CN220341673U - Tunable laser and PZT driving circuit thereof - Google Patents

Abstract

The utility model discloses a tunable laser and a PZT driving circuit thereof, wherein the PZT driving circuit of the tunable laser comprises: the first power supply circuit comprises a first power supply signal input end and a first power supply output end; the first power supply signal input end is electrically connected with a power supply; the second power supply circuit comprises a second power supply signal input end and a second power supply output end; the second power supply signal input end is electrically connected with the power supply; the filter circuit comprises a driving signal input end, a second power end and a filter signal output end; the driving signal input end is electrically connected with the driving signal output end of the controller, and the second power supply end is electrically connected with the second power supply output end; the amplifying circuit comprises a filtering signal input end, a first power end and an amplifying signal output end; the filter signal input end is electrically connected with the filter signal output end, the amplified signal output end is electrically connected with the control end of the PZT load, and the first power supply end is electrically connected with the first power supply output end. The technical scheme can improve the driving quality of the PZT load.

Description

Tunable laser and PZT driving circuit thereof

Technical Field

The utility model relates to the technical field of piezoelectric ceramic driving circuits, in particular to a tunable laser and a PZT driving circuit thereof.

Background

One of the tuning modes of the tunable laser is: by applying different voltage signals to the piezo-ceramic (Piezoelectric Transducer, PZT) load, the PZT load is deformed, thereby changing the distance of the grating in the laser to adjust the wavelength of the laser light passing through the grating. Wherein, the voltage signals applied to the PZT are different, and the laser can realize modulation of different wavelengths.

At present, a controller is adopted to provide a driving signal for a PZT load, but the driving signal comprises interference signals such as noise, and when the driving signal is applied to the PZT load, the deformation of the PZT load can be influenced, so that the modulation effect of a grating on the laser wavelength is influenced.

Disclosure of Invention

The utility model provides a tunable laser and a PZT driving circuit thereof, which are used for filtering interference signals such as high-frequency noise and the like in driving signals and improving the quality of the driving signals.

In a first aspect, the present utility model provides a PZT driving circuit for a tunable laser, comprising:

the first power supply circuit comprises a first power supply signal input end and a first power supply output end; the first power supply signal input end is electrically connected with a power supply;

the second power supply circuit comprises a second power supply signal input end and a second power supply output end; the second power supply signal input end is electrically connected with the power supply;

the filter circuit comprises a driving signal input end, a second power end and a filter signal output end; the driving signal input end is electrically connected with the driving signal output end of the controller, and the second power supply end is electrically connected with the second power supply output end;

the amplifying circuit comprises a filtering signal input end, a first power end and an amplifying signal output end; the filter signal input end is electrically connected with the filter signal output end, the amplified signal output end is electrically connected with the control end of the PZT load, and the first power supply end is electrically connected with the first power supply output end.

Optionally, the filter circuit includes an eighth order butterworth filter.

Optionally, the amplifying circuit further includes a first operational amplifier, a first variable resistor and a first capacitor;

the non-inverting input end of the first operational amplifier is electrically connected with the filtering signal input end, the inverting input end of the first operational amplifier is electrically connected with the first end of the first variable resistor and the first end of the first capacitor, the second end of the first variable resistor and the second end of the first capacitor are electrically connected with the output end of the first operational amplifier, the output end of the first operational amplifier is electrically connected with the amplifying signal output end, the power end of the first operational amplifier is electrically connected with the first power end, and the grounding end of the first operational amplifier is grounded.

Optionally, the amplifying circuit further includes a second capacitor;

the first end of the second capacitor is electrically connected with the power end of the first operational amplifier, and the second end of the second capacitor is grounded.

Optionally, the amplifying circuit further comprises a first filter circuit and a second filter circuit;

the first filter circuit comprises a first filter resistor and a first filter capacitor; the first end of the first filter resistor is electrically connected with the filter signal input end, the second end of the first filter resistor is electrically connected with the in-phase input end, the first end of the first filter capacitor is electrically connected with the filter signal input end, and the second end of the first filter capacitor is grounded;

the second filter circuit comprises a second filter resistor and a second filter capacitor; the first end of the second filter resistor is electrically connected with the output end of the first operational amplifier, the second end of the second filter resistor is electrically connected with the filter signal output end, the first end of the second filter capacitor is electrically connected with the filter signal output end, and the second end of the second filter capacitor is grounded.

Optionally, the first power supply circuit includes a first power supply chip, a third capacitor, a first resistor and a second variable resistor;

the first power chip comprises a first input pin, a first turn-off pin, a first output pin and a first adjustable voltage pin;

the first input pin and the first turn-off pin are electrically connected with the first power signal input end;

the first output pin is electrically connected with the first ends of the third capacitor and the second variable resistor respectively, and the first adjustable voltage pin is electrically connected with the second end of the third capacitor; the first adjustable voltage pin is electrically connected with a first end of the first resistor and an adjusting end of the second variable resistor, and a second end of the first resistor is grounded; the second end of the second variable resistor is arranged in a floating mode.

Optionally, the first power supply circuit further includes a fourth capacitor;

the first end of the fourth capacitor is electrically connected with the first output pin, and the second end of the fourth capacitor is grounded.

Optionally, the second power supply circuit includes a second power supply chip, a fifth capacitor, a second resistor and a third resistor;

the second power chip comprises a second input pin, a second turn-off pin, a second output pin and a second adjustable voltage pin;

the second input pin and the second turn-off pin are respectively and electrically connected with the second power signal input end;

the second output pin is electrically connected with the first ends of the fifth capacitor and the third resistor respectively, and the second adjustable voltage pin is electrically connected with the second end of the fifth capacitor; the second adjustable voltage pin is electrically connected with the first end of the second resistor and the second end of the third resistor, and the second end of the second resistor is grounded.

Optionally, the second power supply circuit further includes a sixth capacitor;

the first end of the sixth capacitor is electrically connected with the second output pin, and the second end of the sixth capacitor is grounded.

In a second aspect, the present utility model also provides a tunable laser comprising: a laser body and a PZT driving circuit of the tunable laser of the first aspect;

the laser body includes at least a PZT load; a PZT drive circuit of the tunable laser is electrically connected to the PZT load.

According to the technical scheme, the second power supply required by work is provided for the filter circuit through the second power supply, the first power supply required by work is provided for the amplifying circuit through the first power supply, stable power signals are provided for the filter circuit and the amplifying circuit, the fact that fluctuation of the power signals affects the filtering and amplifying effects of the filter circuit and the amplifying circuit is prevented, the driving signals are amplified through the filter circuit, only required signals in the driving signals can be reserved, after the filtering signals are amplified through the amplifying circuit, amplified signals required by the PZT load can be obtained, the PZT load is prevented from receiving driving signals with interference signals, and the driving quality of the PZT load is improved.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions of the prior art, a brief description will be given below of the drawings required for the embodiments or the description of the prior art, and it is obvious that although the drawings in the following description are specific embodiments of the present utility model, it is obvious to those skilled in the art that the basic concepts of the device structure, the driving method and the manufacturing method, which are disclosed and suggested according to the various embodiments of the present utility model, are extended and extended to other structures and drawings, and it is needless to say that these should be within the scope of the claims of the present utility model.

FIG. 1 is a schematic diagram of a PZT driving circuit for a tunable laser according to an embodiment of the present utility model;

fig. 2 is a schematic circuit diagram of a filtering circuit according to an embodiment of the present utility model;

fig. 3 is a schematic circuit diagram of an amplifying circuit according to an embodiment of the present utility model;

FIG. 4 is a schematic diagram of another amplifying circuit according to an embodiment of the present utility model;

fig. 5 is a schematic structural diagram of a first power supply circuit according to an embodiment of the present utility model;

fig. 6 is a schematic structural diagram of a second power supply circuit according to an embodiment of the present utility model.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present utility model more apparent, the technical solutions of the present utility model will be clearly and completely described by means of implementation examples with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are some embodiments of the present utility model, not all embodiments. All other embodiments obtained by those skilled in the art based on the basic concepts disclosed and suggested by the embodiments of the present utility model are within the scope of the present utility model.

Fig. 1 is a schematic structural diagram of a PZT driving circuit of a tunable laser according to an embodiment of the present utility model, where, as shown in fig. 1, the PZT driving circuit of the tunable laser includes: the first power supply circuit 10 includes a first power supply signal input terminal in1 and a first power supply output terminal out1; the first power supply signal input end in1 is electrically connected with the power supply 1; the second power supply circuit 20 includes a second power supply signal input terminal in2 and a second power supply output terminal out2; the second power supply signal input end in2 is electrically connected with the power supply 1; the filter circuit 30 includes a driving signal input terminal P1, a second power supply terminal VCC2, and a filtered signal output terminal P2; the driving signal input end P1 is electrically connected with the driving signal output end P0 of the controller 01, and the second power supply end VCC2 is electrically connected with the second power supply output end out2; an amplifying circuit 40 including a filtered signal input terminal P3, a first power supply terminal VCC1, and an amplified signal output terminal P4; the filtered signal input terminal P3 is electrically connected to the filtered signal output terminal P2, the amplified signal output terminal P4 is electrically connected to the control terminal CON of the PZT load 50, and the first power supply terminal VCC1 is electrically connected to the first power supply output terminal out 1.

The power supply 1 may provide power signals to the first power supply circuit 10 and the second power supply circuit 20, so that the first power supply circuit 10 and the second power supply circuit 20 are in a working state, and the power signals may be electrical signals with high level or low level, and may be set according to actual needs, which is not limited herein specifically.

Specifically, after the second power circuit 20 performs voltage stabilization and/or voltage conversion on the power signal provided by the power supply 1, the second power signal is output to the second power terminal VCC2 of the filter circuit 30, so as to supply power to the filter circuit 30, so that the filter circuit 30 is in a working state, and a filtering effect is achieved; the first power circuit 20 performs voltage stabilization and/or voltage conversion and other processes on the power signal of the power supply 1 and outputs the first power signal to the first power end VCC1 of the amplifying circuit 40 so as to provide the power signal required by the operation for the amplifying circuit 40, and the amplifying circuit 40 is in an operating state to realize the amplifying effect; when the PZT load 50 needs to be driven, the controller 01 may output a driving signal to the filter circuit 30 according to the requirement of the PZT load 50, and the waveform of the driving signal may be a sine wave, a triangular wave, or the like, and may be set according to the actual requirement, which is not particularly limited herein. The driving signal output by the controller 01 is transmitted to the filter circuit 30 through the driving signal output end P0 and the driving signal input end P1, the filter circuit 30 filters the driving signal, only allows signals in a certain frequency range to normally pass, prevents signals outside the frequency range from passing, retains alternating current components in direct current voltage which possibly reduces pulsation, reduces the ripple coefficient of the output voltage, improves the flatness of the output filter signal, the filter signal is transmitted to the amplifying circuit 40 through the filter signal output end P2 and the filter signal input end P3, and the amplifying circuit 40 amplifies the input filter signal to the amplitude required by the PZT load 50 and the like to drive the PZT load 50.

According to the technical scheme, the second power supply required by work is provided for the filter circuit through the second power supply, the first power supply required by work is provided for the amplifying circuit through the first power supply, stable power signals are provided for the filter circuit and the amplifying circuit, the fact that fluctuation of the power signals affects the filtering and amplifying effects of the filter circuit and the amplifying circuit is prevented, the driving signals are amplified through the filter circuit, only required signals in the driving signals can be reserved, after the filtering signals are amplified through the amplifying circuit, amplified signals required by the PZT load can be obtained, the PZT load is prevented from receiving driving signals with interference signals, and the driving quality of the PZT load is improved.

In an alternative embodiment, fig. 2 is a schematic circuit diagram of a filtering circuit according to an embodiment of the present utility model, and as shown in fig. 2, the filtering circuit 30 includes an eighth order butterworth filter. The characteristics of the Butterworth filter are that the frequency response curve in the passband is flat to the maximum extent, no ripple exists, the band is gradually reduced to zero in the impedance band, the higher the order of the Butterworth filter is, the higher the amplitude attenuation speed of the band is, the attenuation rate of the eight-order Butterworth filter is 48 dB per frequency multiplication, the flatter signal can be output, the noise outside the passband is filtered to a great extent, the interference of the noise on the PZT load is reduced, and the driving quality of the PZT load is improved.

It can be understood that the eighth-order butterworth filter includes a plurality of resistors, capacitors, operational amplifiers and other devices, the parameters of each device in the eighth-order butterworth filter are changed, the parameters of the cut-off frequency and other parameters of the filter can be changed, the specific values of each device can be set according to actual needs, and the specific limitation is not made here. Illustratively, the eighth order butterworth filter may filter out noise above 25khz when the parameter values of the respective devices are as shown in fig. 2.

In an alternative embodiment, fig. 3 is a schematic circuit diagram of an amplifying circuit according to an embodiment of the present utility model, and as shown in fig. 3, the amplifying circuit 40 further includes a first operational amplifier T1, a first variable resistor R1', and a first capacitor C1; the non-inverting input end A1 of the first operational amplifier T1 is electrically connected with the filtering signal input end P3, the inverting input end A2 of the first operational amplifier T1 is electrically connected with the first end of the first variable resistor R1 'and the first end of the first capacitor C1, the second end of the first variable resistor R1' and the second end of the first capacitor C1 are electrically connected with the output end A3 of the first operational amplifier T1, the output end A3 of the first operational amplifier T1 is electrically connected with the amplified signal output end P4, the power end of the first operational amplifier T1 is electrically connected with the first power end VCC1, and the grounding end of the first operational amplifier T1 is grounded.

Specifically, the first operational amplifier T1, the first variable resistor R1' and the first capacitor C1 form a low-frequency amplifying circuit, the gain adjustment condition is related to the values of the first variable resistor R1' and the first capacitor C1, the first variable resistor R1' can stabilize the working point of the first operational amplifier T1, the first operational amplifier T1 is prevented from being turned off or saturated on, different amplifying gains are realized by changing the resistance value of the first variable resistor R1', that is, different amplifying signals are output, and the resistance value of the first variable resistor R1' can be reversely adjusted according to the electric signal required by the PZT load 50. The PZT load 50 itself is capacitive, the amplified signal directly drives the PZT load 50 to easily cause the self-oscillation of the first operational amplifier T1, the first variable resistor R1' and the first capacitor C1 form a negative feedback circuit with a certain frequency characteristic, and the first capacitor C1 can stably feedback interference fluctuation of oscillation caused in the current, thereby eliminating the oscillation problem and improving the output stability of the amplified signal.

It is to be understood that the parameter values of the first variable resistor R1' and the first capacitor C1 may be set according to actual needs, which is not specifically limited herein. The resistance of the first variable resistor R1' is 100kΩ, and the capacitance of the first capacitor C1 is 1 μf.

Optionally, referring to fig. 3, the amplifying circuit 40 further includes a second capacitor C2; the first end of the second capacitor C2 is electrically connected to the power supply end of the first operational amplifier T1, and the second end of the second capacitor C2 is grounded. The second capacitor C2 may be a chip capacitor or the like. The second capacitor C2 can enable high-frequency noise in the power supply signal to flow into the ground terminal through the second capacitor C2, so that the high-frequency noise is prevented from entering the first operational amplifier T1, normal operation of the first operational amplifier T1 is interfered, and the first operational amplifier T1 is enabled to work stably. The capacitance value of the second capacitor C2 may be set according to actual needs, and is not specifically limited herein. The capacitance value of the second capacitance C2 is, for example, 0.1 μf.

Optionally, fig. 4 is a schematic circuit diagram of another amplifying circuit according to an embodiment of the present utility model, and as shown in fig. 4, the amplifying circuit 40 further includes a first filtering circuit 41 and a second filtering circuit 42; the first filter circuit 41 includes a first filter resistor R4 and a first filter capacitor C7; the first end of the first filter resistor R4 is electrically connected with the filter signal input end P3, the second end of the first filter resistor R4 is electrically connected with the in-phase input end A1, the first end of the first filter capacitor C7 is electrically connected with the filter signal input end P3, and the second end of the first filter capacitor C7 is grounded; the second filter circuit 42 includes a second filter resistor R5 and a second filter capacitor C8; the first end of the second filter resistor R5 is electrically connected with the output end of the first operational amplifier T1, the second end of the second filter resistor R5 is electrically connected with the filter signal output end P2, the first end of the second filter capacitor C8 is electrically connected with the filter signal output end P2, and the second end of the second filter capacitor C8 is grounded.

Specifically, the first filter capacitor C7 in the first filter circuit 41 and the second filter capacitor C8 in the second filter circuit 42 are electrically connected with the ground terminal, and since the capacitors have the characteristic of blocking direct current by alternating current, the high-frequency electric signal is discharged to the ground terminal through the filter capacitors, so that the first filter circuit 41 and the second filter circuit 42 are both first-order low-pass filter circuits, can filter the alternating current signal in the input signal, retain the direct current signal, and have simple circuit composition and strong anti-interference capability.

It will be appreciated that the cut-off frequency of the first filter circuit 41 is related to the parameter values of the first filter resistor R4 and the first filter capacitor C7, and the cut-off frequency of the second filter circuit 42 is related to the parameter values of the second filter resistor R5 and the second filter capacitor C8, which may be set according to practical needs, and is not limited herein specifically. In an exemplary embodiment, the parameter values of the first filter resistor R4, the first filter capacitor C7, the second filter resistor R5, and the second filter capacitor C8 are 10kΩ, 10μf, 49.9kΩ, 10μf, respectively.

In an alternative embodiment, fig. 5 is a schematic structural diagram of a first power supply circuit according to an embodiment of the present utility model, and as shown in fig. 5, the first power supply circuit 10 includes a first power supply chip 11, a third capacitor C3, a first resistor R1 and a second variable resistor R2'; the first power chip 11 includes a first input pin IN1, a first shutdown pin SHDN1, a first output pin OUT1, and a first adjustable voltage pin ADJ1; the first input pin IN1 and the first shutdown pin SHDN1 are electrically connected with the first power supply signal input end IN 1; the first output pin OUT1 is electrically connected with a first end of the third capacitor C3 and a first end of the second variable resistor R2', and the first adjustable voltage pin ADJ1 is electrically connected with a second end of the third capacitor C3; the first adjustable voltage pin ADJ1 is electrically connected with the first end of the first resistor R1 and the adjusting end of the second variable resistor R2', and the second end of the first resistor R1 is grounded; the second end of the second variable resistor R2' is arranged in a floating manner.

Wherein the first power supply circuit 10 is configured to provide a stable first power supply signal to the amplifying circuit 20. The first power supply chip 11 may be a voltage stabilizing chip such as a low dropout linear voltage stabilizer, where the low dropout linear voltage stabilizer is a micro system with very low consumption, integrates a hardware circuit such as a MOS transistor, a schottky diode, a voltage dividing resistor, and the like with very low on-line on-resistance, and has functions of over-current protection, over-temperature protection, a precise reference source, a differential amplifier, a retarder, and the like, and has very low self-noise, a high power supply rejection ratio, and stable output power.

For example, the first power chip 11 has a model LT3066, an input voltage range of 1.6V-45V, an output voltage range of 0.6V-19V, and when the potential of the first shutdown pin SHDN1 is at a high level, the LT3066 is enabled to operate, and when the potential of the first shutdown pin SHDN1 is at a low level, the LT3066 performs active discharge. After high-level electric signals are input to the first input pin IN1 and the first shutdown pin SHDN1, the electric signals are output to the first output pin OUT1 through an internal device of LT3066, different voltages can be output to the first output pin OUT1 through adjusting the resistance value of the second variable resistor R2', and the resistance value of the second variable resistor R2' can be adjusted through the first adjustable voltage pin ADJ1 according to the power signal requirement of the power supply end of the amplifying circuit 40 so as to generate a stable first power signal.

Optionally, referring to fig. 5, the first power supply circuit 10 further includes a fourth capacitor C4; the first end of the fourth capacitor C4 is electrically connected to the first output pin OUT1, and the second end of the fourth capacitor C4 is grounded. The fourth capacitor C4 may be a ceramic chip capacitor, etc., where the fourth capacitor C4 may further filter out high frequency noise in the first power signal, so as to prevent the high frequency noise from entering the post-stage circuit and interfering with the normal operation of the post-stage circuit. The capacitance value of the fourth capacitor C4 may be set according to actual needs, and is not particularly limited herein. The fourth capacitance C4 has a capacitance value of 10 muf, for example.

In an alternative embodiment, fig. 6 is a schematic structural diagram of a second power supply circuit according to an embodiment of the present utility model, and as shown in fig. 6, the second power supply circuit 20 includes a second power supply chip 21, a fifth capacitor C5, a second resistor R2 and a third resistor R3; the second power chip 21 includes a second input pin IN2, a second shutdown pin SHDN2, a second output pin OUT2, and a second adjustable voltage pin ADJ2; the second input pin IN2 and the second shutdown pin SHDN2 are respectively and electrically connected with the second power supply signal input end IN 2; the second output pin OUT2 is electrically connected with the first end of the fifth capacitor C5 and the first end of the third resistor R3 respectively, and the second adjustable voltage pin ADJ2 is electrically connected with the second end of the fifth capacitor C5; the second adjustable voltage pin ADJ2 is electrically connected to the first end of the second resistor R2 and the second end of the third resistor R3, and the second end of the second resistor R2 is grounded.

Wherein the second power supply circuit 20 is configured to provide a stable second power supply signal to the filter circuit 30. The second power supply chip 21 may be a voltage stabilizing chip such as a low dropout linear voltage stabilizer, where the low dropout linear voltage stabilizer is a micro system with very low consumption, integrates a hardware circuit such as a MOS transistor, a schottky diode, a voltage dividing resistor, and the like with very low on-line on-resistance, and has functions of over-current protection, over-temperature protection, a precise reference source, a differential amplifier, a retarder, and the like, and has very low self-noise, high power supply rejection ratio, and stable output power.

For example, the second power chip 21 has a model LT3066, an input voltage range of 1.6V-45V, an output voltage range of 0.6V-19V, and when the potential of the second shutdown pin SHDN2 is at a high level, the LT3066 is enabled to operate, and when the potential of the second shutdown pin SHDN2 is at a low level, the LT3066 performs active discharge. After the high-level electric signals are input to the second input pin IN1 and the first shutdown pin SHDN2, the electric signals are output to the first output pin OUT1 through the internal device of LT3066, the first output pin OUT1 can output fixed voltage by setting the resistance value of the third resistor R3, the resistance value of the third resistor R3 can be set IN advance according to the power signal requirement of the power supply end of the filter circuit 30, and a stable second power signal is generated through the voltage division among the fifth capacitor C5, the second resistor R2 and the third resistor R3.

Optionally, referring to fig. 6, the second power supply circuit 20 further includes a sixth capacitor C6; the first end of the sixth capacitor C6 is electrically connected to the second output pin OUT2, and the second end of the sixth capacitor C6 is grounded. The sixth capacitor C6 may be a ceramic chip capacitor, etc., where the sixth capacitor C6 may further filter out high frequency noise in the second power signal, so as to prevent the high frequency noise from entering the post-stage circuit and interfering with the normal operation of the post-stage circuit. The capacitance value of the sixth capacitor C6 may be set according to actual needs, and is not particularly limited herein. Illustratively, the sixth capacitance C6 has a capacitance value of 10 μF.

Based on the same inventive concept, an embodiment of the present utility model also provides a tunable laser including: a laser body and a PZT driving circuit for a tunable laser provided by any of the embodiments of the present utility model; the laser body includes at least a PZT load; the PZT drive circuit of the tunable laser is electrically connected to the PZT load. In this way, the amplified signal output by the PZT driving circuit of the tunable laser can be transmitted to the PZT load, and the grating in the laser body is changed by changing the deformation degree of the PZT load, so that the tunable laser wavelength is realized.

Note that the above is only a preferred embodiment of the present utility model and the technical principle applied. It will be understood by those skilled in the art that the present utility model is not limited to the particular embodiments described herein, and that various obvious changes, rearrangements, combinations, and substitutions can be made by those skilled in the art without departing from the scope of the utility model. Therefore, while the utility model has been described in connection with the above embodiments, the utility model is not limited to the embodiments, but may be embodied in many other equivalent forms without departing from the spirit or scope of the utility model, which is set forth in the following claims.

Claims (10)

1. A PZT driving circuit for a tunable laser, comprising:

the first power supply circuit comprises a first power supply signal input end and a first power supply output end; the first power supply signal input end is electrically connected with a power supply;

the second power supply circuit comprises a second power supply signal input end and a second power supply output end; the second power supply signal input end is electrically connected with the power supply;

the filter circuit comprises a driving signal input end, a second power end and a filter signal output end; the driving signal input end is electrically connected with the driving signal output end of the controller, and the second power supply end is electrically connected with the second power supply output end;

the amplifying circuit comprises a filtering signal input end, a first power end and an amplifying signal output end; the filter signal input end is electrically connected with the filter signal output end, the amplified signal output end is electrically connected with the control end of the PZT load, and the first power supply end is electrically connected with the first power supply output end.

2. The PZT driving circuit for a tunable laser according to claim 1, wherein the filter circuit includes an eighth order butterworth filter.

3. The PZT driving circuit for a tunable laser of claim 1, wherein said amplifying circuit further comprises a first operational amplifier, a first variable resistor, and a first capacitor;

the non-inverting input end of the first operational amplifier is electrically connected with the filtering signal input end, the inverting input end of the first operational amplifier is electrically connected with the first end of the first variable resistor and the first end of the first capacitor, the second end of the first variable resistor and the second end of the first capacitor are electrically connected with the output end of the first operational amplifier, the output end of the first operational amplifier is electrically connected with the amplifying signal output end, the power end of the first operational amplifier is electrically connected with the first power end, and the grounding end of the first operational amplifier is grounded.

4. The PZT driving circuit for a tunable laser of claim 3, wherein said amplifying circuit further comprises a second capacitor;

the first end of the second capacitor is electrically connected with the power end of the first operational amplifier, and the second end of the second capacitor is grounded.

5. The PZT driving circuit for a tunable laser according to claim 3, wherein the amplifying circuit further includes a first filter circuit and a second filter circuit;

the first filter circuit comprises a first filter resistor and a first filter capacitor; the first end of the first filter resistor is electrically connected with the filter signal input end, the second end of the first filter resistor is electrically connected with the in-phase input end, the first end of the first filter capacitor is electrically connected with the filter signal input end, and the second end of the first filter capacitor is grounded;

the second filter circuit comprises a second filter resistor and a second filter capacitor; the first end of the second filter resistor is electrically connected with the output end of the first operational amplifier, the second end of the second filter resistor is electrically connected with the filter signal output end, the first end of the second filter capacitor is electrically connected with the filter signal output end, and the second end of the second filter capacitor is grounded.

6. The PZT driving circuit for a tunable laser of claim 1, wherein the first power supply circuit includes a first power supply chip, a third capacitor, a first resistor, and a second variable resistor;

the first power chip comprises a first input pin, a first turn-off pin, a first output pin and a first adjustable voltage pin;

the first input pin and the first turn-off pin are electrically connected with the first power signal input end;

the first output pin is electrically connected with the first ends of the third capacitor and the second variable resistor respectively, and the first adjustable voltage pin is electrically connected with the second end of the third capacitor; the first adjustable voltage pin is electrically connected with a first end of the first resistor and an adjusting end of the second variable resistor, and a second end of the first resistor is grounded; the second end of the second variable resistor is arranged in a floating mode.

7. The PZT driving circuit for a tunable laser of claim 6, wherein the first power supply circuit further includes a fourth capacitor;

the first end of the fourth capacitor is electrically connected with the first output pin, and the second end of the fourth capacitor is grounded.

8. The PZT driving circuit for a tunable laser of claim 1, wherein the second power supply circuit includes a second power supply chip, a fifth capacitor, a second resistor, and a third resistor;

the second power chip comprises a second input pin, a second turn-off pin, a second output pin and a second adjustable voltage pin;

the second input pin and the second turn-off pin are respectively and electrically connected with the second power signal input end;

the second output pin is electrically connected with the first ends of the fifth capacitor and the third resistor respectively, and the second adjustable voltage pin is electrically connected with the second end of the fifth capacitor; the second adjustable voltage pin is electrically connected with the first end of the second resistor and the second end of the third resistor, and the second end of the second resistor is grounded.

9. The PZT driving circuit for a tunable laser of claim 8, wherein said second power supply circuit further includes a sixth capacitor;

the first end of the sixth capacitor is electrically connected with the second output pin, and the second end of the sixth capacitor is grounded.

10. A tunable laser, comprising: a laser body and PZT driving circuitry for a tunable laser according to any of claims 1-9;

the laser body includes at least a PZT load; a PZT drive circuit of the tunable laser is electrically connected to the PZT load.