

[0061] Furthermore, the driving circuit module 3 also includes a second resistor R2, a first end of the second resistor R2 is connected to the output end of the control module 2, and a second end of the second resistor R2 is connected to the first end of the third resistor R3 and the non-phase input end of the first operational amplifier U1, which plays a role of voltage division and further protects the circuit.

[0062] As an optional embodiment, the driving circuit module 3 further includes:

[0063] The breakdown protection module CR1 has a first end connected to the second end of the variable resistor device and the positive electrode of the power supply end of the laser XP1, and a second end connected to the ground.

[0064] It is not difficult to understand that, considering that the working process of the laser XP1 requires a stable driving voltage, a breakdown protection module CR1 on the output side can be further added to the driving circuit module 3. The first end of the breakdown protection module CR1 is connected to the positive electrode of the power supply end of the laser XP1, and the second end is connected to the negative electrode of the power supply end of the laser XP1 and grounded, so as to prevent the laser from being broken down after reverse connection. The specific type and implementation method of the breakdown protection module CR1 are not particularly limited in this application. Figure 2 As shown, it can be realized by using devices such as Schottky diodes.

[0065] Specifically, the reverse breakdown can be prevented by further adding a breakdown protection module CR1, thereby further improving the reliability and safety of the laser XP1; the entire circuit structure is simple and easy to implement, which is conducive to the simple implementation of the entire drive circuit.

[0066] As an optional embodiment, the acquisition circuit module 1 includes:

[0067] A sampling resistor, a first end of which is connected to the power supply, and a second end of which is connected to the first end of the variable resistor device;

[0068] The second operational amplifier U2 has a non-phase input terminal connected to the power supply and the first terminal of the sampling resistor respectively, an inverting input terminal connected to the second terminal of the sampling resistor and the first terminal of the variable resistor device respectively, and an output terminal serving as the output terminal of the acquisition circuit module 1.

[0069] It is not difficult to understand that the sampling resistor is connected in series with the laser XP1, and the control module determines the working current provided by the driving circuit module 3 to the laser XP1 through the sampling resistor connected in series with the driving circuit module 3 in the acquisition circuit module 1, obtains the voltage across the sampling resistor or the voltage after further amplification as the acquisition voltage to detect the working current of the laser XP1, and judges whether the working current of the laser XP1 reaches the expected range; the method of detecting the working current of the laser XP1 through the sampling resistor is easier to implement. At the same time, considering that the control module 2 needs to determine the working current of the laser XP1 by obtaining the voltage across the sampling resistor, and the small working current of the laser will lead to a small voltage across the sampling, the acquisition circuit module 1 needs to further set a second operational amplifier U2 to further amplify the voltage across the sampling resistor to ensure the accurate recognition of the voltage feedback signal by the control module 2, so as to facilitate the control module 2 to receive and directly determine the current working state of the laser XP1 according to the voltage feedback signal; the specific type and implementation method of the sampling resistor and the second operational amplifier U2 are not particularly limited in this application, and the sampling resistor can be obtained by connecting one or more resistors in parallel, such as Figure 2 As shown, the sampling resistor can be realized by two sampling sub-resistors R11 and R22 connected in parallel.

[0070] Specifically, compared with the driving voltage, the sampling resistor can more conveniently obtain the working current of the laser XP1, and can more accurately characterize the current working state of the laser XP1. At the same time, the second operational amplifier U2 is set to facilitate the control module 2 to obtain the accurate current working state of the laser XP1. The entire circuit structure is simple and easy to implement, which is conducive to the simple implementation of the entire driving circuit.

[0071] As an optional embodiment, the acquisition circuit module 1 further includes:

[0072] A fourth resistor R4, a first end of which is respectively connected to the second end of the sampling resistor and the first end of the variable resistor device, and a second end of which is connected to the inverting input end of the second operational amplifier U2;

[0073] The fifth resistor R5 has a first end connected to the second end of the fourth resistor R4 and the inverting input end of the second operational amplifier U2, and a second end connected to the output end of the second operational amplifier U2 and the inverting input end of the first operational amplifier U1.

[0074] It is not difficult to understand that, considering that the second operational amplifier U2 needs to convert the differential signal across the sampling resistor into a single-ended signal of a voltage feedback signal output to the control module 2, it is necessary to further add a peripheral circuit consisting of a fourth resistor R4 and a fifth resistor R5 at the inverting input end of the second operational amplifier U2. The specific types and implementation methods of the fourth resistor R4 and the fifth resistor R5 are not particularly limited in this application.

[0075] Specifically, it is necessary to further set up a peripheral circuit of the second operational amplifier U2 including a fourth resistor R4 and a fifth resistor R5 to facilitate the second operational amplifier U2 to convert differential signals; the entire circuit structure is simple and easy to implement, which is conducive to the simple implementation of the entire drive circuit.

[0076] As an optional embodiment, the acquisition circuit module 1 further includes:

[0077] A sixth resistor R6, a first end of which is respectively connected to the power supply and the first end of the sampling resistor, and a second end of which is connected to the non-inverting input end of the second operational amplifier U2;

[0078] The seventh resistor R7 has a first end connected to the ground, and a second end connected to the second end of the sixth resistor R6 and the non-inverting input end of the second operational amplifier U2 respectively.

[0079] It is not difficult to understand that, considering that the second operational amplifier U2 needs to convert the differential signal across the sampling resistor into a single-ended signal, which is a voltage feedback signal output to the control module 2, it is necessary to add a peripheral circuit consisting of a sixth resistor R6 and a seventh resistor R7 at the non-phase input end of the second operational amplifier U2. The fourth resistor R4, the fifth resistor R5, the sixth resistor R6 and the seventh resistor R7 cooperate so that the second operational amplifier U2 can realize the process of converting the differential signal across the sampling resistor into a single-ended signal. The specific types and implementation methods of the sixth resistor R6 and the seventh resistor R7 are not particularly limited in this application.

[0080] Specifically, it is necessary to further set up a peripheral circuit of the second operational amplifier U2 including a sixth resistor R6 and a seventh resistor R7 to effectively implement the conversion process of the second operational amplifier U2 to the differential signal; the entire circuit structure is simple and easy to implement, which is conducive to the simple implementation of the entire driving circuit.

[0081] As a specific embodiment, the entire driving circuit includes a driving circuit module 3, an acquisition circuit module 1 and a control module 2. The driving circuit module 3 includes a filtering circuit composed of a second resistor R2, a third resistor R3 and a first capacitor C1 as a voltage divider resistor, a first operational amplifier U1, a first resistor R1, a MOS tube Q and a breakdown protection module CR1. A second capacitor C2 is further provided as a peripheral circuit of the first operational amplifier U1. The acquisition circuit module 1 includes a sampling resistor, a second operational amplifier U2 and its peripheral circuit. The sampling resistor is connected in series with the MOS tube Q and cooperates with the second operational amplifier U2 to implement a sampling process of the working current of the laser XP1. The inverting input terminal of the first operational amplifier U1 is connected to the output terminal of the second operational amplifier U2 to form a self-feedback adjustment circuit for the working current of the laser XP1. The VLL_REF terminal serves as a connection terminal between the driving circuit module 3 and the control module 2. After receiving the driving voltage, the VLL_REF terminal provides voltage to the laser XP1 through the voltage-dividing resistor R2, the RC filter, the first operational amplifier U1, the first resistor R1 and the MOS tube Q. The other end of the laser XP1 is grounded. The voltage value at both ends of the source and the drain of the MOS tube Q changes due to the current flowing into the MOS tube Q, thereby adjusting the voltage change at both ends of the acquisition resistor and the voltage change at both ends of the laser XP1 to adjust the working current of the laser XP1. At the same time, the sampling resistor, the MOS tube Q and the laser XP1 are connected in series, and the working current of the laser XP1 is the same as the current flowing through the sampling resistor. At the same time, the control module 2 converts the received voltage at the output end of the second operational amplifier U2 to know whether the working current of the laser XP1 meets the expectation, and changes the voltage at the VLL_REF end to adjust the working current of the laser XP1 to the expected range; when the output voltage at the output end of the second operational amplifier U2 is too large or too small, the input voltage at the inverting input end of the first operational amplifier U1 will also be too large or too small. The large or small input voltage at the inverting input end of the first operational amplifier U1 will cause the input end signal of the first operational amplifier U1 in the driving circuit module 3 to change. At the same time, the driving voltage output by the control module 2 will also cause the voltage at the non-inverting input end of the first operational amplifier U1 to change, and then the voltage at the output end of the first operational amplifier U1 will also change accordingly, thereby controlling the voltage value at both ends of the drain and source of the MOS tube Q to change, resulting in a change in the voltage at both ends of the sampling resistor, and further causing the voltage value at the output end of the second operational amplifier U2 to change, and the control is cyclically controlled until the working current of the laser XP1 reaches the expected working current.

[0082] In order to solve the above technical problems, the utility model further provides a laser control device, including a laser XP1 and a driving circuit of the laser as described above, wherein the driving circuit of the laser is connected to a power supply end of the laser XP1.

[0083] It should be noted that the present application does not make any special limitation on the specific type and implementation of the laser XP1, and there are multiple options for its internal circuit structure, which can be selected and set according to actual application conditions.

[0084] For an introduction to a laser control device provided by the present invention, please refer to the above-mentioned embodiment of the laser driving circuit, and the present invention will not be described in detail here.

[0085] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0086] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0087] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A laser driving circuit, characterized in that: include: Control module, drive circuit module, acquisition circuit module; The acquisition circuit module, whose input end is connected to the driving circuit module, is used to acquire and output to the control module an acquisition voltage based on the working current of the laser; The driving circuit module has an input end connected to the output end of the control module and an output end connected to the laser, and is used to receive the driving voltage output by the control module and drive the laser to work based on the driving voltage; The control module, whose input end is connected to the output end of the acquisition circuit module, is used to provide a driving voltage to the driving circuit module, receive the acquisition voltage of the acquisition circuit module, and adjust the output driving voltage based on the acquisition voltage so that the operating current of the laser reaches the expected range.

2. The laser driving circuit according to claim 1, characterized in that: The driving circuit module comprises: A first operational amplifier, wherein a non-phase input terminal is connected to the output terminal of the control module, and an inverting input terminal is connected to the output terminal of the acquisition circuit module; A first resistor has a first end connected to the output end of the first operational amplifier and a second end connected to the positive electrode of the power supply end of the laser, and a negative electrode of the power supply end of the laser is grounded.

3. The laser driving circuit according to claim 2, characterized in that: The driving circuit module further includes: A variable resistor device, wherein the control end is connected to the second end of the first resistor, the first end is connected to the power supply, and the second end is connected to the positive electrode of the power supply end of the laser, and is used to adjust the voltage of the first end and the second end based on the input of the control end, thereby adjusting the working current of the laser.

4. The laser driving circuit according to claim 3, characterized in that: The variable resistor device is a MOS tube, a gate of the MOS tube is connected to the second end of the first resistor, a drain is connected to a power supply, and a source is connected to the positive electrode of the power supply end of the laser.

5. The laser driving circuit according to claim 3, characterized in that: The driving circuit module further includes: The filter circuit has an input end connected to the output end of the control module, and an output end connected to the non-inverting input end of the first operational amplifier.

6. The laser driving circuit according to claim 3, characterized in that: The driving circuit module further includes: The breakdown protection module has a first end connected to the second end of the variable resistor device and the positive electrode of the power supply end of the laser, and a second end connected to the ground.

7. The laser driving circuit according to any one of claims 3 to 6, characterized in that: The acquisition circuit module comprises: A sampling resistor, a first end of which is connected to the power supply, and a second end of which is connected to the first end of the variable resistor device; The second operational amplifier has a non-phase input terminal connected to the power supply and the first terminal of the sampling resistor respectively, an inverting input terminal connected to the second terminal of the sampling resistor and the first terminal of the variable resistor device respectively, and an output terminal serving as the output terminal of the acquisition circuit module.

8. The laser driving circuit according to claim 7, characterized in that: The acquisition circuit module also includes: a fourth resistor, a first end of which is respectively connected to the second end of the sampling resistor and the first end of the variable resistor device, and a second end of which is connected to the inverting input end of the second operational amplifier; A fifth resistor, having a first end connected to the second end of the fourth resistor and the inverting input end of the second operational amplifier respectively, and a second end connected to the output end of the second operational amplifier and the inverting input end of the first operational amplifier respectively.

9. A laser control device, characterized in that: The invention comprises a laser and a driving circuit of the laser according to any one of claims 1 to 8, wherein the driving circuit of the laser is connected to a power supply terminal of the laser.

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