Circuit for outputting autonomous continuous adjustable voltage

Abstract

The utility model relates to a circuit for outputting autonomous continuous adjustable voltage, which is characterized by comprising a reference voltage circuit unit, a temperature acquisition circuit unit, a voltage generation circuit unit, a voltage regulation circuit unit and a voltage acquisition circuit unit, the input end of the temperature acquisition single-path unit is connected with 3.3 V voltage, the output end of the temperature acquisition single-path unit is connected with an analog / digital conversion pin of the digital single-chip microcomputer, and the output end of the voltage regulation circuit unit is connected with the voltage generation circuit unit. The output end of the voltage generation circuit unit is connected with the power supply end of the silicon photomultiplier and the input end of the voltage acquisition circuit unit, and the output end of the voltage acquisition circuit unit is electrically connected with an analog-to-digital conversion pin of the digital single-chip microcomputer. According to the utility model, the output voltage consistency is good, the voltage value is continuously adjustable, the linear proportionality coefficient software is adjustable, and the voltage value is fed back in real time.

Description

Technical Field

[0001] This utility model relates to the field of power supply circuit technology, and in particular to a circuit that outputs an autonomously continuously adjustable voltage. Background Technology

[0002] The normal operation of electronic components depends on a stable and reliable power supply voltage. This is especially true for semiconductor sensors, whose characteristics are quite sensitive to temperature and power supply voltage. If the ambient temperature changes, in order to ensure that the sensor performance remains unchanged, the usual practice is to adjust its power supply voltage. This method of adjusting the power supply voltage can offset the impact of ambient temperature changes on sensor performance.

[0003] A basic voltage feedback voltage generation circuit is shown in the attached figure. Figure 1 As shown, this circuit can output a fixed voltage value. Existing adjustable voltage technology solutions are based on improvements to this circuit. The calculation relationship between the output voltage and the feedback resistor is shown in Equation 1:

[0004] .

[0005] In existing technical solutions, there are two main approaches to automatically adjust the output voltage based on ambient temperature.

[0006] Option 1, as attached Figure 2 The diagram shows an NTC voltage regulator circuit, which is based on a basic voltage feedback circuit. In the voltage feedback loop, a negative temperature coefficient thermistor (hereinafter referred to as NTC thermistor) is connected in parallel. The feedback loop characteristic of dynamically adjusting the output voltage by utilizing the change of the resistance value of the NTC thermistor with the ambient temperature is used to achieve the regulation of the output voltage.

[0007] The above-mentioned Option 1 has the following two drawbacks:

[0008] Disadvantage 1: The accuracy of the output voltage value is uncontrollable and the consistency is poor.

[0009] Because the resistance values ​​of NTC thermistors vary considerably from one to another, even NTC thermistors of the same specifications and model can exhibit significant differences in resistance values ​​at the same temperature. This leads to large differences in the feedback characteristics of the circuit, resulting in problems such as poor output voltage consistency and inaccurate and uncontrollable output voltage.

[0010] Disadvantage 2: The output voltage value changes non-linearly with temperature.

[0011] The resistance of NTC thermistor varies with temperature, which is not a linear relationship, and is a logarithmic function in theory, which is not conducive to the stability of the output of semiconductor sensor. For example, a silicon photomultiplier (SiPM) is used as a sensor to detect weak light signals. The manual of SiPM clearly indicates that the working voltage of SiPM is linearly positively correlated with the ambient temperature. The working voltage increases by 34.4 mV for every 1℃ increase in ambient temperature. The design method of this scheme obviously cannot achieve this linear relationship.

[0012] Scheme two, as shown in the accompanying Figure 3 Fig. 2, is a digital potentiometer voltage regulating circuit, which uses a digital potentiometer, a temperature sensor and a digital single-chip microcomputer to realize dynamic output voltage adjustment. The temperature sensor is used to collect the ambient temperature, and the digital single-chip microcomputer dynamically adjusts the resistance value of the digital potentiometer according to the ambient temperature. The feedback loop characteristics of the output voltage are changed, and the purpose of adjusting the output voltage can also be achieved.

[0013] The above-mentioned scheme two has the following two disadvantages:

[0014] Disadvantage 1: The output voltage value is not continuous due to the influence of the non-continuous resistance value output by the digital potentiometer, and only some discrete voltage values can be output.

[0015] This can be seen from equation 1. Because the digital potentiometer has limited resolution and cannot output continuous resistance values, the resistance value of the feedback resistor RFB1 is also discontinuous, which will result in discontinuous output voltage values. This is unacceptable for SiPM detectors.

[0016] Disadvantage 2: The cost of the scheme is too high, and the single-chip microcomputer resources are too much.

[0017] The cost of digital potentiometer is relatively high, especially for digital potentiometers with large range and high resolution, which are sold at around 10 yuan. This will lead to an increase in the total cost of the product. In addition, the digital potentiometer has a dedicated digital interface, which requires multiple IO ports of the single-chip microcomputer to operate, and the software control logic is complicated.

[0018] In view of the above-mentioned disadvantages of the existing two technical schemes, an improved circuit design scheme is designed, which combines a temperature sensor, a digital single-chip microcomputer and a software control method to realize the functions of good output voltage consistency, continuous adjustable voltage value, linear proportion coefficient software adjustable, and real-time feedback of voltage value. Content of the utility model

[0019] The utility model discloses a kind of output autonomous continuous adjustable voltage circuits, combining temperature sensor, digital single-chip microcomputer and software control method, realize the function of good output voltage consistency, voltage value continuous adjustable, linear proportion coefficient software adjustable, voltage value real-time feedback.

[0020] To achieve the above object, the technical scheme of the utility model is as follows:

[0021] A kind of output autonomous continuous adjustable voltage circuits, characterized by including reference voltage circuit unit, temperature acquisition circuit unit, voltage generation circuit unit, voltage regulating circuit unit, voltage acquisition circuit unit, the output end of the reference voltage circuit unit is electrically connected with the reference voltage pin of digital single-chip microcomputer, the input end of the temperature acquisition single circuit unit is connected with 3.3V voltage, the output end of the temperature acquisition circuit unit is connected with the analog / digital conversion pin of digital single-chip microcomputer, the output end of the voltage regulating circuit unit is connected with voltage generation circuit unit, the output end of the voltage generation circuit unit is connected with the power supply end of silicon photomultiplier and the input end of voltage acquisition circuit unit respectively, the output end of the voltage acquisition circuit unit is electrically connected with the analog-digital conversion pin of digital single-chip microcomputer.

[0022] The reference voltage circuit unit is composed of reference source chip REF3030, decoupling capacitor Cin and energy storage capacitor Cout, the input end of the reference source chip REF3030 is electrically connected with 3.3V voltage and decoupling capacitor Cin respectively, and the output end of the reference source chip REF3030 is connected with energy storage capacitor Cout and the reference voltage pin of digital single-chip microcomputer respectively.

[0023] The temperature acquisition circuit unit includes high-precision resistor R1, one end of the high-precision resistor R1 is connected with 3.3V voltage and decoupling capacitor C1 respectively, the other end of the high-precision resistor R1 is connected with current-limiting resistor R2 and thermistor Rntc respectively, and the current-limiting resistor R2 is connected with filter capacitor C2 and the analog / digital conversion pin of digital single-chip microcomputer respectively.

[0024] The voltage generation circuit unit includes boost type circuit and linear power step-down circuit, the input end of the boost type circuit is connected with 5V input voltage, the output end of the boost type circuit is connected with the input end of the linear power step-down circuit, and the output end of the linear power step-down circuit is electrically connected with the power supply end of silicon photomultiplier and the input end of voltage acquisition unit respectively.

[0025] The voltage boosting circuit comprises a voltage boosting chip SGM6601Y, the fifth pin of the voltage boosting chip SGM6601Y is connected with a 5V input voltage and a capacitor C8, the fourth pin of the voltage boosting chip SGM6601Y is connected with a resistor R7 and a resistor R8 respectively, the second pin of the voltage boosting chip SGM6601Y is grounded, the first pin of the voltage boosting chip SGM6601Y is connected with a capacitor C9, and the third pin of the voltage boosting chip SGM6601Y is connected with a resistor R9 and a resistor R10 respectively.

[0026] The linear power supply step-down circuit comprises a high-voltage linear power supply chip TPS7A4901, the fifth pin of the high-voltage linear power supply chip TPS7A4901 is connected with a starting resistor R11, the sixth pin of the high-voltage linear power supply chip TPS7A4901 is connected with a capacitor C11, the fourth pin of the high-voltage linear power supply chip TPS7A4901 is grounded, and the second pin of the high-voltage linear power supply chip TPS7A4901 is connected with a resistor R3 and a resistor R5 respectively.

[0027] The voltage regulating circuit unit comprises a resistor R6, a resistor R4 and a capacitor C4, one end of the resistor R4 is electrically connected with an analog voltage output pin of the digital single-chip microcomputer, the other end of the resistor R4 is connected with the resistor R6 and the capacitor C4 respectively, and the resistor R6 is electrically connected with the second pin of the high-voltage linear power supply chip TPS7A4901.

[0028] The voltage collecting circuit unit comprises a resistor R12, one end of the resistor R12 is connected with the output end of the voltage generating circuit and a capacitor C13 respectively, and the other end of the resistor R12 is connected with a resistor R13 in series.

[0029] The utility model discloses a temperature sensor, digital single-chip microcomputer and software control method are combined, realize output voltage consistency is good, voltage value continuous adjustable, linear proportion coefficient software adjustable, voltage value real-time feedback's function.

[0030] The circuit in the utility model discloses a negative temperature coefficient thermistor Rntc as a temperature sensor, which is a temperature sensor welded on a circuit board, and is located close to a silicon photomultiplier detector, and can truly reflect the temperature of the environment of the silicon photomultiplier.

[0031] The digital single-chip microcomputer in the circuit is a micro control unit (MCU), which has high-precision ADC and DAC peripheral functions. The software control method is a software code running in the MCU, which can realize software control functions of collecting temperature, adjusting output voltage and monitoring output voltage in real time.

[0032] The circuit of the utility model discloses, its output voltage after adjusting, the discrete type of voltage value individual between output is very small, voltage value continuous adjustable refers to the output voltage can be the arbitrary voltage value in the output range, is no longer only the voltage value of a series of discrete points can be outputted;

[0033] The circuit of the utility model discloses, its linear proportionality coefficient software adjustable refers to the linear relationship of temperature and output voltage can be controlled through software code, only need to change a coefficient in the code, can realize, voltage value real-time feedback refers to the digital single-chip microcomputer can real-time acquisition adjusted output voltage value, thereby further guaranteeing the consistency of output voltage value. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 It is basic voltage feedback type voltage generating circuit;

[0035] Figure 2 It is NTC voltage regulating circuit schematic diagram;

[0036] Figure 3 It is digital potentiometer voltage regulating circuit schematic diagram;

[0037] Figure 4 It is reference voltage circuit schematic diagram;

[0038] Figure 5 It is temperature acquisition circuit schematic diagram;

[0039] Figure 6 It is boost type circuit schematic diagram;

[0040] Figure 7 It is linear power supply step-down circuit schematic diagram;

[0041] Figure 8 It is linear power supply step-down circuit and voltage regulating circuit connection circuit schematic diagram;

[0042] Figure 9 It is voltage acquisition circuit schematic diagram;

[0043] Figure 10 It is software control flow schematic diagram. DETAILED DESCRIPTION

[0044] The technical scheme of the utility model will be described clearly and completely below in combination with the drawings, obviously, the described embodiment is a part of the embodiment of the utility model, rather than all the embodiment. Based on the embodiment in the utility model, all other embodiments obtained by the person skilled in the art without making creative labor belong to the scope of protection of the utility model.

[0045] Embodiment 1

[0046] The core of the improvement of the scheme mainly designs and implements the following five hardware circuit units: reference voltage circuit unit, temperature acquisition circuit unit, voltage generation circuit unit, voltage regulation circuit unit and voltage acquisition circuit unit. The specific implementation is introduced as follows.

[0047] The main function of the reference voltage circuit unit is to provide a reference voltage for the digital single-chip microcomputer, which must have the characteristics of high precision and low temperature drift coefficient. The input end of the reference voltage circuit unit is electrically connected with a 3.3V voltage, which is obtained by LDO voltage reduction from the supply voltage Vin. The output of the reference voltage circuit unit is electrically connected with the reference voltage pin of the digital single-chip microcomputer. As shown in Figure 4 , a reference source chip REF3030 is selected in the scheme. The output rated voltage value of the chip REF3030 is 3.0V, the output voltage precision is 0.2%, and the typical value of the temperature drift coefficient is 20ppm / ℃, which is very suitable for use as a reference source of the digital single-chip microcomputer. The input end of the chip REF3030 is connected with a decoupling capacitor Cin, which can filter out the noise components in the power supply, so that the power supply entering the chip is more stable. The output end of the chip REF3030 is connected with an energy storage capacitor Cout, which enhances the stability of the output voltage. The 3.0V voltage output by the REF3030 chip will be connected to the digital single-chip microcomputer as the reference voltage of the digital / analog converter of the digital single-chip microcomputer.

[0048] The temperature acquisition circuit unit can monitor the environmental temperature in real time. The input end of the temperature acquisition circuit unit is electrically connected with a 3.3V voltage, and the output end is connected with the analog / digital conversion pin of the digital single-chip microcomputer. A high-precision resistor R1 is used in the temperature acquisition circuit unit. One end of the high-precision resistor R1 is connected with a decoupling capacitor C1, and the other end is connected with a negative temperature coefficient thermistor Rntc. A current limiting resistor R2 is connected with a filter capacitor C2. As shown in Figure 5 , a negative temperature coefficient thermistor Rntc is selected as a temperature sensor in the scheme, with a precision of 1%. When designing the circuit board, it is placed close to the silicon photomultiplier, the purpose is to more accurately collect the temperature of the silicon photomultiplier, and provide accurate data support for the later voltage regulation process. A resistance-capacitance filter circuit is set in the circuit design, which can filter out the interference components in the signal, and improve the temperature measurement precision. The decoupling capacitor C1 can filter out the high-frequency components mixed in the power supply, to prevent interference from being transmitted to the later stage circuit. The current limiting resistor R2 and the filter capacitor C2 constitute a low-pass filter circuit, which can filter out the alternating components in the output signal of the temperature sensor. The filtered signal is directly sent to the A / D acquisition port of the digital single-chip microcomputer for temperature acquisition, which can make the temperature measurement more accurate.

[0049] The semiconductor detector has high stability requirement for supply voltage, and the noise and ripple in the power supply will reduce the performance of the semiconductor detector. The voltage generation circuit is used for providing a stable and reliable power supply for the silicon photomultiplier detector. The voltage generation circuit comprises Figure 6 and Figure 7 two parts. Figure 6 The first part is a boost circuit, the input end of the boost circuit is electrically connected with an external input voltage Vin, and the output end is electrically connected with the input end of the linear power supply step-down circuit. Since the external input voltage Vin is a 5V direct current voltage, and the normal working voltage of the silicon photomultiplier is about 30V, the first step is to increase the input 5V voltage to the working voltage of the silicon photomultiplier. The circuit selects a domestic high-efficiency boost chip SGM6601Y to increase the 5V voltage to 32V. R7 and R8 form an enable network and are connected with the fourth pin of the boost chip SGM6601Y. R9 and R10 form a voltage feedback network and are connected with the third pin of the boost chip SGM6601Y.

[0050] Figure 7 The second part is a linear power supply step-down circuit, the input end of the linear power supply step-down circuit is electrically connected with the output end of the boost circuit, and the output end is electrically connected with the silicon photomultiplier supply end and the input end of the voltage collection unit. The starting resistor R11 in the circuit is connected with the fifth pin of the high-voltage linear power supply chip TPS7A4901. R5 and R3 form a network feedback network and are connected with the second pin of the high-voltage linear power supply chip TPS7A4901. The advantage of using the linear power supply step-down is that the ripple and noise interference in the power supply can be greatly reduced. Figure 5 The output 32V voltage cannot be directly used to supply power to the silicon photomultiplier, because the voltage is obtained by boost through a switching power supply, and the internal contains the ripple consistent with the switching frequency, and also contains high-frequency noise. The advantage of the linear power supply chip is that it has a very high power supply rejection ratio, and the high-voltage linear power supply chip TPS7A4901 has a power supply rejection ratio of up to 72dB, which can block the transmission of the ripple and noise in the input power supply to the output end. Therefore, a stable and clean power supply can be obtained after the linear power supply step-down, which can be provided to the silicon photomultiplier.

[0051] The voltage regulation circuit unit is the focus of improvement in the utility model, and realizes the function of continuously adjustable output voltage. The input end of the voltage regulation circuit is electrically connected with the analog voltage output pin of the digital single-chip microcomputer, and the output end is electrically connected with the second pin of the high-voltage linear power supply chip TPS7A4901. Since the performance of the silicon photomultiplier is sensitive to the environmental temperature, when the environmental temperature changes, in order to maintain the consistency of the performance of the silicon photomultiplier, the silicon photomultiplier should be properly compensated to offset the change of the performance of the silicon photomultiplier caused by the change of the environmental temperature. The compensation is realized by adjusting the supply voltage. The circuit is as followsFigure 8 The circuit in the dashed box implements the adjustment of the output voltage. The voltage value at VFB is constant, 1.185V in this application, and the resistance R6 is a high-precision resistor, one end of which is electrically connected to the second pin of the high-voltage linear power supply chip TPS7A4901, and the other end is connected to the capacitor C4. The resistance value is determined according to the working voltage range of the silicon photomultiplier, which is designed as 132KΩ in this scheme. In this scheme, Vdac is connected to the analog voltage output pin of the digital single-chip microcomputer. The resistor R4 and the capacitor C4 constitute a resistance-capacitance low-pass filter, which is used to make the analog voltage output by the digital single-chip microcomputer more stable. Because the analog voltage output by the digital single-chip microcomputer is continuously adjustable, the voltage supplied to the silicon photomultiplier is also continuously adjustable.

[0052] The voltage adjustment process of this scheme is as follows:

[0053] 1. According to the specification of the silicon photomultiplier, two important data can be obtained. One is that when the ambient temperature is 25℃, the recommended working voltage of the silicon photomultiplier is 26.2V; the second is the breakdown voltage temperature coefficient of the silicon photomultiplier, which is 34.4mV / ℃ in this scheme, i.e. for every 1℃ change in ambient temperature, the supply voltage of the silicon photomultiplier needs to be compensated by 34.4mV to keep the performance of the silicon photomultiplier unchanged.

[0054] 2. Establish the initial condition of voltage regulation

[0055] When the analog voltage value output by the digital single-chip microcomputer is 1.185V, the voltage value output at this moment can be calculated according to formula 1, which is 26.2V, corresponding to the recommended working voltage of the silicon photomultiplier when the ambient temperature is 25℃.

[0056] 3. Dynamic voltage regulation process

[0057] The digital single-chip microcomputer collects the ambient temperature in real time through the temperature sensor, and then compares it with the initial temperature of 25℃. According to the temperature difference, the compensation voltage is calculated and converted into the analog voltage value output by the digital single-chip microcomputer. Formula 2 describes the relationship between the output voltage value and the ambient temperature, and formula 3 describes the calculation method of converting the compensation voltage into the analog voltage value output by the digital single-chip microcomputer. In the program code, the Vadc value is directly operated to realize continuous adjustment of the output voltage.

[0058]

[0059]

[0060] Vdacinit: the analog voltage value output by the single-chip microcomputer when the ambient temperature is 25℃, which is 1.185V in this scheme.

[0061] T: is the current collected ambient temperature, unit is ℃. k: temperature coefficient, the value in this scheme is 0.0344, that is 34.4 mV / ℃. Resistance R5 and resistance R6: for voltage feedback loop resistance, unit is KΩ.

[0062] Combining the above formula 2 and formula 3 can be calculated, when the voltage at Vdac is equal to 0V, the output voltage Vbias

[0063] Gets the maximum value, for 28.2V. When Vdac voltage is equal to 3.0V, the output voltage Vbias gets the minimum value, for 23.16V. Therefore the output voltage can be continuously adjusted between the maximum value and the minimum value, changing the value of resistance R5, R6 can change the adjustment range.

[0064] As Figure 9 , the input end of the voltage acquisition circuit unit is electrically connected with the output end of the voltage generation circuit unit, the output end is electrically connected with the analog-digital conversion pin of the digital single-chip microcomputer, and the resistance R12 and the resistance R13 are connected in series to form a voltage dividing network. This part of function is relatively simple, the digital single-chip microcomputer collects the output voltage value after adjustment, if the difference between the monitored voltage value and the theoretically calculated voltage value is greater than 20mV, the output voltage will be started to adjust.

[0065] The software control process adopted by the application is shown in Figure 10 The software control process is relatively simple, after the equipment is powered on, the software first initializes the temperature drift coefficient, and outputs the voltage according to the initial condition. Then the digital single-chip microcomputer collects the working environment temperature of the silicon photomultiplier in real time, then calculates the temperature difference, the voltage compensation value, and converts to the voltage of Vdac, then the digital single-chip microcomputer adjusts the analog voltage output, realizes the continuous adjustable output voltage.

[0066] The basic principle and main features of the utility model and the advantages of the utility model are shown and described. The various components mentioned in the utility model are common techniques in the prior art, which should be understood by those skilled in the art. The utility model is not limited by the above embodiments, and the above embodiments and descriptions in the specification are only to illustrate the principle of the utility model. Without departing from the spirit and scope of the utility model, the utility model will have various changes and improvements, and these changes and improvements all fall within the scope of the utility model claimed. The protection scope of the utility model is defined by the appended claims and their equivalents.

Claims

1. A circuit for outputting an autonomously continuously adjustable voltage, characterized in that The application relates to a voltage reference circuit unit, a temperature acquisition circuit unit, a voltage generation circuit unit, a voltage regulation circuit unit and a voltage acquisition circuit unit, wherein the output end of the voltage reference circuit unit is electrically connected with a reference voltage pin of a digital single-chip microcomputer, the input end of the temperature acquisition circuit unit is connected with a 3.3V voltage, the output end of the temperature acquisition circuit unit is connected with an analog / digital conversion pin of the digital single-chip microcomputer, the output end of the voltage regulation circuit unit is connected with the voltage generation circuit unit, the output end of the voltage generation circuit unit is connected with a power supply end of a silicon photomultiplier and the input end of the voltage acquisition circuit unit, and the output end of the voltage acquisition circuit unit is electrically connected with an analog / digital conversion pin of the digital single-chip microcomputer.

2. The circuit of claim 1, wherein The voltage reference circuit unit is composed of a reference source chip REF3030, a decoupling capacitor Cin and an energy storage capacitor Cout, the input end of the reference source chip REF3030 is electrically connected with a 3.3V voltage and the decoupling capacitor Cin respectively, and the output end of the reference source chip REF3030 is connected with the energy storage capacitor Cout and a reference voltage pin of the digital single-chip microcomputer respectively.

3. The circuit of claim 1, wherein The temperature acquisition circuit unit comprises a high-precision resistor R1, one end of the high-precision resistor R1 is connected with a 3.3V voltage and a decoupling capacitor C1 respectively, the other end of the high-precision resistor R1 is connected with a current-limiting resistor R2 and a thermistor Rntc respectively, and the current-limiting resistor R2 is connected with a filter capacitor C2 and an analog / digital conversion pin of the digital single-chip microcomputer respectively.

4. The circuit of claim 1, wherein The voltage generation circuit unit comprises a step-up circuit and a linear power supply step-down circuit, the input end of the step-up circuit is connected with a 5V input voltage, the output end of the step-up circuit is connected with the input end of the linear power supply step-down circuit, and the output end of the linear power supply step-down circuit is electrically connected with a power supply end of a silicon photomultiplier and the input end of a voltage acquisition unit respectively.

5. The circuit for outputting an autonomously continuously adjustable voltage according to claim 4, characterized in that The step-up circuit comprises a step-up chip SGM6601Y, the fifth pin of the step-up chip SGM6601Y is connected with a 5V input voltage and a capacitor C8, the fourth pin of the step-up chip SGM6601Y is connected with a resistor R7 and a resistor R8 respectively, the second pin of the step-up chip SGM6601Y is grounded, the first pin of the step-up chip SGM6601Y is connected with a capacitor C9, and the third pin of the step-up chip SGM6601Y is connected with a resistor R9 and a resistor R10 respectively.

6. The circuit for outputting an autonomously continuously adjustable voltage according to claim 5, characterized in that The linear power supply step-down circuit comprises a high-voltage linear power supply chip TPS7A4901, the fifth pin of the high-voltage linear power supply chip TPS7A4901 is connected with a starting resistor R11, the sixth pin of the high-voltage linear power supply chip TPS7A4901 is connected with a capacitor C11, the fourth pin of the high-voltage linear power supply chip TPS7A4901 is grounded, and the second pin of the high-voltage linear power supply chip TPS7A4901 is connected with a resistor R3 and a resistor R5 respectively.

7. The circuit for outputting an autonomously continuously adjustable voltage according to claim 6, characterized in that The voltage regulating circuit unit comprises a resistor R6, a resistor R4 and a capacitor C4, one end of the resistor R4 is electrically connected with an analog voltage output pin of the digital single-chip microcomputer, the other end of the resistor R4 is connected with the resistor R6 and the capacitor C4 respectively, and the resistor R6 is electrically connected with a second pin of a high-voltage linear power supply chip TPS7A4901.

8. The circuit of claim 1, wherein The voltage collecting circuit unit comprises a resistor R12, one end of the resistor R12 is connected with an output end of the voltage generating circuit and a capacitor C13 respectively, and the other end of the resistor R12 is connected with a resistor R13 in series.

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