Temperature monitoring stable power supply circuit

Abstract

The embodiment of the utility model discloses a temperature monitoring stable power supply circuit, which relates to the technical field of power supply, is used for supplying power to a temperature sampling module, and comprises a power supply module, a transformer output module, a control module and a power supply feedback module, the power supply module is connected with the transformer output module and the control module, the control module is connected with the transformer output module, the transformer output module is connected with the temperature sampling module, and the power supply feedback module is respectively connected with the transformer output module and the control module. The power supply feedback module is used for monitoring the voltage output by the transformer output module to the temperature sampling module and feeding back the voltage to the control module, so that when the voltage output by the transformer output module deviates, the control module can adjust the voltage output by the transformer output module at the first time; the stability of the voltage output by the transformer output module is ensured, and then the sampling precision of the temperature sampling module is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of power supply, in particular to a temperature monitoring and stable power supply circuit. Background Art

[0002] Temperature is one of the commonly used control variables in industrial control systems. Most industrial sites use non-contact temperature measurement methods, such as thermal effect method, thermal resistance method, etc. Among them, the thermal resistance method is more widely used in industrial applications, but this method mainly uses resistor voltage division and then amplification by operational amplifier to transmit to the sampling chip, so it has high requirements on the accuracy of the power supply.

[0003] A switching power supply is a type of power supply that uses modern power electronics technology to control the time ratio of the switch on and off to maintain a stable output voltage. It is generally composed of a PWM control chip and MOS. However, the existing power supply output circuit only relies on the transformer's own turns ratio for output distribution. When the corresponding load changes, it cannot output stably, which easily leads to problems such as accuracy deviation and weak stability in the subsequent circuit. Utility Model Content

[0004] The technical problem to be solved by the embodiments of the utility model is how to provide stability of the power supply of the temperature monitoring circuit.

[0005] In order to solve the above problems, the embodiment of the utility model proposes a temperature monitoring stable power supply circuit, which is used to power a temperature sampling module. The temperature monitoring stable power supply circuit includes a power supply module, a transformer output module, a control module and a power supply feedback module;

[0006] The power supply module is connected to the transformer output module and the control module, the control module is connected to the transformer output module, the transformer output module is connected to the temperature sampling module, and the power supply feedback module is respectively connected to the transformer output module and the control module.

[0007] Its further technical solution is that the power supply module includes a voltage source and a first resistor, the control module includes a control chip, the transformer output module includes a transformer, the voltage source is connected to the control chip through the first resistor, and the voltage source is connected to the primary winding of the transformer.

[0008] A further technical solution is that the control module also includes a second resistor and a switch tube, the control chip is connected to the control end of the switch tube through the second resistor, the input end of the switch tube is connected to the primary winding of the transformer, and the output end of the switch tube is grounded.

[0009] Its further technical solution is that the transformer output module also includes a buffer absorption unit, which includes a third resistor, a first capacitor and a fourth diode, the third resistor is respectively connected to the voltage source and the negative electrode of the fourth diode, the first capacitor is connected in parallel with the third resistor, and the positive electrode of the fourth diode is connected to the input end of the switching tube.

[0010] Its further technical solution is that the transformer also includes a first secondary winding, and the transformer output module also includes a first diode and a second capacitor; the positive pole of the first diode is connected to the first secondary winding, and the negative pole of the first diode is connected to the temperature sampling module; the two ends of the second capacitor are respectively connected to the two ends of the first secondary winding.

[0011] Its further technical solution is that the transformer output module also includes a fourth resistor, a fifth resistor and a third diode; the cathode of the first diode is connected to the temperature sampling module through the fourth resistor; the fifth resistor is connected to the fourth resistor and grounded; the cathode of the third diode is connected to the fourth resistor, and the anode of the third diode is grounded.

[0012] Its further technical solution is that the transformer also includes a second secondary winding, and the transformer output module also includes a second diode and a third capacitor; the second secondary winding is connected to the positive electrode of the second diode, and the negative electrode of the second diode is connected to the control chip; the two ends of the third capacitor are respectively connected to the two ends of the second secondary winding.

[0013] A further technical solution is that the transformer output module also includes a sixth resistor, and the sixth resistor is connected in parallel with the third capacitor.

[0014] Its further technical solution is that the power feedback module includes a seventh resistor, an eighth resistor, a voltage stabilizing device and a photoelectric coupler; the positive electrode of the light-emitting diode of the primary side of the photoelectric coupler is connected to the first secondary winding, and the secondary side of the photoelectric coupler is connected to the control chip; the first end of the seventh resistor is connected to the first secondary winding, and the second end of the seventh resistor is respectively connected to the eighth resistor and the reference end of the voltage stabilizing device; the eighth resistor is grounded; the anode of the voltage stabilizing device is connected to the negative electrode of the light-emitting diode of the primary side of the photoelectric coupler, and the cathode of the voltage stabilizing device is grounded;

[0015] The power feedback module also includes a ninth resistor and a tenth resistor, and the positive electrode of the primary side light-emitting diode of the photoelectric coupler is connected to the first secondary winding through the ninth resistor; the two ends of the tenth resistor are respectively connected to the positive electrode and the negative electrode of the primary side light-emitting diode of the photoelectric coupler.

[0016] Its further technical solution is that the temperature sampling module includes a dip switch, a first temperature sampling resistor, a second temperature sampling resistor, a first sampling unit, a second sampling unit and an AD sampling chip; the fixed end of the dip switch is used to connect to the input end, the first active end of the dip switch is connected to the first temperature sampling resistor, and the second active end of the dip switch is connected to the second temperature sampling resistor; the first temperature sampling resistor is connected to the AD sampling chip through the first sampling unit, and the second temperature sampling resistor is connected to the AD sampling chip through the second sampling unit; the transformer output module is connected to the first sampling unit and the second sampling unit respectively.

[0017] Compared with the prior art, the technical effects that can be achieved by the embodiments of the present invention include:

[0018] In an embodiment of the utility model, the power supply feedback module is used to monitor the voltage output by the transformer output module to the temperature sampling module and feed it back to the control module, so that when the voltage output by the transformer output module deviates, the control module can adjust the voltage output by the transformer output module in the first time, thereby ensuring the stability of the voltage output by the transformer output module and further ensuring the sampling accuracy of the temperature sampling module. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings herein are incorporated in and constitute a part of the specification, illustrate embodiments consistent with the present utility model, and together with the description, are used to explain the principles of the present utility model.

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the utility model or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0021] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0022] Figure 1 A circuit block diagram of a temperature monitoring stable power supply circuit provided by an embodiment of the utility model;

[0023] Figure 2 A circuit diagram of a temperature monitoring stable power supply circuit provided by an embodiment of the utility model;

[0024] Figure 3A circuit diagram of a power supply feedback module of a temperature monitoring stable power supply circuit provided by an embodiment of the utility model;

[0025] Figure 4 A circuit diagram of a temperature sampling module of a temperature monitoring stable power supply circuit provided by an embodiment of the utility model.

[0026] Reference numerals

[0027] A power supply module 100, a transformer output module 200, a control module 300, a power supply feedback module 400, a temperature sampling module 500, a voltage source VCC1, a first resistor R1, a control chip U1, a transformer T1, a primary winding T11, a primary winding T11, a first secondary winding T12, a second secondary winding T13, a second resistor R2, a switch tube Q1, a third resistor R3, a first capacitor C1, a fourth diode D31, a first diode D21, a second capacitor C2, a fourth resistor R4, a fifth resistor R5, a third diode D23, a second diode D22, a third capacitor C3, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a voltage stabilizing device U2, a photocoupler O1, a ninth resistor R9, and a tenth resistor R10. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments. Similar component numbers in the drawings represent similar components. Obviously, the embodiments to be described below are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0029] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0030] It should also be understood that the terms used in this utility model embodiment specification are only for the purpose of describing specific embodiments and are not intended to limit the utility model embodiments. As used in the utility model embodiment specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0031] See also Figure 1-4The embodiment of the utility model provides a temperature monitoring stable power supply circuit for supplying power to a temperature sampling module 500. The temperature monitoring stable power supply circuit includes a power supply module 100, a transformer output module 200, a control module 300 and a power supply feedback module 400.

[0032] The power module 100 is used to provide power output for use by the transformer output module 200. The power module 100 is connected to the transformer output module 200 and the control module 300 to provide power.

[0033] The control module 300 is connected to the transformer output module 200 and is used to adjust the output of the transformer output module 200 .

[0034] The transformer output module 200 is connected to the temperature sampling module 500 and is used to supply power to the temperature sampling module 500. The temperature sampling module 500 is used to collect temperature information.

[0035] The power feedback module 400 is respectively connected to the transformer output module 200 and the control module 300. The power feedback module 400 is used to monitor the voltage output by the transformer output module 200 to the temperature sampling module 500, and feed it back to the control module 300, so that when the voltage output by the transformer output module 200 deviates, the control module 300 can adjust the voltage output by the transformer output module 200 in the first time, ensuring the stability of the voltage output by the transformer output module 200, and further ensuring the sampling accuracy of the temperature sampling module 500.

[0036] In one embodiment, further, the power module 100 includes a voltage source VCC1 and a first resistor R1, the control module 300 includes a control chip U1, and the transformer output module 200 includes a transformer T1. The voltage source VCC1 is connected to the control chip U1 through the first resistor R1 (specifically connected to the VCC pin of the control chip U1), and the voltage source VCC1 is connected to the primary winding T11 of the transformer T1. The voltage source VCC1 is grounded through a fourth capacitor C4.

[0037] The model of the control chip U1 may be UC3844. By adjusting the resistor and capacitor configured at pin 4 (RT / CT pin) of the control chip U1, the internal oscillation frequency and duty cycle thereof can be controlled, thereby controlling the switching frequency of the switch tube Q1.

[0038] The voltage source VCC1 may be a direct current power source. The voltage source VCC1 supplies power to the control chip U1 through the first resistor R1. At the same time, the voltage source VCC1 supplies power to the primary winding T11 of the transformer T1.

[0039] Furthermore, the control module 300 further includes a second resistor R2 and a switch tube Q1, the control chip U1 is connected to the control end of the switch tube Q1 through the second resistor R2, the input end of the switch tube Q1 is connected to the primary winding T11 of the transformer T1, and the output end of the switch tube Q1 is grounded. Specifically, the output end of the switch tube Q1 is grounded through a thirty-third resistor R33.

[0040] Specifically, the control chip U1 outputs a PWM driving signal to the switch tube Q1 through the second resistor R2, thereby adjusting the output of the transformer T1.

[0041] It should be noted that the switch tube Q1 can be specifically an NMOS tube, the control end of the switch tube Q1 is the gate of the NMOS tube, the input end of the switch tube Q1 is the drain of the NMOS tube, and the output end of the switch tube Q1 is the source of the NMOS tube.

[0042] Furthermore, the transformer output module 200 also includes a buffer absorption unit, which includes a third resistor R3, a first capacitor C1 and a fourth diode D31, the third resistor R3 is respectively connected to the voltage source VCC1 and the cathode of the fourth diode D31, the first capacitor C1 is connected in parallel with the third resistor R3, and the anode of the fourth diode D31 is connected to the input end of the switch tube Q1.

[0043] Specifically, the excitation inductance of the secondary winding of the transformer T1 is magnetically reset through the buffer absorption unit to absorb and feed back the residual magnetic energy; at the same time, it can avoid adverse phenomena such as bias magnetization and excessive voltage spikes in the transformer T1 during operation.

[0044] Furthermore, the transformer T1 also includes a first secondary winding T12, and the transformer output module 200 also includes a first diode D21, a second capacitor C2, a fourth resistor R4, a fifth resistor R5 and a third diode D23; the positive electrode of the first diode D21 is connected to the first secondary winding T12, and the negative electrode of the first diode D21 is connected to the temperature sampling module 500; the two ends of the second capacitor C2 are respectively connected to the two ends of the first secondary winding T12.

[0045] Specifically, the cathode of the first diode D21 is connected to the temperature sampling module 500 through the fourth resistor R4; the fifth resistor R5 is connected to the fourth resistor R4 and grounded; the cathode of the third diode D23 is connected to the fourth resistor R4, and the anode of the third diode D23 is grounded. Specifically, the first diode D21 plays a role of unidirectional current flow. The second capacitor C2 plays a role of energy storage. The first secondary winding T12 is used to supply power to the temperature sampling module 500, specifically to output a stable 5V voltage.

[0046] Further, the transformer T1 also includes a second secondary winding T13, and the transformer output module 200 also includes a second diode D22, a third capacitor C3 and a sixth resistor R6; the second secondary winding T13 is connected to the positive electrode of the second diode D22, and the negative electrode of the second diode D22 is connected to the control chip U1 (specifically connected to the VCC pin of the control chip U1); the two ends of the third capacitor C3 are respectively connected to the two ends of the second secondary winding T13. The sixth resistor R6 is connected in parallel with the third capacitor C3. Specifically, the second diode D22 plays a role in unidirectional flow of current. The third capacitor C3 plays a role in energy storage. The second secondary winding T13 is used to supply power to the control chip U1.

[0047] Further, the power feedback module 400 includes a seventh resistor R7, an eighth resistor R8, a voltage stabilizer U2, a photocoupler O1, a ninth resistor R9 and a tenth resistor R10; the positive electrode of the primary side light emitting diode of the photocoupler O1 is connected to the first secondary winding T12, and the secondary side of the photocoupler O1 is connected to the control chip U1 (specifically, pin 4 of the photocoupler O1 is connected to pin 1 of the control chip U1); the first end of the seventh resistor R7 is connected to the first secondary winding T12 (specifically, the first end of the seventh resistor R7 is connected to the fourth resistor R4), and the second end of the seventh resistor R7 is respectively connected to the eighth resistor R8 and the reference end of the voltage stabilizer U2; the eighth resistor R8 is grounded; the anode of the voltage stabilizer U2 is connected to the negative electrode of the primary side light emitting diode of the photocoupler O1, and the cathode of the voltage stabilizer U2 is grounded.

[0048] Further, the positive electrode of the primary side light emitting diode of the photocoupler O1 is connected to the first secondary winding T12 through the ninth resistor R9 (specifically, the ninth resistor R9 is connected to the fourth resistor R4); the two ends of the tenth resistor R10 are respectively connected to the positive electrode and the negative electrode of the primary side light emitting diode of the photocoupler O1. The model of the voltage regulator U2 can be TL341.

[0049] The working principle of the power supply feedback module 400 is as follows: the first secondary winding T12 supplies power to the primary side of the photocoupler O1, and at the same time, after being divided by the seventh resistor R7 and the eighth resistor R8, the voltage is compared with the internal reference voltage of the voltage regulator U2, thereby changing the voltage of the negative electrode of the light-emitting diode on the primary side of the photocoupler O1, thereby causing the voltage of pin 4 on the secondary side of the photocoupler O1 to change, and the voltage is input to the voltage feedback pin of the control chip U1 (pin 1 of the control chip U1). At this time, the control chip U1 will adjust the output to change the duty cycle to achieve the purpose of output voltage stability.

[0050] See also Figure 4 In one embodiment, the temperature sampling module 500 includes a dip switch S11, a first temperature sampling resistor KTY84, a second temperature sampling resistor PT100, a first sampling unit 510, a second sampling unit 520 and an AD sampling chip U3; the fixed end 11 of the dip switch S11 is used to connect to the input end IN, the first active end 12 of the dip switch S11 is connected to the first temperature sampling resistor KTY84, and the second active end 13 of the dip switch S11 is connected to the second temperature sampling resistor PT100; the first temperature sampling resistor KTY84 is connected to the AD sampling chip U3 through the first sampling unit 510, and the second temperature sampling resistor PT100 is connected to the AD sampling chip U3 through the second sampling unit 520; the transformer output module 200 is connected to the first sampling unit 510 and the second sampling unit 520 respectively.

[0051] The first temperature sampling resistor KTY84 and the second temperature sampling resistor PT100 are switched by the DIP switch S11, so as to cope with different usage scenarios. For example, at low temperatures (temperature less than 0°C), the first temperature sampling resistor KTY84 has high accuracy, so the resistor is switched to the first temperature sampling resistor KTY84. Otherwise, the resistor is switched to the second temperature sampling resistor PT100, thereby achieving high-precision sampling in the full temperature range. The following is an example of the first temperature sampling resistor KTY84. The 5V voltage output by the first secondary winding T12 is divided by the first temperature sampling resistor KTY84 and the eleventh resistor R11, the fourteenth resistor R14, and the sixteenth resistor R16 to obtain the positive input voltage of the operational amplifier U10. The 5V voltage output by the first secondary winding T12 is also divided by the twelfth resistor R12, the thirteenth resistor R13, and the fifteenth resistor R15 to obtain the negative input voltage of the operational amplifier U10. Then, the relationship between the input and output of the operational amplifier U10 is obtained based on the virtual short and virtual break. Then, the voltage corresponding to different temperatures can be obtained based on the relationship between the resistance value and temperature of the temperature sampling resistor KTY84, and then fed back to the AD sampling chip U3, and the AD sampling chip U3 transmits the relevant information to the external IC. It should be noted that the structure of the above-mentioned temperature sampling module is only an example. The utility model is intended to provide a stable power input for the temperature sampling module, and the structure of the temperature sampling module is not specifically limited.

[0052] The working process of the above temperature monitoring stable power supply circuit can be specifically divided into the following four stages:

[0053] Phase 1: The voltage source VCC1 supplies power to the driver chip U1 through the first resistor R1. The driver chip U1 outputs a PWM drive signal of a high level to turn on the switch tube Q1. At the same time, the primary winding T11 of the transformer T1 is powered to store energy. At this time, the first secondary winding T12 and the second secondary winding T13 of the transformer T1 are not conducting because the first diode D21 and the second diode D22 are subjected to reverse voltage. Therefore, the second capacitor C2 and the third capacitor C3 supply energy to the load (temperature sampling module 500 and the driver chip U1).

[0054] The second stage: when the PWM driving signal output by the driver chip U1 becomes a low level, the switch tube Q1 is turned off, there is no current in the primary winding T11, and the magnetic field begins to weaken, thereby generating a forward electromotive force in the first secondary winding T12 and the second secondary winding T13, and the first diode D21 and the second diode D22 are turned on to supply power to the driver chip U1, and at the same time generate a 5V voltage to supply power to the temperature sampling module 500, and at the same time charge the second capacitor C2 and the third capacitor C3.

[0055] The third stage: the PWM drive signal output by the driver chip U1 is still at a low level, and the output voltage of 5V starts to power the primary side of the photocoupler O1. At the same time, after the voltage is divided by the seventh resistor R7 and the eighth resistor R8, it is compared with the internal reference voltage of the voltage regulator U2, changing the voltage of the negative electrode of the light-emitting diode of the primary side of the photocoupler O1, thereby causing the voltage of the pin 4 of the secondary side of the photocoupler O1 to change, and input to the voltage feedback pin of the control chip U1 (pin 1 of the control chip U1). At this time, the control chip U1 will adjust the output to change the duty cycle to achieve the purpose of output voltage stability. At the same time, the excitation inductance of the secondary winding T12 of the transformer T1 is magnetically reset through the buffer absorption unit to absorb and feedback the residual magnetic energy; after this working stage is completed, the working process will transition back to the first stage.

[0056] The fourth stage: The first three stages provide a stable and reliable 5V voltage input for the fourth stage, and the switching of the first temperature sampling resistor KTY84 and the second temperature sampling resistor PT100 is realized by the dial switch S11. The first temperature sampling resistor KTY84 is used as an example for explanation below. The 5V voltage output by the first secondary winding T12 is divided by the first temperature sampling resistor KTY84 and the eleventh resistor R11, the fourteenth resistor R14, and the sixteenth resistor R16 to obtain the positive input voltage of the operational amplifier U10. The 5V voltage output by the first secondary winding T12 is also divided by the twelfth resistor R12, the thirteenth resistor R13, and the fifteenth resistor R15 to obtain the negative input voltage of the operational amplifier U10. Then, the relationship between the input and output of the operational amplifier U10 is obtained based on the virtual short and virtual break. Then, the voltage corresponding to different temperatures can be obtained based on the relationship between the resistance value and temperature of the first temperature sampling resistor KTY84, and then fed back to the AD sampling chip U3, and the AD sampling chip U3 transmits the relevant information to the external IC.

[0057] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0058] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0059] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0060] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be connected, detachably connected, or integrated; it can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0061] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0062] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms should not be understood as necessarily being directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification.

[0063] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is intended to include these modifications and variations.

[0064] The above is a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the utility model, and these modifications or replacements should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. A temperature monitoring stable power supply circuit, characterized in that: Used to power the temperature sampling module, the temperature monitoring stable power supply circuit includes a power supply module, a transformer output module, a control module and a power supply feedback module; The power supply module is connected to the transformer output module and the control module, the control module is connected to the transformer output module, the transformer output module is connected to the temperature sampling module, and the power supply feedback module is respectively connected to the transformer output module and the control module.

2. The temperature monitoring stable power supply circuit according to claim 1, characterized in that: The power supply module includes a voltage source and a first resistor, the control module includes a control chip, the transformer output module includes a transformer, the voltage source is connected to the control chip through the first resistor, and the voltage source is connected to the primary winding of the transformer.

3. The temperature monitoring stable power supply circuit according to claim 2 is characterized in that: The control module also includes a second resistor and a switch tube. The control chip is connected to the control end of the switch tube through the second resistor. The input end of the switch tube is connected to the primary winding of the transformer, and the output end of the switch tube is grounded.

4. The temperature monitoring stable power supply circuit according to claim 3, characterized in that: The transformer output module also includes a buffer absorption unit, which includes a third resistor, a first capacitor and a fourth diode. The third resistor is connected to the voltage source and the cathode of the fourth diode respectively, the first capacitor is connected to the third resistor in parallel, and the anode of the fourth diode is connected to the input end of the switch tube.

5. The temperature monitoring stable power supply circuit according to claim 3, characterized in that: The transformer also includes a first secondary winding, and the transformer output module also includes a first diode and a second capacitor; the positive electrode of the first diode is connected to the first secondary winding, and the negative electrode of the first diode is connected to the temperature sampling module; the two ends of the second capacitor are respectively connected to the two ends of the first secondary winding.

6. The temperature monitoring stable power supply circuit according to claim 5, characterized in that: The transformer output module also includes a fourth resistor, a fifth resistor and a third diode; the cathode of the first diode is connected to the temperature sampling module through the fourth resistor; the fifth resistor is connected to the fourth resistor and grounded; the cathode of the third diode is connected to the fourth resistor, and the anode of the third diode is grounded.

7. The temperature monitoring stable power supply circuit according to claim 2, characterized in that: The transformer also includes a second secondary winding, and the transformer output module also includes a second diode and a third capacitor; the second secondary winding is connected to the positive electrode of the second diode, and the negative electrode of the second diode is connected to the control chip; the two ends of the third capacitor are respectively connected to the two ends of the second secondary winding.

8. The temperature monitoring stable power supply circuit according to claim 7, characterized in that: The transformer output module further includes a sixth resistor, and the sixth resistor is connected in parallel with the third capacitor.

9. The temperature monitoring stable power supply circuit according to claim 5, characterized in that: The power supply feedback module includes a seventh resistor, an eighth resistor, a voltage stabilizing device and a photoelectric coupler; the positive electrode of the light emitting diode of the primary side of the photoelectric coupler is connected to the first secondary winding, and the secondary side of the photoelectric coupler is connected to the control chip; the first end of the seventh resistor is connected to the first secondary winding, and the second end of the seventh resistor is respectively connected to the eighth resistor and the reference end of the voltage stabilizing device; the eighth resistor is grounded; the anode of the voltage stabilizing device is connected to the negative electrode of the light emitting diode of the primary side of the photoelectric coupler, and the cathode of the voltage stabilizing device is grounded; The power feedback module also includes a ninth resistor and a tenth resistor, and the positive electrode of the primary side light-emitting diode of the photoelectric coupler is connected to the first secondary winding through the ninth resistor; the two ends of the tenth resistor are respectively connected to the positive electrode and the negative electrode of the primary side light-emitting diode of the photoelectric coupler.

10. The temperature monitoring stable power supply circuit according to claim 1, characterized in that: The temperature sampling module includes a dip switch, a first temperature sampling resistor, a second temperature sampling resistor, a first sampling unit, a second sampling unit and an AD sampling chip; the fixed end of the dip switch is used to connect to the input end, the first active end of the dip switch is connected to the first temperature sampling resistor, and the second active end of the dip switch is connected to the second temperature sampling resistor; the first temperature sampling resistor is connected to the AD sampling chip through the first sampling unit, and the second temperature sampling resistor is connected to the AD sampling chip through the second sampling unit; the transformer output module is connected to the first sampling unit and the second sampling unit respectively.

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