Output overvoltage protection module applied to laser driving power supply

Abstract

The utility model relates to the technical field of laser driving power supplies, in particular to an output overvoltage protection module applied to a laser driving power supply. The power supply comprises a power supply master control module, a comparison control module and a reset monitoring module. According to the utility model, the input voltage of the laser driving power supply is converted into the driving voltage required by the laser diode through the power supply main control module, the conduction time and frequency of the switching tube are adjusted by using a feedback control mechanism, the stable voltage is output, and the comparison control module samples the output voltage of the laser driving power supply in real time and outputs the output voltage of the laser diode. A sampling voltage signal is compared with a reference voltage, according to a comparison result, an overvoltage protection circuit is utilized to regulate and control a switch tube Q1 of the power supply master control module, and it is guaranteed that when the switch tube Q2 fails and input high voltage is transmitted to a load, the input high voltage can be rapidly cut off, and the effect of protecting the load is achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to laser drive power supply technical field, specifically, relate to an output overvoltage protection module for laser drive power supply. BACKGROUND

[0002] Semiconductor laser is to the semiconductor PN junction direct injection current, realizes particle beam inversion and produces stimulated radiation, utilizes resonant cavity to realize positive feedback, realizes light amplification and produces laser oscillation, has been widely used in laser weapon, laser guidance, laser ranging, industrial welding and cutting and other military and industrial fields, and the voltage of semiconductor laser is self-adaptive characteristic when normally working, is determined by the series LD load, and the stability of injection current directly determines the stability of output optical power.

[0003] The input of the exciting drive power supply is high-voltage battery 540VDC or single-phase / three-phase alternating current, and the LD load voltage is low, so the laser drive power supply usually adopts a BUCK circuit, when the BUCK power mos occurs short circuit or the mos drive circuit is damaged, the input high voltage is transmitted to the LD load, resulting in load damage, in order to prevent the input high voltage from being transmitted to the LD load and protect the load when the BUCK power mos occurs short circuit or the mos drive circuit is damaged, therefore, we provide an output overvoltage protection module for laser drive power supply. UTILITY MODEL CONTENTS

[0004] The utility model discloses a kind of output overvoltage protection modules for laser drive power supply, to solve the problems raised in the above background technology.

[0005] To achieve the above object, the utility model provides an output overvoltage protection module for laser drive power supply, comprising power main control module, comparison control module and reset monitoring module;

[0006] The power main control module utilizes power main control circuit, converts the input voltage of laser drive power supply into the drive voltage required by laser diode, and adjusts the on-time and frequency of switch tube using feedback control mechanism, to output stable voltage;

[0007] The comparison control module samples the output voltage of laser drive power supply in real time, reduces the output voltage according to pre-designed resistance voltage division ratio, obtains a sampling voltage signal proportional to the output voltage, compares the sampling voltage signal with reference voltage, and regulates switch tube Q1 of power main control module using overvoltage protection circuit according to comparison result;

[0008] The reset monitoring module receives overvoltage signals and sampling voltage signals from the comparator by using a digital signal processor, judges the overvoltage state of the laser drive power supply, generates and outputs a reset signal when the reset condition is met, and continuously monitors the output voltage of the laser drive power supply.

[0009] As a further improvement of the technical solution, the power master control module comprises a power master control circuit, wherein the power master control circuit comprises a switch tube Q1, a switch tube Q2, an inductor L1 and a diode D1.

[0010] The drain of the switch tube Q1 is connected to the input voltage VIN, the source of the switch tube Q1 is connected to one end of the capacitor C1 and the driving ground GNDP, and is connected to the drain of the switch tube Q2, the source of the switch tube Q2 is connected to the negative electrode of the diode D1, and is connected to one end of the inductor L1, the other end of the inductor L1 is connected to one end of the capacitor C2, the other end of the capacitor C2 is connected to the positive electrode of the diode D1, the other end of the capacitor C1, and the ground.

[0011] As a further improvement of the technical solution, the comparison control module comprises a voltage sampling unit and an overvoltage protection unit.

[0012] The voltage sampling unit samples the output voltage of the laser drive power supply, and converts the output high voltage into a voltage signal suitable for comparison with the reference voltage in the operational amplifier in proportion;

[0013] The overvoltage protection unit regulates the switch tube Q1 of the power master control circuit according to the comparison result by using the overvoltage protection circuit.

[0014] As a further improvement of the technical solution, the overvoltage protection unit comprises an overvoltage protection circuit, wherein the overvoltage protection circuit comprises a comparator U2, a diode D2, a switch tube Q3 and a semiconductor laser U1.

[0015] The 5th pin of the comparator U2 is connected to one end of the resistor R2, one end of the resistor R4, and the positive electrode of the diode D2, the 6th pin of the comparator U2 is connected to one end of the resistor R1 and one end of the resistor R3, the 7th pin of the comparator U2 is connected to the negative electrode of the diode D2, the gate of the switch tube Q3 and one end of the resistor R5, the drain of the switch tube Q3 is connected to the 2nd pin of the semiconductor laser U1, one end of the resistor R6 is connected to the 1st pin of the semiconductor laser U1, one end of the resistor R7 is connected to the 3rd pin of the semiconductor laser U1, and the 4th pin of the semiconductor laser U1 is connected to the voltage source.

[0016] As a further improvement of the technical solution, the overvoltage protection circuit in the overvoltage protection unit uses resistors R1 and R3 to form a sampling resistor network, and uses resistors R2 and R4 to form a voltage dividing resistor for reference voltage.

[0017] As a further improvement of the technical solution, the reset monitoring module takes the upper and lower threshold of the input voltage as the reset condition, and generates a reset signal when the input voltage exceeds the threshold range.

[0018] Compared with the prior art, the utility model has the advantages of:

[0019] The output overvoltage protection module applied to the laser driving power supply, the power supply main control module converts the input voltage of the laser driving power supply into the driving voltage required by the laser diode, and adjusts the on time and frequency of the switching tube by using the feedback control mechanism, and outputs stable voltage, the comparison control module samples the output voltage of the laser driving power supply in real time, compares the sampling voltage signal with the reference voltage, according to the comparison result, the switching tube Q1 of the power supply main control module is regulated and controlled by using the overvoltage protection circuit, when the switching tube Q2 fails and causes the input high voltage to be transmitted to the load, the input high voltage can be quickly cut off, and the load is protected, the reset monitoring module receives the overvoltage signal and the sampling voltage signal from the comparator by using the digital signal processor, judges the overvoltage state of the laser driving power supply, generates and outputs a reset signal when the reset condition is met, and realizes continuous monitoring of the output voltage of the laser driving power supply. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is the whole flow schematic diagram of the utility model;

[0021] Figure 2 It is the whole detail flow schematic diagram of the utility model;

[0022] Figure 3 It is the power supply main control circuit diagram of the utility model;

[0023] Figure 4 It is the overvoltage protection circuit diagram of the utility model.

[0024] The meaning of each mark in the figure is:

[0025] 100, power supply main control module; 200, comparison control module; 210, voltage sampling unit; 220, overvoltage protection unit; 300, reset monitoring module. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the utility model will be described clearly and completely in combination with the drawings in the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the utility model.

[0027] Semiconductor laser is to semiconductor PN junction direct injection current, realize particle beam inversion and produce stimulated radiation, and then use resonant cavity to realize positive feedback, realize optical amplification and produce laser oscillation, which has been widely used in laser weapon, laser guidance, laser ranging, industrial welding and cutting and other military and industrial fields, the voltage of semiconductor laser is self-adaptive characteristic when it works normally, which is determined by the series LD load, and the stability of the injected current directly determines the stability of the output optical power.

[0028] As shown in Figure 1 The utility model provides an output overvoltage protection module for laser drive power supply, including power main control module 100, comparison control module 200 and reset monitoring module 300;

[0029] Power main control module 100 utilizes power main control circuit, converts the input voltage of laser drive power supply into the drive voltage required by laser diode, and utilizes feedback control mechanism to adjust the on-time and frequency of switch tube, and outputs stable voltage;

[0030] Comparison control module 200 samples the output voltage of laser drive power supply in real time, reduces the output voltage according to the resistance voltage division ratio designed in advance, obtains a sampling voltage signal proportional to the output voltage, compares the sampling voltage signal with reference voltage, according to the comparison result, utilizes overvoltage protection circuit to regulate and control switch tube Q1 of power main control module 100;

[0031] Reset monitoring module 300 utilizes digital signal processor to receive overvoltage signal and sampling voltage signal from comparator, judges the overvoltage state of laser drive power supply, generates and outputs reset signal when meeting reset condition, and continuously monitors the output voltage of laser drive power supply.

[0032] The power main control circuit adopts BUCK circuit, also called voltage reduction chopper circuit, which is a common DC-DC conversion circuit, and the main function is to convert higher DC input voltage into lower DC output voltage, and the output voltage can be adjusted according to the needs through the control circuit. For example, in some electronic devices, the power adapter inputs higher DC voltage, such as 12V or 24V, while the internal electronic components may only need 3.3V or 5V working voltage, at this time, BUCK circuit can be used to reduce the input voltage to the appropriate level, and provide stable power supply for circuits or devices with different voltage requirements.

[0033] As shown in Figure 3 The power main control module 100 includes a power main control circuit, wherein the power main control circuit includes a switch tube Q1, a switch tube Q2, an inductor L1 and a diode D1.

[0034] The drain of the switch tube Q1 is connected to the input voltage VIN, the source of the switch tube Q1 is connected to one end of the capacitor C1 and the driving ground GNDP, and is connected to the drain of the switch tube Q2, the source of the switch tube Q2 is connected to the negative electrode of the diode D1, and is connected to one end of the inductor L1, the other end of the inductor L1 is connected to one end of the capacitor C2, the other end of the capacitor C2 is connected to the positive electrode of the diode D1, the other end of the capacitor C1, and the ground.

[0035] In the circuit, when the switch tube Q2 receives a high-level control signal and is turned on, the power supply charges the inductor L1 through the switch tube Q2, and the inductor L1 current rises linearly, at this time, the diode D1 is in a reverse blocking state, the capacitor C1 discharges to the load to maintain the output voltage, after the switch tube Q2 receives a low-level signal and is turned off, the current in the inductor L1 cannot be abruptly changed, the inductor L1 generates a reverse electromotive force, so that the diode D1 is forwardly conducted, the inductor L1 releases energy to the capacitor C1 and the load through the diode D1, the inductor L1 current linearly decreases, the capacitor C1 is charged, and continues to provide current to the load.

[0036] As shown in Figure 2 , wherein the comparison control module 200 comprises a voltage sampling unit 210 and an overvoltage protection unit 220;

[0037] The voltage sampling unit 210 samples the output voltage of the laser drive power supply, and converts the output high voltage into a voltage signal suitable for comparison with the reference voltage in the operational amplifier in proportion;

[0038] The overvoltage protection unit 220 regulates the switch tube Q1 of the power supply main control circuit according to the comparison result by using the overvoltage protection circuit;

[0039] The output voltage of the laser drive power supply is sampled in real time, and the output voltage is stepped down according to the pre-designed resistance voltage division ratio to obtain a sampling voltage signal proportional to the output voltage, and is transmitted to the operational amplifier. The operational amplifier amplifies and conditions the input sampling voltage signal, amplifies the sampling voltage according to the amplification multiple of the circuit design, and at the same time can filter, denoise and other treatments on the signal through feedback, so that the sampling voltage signal is more stable and accurate, and then outputs the processed signal to the comparator.

[0040] As shown in Figure 4 , wherein the overvoltage protection unit 220 comprises an overvoltage protection circuit, and the overvoltage protection circuit comprises a comparator U2, a diode D2, a switch tube Q3 and a semiconductor laser U1.

[0041] One end of the 5-pin resistor R2 of the comparator U2, one end of the resistor R4, and the positive electrode of the diode D2 are connected. One end of the 6-pin resistor R1 of the comparator U2, one end of the resistor R3, and the positive electrode of the diode D2 are connected. The 7-pin of the comparator U2 is connected to the gate of the switch tube Q3 and one end of the resistor R5, and the negative electrode of the diode D2. The drain of the switch tube Q3 is connected to the 2-pin of the semiconductor laser U1. One end of the resistor R6 is connected to the 1-pin of the semiconductor laser U1. One end of the resistor R7 is connected to the 3-pin of the semiconductor laser U1. The 4-pin of the semiconductor laser U1 is connected to the voltage source.

[0042] In the circuit, when the output voltage is lower than the protection value, that is, the voltage of the 6-pin of the comparator U2 is lower than the voltage of the 5-pin, the comparator U2 outputs a high level, the switch tube Q3 is turned on, the primary of the semiconductor laser U1 is turned on, and the secondary of the semiconductor laser U1 is turned on. The output is high, the switch tube Q1 is turned on, and the power supply works normally. When the switch tube Q2 fails, the output high voltage reaches VOUT. When the VOUT voltage rises to the protection setting value, that is, the voltage of the 6-pin of the comparator U2 is higher than the voltage of the 5-pin, the 7-pin of the comparator U2 outputs a low level, the switch tube Q3 stops conducting, the primary of the semiconductor laser U1 stops conducting, the secondary of the semiconductor laser U1 stops conducting, the output is low, and the switch tube Q1 is disconnected. At this time, the input high voltage is disconnected from the power supply, which plays a role in protecting the load.

[0043] In order to better sample the output voltage of the laser drive power supply and determine the reference voltage, the overvoltage protection circuit in the overvoltage protection unit 220 uses resistors R1 and R3 to form a sampling resistor network, and uses resistors R2 and R4 to form a reference voltage dividing resistor.

[0044] The output voltage of the laser drive power supply is sampled by resistors R1 and R3, and the output high voltage is converted into a lower voltage signal suitable for subsequent circuit processing according to a certain proportion, so as to be compared with the reference voltage. The ratio of resistors R2 and R4 is set to accurately set a stable reference voltage as a reference standard for judging whether the output voltage is overvoltage.

[0045] In order to be able to generate a reset signal more quickly, the reset monitoring module 300 uses the upper and lower threshold values of the input voltage as the reset condition, and generates a reset signal when the input voltage exceeds the threshold range.

[0046] The digital signal processor analyzes and processes these signals through internal software programs. After detecting the overvoltage condition and triggering the protection action, the software program starts to monitor the voltage sampling signal to determine whether the overvoltage is eliminated. Once it is determined that the overvoltage is eliminated, the software program outputs a reset signal to the protection execution circuit and other modules through the control pin to realize automatic reset, and starts the relevant program to restart monitoring and analyzing the output voltage of the laser drive power supply.

[0047] During the over-voltage state, the reset decision module continuously monitors the voltage sampling value. When the voltage sampling value is lower than the over-voltage threshold value and lasts for a period of time (for example, 500 milliseconds), or other preset reset conditions are met (such as the voltage change rate being within a certain range), the reset decision module determines that the over-voltage condition has been eliminated and decides to perform a reset operation.

[0048] The output voltage of the BUCK circuit is monitored. If the output voltage deviates from the set value by more than a certain range or appears long-term unstable fluctuations, it may indicate that the circuit has a fault or an abnormality. For example, the set output voltage is 12V, and the allowable fluctuation range is ±0.5V. When the output voltage exceeds the range of 11.5V-12.5V and lasts for a certain time (for example, 50ms), a reset is triggered.

[0049] In summary, the working principle of the present scheme is as follows:

[0050] In the output over-voltage protection module applied to the laser driving power supply, the power supply main control module 100 converts the input voltage of the laser driving power supply into the driving voltage required by the laser diode, and adjusts the on-time and frequency of the switching tube by using a feedback control mechanism to output a stable voltage. The comparison control module 200 samples the output voltage of the laser driving power supply in real time, compares the sampled voltage signal with the reference voltage, and according to the comparison result, uses the over-voltage protection circuit to regulate and control the switching tube Q1 of the power supply main control module 100, so as to ensure that when the switching tube Q2 fails and causes the input high voltage to be transmitted to the load, the input high voltage can be quickly cut off, thereby protecting the load. The reset monitoring module 300 receives the over-voltage signal and the sampled voltage signal from the comparator by using a digital signal processor, judges the over-voltage state of the laser driving power supply, generates and outputs a reset signal when the reset condition is met, and realizes continuous monitoring of the output voltage of the laser driving power supply.

[0051] The basic principle, main features and advantages of the present application are shown and described above. Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and descriptions in the specification are only preferred examples of the present application and do not limit the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. An output overvoltage protection module applied to a laser driving power supply, characterized in that: The power supply master control module (100), the comparison control module (200) and the reset monitoring module (300) are included. The power supply master control module (100) utilizes the power supply master control circuit to convert the input voltage of the laser drive power supply into the driving voltage required by the laser diode, and utilizes the feedback control mechanism to adjust the on-time and frequency of the switch tube, and outputs stable voltage. The comparison control module (200) samples the output voltage of the laser drive power supply in real time, reduces the voltage according to the pre-designed resistance voltage division ratio, obtains a sampling voltage signal proportional to the output voltage, compares the sampling voltage signal with the reference voltage, and according to the comparison result, utilizes the overvoltage protection circuit to regulate the switch tube Q1 of the power supply master control module (100). The reset monitoring module (300) utilizes the digital signal processor to receive the overvoltage signal and the sampling voltage signal from the comparator, judges the overvoltage state of the laser drive power supply, generates and outputs the reset signal when the reset condition is met, and continuously monitors the output voltage of the laser drive power supply.

2. The output overvoltage protection module for laser driving power supply according to claim 1, characterized in that: The power supply master control module (100) includes the power supply master control circuit, wherein the power supply master control circuit includes the switch tube Q1, the switch tube Q2, the inductor L1 and the diode D1. The drain of the switch tube Q1 is connected with the input voltage VIN, the source of the switch tube Q1 is connected with one end of the capacitor C1 and the driving ground GNDP, and is connected with the drain of the switch tube Q2, the source of the switch tube Q2 is connected with the negative electrode of the diode D1, and is connected with one end of the inductor L1, the other end of the inductor L1 is connected with one end of the capacitor C2, the other end of the capacitor C2 is connected with the positive electrode of the diode D1, the other end of the capacitor C1, and the ground.

3. The output overvoltage protection module for laser driver power supply according to claim 1, characterized in that: The comparison control module (200) includes the voltage sampling unit (210) and the overvoltage protection unit (220). The voltage sampling unit (210) samples the output voltage of the laser drive power supply, converts the output high voltage into a voltage signal suitable for comparison with the reference voltage in the operational amplifier according to the proportion; The overvoltage protection unit (220) regulates the switch tube Q1 of the power supply master control circuit according to the comparison result, utilizing the overvoltage protection circuit.

4. The output overvoltage protection module for laser driver power supply according to claim 3, characterized in that: The overvoltage protection unit (220) includes the overvoltage protection circuit, wherein the overvoltage protection circuit includes the comparator U2, the diode D2, the switch tube Q3 and the semiconductor laser U1. The 5th pin of the comparator U2 is connected with one end of the resistor R2, one end of the resistor R4, and the positive electrode of the diode D2, the 6th pin of the comparator U2 is connected with one end of the resistor R1 and one end of the resistor R3, the 7th pin of the comparator U2 is connected with the negative electrode of the diode D2, the gate of the switch tube Q3 and one end of the resistor R5, the drain of the switch tube Q3 is connected with the 2nd pin of the semiconductor laser U1, one end of the resistor R6 is connected with the 1st pin of the semiconductor laser U1, one end of the resistor R7 is connected with the 3rd pin of the semiconductor laser U1, and the 4th pin of the semiconductor laser U1 is connected with the voltage source.

5. The output overvoltage protection module for laser driver power supply according to claim 4, characterized in that: The overvoltage protection circuit in the overvoltage protection unit (220) uses resistors R1 and R3 to form a sampling resistor network, and uses resistors R2 and R4 to form a reference voltage voltage dividing resistor.

6. The output over-voltage protection module for laser driver power supply according to claim 1, characterized in that: The reset monitoring module (300) uses upper and lower threshold values of the input voltage as reset conditions, and generates a reset signal when the input voltage exceeds the threshold range.

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