CN220086616U - Circuit structure for realizing current protection of double-pump laser - Google Patents

Abstract

The utility model relates to a circuit structure for realizing double-pumping laser current protection, which comprises a first pumping circuit module, a second pumping circuit module, a third current sampling resistor, a third current sampling amplifying operational amplifier module and an integral amplifying operational amplifier module, wherein the circuit structures of the first pumping circuit module and the second pumping circuit module are the same, the output end of the first pumping circuit module and the output end of the second pumping circuit module are connected with the third current sampling resistor, the other end of the third current sampling amplifying operational amplifier module is connected with the integral amplifying operational amplifier module, and the other end of the integral amplifying operational amplifier module is connected with the variable resistor areas of the first pumping circuit module and the second pumping circuit module. By adopting the circuit structure for realizing the current protection of the double-pumping laser, the reliability and the low failure of the laser module are improved, the total current output of the double pumping can be still restrained on the premise of master control failure, and the hardware limiting function of the pumping current and the double laser generation protection function are realized.

Description

Circuit structure for realizing current protection of double-pump laser

Technical Field

The utility model relates to the field of lasers, in particular to the field of current protection circuits of laser light source generating circuits, and specifically relates to a circuit structure for realizing current protection of double-pump lasers.

Background

Semiconductor lasers have been widely used in the communication field, medical field, military field, industrial field, and the like. However, a great feature of the laser is that the power density is very high, and although one use of the laser is mainly applied in a form of short-time pulse to avoid damage to equipment and human body caused by excessive power, it is dangerous that the output power of the laser is uncontrollable if the light source of the laser is abnormal. Further, laser generation in order to increase the efficiency and lifetime of laser conversion, the design of dual pumping is a new and unique design scheme, but this new and unique design, while solving the problems of laser conversion efficiency and lifetime, causes higher regulatory requirements for higher laser safety designs. It is necessary to introduce a separate current protection circuit for the laser generating circuit.

Disclosure of Invention

The utility model aims to overcome the defects of the prior art and provide a circuit structure which has high laser conversion efficiency, long service life and good safety and realizes the current protection of double-pump laser.

In order to achieve the above object, the circuit structure for realizing the current protection of the dual pump laser of the present utility model is as follows:

the circuit structure for realizing the double-pump laser current protection is mainly characterized by comprising a first pump circuit module, a second pump circuit module, a third current sampling resistor, a third current sampling amplifying operation amplifier module and an integral amplifying operation amplifier module, wherein the circuit structures of the first pump circuit module and the second pump circuit module are the same, the output end of the first pump circuit module and the output end of the second pump circuit module are connected with the third current sampling resistor, one end of the third current sampling amplifying operation amplifier module is connected with the third current sampling resistor, the other end of the third current sampling amplifying operation amplifier module is connected with the integral amplifying operation amplifier module, and the other end of the integral amplifying operation amplifier module is connected with the variable resistor areas of the first pump circuit module and the second pump circuit module.

Preferably, the first pumping circuit module comprises a bias resistor, a third MOS tube, a current adjusting operational amplifier module, a current sampling amplifying operational amplifier module, a DC-DC module, a pumping laser luminotron, a current sampling resistor and a first MOS tube,

the input end of the bias resistor is connected with the digital-analog converter at the front end, the drain electrode of the third MOS tube is connected with the bias resistor, the source electrode of the third MOS tube is grounded, the grid electrode of the third MOS tube of the first pumping circuit module is connected with the grid electrode of the third MOS tube of the second pumping circuit module, one end of the current regulation operational amplifier module is connected with the bias resistor and the drain electrode of the third MOS tube, the other end of the current regulation operational amplifier module is respectively connected with the current sampling amplification operational amplifier module and the DC-DC module, the other end of the DC-DC module is connected with the positive electrode of the pumping laser luminous tube, the negative electrode of the pumping laser luminous tube is connected with the current sampling resistor, the two ends of the output end of the current sampling amplification operational amplifier module are connected with the two ends of the current sampling resistor, the output end of the current sampling resistor is connected with the drain electrode of the first MOS tube, the source electrode of the first MOS tube is connected with the third current sampling resistor, and the grid electrode of the first MOS tube is connected with an external control signal.

Preferably, the resistances of the current sampling resistors of the first pumping circuit module and the second pumping circuit module are the same.

Preferably, the circuit structure further comprises a power interface filter circuit, the power interface filter circuit comprises a current protection and overvoltage protection unit, an initial power supply port filter unit and a power supply state indication unit, the current protection and overvoltage protection unit comprises a fuse and a TVS tube, the initial power supply port filter unit comprises a common mode inductor and a plurality of capacitors, the power supply state indication unit comprises a sixth seventh resistor and a first light emitting diode, the fuse is connected with an input power supply, the TVS tube is connected with the fuse, the capacitors are connected at two ends of the common mode inductor in parallel, the sixth seventh resistor is connected with the initial power supply port filter unit, and the first light emitting diode is connected at two ends of the initial power supply port filter unit in parallel.

Preferably, the circuit structure further comprises a power supply conversion circuit, the power supply conversion circuit comprises an LDO linear voltage stabilizer, a linear voltage stabilizer filtering unit and a voltage conversion functional unit, the linear voltage stabilizer filtering unit comprises a plurality of capacitors and magnetic beads, the capacitors are respectively connected with ports of the LDO linear voltage stabilizer, the magnetic beads are connected with input ends of the LDO linear voltage stabilizer, and the voltage conversion functional unit is connected with the LDO linear voltage stabilizer.

Preferably, the circuit structure further comprises a high-low power pumping switching circuit, the high-low power pumping switching circuit comprises a PWM (pulse-width modulation) conversion DAC (digital-to-analog converter) unit, an analog switch and an analog switch filtering decoupling unit, the output end of the PWM conversion DAC unit is connected with the analog switch, and the analog switch filtering decoupling unit is connected with the analog switch.

Preferably, the circuit structure further comprises a pumping current regulating circuit connected with the high-low power pumping switching circuit, the pumping current regulating circuit comprises a DAC signal regulating unit and a closed-loop control unit, the DAC signal regulating unit is connected with the analog switch, and the closed-loop control unit is connected with the DAC signal regulating unit.

Preferably, the circuit structure further comprises a DC-DC output circuit, the DC-DC output circuit comprises a DC-DC chip, a DC-DC chip filtering decoupling unit, a fourth third sampling resistor and a current-voltage conversion unit, the DC-DC chip filtering decoupling unit and the fourth third sampling resistor are connected with the DC-DC chip, and the current-voltage conversion unit is connected with the fourth third sampling resistor and the DC-DC chip.

Preferably, the circuit structure further comprises a single-path pumping current detection circuit connected with the DC-DC output circuit, the single-path pumping current detection circuit comprises a pumping unit and a pumping switching control unit, the pumping unit is connected with the DC-DC output circuit, and the pumping switching control unit is connected with the pumping unit.

Preferably, the circuit structure further comprises a double-pumping total current detection circuit and an integral control circuit, the double-pumping total current detection circuit and the integral control circuit comprise a fifth third current sampling resistor and a current-voltage conversion unit of the fifth third current sampling resistor, the circuit structure further comprises a tenth operational amplifier and an output limiting unit of the tenth operational amplifier, and the output limiting unit of the tenth operational amplifier is connected with the current-voltage conversion unit of the fifth third current sampling resistor.

By adopting the circuit structure for realizing the current protection of the double-pump laser, the double pumps can output high-power laser without pumping with high power, and meanwhile, the problem of too short service life of the laser caused by pumping loss and aging is avoided. When a single pump fails, another pump can work, so that the phenomenon that the laser module fails directly and cannot work is avoided. The reliability and low failure property of the laser module are improved. The double pumps can realize the interval switching work and the extension of the service life of the pump body, and finally the whole service life of the laser module is prolonged. Each of the two pumps has an independent current detection, and the value of the current detection can be fed back to the main control. The total current of the double pumping current is provided with an independent current detection functional unit, so that the double pumping total current can still be detected under the condition of double pumping failure; and further the control of the double-pump total current output at a fixed value is suppressed by the feedback function. The current protection circuit can still inhibit the total current output of double pumps on the premise of master control failure, and realizes the hardware limiting function of pumping current; the current protection circuit can still feed back to the main control under the premise that one path of the double-pump circuit fails, and can still continue to work under the premise that the other path of the double-pump circuit fails. The power of the laser generator is completely controllable, and the power output of the laser generator can still be ensured not to exceed a set value on the premise of device failure or main control failure, so that the laser output power is limited at a fixed value, and laser receiving equipment or objects can not be burnt or damaged. Thereby realizing the dual laser generation protection function.

Drawings

Fig. 1 is a circuit configuration diagram of a circuit structure for realizing current protection of a dual pump laser according to the present utility model.

Fig. 2 is an overall circuit diagram of a circuit structure for realizing the current protection of the dual pump laser according to the present utility model.

Fig. 3 is a schematic diagram of a power interface filter circuit of the circuit structure for implementing current protection of the dual pump laser according to the present utility model.

Fig. 4 is a schematic diagram of a 3.3V power conversion circuit of the circuit structure for implementing current protection of the dual pump laser according to the present utility model.

Fig. 5 is a schematic diagram of a high-low power pump switching circuit and a pump current adjusting circuit of a circuit structure for implementing current protection of a dual pump laser according to the present utility model.

Fig. 6 is a schematic diagram of a DC-DC output circuit and a single-pump current detection circuit of a circuit structure for implementing current protection of a dual-pump laser according to the present utility model.

Fig. 7 is a schematic diagram of a dual-pump total current detection circuit and an integral control circuit of a circuit structure for implementing dual-pump laser current protection according to the present utility model.

Detailed Description

In order to more clearly describe the technical contents of the present utility model, a further description will be made below in connection with specific embodiments.

The circuit structure for realizing the double-pumping laser current protection comprises a first pumping circuit module, a second pumping circuit module, a third current sampling resistor, a third current sampling amplifying operation amplifier module and an integral amplifying operation amplifier module, wherein the circuit structures of the first pumping circuit module and the second pumping circuit module are the same, the output end of the first pumping circuit module and the output end of the second pumping circuit module are connected with the third current sampling resistor, one end of the third current sampling amplifying operation amplifier module is connected with the third current sampling resistor, the other end of the third current sampling amplifying operation amplifier module is connected with the integral amplifying operation amplifier module, and the other end of the integral amplifying operation amplifier module is connected with the variable resistor areas of the first pumping circuit module and the second pumping circuit module.

As the preferred implementation mode of the utility model, the first pumping circuit module comprises a bias resistor, a third MOS tube, a current adjusting operational amplifier module, a current sampling amplifying operational amplifier module, a DC-DC module, a pumping laser luminotron, a current sampling resistor and a first MOS tube,

the input end of the bias resistor is connected with the digital-analog converter at the front end, the drain electrode of the third MOS tube is connected with the bias resistor, the source electrode of the third MOS tube is grounded, the grid electrode of the third MOS tube of the first pumping circuit module is connected with the grid electrode of the third MOS tube of the second pumping circuit module, one end of the current regulation operational amplifier module is connected with the bias resistor and the drain electrode of the third MOS tube, the other end of the current regulation operational amplifier module is respectively connected with the current sampling amplification operational amplifier module and the DC-DC module, the other end of the DC-DC module is connected with the positive electrode of the pumping laser luminous tube, the negative electrode of the pumping laser luminous tube is connected with the current sampling resistor, the two ends of the output end of the current sampling amplification operational amplifier module are connected with the two ends of the current sampling resistor, the output end of the current sampling resistor is connected with the drain electrode of the first MOS tube, the source electrode of the first MOS tube is connected with the third current sampling resistor, and the grid electrode of the first MOS tube is connected with an external control signal.

As a preferred embodiment of the present utility model, the resistances of the current sampling resistors of the first pumping circuit module and the second pumping circuit module are the same.

As a preferred embodiment of the utility model, the circuit structure further comprises a power interface filter circuit, the power interface filter circuit comprises a current protection and overvoltage protection unit, an initial power supply port filter unit and a power supply state indication unit, the current protection and overvoltage protection unit comprises a fuse and a TVS tube, the initial power supply port filter unit comprises a common mode inductor and a plurality of capacitors, the power supply state indication unit comprises a sixth seventh resistor and a first light emitting diode, the fuse is connected with an input power supply, the TVS tube is connected with the fuse, the capacitors are connected in parallel with two ends of the common mode inductor, the seventh resistor is connected with the initial power supply port filter unit, and the first light emitting diode is connected in parallel with two ends of the initial power supply port filter unit.

As a preferred embodiment of the utility model, the circuit structure further comprises a power supply conversion circuit, the power supply conversion circuit comprises an LDO linear voltage stabilizer, a linear voltage stabilizer filtering unit and a voltage conversion functional unit, the linear voltage stabilizer filtering unit comprises a plurality of capacitors and magnetic beads, the capacitors are respectively connected with ports of the LDO linear voltage stabilizer, the magnetic beads are connected with the input end of the LDO linear voltage stabilizer, and the voltage conversion functional unit is connected with the LDO linear voltage stabilizer.

As a preferred embodiment of the utility model, the circuit structure further comprises a high-low power pumping switching circuit, wherein the high-low power pumping switching circuit comprises a PWM-DAC unit, an analog switch and an analog switch filtering decoupling unit, the output end of the PWM-DAC unit is connected with the analog switch, and the analog switch filtering decoupling unit is connected with the analog switch.

As a preferred embodiment of the utility model, the circuit structure further comprises a pumping current regulating circuit connected with the high-low power pumping switching circuit, wherein the pumping current regulating circuit comprises a DAC signal regulating unit and a closed-loop control unit, the DAC signal regulating unit is connected with the analog switch, and the closed-loop control unit is connected with the DAC signal regulating unit.

As a preferred embodiment of the present utility model, the circuit structure further includes a DC-DC output circuit, where the DC-DC output circuit includes a DC-DC chip, a DC-DC chip filtering decoupling unit, a fourth third sampling resistor, and a current-voltage conversion unit, where the DC-DC chip filtering decoupling unit and the fourth third sampling resistor are connected to the DC-DC chip, and where the current-voltage conversion unit is connected to the fourth third sampling resistor and the DC-DC chip.

As a preferred embodiment of the utility model, the circuit structure further comprises a single-path pumping current detection circuit connected with the DC-DC output circuit, wherein the single-path pumping current detection circuit comprises a pumping unit and a pumping switching control unit, the pumping unit is connected with the DC-DC output circuit, and the pumping switching control unit is connected with the pumping unit.

As a preferred embodiment of the present utility model, the circuit structure further includes a double-pump total current detection circuit and an integration control circuit, where the double-pump total current detection circuit and the integration control circuit include a fifth third current sampling resistor and a current-voltage conversion unit of the fifth third current sampling resistor, and further include a tenth operational amplifier and an output limiting unit of the tenth operational amplifier, where the output limiting unit of the tenth operational amplifier is connected with the current-voltage conversion unit of the fifth third current sampling resistor.

In the specific implementation mode of the utility model, the problem that the working circuit of the laser generator is turned off in time to enable no matter whether the laser generator generates over-power output due to software abnormality or hardware abnormality is solved.

Fig. 1 is a circuit architecture diagram. The circuit architecture diagram clearly shows the working principle of the utility model, the principle description being directly referred to the above-described technical solution.

Fig. 2 is an overall circuit of the dual pump laser current protection circuit. The circuit diagram is a set of other sub-circuit diagrams, and is a complete circuit diagram. Fig. 2 is represented in a block diagram, and fig. 1 can be understood as a professional illustration of fig. 2.

Fig. 3 is a power interface filter circuit. The circuit diagram is a circuit for limiting current, filtering and suppressing surge and overvoltage of a power interface.

Fig. 4 is a 3.3V power conversion circuit. The circuit diagram is a 5V to 3.3V power conversion circuit.

Fig. 5 is a high-low power pump switching circuit and pump current regulating circuit. The circuit diagram is a pumping current driving current DAC control enabling circuit, the circuit comprises a high power switching state and a low power switching state, and the pumping power switching needs to be fast due to the fact that a main control output DAC needs a certain time, so that the circuit realizes that DAC values of two pumping powers are prepared in advance, the analog switch is used for switching, and fast DAC value switching is realized. Meanwhile, the pumping current control circuit realizes the FB of the control DC-DC after the real output current feedback pin and the control DAC value are subjected to operational amplification processing, and realizes the pumping current control of a closed loop.

Fig. 6 is a DC-DC output circuit and a single pump current detection circuit. The circuit is a DC-DC converter for driving the pump, so that the high voltage of the DC-DC converter is reduced to the low voltage at which the pump can work, and the colleague controls the constant current working mode of the pump, so that the working output power of the pump becomes controllable. Meanwhile, the current detection circuit converts current into a voltage signal through a current sampling resistor connected in series, and then converts pumped working current into a corresponding voltage signal through the amplification function of an operational amplifier. And two further pumps for blocking the road.

Fig. 7 shows a double-pump total current detection circuit and an integral control circuit. The circuit realizes the operation of combining two independent pumps in a main circuit, and has the advantages that the two pumps are finally combined together through the same current sampling resistor, and the function of detecting the total current of the two pumps at one time is realized through the sampling resistor. The total current of the two pumps is further converted into voltage through the operational amplifier through the sampling resistor, so that the total current of the two pumps is converted into corresponding voltage signals, and the voltage signals are further converted into a variable resistance area of the control MOS tube through the integrating circuit, so that the function of closed loop current limiting through the total current of the two pumps is realized.

In the circuit, the output size of pumping current is controlled by the front-stage DAC, and meanwhile, the DAC finally outputs to the current regulating operational amplifier and is also subjected to the starting of the third MOS tube or the resistance voltage division generated when the third MOS tube is positioned in the variable resistance region.

The DCA value generated by the main control and the current sampling amplifying operational amplifier module control the FB feedback pin of the DC-DC under the dual action of the current adjusting operational amplifier module, so as to control the real output current of the pump.

The output energy of the pump is derived from the conversion of the DC-DC module. Meanwhile, the DC-DC output mode is a constant current mode, and constant current driving of the pumping laser luminotron is realized through the feedback effect of current.

The pumping current generates sampling voltage on the current sampling resistor, and the sampling voltage is fed back to the current sampling amplifying operational amplifier circuit to realize the signal conversion of current and voltage.

Whether the pump can normally output or not also depends on the starting state of the back-end MOS tube, the MOS tube is controlled by the main control, the pump can be started when the main control needs to output, and the pump can be closed when the main control needs to close the pump output.

The principle of operation of the other pump is identical to that described above, since it is in the double pump mode.

Since the final effect of the double pump operation is that the sum of the output power of the two pumps cannot exceed the fixed power output requirement, the two pumps can finally detect the total current through the same sampling resistor.

The current of the third current sampling resistor after the two paths of merging is converted into a voltage signal through a third current sampling amplifying operational amplifier module, the voltage signal is used for controlling a variable resistance area of a DAC output MOS tube at the forefront end of the variable resistance area through an integral amplifying operational amplifier to enable the variable resistance area to be supplied to a DAC value of a current adjusting operational amplifier to change, the change finally inhibits the total current of double pumping from exceeding a preset value, and the value can be smaller than pumping current corresponding to the DAC value output by a main control. The purpose of this is that the completely independent hardware circuit is overridden by the master control authority for pump current control. Thereby realizing the safety protection function of pumping current.

Further, the current limiting protection and overvoltage protection of the whole circuit are formed by the fuse F1 and the TVS tube TVS1 in fig. 3; the capacitors C131, C123, C133, C134, C135, C136, C137, C138, C139, C140, C141, C142 and the common-mode inductor L3 realize the filtering effect of the initial power supply port of the whole circuit; the power supply state indication is realized through the resistor R67 and the light emitting diode LED 1.

Further, the filtering effect on the LDO linear voltage regulator U12 is completed through the magnetic beads R68, the capacitors C128, C129, C130, C144, C145, C146, C147, C148 and C149 in FIG. 4; the 3.3V voltage conversion function configuration of U12 is realized through the capacitor C143 and the resistors R69 and R70.

Further, two paths of PWM signals are converted into DAC signals through the functions of resistors R1, R2, R3, R12, R13 and R6 capacitors C1, C2, C5, C7, C11 and C10 operational amplifier U1 in FIG. 5; further, only one path of DAC signal can be output at the same time under the action of the analog switch U5; the capacitors C3 and C4 are used for filtering and decoupling the U5 chip. Further, DAC signals output by the analog switch are further regulated under the action of resistors R4 and R7 and a MOS tube M1; closed loop control of current and power of DC-DC is realized under the action of resistors R8, R11, R14, R5, R9, R10, capacitors C6, C9, C8 and operational amplifier U6.

Further, the DC-DC chip U9 is filtered and decoupled by capacitors C28, C29, C30, C31, C32, C33, C34, C35, C36, C37, C38, C39, C40, C41, C42, C43, C44, C45, C46, C47, C48, C49, C50, C51, C52, C53, C55, C56, C57, C58, C59, C60, C61, C62, C63, C64, C65, C66, C67, C68, C69, C70, C71, C72, C73 inside fig. 6; the capacitor C27 and the inductor L1 are functional devices for U9; the resistor R43 is a sampling resistor; the resistors R38, R39, R36, R32, R34, R31, R30, R33, the capacitors C25, C24 and the op-amp U4 realize the conversion of the current signal to the voltage signal of the sampling resistor R43. The LD1 is further pumped to realize the power output of laser; the resistors R50 and R48, the MOS tube M3 and the MOS tube Q1 realize the on and off control of the pump LD 1.

Further, the function of the resistor R53 in fig. 7 as a current sampling resistor, resistors R51, R52, R47, R40, R45, R42, R37, R44, R41, R35, capacitors C77, C76, C74, C75, C26, the op-amp U20, and the op-amp U10 realizes the conversion of the current signal of the sampling resistor R53 into a voltage signal, and the hardware forced output limitation of the closed loop on the total current of the dual pumps is realized through the integration function of the op-amp U10.

The working flow of the circuit of the utility model is as follows:

step 1: the master outputs a current DAC signal.

Any form of control signal, either PWM or DAC mode, enables control of the pump current, i.e. pump power.

Step 2: the pump current samples are fed back to the op-amp.

The pumping current is fed back to the operational amplifier after being sampled, so that the conversion from the pumping current signal to the voltage signal is realized.

Step 3: the DC-DC output current is closed loop controlled.

The FB pin of the DC-DC is controlled through the action of the operational amplifier circuit, so that the closed-loop control of pumping current output is further realized. The closed-loop control mode of outputting the PWM or DAC as the original power output electric signal to the final pump to output the specified power is realized.

Step 4: and the double-pump total current is collected and fed back.

The final loop of the double pumping work is through the same sampling resistor, so that the total working current of the double pumping can be detected through the final same sampling resistor, and the sampling resistor realizes the conversion from the total current of the double pumping to the corresponding voltage signal through the operational amplifier.

Step 5: integrating feedback current-limiting double-pump total current.

And finally, outputting the voltage signal converted by the total current of the double pumps to an integrating circuit, wherein the circuit is matched with the MOS tube at the front section to further regulate the PWM or DAC signal output by the main control of the MOS tube, and the MOS tube is positioned in a variable resistance area only under the condition that the double pumps are output to a preset maximum current value, so that the PWM or DAC signal sent by the main control is further changed, and the final pump output power of the circuit is limited in a set power range and cannot be influenced by main control failure and the like. Is a separate total power detection circuit in the laser driver circuit and can control the driver circuit in a closed loop not to exceed a preset power threshold.

The specific implementation manner of this embodiment may be referred to the related description in the foregoing embodiment, which is not repeated herein.

It is to be understood that the same or similar parts in the above embodiments may be referred to each other, and that in some embodiments, the same or similar parts in other embodiments may be referred to.

It should be noted that in the description of the present utility model, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Furthermore, in the description of the present utility model, unless otherwise indicated, the meaning of "plurality" means at least two.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present utility model. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

By adopting the circuit structure for realizing the current protection of the double-pump laser, the double pumps can output high-power laser without pumping with high power, and meanwhile, the problem of too short service life of the laser caused by pumping loss and aging is avoided. When a single pump fails, another pump can work, so that the phenomenon that the laser module fails directly and cannot work is avoided. The reliability and low failure property of the laser module are improved. The double pumps can realize the interval switching work and the extension of the service life of the pump body, and finally the whole service life of the laser module is prolonged. Each of the two pumps has an independent current detection, and the value of the current detection can be fed back to the main control. The total current of the double pumping current is provided with an independent current detection functional unit, so that the double pumping total current can still be detected under the condition of double pumping failure; and further the control of the double-pump total current output at a fixed value is suppressed by the feedback function. The current protection circuit can still inhibit the total current output of double pumps on the premise of master control failure, and realizes the hardware limiting function of pumping current; the current protection circuit can still feed back to the main control under the premise that one path of the double-pump circuit fails, and can still continue to work under the premise that the other path of the double-pump circuit fails. The power of the laser generator is completely controllable, and the power output of the laser generator can still be ensured not to exceed a set value on the premise of device failure or main control failure, so that the laser output power is limited at a fixed value, and laser receiving equipment or objects can not be burnt or damaged. Thereby realizing the dual laser generation protection function.

In this specification, the utility model has been described with reference to specific embodiments thereof. It will be apparent, however, that various modifications and changes may be made without departing from the spirit and scope of the utility model. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.

Claims (10)

1. The circuit structure is characterized by comprising a first pumping circuit module, a second pumping circuit module, a third current sampling resistor, a third current sampling amplifying operation amplifying module and an integral amplifying operation amplifying module, wherein the circuit structures of the first pumping circuit module and the second pumping circuit module are the same, the output end of the first pumping circuit module and the output end of the second pumping circuit module are connected with the third current sampling resistor, one end of the third current sampling amplifying operation amplifying module is connected with the third current sampling resistor, the other end of the third current sampling amplifying operation amplifying module is connected with the integral amplifying operation amplifying module, and the other end of the integral amplifying operation amplifying module is connected with the variable resistor areas of the first pumping circuit module and the second pumping circuit module.

2. The circuit structure for realizing the current protection of the double-pumping laser according to claim 1, wherein the first pumping circuit module comprises a bias resistor, a third MOS tube, a current adjusting operational amplifier module, a current sampling amplifying operational amplifier module, a DC-DC module, a pumping laser luminous tube, a current sampling resistor and a first MOS tube,

the input end of the bias resistor is connected with the digital-analog converter at the front end, the drain electrode of the third MOS tube is connected with the bias resistor, the source electrode of the third MOS tube is grounded, the grid electrode of the third MOS tube of the first pumping circuit module is connected with the grid electrode of the third MOS tube of the second pumping circuit module, one end of the current regulation operational amplifier module is connected with the bias resistor and the drain electrode of the third MOS tube, the other end of the current regulation operational amplifier module is respectively connected with the current sampling amplification operational amplifier module and the DC-DC module, the other end of the DC-DC module is connected with the positive electrode of the pumping laser luminous tube, the negative electrode of the pumping laser luminous tube is connected with the current sampling resistor, the two ends of the output end of the current sampling amplification operational amplifier module are connected with the two ends of the current sampling resistor, the output end of the current sampling resistor is connected with the drain electrode of the first MOS tube, the source electrode of the first MOS tube is connected with the third current sampling resistor, and the grid electrode of the first MOS tube is connected with an external control signal.

3. The circuit structure for realizing current protection of double pumping laser according to claim 1, wherein the resistances of the current sampling resistors of the first pumping circuit module and the second pumping circuit module are the same.

4. The circuit structure for realizing the current protection of the double-pump laser according to claim 1, further comprising a power interface filter circuit, wherein the power interface filter circuit comprises a current protection and overvoltage protection unit, an initial power supply port filter unit and a power supply state indication unit, the current protection and overvoltage protection unit comprises a fuse and a TVS tube, the initial power supply port filter unit comprises a common mode inductor and a plurality of capacitors, the power supply state indication unit comprises a sixth seventh resistor and a first light emitting diode, the fuse is connected with an input power supply, the TVS tube is connected with the fuse, the capacitors are connected with two ends of the common mode inductor in parallel, the sixth seventh resistor is connected with the initial power supply port filter unit, and the first light emitting diode is connected with two ends of the initial power supply port filter unit in parallel.

5. The circuit structure for realizing the current protection of the double-pump laser according to claim 1, further comprising a power supply conversion circuit, wherein the power supply conversion circuit comprises an LDO linear voltage stabilizer, a linear voltage stabilizer filtering unit and a voltage conversion functional unit, the linear voltage stabilizer filtering unit comprises a plurality of capacitors and magnetic beads, the capacitors are respectively connected with ports of the LDO linear voltage stabilizer, the magnetic beads are connected with an input end of the LDO linear voltage stabilizer, and the voltage conversion functional unit is connected with the LDO linear voltage stabilizer.

6. The circuit structure for realizing the current protection of the double-pump laser according to claim 1, further comprising a high-low power pump switching circuit, wherein the high-low power pump switching circuit comprises a PWM-DAC unit, an analog switch and an analog switch filtering decoupling unit, the output end of the PWM-DAC unit is connected with the analog switch, and the analog switch filtering decoupling unit is connected with the analog switch.

7. The circuit structure for realizing the current protection of the double-pumping laser according to claim 6, further comprising a pumping current regulating circuit connected with the high-low power pumping switching circuit, wherein the pumping current regulating circuit comprises a DAC signal regulating unit and a closed-loop control unit, the DAC signal regulating unit is connected with the analog switch, and the closed-loop control unit is connected with the DAC signal regulating unit.

8. The circuit structure for realizing the current protection of the double-pump laser according to claim 1, further comprising a DC-DC output circuit, wherein the DC-DC output circuit comprises a DC-DC chip, a DC-DC chip filtering decoupling unit, a fourth three sampling resistor and a current-voltage conversion unit, the DC-DC chip filtering decoupling unit and the fourth three sampling resistor are connected with the DC-DC chip, and the current-voltage conversion unit is connected with the fourth three sampling resistor and the DC-DC chip.

9. The circuit structure for realizing the current protection of the double-pump laser according to claim 8, further comprising a single-path pumping current detection circuit connected with the DC-DC output circuit, wherein the single-path pumping current detection circuit comprises a pumping unit and a pumping switching control unit, the pumping unit is connected with the DC-DC output circuit, and the pumping switching control unit is connected with the pumping unit.

10. The circuit structure for realizing the current protection of the double-pumping laser according to claim 1, further comprising a double-pumping total current detection circuit and an integral control circuit, wherein the double-pumping total current detection circuit and the integral control circuit comprise a fifth third current sampling resistor and a current-voltage conversion unit of the fifth third current sampling resistor, and further comprise a tenth operational amplifier and an output limiting unit of the tenth operational amplifier, and the output limiting unit of the tenth operational amplifier is connected with the current-voltage conversion unit of the fifth third current sampling resistor.