Temperature control driving circuit applied to laser

Abstract

The utility model discloses a temperature control drive circuit applied to a laser, which belongs to the technical field of laser equipment and realizes temperature stabilization of a heat sink on a mounting surface of the laser. The device mainly comprises a machine shell, a semiconductor refrigerator TEC is arranged outside the machine shell, a heat sink is arranged on the semiconductor refrigerator TEC, a temperature sensor NTC is arranged on the heat sink, and the temperature sensor NTC controls the semiconductor refrigerator TEC through a drive circuit; the driving circuit comprises a PID circuit and an H-bridge circuit. The PID circuit outputs a switching signal CTRL to control the heat transfer direction of the TEC. According to the utility model, the temperature of the laser installation surface heat sink is collected, the current direction of the H-bridge circuit is controlled through the hardware PID circuit, and the semiconductor cooler TEC under the heat sink is driven, so that heat flow of the heat sink and the casing is realized, and the temperature stability of the laser installation surface heat sink is realized.

Description

TECHNICAL FIELD

[0001] The utility model relates to laser equipment technical field, concretely, especially, a kind of temperature control drive circuit applied to laser. BACKGROUND

[0002] Semiconductor laser is the important component of fiber sensing system, with higher electro-optic conversion efficiency, the performance and stability of semiconductor laser itself have important influence on the detection range, noise and sensitivity of system, but semiconductor laser is temperature sensitive device, temperature drift will affect the stability and reliability of device, so realizing accurate temperature control has very important role to semiconductor laser.

[0003] The performance parameters of semiconductor laser are greatly affected by temperature, output optical power, output wavelength, tuning range, etc. will be affected by temperature, commonly used first-order temperature control controls the TEC semiconductor cooler inside the laser to control the temperature of the laser. But the first-order temperature control will be affected by the change of external temperature, within the working temperature range, the laser appears the phenomenon of output optical power change, output wavelength jump mode section or drift, tuning range change. Therefore, increase the secondary temperature control, reduce the influence of external temperature change, expand the working temperature range of laser, suppress the above problems. The temperature control system of a laser light source disclosed in the prior art with publication number CN209805093U adopts a double-stage temperature control scheme, which can not only realize accurate control of the temperature conditions of the temperature control system, but also can realize accurate control of the temperature of the temperature control system under the condition that the environmental temperature conditions are uncontrollable. It lacks a specific implementation circuit. UTILITY MODEL CONTENT

[0004] The utility model aims at providing a kind of temperature control drive circuit applied to laser, realize the temperature stability of laser installation surface heat sink.

[0005] The utility model is realized by the following technical solutions:

[0006] A kind of temperature control drive circuit applied to laser, including casing, the casing is equipped with semiconductor refrigerator TEC, semiconductor refrigerator TEC is equipped with heat sink, heat sink is equipped with temperature sensor NTC, temperature sensor NTC controls semiconductor refrigerator TEC by drive circuit;The drive circuit includes PID circuit and H bridge circuit, PID circuit is connected to H bridge circuit, H bridge circuit is connected to semiconductor refrigerator TEC.

[0007] Further, the PID circuit comprises an operational amplifier U4 and an operational amplifier U3, the temperature sensor NTC is electrically connected to the negative input end of the operational amplifier U4, and the output end of the operational amplifier U4 is connected to the resistance R8; the resistance R8 is connected in parallel with the capacitor C2 and the resistance R11, and the capacitor C2 and the resistance R11 are connected in series; the resistance R8 is connected to the negative input end of the operational amplifier U3; the resistance R12 and the capacitor C3 are connected in parallel between the negative input end and the output end of the operational amplifier U3.

[0008] Further, the output end of the operational amplifier U3 is connected with the comparator U2, the output end of the comparator U2 outputs a switch signal CTRL1; the output end of the comparator U2 is connected with the negative input end of the comparator U1, and the output end of the comparator U1 outputs a switch signal CTRL2.

[0009] Further, the H bridge circuit comprises MOS tubes Q1, Q2, Q3 and Q4; the comparator U2 is electrically connected to the gate of the MOS tube Q2 and the MOS tube Q3, and the comparator U1 is electrically connected to the gate of the MOS tube Q1 and the MOS tube Q4; the drain of the MOS tube Q1 and the MOS tube Q2 is connected to the power supply voltage VCC, the source of the MOS tube Q1 and the MOS tube Q2 is connected to the drain of the MOS tube Q3 and the MOS tube Q4 respectively, and the source of the MOS tube Q3 and the MOS tube Q4 is grounded; the negative electrode of the semiconductor refrigerator TEC is electrically connected between the source of the MOS tube Q1 and the drain of the MOS tube Q3, and the positive electrode of the semiconductor refrigerator TEC is electrically connected between the source of the MOS tube Q2 and the drain of the MOS tube Q4.

[0010] Further, the gate of the MOS tube Q1 is connected with the resistance R14, the gate of the MOS tube Q2 is connected with the resistance R15, the gate of the MOS tube Q3 is connected with the resistance R16, and the gate of the MOS tube Q4 is connected with the resistance R17.

[0011] Further, the negative input end of the comparator U2 is connected with the resistance R7; and the negative input end of the comparator U1 is connected with the resistance R6.

[0012] Further, the capacitor C1 is connected in parallel between the negative input end and the output end of the operational amplifier U3.

[0013] Compared with the prior art, the utility model has the advantages of:

[0014] The utility model collects the temperature of the heat sink of the laser installation surface, controls the current direction of the H bridge circuit through the hardware PID circuit, drives the semiconductor refrigerator TEC under the heat sink, makes the heat sink and the shell flow, realizes the temperature stability of the laser installation surface heat sink. Attached Figure Description

[0015] Fig. 1 This is a schematic diagram of the PID circuit of this utility model;

[0016] Fig. 2 This is a schematic diagram of the H-bridge circuit of this utility model;

[0017] Fig. 3 This is a structural block diagram of the present invention. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solution of this utility model, the technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings. Based on the embodiments in this application, other similar embodiments obtained by those skilled in the art without creative effort should all fall within the scope of protection of this application. Furthermore, the directional terms mentioned in the following embodiments, such as "up," "down," "left," and "right," are only for reference to the directions in the accompanying drawings. Therefore, the directional terms used are for illustrative purposes and not for limiting the creation of this utility model.

[0019] The present invention will be further described below with reference to the accompanying drawings.

[0020] Example 1: A temperature control drive circuit applied to a laser, such as... Figs. 1-3 As shown, the system includes a housing, outside which is a semiconductor cooler (TEC). A heat sink is mounted on the TEC, and a temperature sensor (NTC) is mounted on the heat sink. The NTC controls the TEC via a drive circuit. The drive circuit includes a PID circuit and an H-bridge circuit. The PID circuit is connected to the H-bridge circuit, which in turn is connected to the TEC. The NTC monitors the temperature of the heat sink in real time and feeds the signal back to the PID circuit. The PID circuit, through a proportional-integral-derivative (PI) control algorithm, precisely adjusts the operating state of the TEC, ensuring that the laser's operating temperature remains stable near the set value and preventing temperature fluctuations from affecting laser performance.

[0021] Embodiment 2, a temperature control driving circuit applied to a laser, the operational amplifier U4 and the operational amplifier U3 in the PID circuit can realize precise feedback control through the combination of resistors and capacitors, ensuring the rapid response and stability of temperature control. The PID circuit includes the operational amplifier U4 and the operational amplifier U3, the temperature sensor NTC is electrically connected to the negative input end of the operational amplifier U4, and the output end of the operational amplifier U4 is connected to the resistor R8; the resistor R8 has the capacitor C2 and the resistor R11 connected in parallel across the resistor R8, and the capacitor C2 is connected in series with the resistor R11; the resistor R8 is connected to the negative input end of the operational amplifier U3; the resistor R12 and the capacitor C3 are connected in parallel between the negative input end and the output end of the operational amplifier U3, and the resistor R12 is connected in series with the capacitor C3.

[0022] The comparator U2 and the comparator U1 can quickly respond to the output signal of the PID circuit to generate the switching signal CTRL1 and the switching signal CTRL2, which control the current direction in the H-bridge circuit. This fast switching ensures that the TEC can quickly respond to temperature changes and reduce the delay of temperature adjustment. The output end of the operational amplifier U3 is connected to the comparator U2, and the output end of the comparator U2 outputs the switching signal CTRL1; the output end of the comparator U2 is connected to the negative input end of the comparator U1, and the output end of the comparator U1 outputs the switching signal CTRL2.

[0023] The H-bridge circuit is composed of four MOS transistors (Q1, Q2, Q3, Q4), which can change the current direction by controlling the switching state of the MOS transistors, thereby controlling the cooling or heating function of the TEC. This bidirectional control enables the system to quickly adjust the temperature according to actual needs, both cooling and heating, adapting to different working environments. The H-bridge includes MOS transistor Q1, MOS transistor Q2, MOS transistor Q3, and MOS transistor Q4; the comparator U2 is electrically connected to the gates of MOS transistor Q2 and MOS transistor Q3, and the comparator U1 is electrically connected to the gates of MOS transistor Q1 and MOS transistor Q4; the drains of MOS transistor Q1 and MOS transistor Q2 are connected to the power supply voltage VCC, which is 5V, and the sources of MOS transistor Q1 and MOS transistor Q2 are respectively connected to the drains of MOS transistor Q3 and MOS transistor Q4, and the sources of MOS transistor Q3 and MOS transistor Q4 are grounded; the negative electrode of the semiconductor refrigerator TEC is electrically connected between the source of MOS transistor Q1 and the drain of MOS transistor Q3, and the positive electrode of the semiconductor refrigerator TEC is electrically connected between the source of MOS transistor Q2 and the drain of MOS transistor Q4.

[0024] The gate of MOS transistor Q1 is connected to resistor R14, the gate of MOS transistor Q2 is connected to resistor R15, the gate of MOS transistor Q3 is connected to resistor R16, and the gate of MOS transistor Q4 is connected to resistor R17.

[0025] The negative input terminal of the comparator U2 is connected with the resistor R7; the negative input terminal of the comparator U1 is connected with the resistor R6. The negative input terminal and the output terminal of the operational amplifier U3 are connected in parallel with the capacitor C1, which can effectively filter high-frequency noise, ensure the stability of the signal, and further improve the response speed of the system.

[0026] The other is the same as that of Example 1.

[0027] The thermal feedback voltage of the temperature sensor NTC enters the negative input terminal of the operational amplifier U4, and the heat sink temperature setting voltage enters the positive input terminal of the operational amplifier U4, which are compared to generate an error voltage, which enters the negative input terminal of the operational amplifier U3. The resistor R8 sets the proportion, the capacitor C2 and the resistor R11 set the differential, and the capacitor C3 and the resistor R12 set the integral, which constitute a PID compensator with the operational amplifier U3. The output signal of the operational amplifier U3 enters the negative input terminal of the comparator U2, and the switch signal CTRL1 is output through comparison. The output signal of the comparator U2 enters the negative input terminal of the comparator U1, and the switch signal CTRL2 is output through comparison.

[0028] The switch signals CTRL1 and CTRL2 control the H-bridge circuit, change the direction of the current, control the heat transfer direction of the semiconductor refrigerator TEC, and stabilize the heat sink temperature at the set temperature.

[0029] The resistance and capacitance (capacitor C2, capacitor C3, resistor R8, resistor R11 and resistor R12) of the PID circuit are adjusted to balance the stability and response speed of the system. The series resistance (resistor R14, resistor R15, resistor R16 and resistor R17) before the MOS tube in the H-bridge resistor is adjusted to control the H-bridge power supply current, so that the semiconductor refrigerator TEC works at an appropriate current.

[0030] The above has made a detailed description of the utility model, and the above is only a preferred embodiment of the utility model, which cannot limit the scope of the utility model. Any equivalent changes and modifications made within the scope of the application shall still fall within the scope of the utility model.

Claims

1. A temperature control driving circuit applied to a laser, comprising a casing, characterized in that: The shell is externally provided with a semiconductor cooler TEC, a heat sink is arranged on the semiconductor cooler TEC, a temperature sensor NTC is arranged on the heat sink, and the temperature sensor NTC controls the semiconductor cooler TEC through a driving circuit; the driving circuit comprises a PID circuit and an H-bridge circuit, the PID circuit is connected to the H-bridge circuit, and the H-bridge circuit is connected to the semiconductor cooler TEC.

2. The temperature control driving circuit applied to a laser diode as claimed in claim 1, wherein: The PID circuit comprises an operational amplifier U4 and an operational amplifier U3, the temperature sensor NTC is electrically connected to the negative input end of the operational amplifier U4, and the output end of the operational amplifier U4 is connected to a resistor R8; the resistor R8 is connected in parallel with a capacitor C2 and a resistor R11 at both ends, and the capacitor C2 and the resistor R11 are connected in series; the resistor R8 is connected to the negative input end of the operational amplifier U3; the resistor R12 and the capacitor C3 are connected in parallel between the negative input end and the output end of the operational amplifier U3.

3. The temperature control driving circuit applied to a laser diode as claimed in claim 2, wherein: The output end of the operational amplifier U3 is connected to a comparator U2, and the output end of the comparator U2 outputs a switching signal CTRL1; the output end of the comparator U2 is connected to the negative input end of a comparator U1, and the output end of the comparator U1 outputs a switching signal CTRL2.

4. The temperature control driving circuit applied to a laser diode as claimed in claim 1, wherein: The H-bridge circuit comprises MOS tubes Q1, Q2, Q3 and Q4; the comparator U2 is electrically connected to the gates of the MOS tubes Q2 and Q3, and the comparator U1 is electrically connected to the gates of the MOS tubes Q1 and Q4; the drain electrodes of the MOS tubes Q1 and Q2 are connected to a power supply voltage VCC, the source electrodes of the MOS tubes Q1 and Q2 are connected to the drain electrodes of the MOS tubes Q3 and Q4 respectively, and the source electrodes of the MOS tubes Q3 and Q4 are grounded; the negative electrode of the semiconductor cooler TEC is electrically connected between the source electrode of the MOS tube Q1 and the drain electrode of the MOS tube Q3, and the positive electrode of the semiconductor cooler TEC is electrically connected between the source electrode of the MOS tube Q2 and the drain electrode of the MOS tube Q4.

5. The temperature control driving circuit applied to a laser diode as claimed in claim 4, wherein: The gate electrode of the MOS tube Q1 is connected to a resistor R14, the gate electrode of the MOS tube Q2 is connected to a resistor R15, the gate electrode of the MOS tube Q3 is connected to a resistor R16, and the gate electrode of the MOS tube Q4 is connected to a resistor R17.

6. The temperature control driving circuit applied to a laser diode as claimed in claim 3, wherein: The negative input end of the comparator U2 is connected to a resistor R7, and the negative input end of the comparator U1 is connected to a resistor R6.

7. The temperature control driving circuit applied to a laser diode as claimed in claim 2, wherein: The capacitor C1 is connected in parallel between the negative input and output ends of the operational amplifier U3.

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