A laser pump source driving circuit and driver

Abstract

The present application relates to the technical field of pump source driving, and particularly relates to a laser pump source driving circuit and a driver, the laser pump source driving circuit comprising: a rectification and voltage boosting module for rectifying and boosting an alternating current input signal to obtain a corrected and boosted signal; an open loop isolation module for open loop isolation conversion of the corrected and boosted signal to obtain an isolated output voltage; a constant current and voltage reduction adaptive module for adjusting a signal duty cycle of the isolated output voltage and outputting an output current signal to a pump source; the constant current and voltage reduction adaptive module comprising a plurality of voltage reduction constant current driving units, the plurality of voltage reduction constant current driving units being arranged in parallel, each voltage reduction constant current driving unit being connected with the open loop isolation module and connected with the plurality of pump sources one by one. The present application performs fixed ratio voltage conversion through the open loop isolation module, reduces the coupling interference of the voltage loop on the current loop in the subsequent constant current and voltage reduction adaptive module, improves the current loop bandwidth and the system response speed.

Description

Technical Field

[0001] This invention relates to the field of pump source driving technology, and more particularly to a laser pump source driving circuit and driver. Background Technology

[0002] In recent years, laser technology has been widely used in manufacturing, medical, and communication fields. As one of the core components of a laser system, the performance of the laser driver power supply directly affects the performance and lifespan of the laser system.

[0003] Traditional laser pump source pre-stage driver circuits primarily involve an AC / DC power supply that improves the input power factor through PFC (Power Factor Correction), outputting DC power in an isolated DC / DC converter. A closed-loop feedback loop formed by a voltage sampling module stabilizes the isolated DC / DC converter, providing a stable DC voltage for the subsequent linear constant current drive. This constant current is then achieved by controlling the output voltage of the BUCK (step-down) circuit. This circuit consists of three stages of conversion. Its advantages include low requirements for pump source consistency, eliminating the need to select pump sources with identical voltage drops. It also offers fast response, allowing for rapid adjustment during load changes. Disadvantages include increased system complexity, size, and cost. Furthermore, the voltage sampling module can couple with the current control loop of the BUCK circuit, reducing the current control loop bandwidth and consequently decreasing the system response speed.

[0004] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a laser pump source driving circuit and driver to solve the problem that the existing laser pump source system is complex and the coupling interference between the voltage sampling module and the current control loop of the BUCK circuit leads to a reduction in the bandwidth of the current control loop.

[0006] The technical solution of the present invention is as follows: This invention provides a laser pump source driving circuit, comprising: The rectifier-boost module is connected to the AC input signal and is used to rectify and boost the AC input signal to obtain a corrected boost signal. An open-loop isolation module, connected to the rectifier-boost module, is used to perform open-loop isolation transformation on the correction boost signal to obtain an isolated output voltage; The constant current buck adaptive module includes several buck constant current driving units arranged in parallel. Each buck constant current driving unit is connected to the open-loop isolation module and to several pump sources one-to-one. It is used to adjust the signal duty cycle of the isolation output voltage to obtain an output current signal and output it to the pump source.

[0007] In a further embodiment of the present invention, the rectifier boost module includes a bridge rectifier unit and an interleaved boost unit; wherein, The bridge rectifier unit receives an AC input signal and is used to convert the AC input signal into a pulsating DC signal. The interleaved boost unit is connected to the bridge rectifier unit and the open-loop isolation module respectively, and is used to boost the pulsating DC signal to obtain a corrected boost signal and output it to the open-loop isolation module.

[0008] A further embodiment of the present invention includes a filter, wherein the input terminal of the filter is connected to an AC power signal, and the output terminal of the filter is connected to the rectifier-boost module, for performing signal filtering processing on the AC power signal and outputting an AC input signal to the rectifier-boost module.

[0009] In a further embodiment of the present invention, the AC input signal includes a first AC input signal and a second AC input signal; the bridge rectifier unit includes a first diode, a second diode, a third diode, and a fourth diode; wherein, The anode of the first diode and the cathode of the third diode are respectively connected to a first AC input signal, and the cathodes of the first diode and the second diode are respectively connected to the interleaved boost unit; the anode of the second diode and the cathode of the fourth diode are respectively connected to a second AC input signal, and the common terminal of the anodes of the third diode and the fourth diode is grounded.

[0010] In a further embodiment of the present invention, the interleaved boost unit includes: a first inductor, a second inductor, a first field-effect transistor, a second field-effect transistor, a fifth diode, a sixth diode, and a first electrolytic capacitor; wherein, One end of the first inductor and one end of the second inductor are connected to one end of the bridge rectifier unit. The other end of the first inductor is connected to the anode of the fifth diode, and the cathode of the fifth diode is connected to the open-loop isolation module. The other end of the second inductor is connected to the anode of the sixth diode, and the cathode of the sixth diode is connected to the common terminal of the cathode of the fifth diode and the open-loop isolation module. The drain of the first field-effect transistor is connected to the anode of the first inductor and the fifth diode, respectively, and the source of the first field-effect transistor is grounded. The drain of the second field-effect transistor is connected to the anode of the second inductor and the sixth diode, respectively, and the source of the first field-effect transistor is grounded. The positive terminal of the first electrolytic capacitor is connected to the cathode of the fifth diode and the cathode of the sixth diode, respectively, and the negative terminal of the first electrolytic capacitor is grounded.

[0011] In a further embodiment of the present invention, the constant current buck adaptive module includes a plurality of buck constant current driving units, which are arranged in parallel. Each of the buck constant current driving units is connected to the open-loop isolation module and is connected one-to-one with a plurality of pump sources. The step-down constant current drive unit includes a constant current output unit and a step-down feedback control unit. The constant current output unit is connected to the open-loop isolation module and the corresponding pump source, respectively. One end of the step-down feedback control unit is connected to the pump source, and the other end of the step-down feedback control unit is connected to the control terminal of the constant current output unit. It is used to output a constant current control signal to the constant current output unit according to the working current of the pump source. The constant current control signal is used to control the working state of the constant current output unit.

[0012] In a further embodiment of the present invention, the constant current output unit includes: a step-down MOSFET, a step-down inductor, a step-down diode, a first step-down resistor, a second step-down resistor, and a step-down capacitor; wherein, The drain of the step-down MOSFET is connected to the primary terminal of the open-loop isolation module; the source of the step-down MOSFET is connected to one end of the step-down inductor; and the other end of the step-down inductor is connected to the anode of the pump source. The cathode of the step-down diode is connected to the cathode of the step-down MOSFET, and the anode of the step-down diode is connected to the secondary terminal of the open-loop isolation module. One end of the step-down capacitor and one end of the first step-down resistor are connected to the common terminal of the step-down inductor and the pump source, respectively. The other end of the step-down capacitor and the other end of the first step-down resistor are connected to the secondary terminal of the open-loop isolation module. One end of the second step-down resistor is connected to the secondary terminal of the open-loop isolation module, and the other end of the second step-down resistor is connected to the cathode of the pump source.

[0013] In a further embodiment of the present invention, the open-loop isolation module includes a resonant conversion soft-switching unit and a switching signal driving unit; wherein, the switching signal driving unit is connected to the resonant conversion soft-switching unit and is used to generate a predetermined topology control signal and output it to the resonant conversion soft-switching unit; The resonant converter soft-switching unit is connected to the rectifier boost module and the constant current buck adaptive module, respectively, and is used to perform open-loop isolation conversion on the correction boost signal according to the topology control signal to obtain the isolated output voltage and output it to the constant current buck adaptive module.

[0014] In a further embodiment of the present invention, the resonant converter soft-switching unit includes: a third field-effect transistor, a fourth field-effect transistor, a fifth field-effect transistor, a sixth field-effect transistor, a seventh diode, an eighth diode, a third inductor, a first capacitor, a transformer, a ninth diode, and a tenth diode; wherein, The drain of the third field-effect transistor, the drain of the fourth field-effect transistor, and the cathode of the seventh diode are connected to the rectifier boost module. The source of the third field-effect transistor is connected to the drain of the fifth field-effect transistor, and the source of the fourth field-effect transistor is connected to the drain of the sixth field-effect transistor. The sources of the fifth and sixth field-effect transistors are grounded. The anode of the seventh diode is connected to the cathode of the eighth diode, and the anode of the eighth diode is grounded. One end of the third inductor is connected to the source of the fourth field-effect transistor and the drain of the sixth field-effect transistor, respectively. The other end of the third inductor is connected to the anode of the seventh diode and the cathode of the eighth diode, respectively. The first primary terminal of the transformer is connected to the third inductor and the seventh diode, respectively. The second primary terminal of the transformer is connected to one end of the first capacitor, and the other end of the first capacitor is connected to the source of the third field-effect transistor and the drain of the fifth field-effect transistor, respectively. The first stage coil terminal of the transformer is connected to the anode of the ninth diode, the second stage coil terminal of the transformer is connected to the constant current buck adaptive module, the third stage coil terminal of the transformer is connected to the anode of the tenth diode, and the cathode of the tenth diode is connected to the anode of the ninth diode and the constant current buck adaptive module, respectively.

[0015] Based on the same inventive concept, the present invention also provides a driver, wherein the driver is configured with the laser pump source driving circuit described above.

[0016] This invention provides a laser pump source driving circuit and driver. The laser pump source driving circuit includes: a rectification and boost module, which receives an AC input signal and rectifies and boosts the AC input signal to obtain a correction boost signal; an open-loop isolation module, connected to the rectification and boost module, which performs open-loop isolation transformation on the correction boost signal to obtain an isolated output voltage; and a constant-current buck adaptive module, which includes several buck constant-current driving units arranged in parallel. Each buck constant-current driving unit is connected to the open-loop isolation module and to several pump sources one-to-one, for adjusting the signal duty cycle of the isolated output voltage to obtain an output current signal and output it to the pump sources. This invention performs a fixed-ratio voltage transformation through the open-loop isolation module, while reducing the coupling interference of the voltage loop to the current loop in the subsequent constant-current buck adaptive module, thereby improving the current loop bandwidth and system response speed. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the pump source drive circuit of the first prior art.

[0019] Figure 2 This is the circuit schematic of the first existing pump source drive circuit.

[0020] Figure 3 This is a schematic diagram of a pump source drive circuit module of the second prior art.

[0021] Figure 4 This is the circuit diagram of the second type of existing pump source drive circuit.

[0022] Figure 5 This is a schematic diagram of a laser pump source driving circuit in some preferred embodiments of the present invention.

[0023] Figure 6 This is a circuit diagram of the laser pump source driving circuit in this invention.

[0024] The labels in the attached diagram are as follows: 1. Pump source; 100. Rectifier boost module; 110. Bridge rectifier unit; 120. Interleaved boost unit; 200. Open-loop isolation module; 210. Resonant converter soft-switching unit; 220. Switching signal drive unit; 300. Constant current buck adaptive module; 310. Buck constant current drive unit; 311. Constant current output unit; 312. Buck feedback control unit; 400. Filter. Detailed Implementation

[0025] This invention provides a laser pump source driving circuit and driver. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0026] In the implementation methods and claims, unless otherwise specified in the text, the terms "a," "an," "the," and "the" may also include plural forms. If the embodiments of the present invention involve descriptions of "first," "second," etc., such descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.

[0027] It should be further understood that the term "comprising" as used in this specification means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when we say an element is "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements. Furthermore, "connected" or "coupled" as used herein can include wireless connections or wireless coupling. The term "and / or" as used herein includes all or any unit and all combinations of one or more associated listed items.

[0028] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0029] Furthermore, the technical solutions of the various embodiments can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0030] The inventors discovered that the laser pump source driving circuit is used in multi-output adaptive constant current pump source driving devices for multi-module lasers. It is particularly suitable for laser systems requiring multiple pump sources to work collaboratively (e.g., controlling the timing matching of pump pulses and seed light) and where each pump source has a different voltage. It provides independent and precise current control for multiple pump lasers based on the characteristics of different modules. However, in its implementation, due to the different output voltages (i.e., the voltage drop corresponding to the pump source) of each BUCK circuit, their duty cycles differ significantly, resulting in an asynchronous, wide-bandwidth pulsating characteristic in the input current waveform extracted from the common front-end DC / DC converter. This pulsating current in the input current waveform superimposes on the output capacitor of the front-end DC / DC converter, generating complex ripple components, such as the switching frequencies of each BUCK circuit, their difference frequency components, and their sum frequency components. This ripple, as an input voltage disturbance of the BUCK circuit, couples to the output current sampling signal through the small-signal transfer function of the BUCK, forming an additional interference source and thus affecting dynamic response performance.

[0031] Therefore, the first stage of existing pump source drive circuits typically involves an AC input rectified by a bridge rectifier, then processed through an interleaved BOOST PFC topology, resulting in an output voltage of 400V or 800V. The second stage, a DC / DC isolation converter, reduces the 400V or 800V to the voltage required by the pump source for control. For example, such as... Figure 1 and Figure 2 As shown, in the first prior art embodiment, the AC input after filtering is then processed by AC / DC power factor correction and isolated DC / DC converter output. The constant current control of the output current is achieved through the linear region regulation of the MOSFET. Multiple outputs can be achieved through parallel connection of linear constant current sources, such as... Figure 2As shown, the first MOSFET Q1 and the third MOSFET Q3 are the switching transistors of the linear constant current source, while the second MOSFET Q2 and the fourth MOSFET Q4 are the linear regulating transistors. The output constant current section is a linear constant current source, and linear constant current control is achieved by controlling the switching states of the second MOSFET Q2 and the fourth MOSFET Q4. The advantages of this scheme are its simple circuitry, ease of control, low noise, low ripple, high stability, and convenient multi-channel expansion. The disadvantages are that the MOSFETs operating in the linear region have high losses, making thermal design difficult. Multiple MOSFETs operating in the linear region need to be connected in parallel, which may introduce current sharing problems. When the load is 60% of the rated load, the efficiency of the constant current source is lowest and the heat generation is highest. Furthermore, the feedback circuits of each MOSFET require voltage sampling and feedback circuits. This voltage loop is prone to interaction with the current loop during operation, causing interference to the current loop. Also, the multiple pump sources require consistency, necessitating the selection of pump sources with the same voltage drop to form the system.

[0032] In the second existing embodiment, such as Figure 3 and Figure 4 As shown, specifically, the DC / DC voltage constant current source includes an isolated DC / DC converter and a voltage constant current source. The isolated DC / DC converter directly achieves constant current output and adaptively controls the pump source voltage. The voltage constant current source achieves output current control through the isolated DC / DC topology. In this embodiment, each branch is equipped with an isolated DC / DC converter and a voltage constant current source. This scheme has a simpler circuit and higher operating efficiency compared to other existing embodiments. The circuit is concise, with the fewest switching transistors and fewer system stages in single-channel output, resulting in high system integration. The disadvantage of this existing technical solution is that the current rise and fall edge response speed of the current source output is slower than the above scheme. The operating frequency of the DC / DC converter topology limits the bandwidth of the constant current source. When expanding to multiple channels, it is necessary to increase the number of power devices on the primary side and independent control circuits, increasing the size, making the high-voltage circuit more complex, and the drive circuit also relatively complex, making expansion inconvenient.

[0033] To address the problems existing in current technologies, such as Figure 5As shown, the present invention provides a laser pump source driving circuit, comprising: a rectification and boost module 100, which receives an AC input signal and is used to rectify and boost the AC input signal to obtain a correction boost signal; an open-loop isolation module 200, connected to the rectification and boost module 100, which is used to perform open-loop isolation transformation on the correction boost signal to obtain an isolated output voltage; and a constant current buck adaptive module 300, which includes a plurality of buck constant current driving units 310 arranged in parallel, each of which is connected to the open-loop isolation module 200 and connected one-to-one with a plurality of pump sources 1, for adjusting the signal duty cycle of the isolated output voltage to obtain an output current signal and output it to the pump source 1.

[0034] In this preferred embodiment, the laser pump source driving circuit is applied to a multi-output laser pump source 1. Specifically, the working principle of the laser pump source driving circuit is as follows: the rectifier-boost module 100 is used to receive the AC input signal and rectifies and boosts the AC input signal to obtain a corrected boost signal, thereby improving the input power factor. The open-loop isolation module 200 operates in an open-loop fixed duty cycle mode, that is, it uses open-loop control for voltage isolation transformation. It should be noted that in this invention, open-loop means not feeding back the control result to affect the currently controlled system, reducing the interference caused by the voltage loop in the circuit to other circuits, realizing input-output electrical isolation and fixed ratio buck transformation to obtain an isolated output voltage, while simultaneously achieving electrical isolation between the input and output. At the same time, the constant current buck adaptive module 300 is used to adjust the current of the isolated output voltage, thereby controlling the current value output to pump source 1. The constant current buck adaptive module 300 is connected to the open-loop isolation module 200 and to the pump source 1, and includes at least one buck constant current driving unit 310, which can drive at least one pump source 1. Accordingly, one or more buck constant current driving units 310 can be provided, and each buck constant current driving unit 310 is interconnected with the pump source 1. The number of buck constant current driving units 310 can be set according to the number of pump sources 1 or according to the timing sequence. This enables the realization of multiple laser pump source outputs. It should be noted that each of the low buck constant current driving units 310 in this invention has an independently provided current loop, which is used for current sampling and negative feedback control to realize one or more pump source constant current drives and independent closed-loop control. In this preferred embodiment, since the open-loop isolation module 200 operates at a predetermined switching frequency and duty cycle, it can output a stable and reliable isolated output voltage. Furthermore, by using open-loop isolation transformation to simplify the original voltage sampling loop, the matching problem of time constant and phase compensation between the voltage sampling negative feedback loop and the subsequent multi-channel pump source is eliminated. While realizing open-loop control, the coupling interference of the isolation module to the current loop in the subsequent constant current buck adaptive module 300 is reduced, and the current loop bandwidth is improved.

[0035] Please see Figure 5 and Figure 6 In a further embodiment of the preferred embodiment, the rectifier-boost module 100 includes a bridge rectifier unit 110 and an interleaved boost unit 120; wherein, the bridge rectifier unit 110 is connected to an AC input signal and is used to convert the AC input signal into a pulsating DC signal; the interleaved boost unit 120 is connected to the bridge rectifier unit 110 and the open-loop isolation module 200 respectively, and is used to boost the pulsating DC signal to obtain a corrected boost signal and output it to the open-loop isolation module 200.

[0036] The bridge rectifier unit 110 employs a bridge rectifier circuit to convert the AC input signal in AC form into pulsating DC current through AC-DC conversion, thereby providing a base voltage for subsequent stages. This design features a simple structure, high reliability, and reduced circuit complexity. The interleaved boost unit 120 can utilize any existing boost circuit; preferably, it employs an interleaved BOOST PFC boost unit. This interleaved BOOST PFC boost unit utilizes a BOOST (boost) circuit with PFC functionality. The interleaved boost unit 120 is connected to the output of the bridge rectifier unit 110, employing an interleaved parallel boost topology. This topology is used to shape the peak current of the pulsating DC signal into a current following the voltage model, and to boost the rectified pulsating DC current to a preset fixed voltage. This interleaved control improves the system's power factor, reduces input current ripple, enhances conversion efficiency, and reduces transistor current stress. The laser pump source driving circuit may further include a filter 400. The input terminal of the filter 400 is connected to an AC power signal, and the output terminal of the filter 400 is connected to the rectifier-boost module 100. The filter 400 is used to filter the AC power signal and output an AC input signal to the rectifier-boost module 100. The filter 400 is positioned before the bridge rectifier unit 110 to perform preliminary filtering and smoothing of the AC power signal voltage to obtain the AC input signal. This reduces the impact of transient overvoltages such as lightning strikes and surges in the preceding circuit on the bridge rectifier and subsequent circuits, improving system reliability. Simultaneously, it can further suppress common-mode and differential-mode electromagnetic interference from the AC power supply side, preventing external noise from interfering with the normal operation of the driving circuit.

[0037] In some preferred embodiments, the AC input signal includes a first AC input signal L1 and a second AC input signal L2; the bridge rectifier unit 110 includes a first diode D1, a second diode D2, a third diode D3, and a fourth diode D4; wherein the anode of the first diode D1 and the cathode of the third diode D3 are respectively connected to the first AC input signal L1, and the cathodes of the first diode D1 and the second diode D2 are respectively connected to the interleaved boost unit 120; the anode of the second diode D2 and the cathode of the fourth diode D4 are respectively connected to the second AC input signal L2, and the common terminal of the anodes of the third diode D3 and the fourth diode D4 is grounded. The first AC input signal L1 and the second AC input signal L2 are AC inputs provided by an external AC power supply. Preferably, the first AC input signal L1 and the second AC input signal L2 have the same amplitude and frequency, and a phase difference of 180°. The first diode D1, the second diode D2, the third diode D3, and the fourth diode D4 form a full-bridge structure, which ensures that the voltage polarity of the AC input output to the interleaved boost unit 120 in the subsequent circuit is consistent whether the signal is in the positive or negative half-cycle. The frequency of the pulsating DC current is twice the power frequency, and the resulting pulsating DC current signal is used to supply the interleaved boost unit 120 in the subsequent stage as input.

[0038] The interleaved boost unit 120 includes: a first inductor L1a, a second inductor L2a, a first field-effect transistor Q1, a second field-effect transistor Q2, a fifth diode D5, a sixth diode D6, and a first electrolytic capacitor E1; wherein, one end of the first inductor L1a and one end of the second inductor L2a are connected to one end of the bridge rectifier unit 110, the other end of the first inductor L1a is connected to the anode of the fifth diode D5, and the cathode of the fifth diode D5 is connected to the open-loop isolation module 200; the other end of the second inductor L2a is connected to the anode of the sixth diode D6, and the sixth diode D6... The cathode of diode D6 is connected to the common terminal of the cathode of the fifth diode D5 and the open-loop isolation module 200; the drain of the first field-effect transistor Q1 is connected to the anode of the first inductor L1a and the fifth diode D5, respectively, and the source of the first field-effect transistor Q1 is grounded; the drain of the second field-effect transistor Q2 is connected to the anode of the second inductor L2a and the sixth diode D6, respectively, and the source of the first field-effect transistor Q1 is grounded; the positive terminal of the first electrolytic capacitor E1 is connected to the cathode of the fifth diode D5 and the cathode of the sixth diode D6, respectively, and the negative terminal of the first electrolytic capacitor E1 is grounded.

[0039] Specifically, the gate of the first field-effect transistor Q1 is connected to the first boost control signal, and the gate of the second field-effect transistor Q2 is connected to the second boost control signal. The first and second boost control signals can be provided by independent boost signal output modules or by a programmable controller. Specifically, when the interleaved boost unit 120 is working, the phase difference between the first and second boost control signals is 180°. When the first field-effect transistor Q1 is turned on and the second field-effect transistor Q2 is turned off, the first inductor L1a receives the rectified voltage and stores energy, and the fifth diode D5 is reverse-biased and cut off. At this time, the current of the second inductor L2a freewheels through the sixth diode D6, charging the first electrolytic capacitor E1 and supplying the subsequent load. When the first MOSFET Q1 is off and the second MOSFET Q2 is on, the current in the first inductor L1a flows through the fifth diode D5 to charge the first electrolytic capacitor E1, causing the current in the first inductor L1a to decrease linearly. The second inductor L2a bears the rectified voltage and stores energy, while the sixth diode D6 is reverse-biased and cut off. At this time, the input current is mainly provided by the second inductor L2a, and the first inductor L1a provides the output energy. This achieves BOOST boost. Simultaneously, the interleaved boost unit 120 adjusts the duty cycles of the first MOSFET Q1 and the second MOSFET Q2 to ensure that the input current envelope is consistent with the rectified half-sine wave voltage, achieving a power factor as close to 1 as possible. This is used to boost the pulsating DC voltage output from the bridge rectifier to a preset fixed value. Furthermore, by controlling the input current waveform to follow the rectified voltage waveform, high power factor correction is achieved, and interleaved control reduces input current ripple, inductor size, and switching transistor current stress.

[0040] In some preferred embodiments, the open-loop isolation module 200 includes a resonant conversion soft-switching unit 210 and a switching signal driving unit 220; wherein, the switching signal driving unit 220 is connected to the resonant conversion soft-switching unit 210, and is used to generate a predetermined topology control signal and output it to the resonant conversion soft-switching unit 210; the resonant conversion soft-switching unit 210 is connected to the rectifier boost module 100 and the constant current buck adaptive module 300 respectively, and is used to perform open-loop isolation conversion on the correction boost signal according to the topology control signal to obtain the isolated output voltage and output it to the constant current buck adaptive module 300.

[0041] The resonant converter soft-switching unit 210 includes: a third field-effect transistor Q3, a fourth field-effect transistor Q4, a fifth field-effect transistor Q5, a sixth field-effect transistor Q6, a seventh diode D7, an eighth diode D8, a third inductor L3, a first capacitor C1, a transformer T1, a ninth diode D9, and a tenth diode D10; wherein, the drain of the third field-effect transistor Q3, the drain of the fourth field-effect transistor Q4, and the cathode of the seventh diode D7 are connected to the rectifier boost module 100; the source of the third field-effect transistor Q3 is connected to the drain of the fifth field-effect transistor Q5; the source of the fourth field-effect transistor Q4 is connected to the drain of the sixth field-effect transistor Q6; and the sources of the fifth field-effect transistor Q5 and the sixth field-effect transistor Q6 are grounded; the anode of the seventh diode D7 is connected to the cathode of the eighth diode D8; and the anode of the eighth diode D8 is grounded; one end of the third inductor L3 is connected to the fourth field-effect transistor... The source of Q4 is connected to the drain of the sixth field-effect transistor Q6. The other end of the third inductor L3 is connected to the anode of the seventh diode D7 and the cathode of the eighth diode D8, respectively. The first primary terminal of the transformer T1 is connected to the third inductor L3 and the seventh diode D7, respectively. The second primary terminal of the transformer T1 is connected to one end of the first capacitor C1, and the other end of the first capacitor C1 is connected to the source of the third field-effect transistor Q3 and the drain of the fifth field-effect transistor Q5, respectively. The first primary winding terminal of the transformer T1 is connected to the anode of the ninth diode D9, the second primary winding terminal of the transformer T1 is connected to the constant current buck adaptive module 300, the third primary winding terminal of the transformer T1 is connected to the anode of the tenth diode D10, and the cathode of the tenth diode D10 is connected to the anode of the ninth diode D9 and the constant current buck adaptive module 300, respectively.

[0042] Specifically, the resonant converter soft-switching unit 210 adopts a DC / DC full-bridge LC resonant converter soft-switching circuit, and the third field-effect transistor Q3, the fourth field-effect transistor Q4, the fifth field-effect transistor Q5, and the sixth field-effect transistor Q6 form a full-bridge inverter circuit. The topology control signals output by the switching signal driving unit 220 include a first full-bridge driving signal, a second full-bridge driving signal, a third full-bridge driving signal, and a fourth full-bridge driving signal, which are used to control the operating states of the third field-effect transistor Q3, the fourth field-effect transistor Q4, the fifth field-effect transistor Q5, and the sixth field-effect transistor Q6, respectively. The first signal driving terminal of the switch signal driving unit 220 is connected to the gate of the third field-effect transistor Q3 and outputs a first full-bridge driving signal; the second signal driving terminal of the switch signal driving unit 220 is connected to the gate of the fourth field-effect transistor Q4 and outputs a second full-bridge driving signal; the third signal driving terminal of the switch signal driving unit 220 is connected to the gate of the fifth field-effect transistor Q5 and outputs a third full-bridge driving signal; the fourth signal driving terminal of the switch signal driving unit 220 is connected to the gate of the sixth field-effect transistor Q6 and outputs a fourth full-bridge driving signal. The frequencies and duty cycles of the first, second, third, and fourth full-bridge driving signals are predetermined. The third, fourth, fifth, and sixth field-effect transistors Q3, Q4, Q5, and Q6 are alternately turned on under the action of the topology driving signal, inverting the input voltage into a high-frequency AC square wave. The square wave, after passing through the series resonant network formed by the third inductor L3 and the first capacitor C1, generates a near-sinusoidal resonant current injected into the primary side of transformer T1. This resonance enables the switching transistor to operate in a zero-voltage or zero-current soft-switching state, significantly reducing switching losses and electromagnetic interference while achieving electrical isolation between the input and output. Transformer T1 transfers high-frequency energy from the primary side to the secondary side via electromagnetic coupling. Its multiple secondary windings are rectified by the ninth diode D9 and the tenth diode D10, respectively, and output an isolated output voltage to the constant-current buck adaptive module 300. The ninth diode D9 and the tenth diode D10 constitute a full-wave rectifier circuit. The input to the primary winding of transformer T1 is a square wave of high-frequency pulsed AC voltage during both positive and negative half-cycles, while the output of the secondary winding is a positive high-frequency pulsed AC voltage square wave after full-wave rectification. Current flows to the load during both the positive and negative half-cycles of the switching cycle; therefore, the frequency of the isolated output voltage at the secondary side is twice the primary switching frequency, effectively doubling the secondary frequency. Since the module operates in an open-loop state, the output voltage at the secondary end of transformer T1 changes linearly with the input voltage. However, the subsequent constant current buck adaptive module 300 has a wide input adaptive capability and can achieve precise constant current by adjusting its own duty cycle. Therefore, this module does not require feedback adjustment, which ensures high-efficiency isolation transformation while avoiding coupling interference and dynamic response lag caused by the voltage sampling loop.

[0043] Furthermore, the laser pump source driving circuit of the present invention may also include at least one control module (not shown in the figure). The control module may be selected from one or more processor structures such as microcontrollers or programmable controllers. The control module can be connected to the rectifier boost module 100 and the open-loop isolation module 200 to output a first boost control signal and a second boost control signal to the interleaved boost unit 120 to control the interleaved boost unit 120 to boost the pulsating DC signal according to the first boost control signal and the second boost control signal; and output a topology control signal to the resonant converter soft-switching unit 210 to control the resonant converter soft-switching unit 210 to boost the correction boost signal according to the topology control signal.

[0044] In some preferred embodiments, the number of pump sources 1 is equal to the number of buck constant current drive units 310. In this embodiment, the buck constant current drive unit 310 preferably adopts a BUCK current source, that is, the output terminal of the open-loop isolation module 200 is connected to the buck constant current drive unit 310 of the output constant current control section. This scheme facilitates the expansion of multiple outputs. By setting multiple stages of buck constant current drive units 310 after the open-loop isolation module 200 based on isolated DC / DC for BUCK step-down, multiple adaptive current source outputs can be realized. The consistency requirement of the subsequent pump sources 1 is low, and it is not necessary to select pump sources 1 with the same voltage drop to form the system. The response speed is fast, and it can be quickly adjusted when the load changes abruptly.

[0045] For example, such as Figure 5 As shown, this invention takes two parallel buck constant current drive units 310 as an example. At least one of the buck constant current drive units 310 includes a constant current output unit 311 and a buck feedback control unit 312. The constant current output unit 311 is connected to the open-loop isolation module 200 and the corresponding pump source 1, respectively. One end of the buck feedback control unit 312 is connected to the pump source 1, and the other end is connected to the control terminal of the constant current output unit 311. It outputs a constant current control signal to the constant current output unit 311 based on the operating current of the pump source 1. The constant current control signal is used to control the operating state of the constant current output unit 311. The buck feedback control unit 312 can be implemented using an independent signal control unit or through a pre-programmed software in the control module; details are omitted here.

[0046] Furthermore, please refer to the following: Figure 5 and Figure 6 ,by Figure 6Taking the upper constant current output unit 311 as an example, the circuit of the constant current output unit 311 will be described. Among the multiple parallel constant current output units 311, at least one of them includes: a step-down MOSFET Q01, a step-down inductor L01, a step-down diode D01, a first step-down resistor R01, a second step-down resistor R02, and a step-down capacitor C01; wherein, the drain of the step-down MOSFET Q01 is connected to the first stage terminal of the open-loop isolation module 200, the source of the step-down MOSFET Q01 is connected to one end of the step-down inductor L01, and the other end of the step-down inductor L01 is connected to the anode of the pump source 1; the cathode of the step-down diode D01 is connected to the step-down MOSFET... The cathode of the diode Q01 is connected, the anode of the step-down diode D01 is connected to the secondary terminal of the open-loop isolation module 200, one end of the step-down capacitor C01 and one end of the first step-down resistor R01 are respectively connected to the common terminal of the step-down inductor L01 and the pump source 1, the other end of the step-down capacitor C01 and the other end of the first step-down resistor R01 are respectively connected to the secondary terminal of the open-loop isolation module 200; one end of the second step-down resistor R02 is connected to the secondary terminal of the open-loop isolation module 200, and the other end of the second step-down resistor R02 is connected to the cathode of the pump source 1.

[0047] Specifically, one end of the second step-down resistor R02 is connected to the first sampling terminal of the step-down feedback control unit 312, and the other end of the second step-down resistor R02 is connected to the second sampling terminal of the step-down feedback control unit 312. The feedback control terminal of the step-down feedback control unit 312 is connected to the step-down MOSFET Q01. The constant current output unit 311 outputs a precise and stable constant current to the pump source 1 by adjusting the duty cycle of the step-down MOSFET Q01, and realizes multi-channel independent control. In specific implementation, the constant current output unit 311 can be a BUCK current source composed of the step-down MOSFET Q01, the step-down diode D01, and the step-down inductor L01 connected to a single pump source to achieve single-channel output, or it can achieve multi-channel output by connecting several BUCK current sources in parallel after the rectifier output capacitor. It should be noted that each of the parallel constant current output units 311 preferably adopts the same BUCK current source structure as the constant current output unit 311 described in this embodiment, but it can also adopt any other BUCK current source structure, which is not limited here. During operation, each constant current output unit 311 forms a separate BUCK constant current circuit to independently control the output current. By controlling the duty cycle of the step-down MOSFET Q01 in each constant current output unit 311, the output current of each constant current output unit 311 can be controlled, enabling independent adjustment of the output current for each channel. Furthermore, the step-down feedback control unit 312 is used for constant current output. It samples the current of the second step-down resistor R02 to construct a current loop between the second step-down resistor R02 and the step-down MOSFET Q01, thereby achieving precise control of the output current by adjusting the duty cycle of the step-down MOSFET Q01. Specifically, by real-time acquisition of the output current signal at the corresponding second step-down resistor R02 position and feeding it back to the step-down feedback control unit 312, the step-down feedback control unit 312 adjusts the on-time of the corresponding BUCK circuit's switching transistor based on the preset current value and the sampled feedback current signal, achieving independent closed-loop control of the output current for each channel. This reduces the linear constant current source loss while improving efficiency, and also enhances multi-channel expansion performance and response speed. Meanwhile, for different operating scenarios of the load pump source with different voltages, the buck feedback control unit 312 can adaptively adjust the duty cycle of the output constant current control signal so that each BUCK constant current unit can stably output a preset constant current under different output voltages, thereby achieving adaptive constant current drive.

[0048] Based on the same inventive concept, the present invention also provides a driver configured with the laser pump source driving circuit described above. Users can adjust the driver to regulate the operating parameters of the laser pump source driving circuit, thereby adjusting the operating state of the pump light connected to multiple outputs, as specifically described in the embodiments of the laser pump source driving circuit, which will not be repeated here.

[0049] In summary, this invention provides a laser pump source driving circuit and driver. The laser pump source driving circuit includes: a rectification and boost module, which receives an AC input signal and rectifies and boosts the AC input signal to obtain a correction boost signal; an open-loop isolation module, connected to the rectification and boost module, which performs open-loop isolation transformation on the correction boost signal to obtain an isolated output voltage; and a constant-current buck adaptive module, connected to the open-loop isolation module and the pump source, which adjusts the duty cycle of the isolated output voltage to obtain an output current signal and output it to the pump source. The constant-current buck adaptive module includes several buck constant-current driving units arranged in parallel. Each buck constant-current driving unit is connected to the open-loop isolation module and to one-to-one with several pump sources. This invention performs a fixed-ratio voltage transformation through the open-loop isolation module, while reducing the coupling interference of the voltage loop to the current loop in the subsequent constant-current buck adaptive module, thereby improving the current loop bandwidth and system response speed.

[0050] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A laser pump source driving circuit, characterized in that, include: The rectifier-boost module is connected to the AC input voltage and is used to rectify and boost the AC input voltage to obtain a corrected boost signal; An open-loop isolation module, connected to the rectifier-boost module, is used to perform open-loop isolation transformation on the correction boost signal to obtain an isolated output voltage. The open-loop isolation module includes a resonant conversion soft-switching unit and a switching signal driving unit. The switching signal driving unit is connected to the resonant conversion soft-switching unit and is used to generate a predetermined topology control signal and output it to the resonant conversion soft-switching unit. The resonant conversion soft-switching unit is connected to both the rectifier-boost module and the constant-current buck adaptive module, and is used to perform open-loop isolation transformation on the correction boost signal according to the topology control signal to obtain an isolated output voltage and output it to the constant-current buck adaptive module. The open-loop isolation module operates in an open-loop fixed duty cycle mode, using open-loop control for fixed-ratio bucking. The constant current buck adaptive module is connected to the pump source and is used to adjust the signal duty cycle of the isolated output voltage to obtain the output current signal and output it to the pump source.

2. The laser pump source driving circuit according to claim 1, characterized in that, The rectifier boost module includes a bridge rectifier unit and an interleaved boost unit; wherein... The bridge rectifier unit is connected to the AC input voltage and is used to convert the AC signal into a pulsating DC signal. The interleaved boost unit is connected to the bridge rectifier unit and the open-loop isolation module respectively, and is used to boost the pulsating DC signal to obtain a corrected boost signal and output it to the open-loop isolation module.

3. The laser pump source driving circuit according to claim 1, characterized in that, It also includes a filter, the input of which is connected to an AC power signal, and the output of which is connected to the rectifier and boost module. The filter is used to perform signal filtering on the AC power signal and output an AC input voltage to the rectifier and boost module.

4. The laser pump source driving circuit according to claim 2, characterized in that, The bridge rectifier unit includes a first diode, a second diode, a third diode, and a fourth diode; the anode of the first diode and the cathode of the third diode are respectively connected to a first AC input signal, and the cathodes of the first diode and the second diode are respectively connected to the interleaved boost unit; the anode of the second diode and the cathode of the fourth diode are respectively connected to a second AC input signal, and the common terminal of the anodes of the third diode and the fourth diode is grounded; The interleaved boost unit includes: a first inductor, a second inductor, a first field-effect transistor, a second field-effect transistor, a fifth diode, a sixth diode, and a first electrolytic capacitor; wherein, One end of the first inductor and one end of the second inductor are connected to one end of the bridge rectifier unit. The other end of the first inductor is connected to the anode of the fifth diode, and the cathode of the fifth diode is connected to the open-loop isolation module. The other end of the second inductor is connected to the anode of the sixth diode, and the cathode of the sixth diode is connected to the common terminal of the cathode of the fifth diode and the open-loop isolation module. The drain of the first field-effect transistor is connected to the anode of the first inductor and the fifth diode, respectively, and the source of the first field-effect transistor is grounded. The drain of the second field-effect transistor is connected to the anode of the second inductor and the sixth diode, respectively, and the source of the first field-effect transistor is grounded. The positive terminal of the first electrolytic capacitor is connected to the cathode of the fifth diode and the cathode of the sixth diode, respectively, and the negative terminal of the first electrolytic capacitor is grounded.

5. The laser pump source driving circuit according to claim 1, characterized in that, The constant current buck adaptive module includes several buck constant current driving units, which are arranged in parallel. Each buck constant current driving unit is connected to the open-loop isolation module and connected one-to-one with a pump source. The number of pump sources is equal to the number of buck constant current driving units.

6. The laser pump source driving circuit according to claim 5, characterized in that, The step-down constant current drive unit includes a constant current output unit and a step-down feedback control unit. The constant current output unit is connected to the open-loop isolation module and the pump source, respectively. One end of the step-down feedback control unit is connected to the pump source, and the other end of the step-down feedback control unit is connected to the control terminal of the constant current output unit. It is used to output a constant current control signal to the constant current output unit according to the operating current of the pump source. The constant current control signal is used to control the operating state of the constant current output unit.

7. The laser pump source driving circuit according to claim 6, characterized in that, The constant current output unit includes: a step-down MOSFET, a step-down inductor, a step-down diode, a first step-down resistor, a second step-down resistor, and a step-down capacitor; wherein, the drain of the step-down MOSFET is connected to the primary terminal of the open-loop isolation module, the source of the step-down MOSFET is connected to one end of the step-down inductor, and the other end of the step-down inductor is connected to the anode of the pump source; the cathode of the step-down diode is connected to the cathode of the step-down MOSFET, and the anode of the step-down diode is connected to the secondary terminal of the open-loop isolation module; one end of the step-down capacitor and one end of the first step-down resistor are connected to the common terminal of the step-down inductor and the pump source, respectively, and the other end of the step-down capacitor and the other end of the first step-down resistor are connected to the secondary terminal of the open-loop isolation module; one end of the second step-down resistor is connected to the secondary terminal of the open-loop isolation module, and the other end of the second step-down resistor is connected to the cathode of the pump source.

8. The laser pump source driving circuit according to claim 1, characterized in that, The resonant converter soft-switching unit includes: a third field-effect transistor (FET), a fourth field-effect transistor (FET), a fifth field-effect transistor (FET), a sixth field-effect transistor (FET), a seventh diode, an eighth diode, a third inductor, a first capacitor, a first transformer, a ninth diode, and a tenth diode; wherein the drain of the third FET, the drain of the fourth FET, and the cathode of the seventh diode are connected to the rectifier boost module; the source of the third FET is connected to the drain of the fifth FET; the source of the fourth FET is connected to the drain of the sixth FET; and the sources of the fifth and sixth FETs are grounded; the anode of the seventh diode is connected to the cathode of the eighth diode; and the anode of the eighth diode is grounded. One end of the third inductor is connected to the source of the fourth field-effect transistor and the drain of the sixth field-effect transistor, respectively. The other end of the third inductor is connected to the anode of the seventh diode and the cathode of the eighth diode, respectively. The first primary terminal of the first transformer is connected to the third inductor and the seventh diode, respectively. The second primary terminal of the first transformer is connected to one end of the first capacitor, and the other end of the first capacitor is connected to the source of the third field-effect transistor and the drain of the fifth field-effect transistor, respectively. The first primary winding terminal of the first transformer is connected to the anode of the ninth diode, the second primary winding terminal of the first transformer is connected to the constant current buck adaptive module, and the second primary winding terminal of the first transformer is connected to the anode of the tenth diode. The cathode of the tenth diode is connected to the anode of the ninth diode and the constant current buck adaptive module, respectively.

9. A driver, characterized in that, The driver is configured with a laser pump source driving circuit as described in any one of claims 1-8.

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