Power supply circuit and electrical equipment

Abstract

The present invention discloses a power supply circuit and electrical equipment, relating to the field of circuit technology. The power supply circuit includes a primary winding circuit and multiple secondary winding circuits; the multiple secondary winding circuits include a first winding circuit; the first winding circuit includes a rectifier unit and a voltage stabilization unit. By providing a voltage stabilization unit in the first winding circuit of the secondary winding circuit of a transformer, the present invention can effectively reduce the impact of other secondary winding circuits on the first winding circuit, suppress voltage fluctuations, and improve output stability. Moreover, the circuit structure is simple, saving design costs.

Description

Technical Field

[0001] The present invention relates to the field of circuit technology, and in particular to a power supply circuit and electrical equipment. Background Art

[0002] Transformers are commonly used in power supply circuits. When a transformer has multiple secondary windings, the different secondary windings may interact with each other. For example, in a flyback power supply circuit, ideally, the voltages between its multiple secondary windings have a certain turns ratio. However, in practical applications, flyback power supply circuits often connect a larger load to the feedback winding than to the other non-feedback windings. This causes excessive energy to be generated in the non-feedback windings, resulting in a high output voltage, or excessive cross-regulation voltage. Under the influence of the cross-regulation voltage, the secondary windings of the transformer are prone to voltage drift, which may cause load device losses. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a power supply circuit with a simple structure, low design cost, and relatively stable output voltage, which is conducive to the normal operation of load devices.

[0004] The power supply circuit in an embodiment of the present invention includes a primary winding circuit and multiple secondary winding circuits; wherein the multiple secondary winding circuits include a first winding circuit; the first winding circuit includes a rectifier unit and a voltage stabilizing unit for reducing output voltage fluctuations of the first winding circuit; the rectifier unit is connected to the voltage stabilizing unit.

[0005] The power supply circuit in the embodiment of the present invention has at least the following beneficial effects:

[0006] In an embodiment of the present invention, a voltage stabilizing unit is provided in the first winding circuit in the secondary winding circuit of the transformer, which can effectively improve the influence of other secondary winding circuits on the first winding circuit, suppress the fluctuation of the output voltage of the first winding circuit, and improve its output stability; moreover, the circuit structure in the embodiment of the present invention is simple, which can greatly save manufacturing costs and improve efficiency.

[0007] In an embodiment of the present invention, the voltage stabilizing unit includes a first resistor, a second resistor and a reference voltage chip; one end of the first resistor is connected to the feedback end of the reference voltage chip; the other end of the first resistor, the anode end of the reference voltage chip and the second end of the rectifier unit are grounded; one end of the second resistor is connected to the first end of the rectifier unit, and the other end of the second resistor is connected to the feedback end of the reference voltage chip; the cathode end of the reference voltage chip is connected to the first end of the rectifier unit.

[0008] In an embodiment of the present invention, the voltage stabilizing unit further includes a protection resistor; the protection resistor is provided on a line connecting the cathode end of the reference voltage chip and the first end of the rectifier unit.

[0009] In the embodiment of the present invention, the protection resistor can prevent a large current from flowing into the cathode terminal of the reference voltage chip, thereby protecting the reference voltage chip.

[0010] In an embodiment of the present invention, the first winding circuit further includes an absorption unit; a first end of the absorption unit is connected to the first input end of the voltage stabilizing unit; and a second end of the absorption unit and a second end of the rectifying unit are grounded.

[0011] In the embodiment of the present invention, the absorption unit can absorb the high voltage of the first winding circuit.

[0012] In an embodiment of the present invention, the absorption unit includes an absorption load; the absorption load includes a combination of at least one or more of a resistor, an LED lamp, or an LCD screen.

[0013] In the embodiment of the present invention, different loads can increase the absorption efficiency of the absorption unit and make the power supply circuit stabilize more quickly.

[0014] In an embodiment of the present invention, the first winding circuit also includes a shunt unit; the shunt unit includes a fourth resistor, a fifth resistor and a transistor; one end of the fourth resistor is connected to the base of the transistor and the cathode end of the reference voltage chip; the other end of the fourth resistor is connected to the first end of the rectifier unit; the collector of the transistor is connected to the first end of the rectifier unit, the emitter of the transistor is connected to one end of the fifth resistor, and the other end of the fifth resistor is grounded.

[0015] In the embodiment of the present invention, the shunt unit can not only shunt the voltage flowing through the cathode of the reference voltage chip, but also further consume the energy generated by the voltage drift.

[0016] In an embodiment of the present invention, the first winding circuit also includes a shunt unit; the shunt unit includes a fourth resistor, a fifth resistor and a transistor; one end of the fourth resistor is connected to the base of the transistor and the cathode end of the reference voltage chip; the other end of the fourth resistor is connected to the first end of the rectifier unit; the collector of the transistor is connected to the first end of the rectifier unit, the emitter of the transistor is connected to one end of the fifth resistor, and the other end of the fifth resistor is grounded.

[0017] Similarly, in the embodiment of the present invention, the shunt unit can further consume the energy generated by the voltage drift.

[0018] In the embodiment of the present invention, the second resistor is an adjustable resistor.

[0019] In the embodiment of the present invention, the adjustable resistor can facilitate relevant personnel to adjust the output voltage of the first winding circuit as needed, thereby avoiding repeated replacement of the resistor when the circuit is used and improving the use efficiency.

[0020] In an embodiment of the present invention, the rectifier unit includes a diode and a capacitor; the rectifier unit is used to convert alternating current into direct current.

[0021] In the embodiment of the present invention, the rectifier unit can convert AC power into DC power by utilizing the reverse cutoff function of the diode and the charge and discharge function of the capacitor. In addition, in the embodiment of the present invention, the capacitor is an electrolytic capacitor, which can store more energy.

[0022] In an embodiment of the present invention, the multiple secondary winding circuits further include a feedback winding circuit; the feedback winding circuit includes an optocoupler; and the optocoupler is used to electrically isolate the primary winding circuit from the secondary winding circuit.

[0023] In the embodiment of the present invention, the feedback winding circuit can control the driving chip of the primary winding circuit to output pulses with different duty cycles, thereby changing the magnetic flux of the primary winding circuit.

[0024] In an embodiment of the present invention, the primary winding circuit includes a rectifier module, a boost module and a switching power supply module; the rectifier module is connected to the boost module; and the boost module is connected to the switching power supply module.

[0025] In the embodiment of the present invention, the primary winding circuit can provide energy for the secondary winding circuit, and the switching power supply module can invert the direct current processed by the rectifier module and the boost module into alternating current.

[0026] An electrical device according to an embodiment of the second aspect of the present invention includes the power supply circuit described in the above embodiment.

[0027] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention.

[0028] The electrical device according to the embodiment of the present invention has at least the following beneficial effects:

[0029] In embodiments of the present invention, the power supply circuit, by adding a voltage stabilizing unit to the first winding circuit, can effectively mitigate the impact of other secondary winding circuits on the output voltage of the first winding circuit, thereby improving the voltage stability of the first winding circuit, making the operation of the electrical equipment more stable and reliable, and extending the service life of the electrical equipment. Furthermore, this circuit has a simple structure, saving design costs for the electrical equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0031] Figure 1 A schematic diagram of the circuit structure of a power supply circuit embodiment of the present invention;

[0032] Figure 2 A schematic diagram of the position of a protective resistor and its circuit structure in an embodiment of a power supply circuit of the present invention;

[0033] Figure 3 Schematic diagram of the position and circuit structure of a shunt circuit in another embodiment of a power supply circuit of the present invention;

[0034] Figure 4 Schematic diagram of the absorption circuit position and circuit structure in another power supply circuit embodiment of the present invention. DETAILED DESCRIPTION

[0035] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0036] In the description of the present invention, it should be understood that descriptions involving orientation, such as the orientation or positional relationship indicated by up, down, etc., are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0037] In the description of the present invention, "a plurality" refers to more than two. The use of "first" or "second" is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of the indicated technical features, or implicitly indicating the order of the indicated technical features.

[0038] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0039] In the technical field of power supply circuits, power supply circuits are generally categorized by type and characteristics, including switching power supply circuits, voltage-regulated power supply circuits, current-regulated power supply circuits, and power supply circuits. Within power supply circuits, transformers are often used to step up or down the circuit voltage, ensuring that the output voltage reaches a specified level for various electrical devices. Transformers typically have a primary winding circuit and a secondary winding circuit. The transformer can step up or down the voltage based on the number of turns in the primary and secondary winding circuits. In some cases, the power supply circuit may need to output power at multiple voltage levels, so multiple secondary winding circuits may be provided. Ideally, the output voltage of each secondary winding circuit is directly proportional to the number of turns in its coil. If each secondary winding circuit is unloaded or in an ideal state, there is no mutual influence between the secondary winding circuits. However, because multiple secondary winding circuits may have different load voltages or are affected by factors such as leakage inductance, cross-regulation voltages are easily generated in multiple secondary winding circuits during voltage changes. This cross-regulation voltage varies depending on the circuit load and can result in either an increased voltage drift or a decreased voltage. The degree of influence between secondary winding circuits can be measured by the cross-regulation rate. For example, if the voltage of one secondary winding circuit changes by 1V, the voltage of the other secondary winding circuit fluctuates by 0.1V due to the change. The cross-regulation rate of the two secondary winding circuits can be determined to be 10%. It is understood that the higher the cross-regulation rate, the more unstable the output of the secondary winding circuit. When the voltage drift exceeds a certain level, it can easily cause power loss in the load components. Excessive voltage drift can also burn out the load components, shortening the service life of the circuit and equipment. Therefore, there is an urgent need to improve the power supply circuit in the related art.

[0040] In an embodiment of the present invention, a power supply circuit is provided. The power supply circuit includes a primary winding circuit and multiple secondary winding circuits. The primary winding circuit and the secondary winding circuit are embedded in the same magnetic core, ensuring that the changing magnetic flux in the primary winding circuit can be transmitted to the secondary winding circuit, reducing the risk of leakage inductance. The changing magnetic flux in the primary winding circuit can affect the voltage of the secondary winding circuit. Specifically, in some embodiments of the present invention, the primary winding circuit may include a rectifier module, a boost module, and a switching power supply module. The rectifier module is electrically connected to the boost module; the switching power supply module is connected to the boost module via a circuit. The primary winding circuit can be powered by the mains and the voltage of the power supply can be adjusted accordingly. For example, the rectifier module can rectify the mains or other AC power into a DC voltage, and the boost module can boost the rectified voltage to a desired voltage level. The switching power supply module can convert the DC voltage rectified by the rectifier module and boosted by the boost module into an AC voltage. A driver IC can be installed within the switching power supply module. This driver IC can change the magnetic flux of the primary winding circuit by varying the duty cycle of the output pulses. Multiple secondary winding circuits can generate an induced voltage based on the changing magnetic flux in the primary winding circuit, which can serve as the output voltage of the secondary winding circuit. Specifically, the primary winding circuit of the entire power supply circuit converts AC power into DC power through a rectifier module. The switching power supply module inverts the DC power into AC power. The AC power of the primary winding circuit is converted into AC power for the first winding circuit and other secondary winding circuits through the action of the windings and magnetic core, thereby powering other devices.

[0041] In an embodiment of the present invention, the structure of the secondary winding circuit of the power supply circuit is improved. The improvement here can be an improvement to one or more secondary winding circuits. For the convenience of description, one of the improved secondary winding circuits is used as an example for explanation, and the secondary winding circuit is recorded as the first winding circuit. It can be understood that in the embodiment of the present invention, the secondary winding circuit can include any number of first winding circuits; it can also be a first winding circuit and other winding circuits; wherein the other secondary winding circuits can be a secondary winding circuit for auxiliary output, or a feedback winding circuit for controlling the primary winding circuit according to a feedback signal. Specifically, in some embodiments of the present invention, the feedback winding circuit is connected in such a way that the winding portion of the feedback winding circuit is set on the secondary side, and its feedback portion uses a combination circuit of an optocoupler and a TL431 chip to isolate the primary winding circuit from the secondary winding circuit.

[0042] The first winding circuit in the embodiment of the present invention is described below with reference to the accompanying drawings.

[0043] Reference Figure 1In an embodiment of the present invention, the circuit containing windings 1 and 2 is the secondary winding circuit, and the circuit containing windings 3 and 4 is the primary winding circuit. For ease of explanation, in this embodiment of the present invention, the secondary winding circuit containing winding 1 is referred to as the first winding circuit, and the secondary winding circuit containing winding 2 is referred to as the feedback winding circuit. The first winding circuit may include a rectifier unit and a voltage stabilization unit. The rectifier unit may include winding 1, a diode D1, and a capacitor C1. In this embodiment of the present invention, winding 1 may have different turns depending on the output voltage. Capacitor C1 may be an electrolytic capacitor, which can store more energy than ordinary capacitors, improving the stability of the rectifier unit. The electrolytic capacitor can store the electrical energy generated by winding 1 during the positive half-cycle and release it during the negative half-cycle. The anode of diode D1 is connected to the first winding, the cathode is connected to the positive electrode of capacitor C1, and the negative electrode of capacitor C1 is grounded. The rectifier unit can rectify the AC power with positive and negative half-cycles output from the winding port in the first winding circuit into a DC output. In some embodiments, the voltage stabilizing unit may include a first resistor R1, a second resistor R2, and a reference voltage chip U1; wherein one end of the first resistor R1 is connected to the feedback end of the reference voltage chip U1; the other end of the first resistor R1, the anode end of the reference voltage chip U1, and the second end of the rectifier unit are grounded; one end of the second resistor R2 is connected to the first end of the rectifier unit; the other end of the second resistor R2 is connected to the feedback end of the reference voltage chip U1; and the cathode end of the reference voltage chip U1 is connected to the first end of the rectifier unit. In this embodiment, the reference voltage chip U1 may be a TL431 chip. When the first winding circuit is affected by other secondary winding circuits, causing the voltage output of the rectifier unit to drift high, if the first winding circuit is directly connected to the load device after rectification, the drifted voltage will cause significant loss to the load device, potentially affecting the normal operation of the circuit. In this embodiment, the voltage stabilizing unit can be arranged between the rectifier unit and the applied load device. The reference voltage chip U1 of the voltage stabilizing unit has a fixed potential at the feedback terminal relative to ground due to the internal reference voltage. For example, the potential of the feedback terminal of the reference voltage chip U1 relative to ground is 2.5V, that is, the voltage across the first resistor R1 is stable at 2.5V. The first resistor R1 and the second resistor R2 are connected to ground in series. Therefore, the output voltage of the entire voltage stabilizing unit is ultimately determined by the ratio of the first resistor R1 to the second resistor R2. Specifically, for example, when the resistance value of the first resistor R1 is 5K ohms and the resistance value of the second resistor R2 is 15K ohms, the ratio of the resistance value of the first resistor R1 to the resistance value of the second resistor R2 is 1:3. According to the characteristics of the series circuit, the voltage drop ratio is also 1:3. The regulated output of the voltage stabilizing unit depends on the sum of the voltage drops of the first resistor R1 and the second resistor R2. Therefore, the output voltage of the voltage stabilizing unit is 4 times the reference voltage, that is, 10V.Of course, in some embodiments of the present invention, the resistance of the second resistor can also be 0, that is, the feedback end of the reference voltage chip U1 can be directly short-circuited with the cathode. At this time, the output of the voltage stabilizing unit will be directly stabilized at 2.5V, which is the same as the reference voltage inside the reference voltage chip U1. In order to facilitate the dynamic adjustment of the voltage stabilizing unit so that it can adapt to different output requirements, reduce the tedious operation of constantly replacing resistors in actual applications, and improve the operating efficiency of the circuit, optionally, in some embodiments of the present invention, the second resistor R2 can also be selected to adopt an adjustable resistor. The resistance adjustment range of the adjustable resistor can be set according to different voltage requirements. When in use, by adjusting the ratio of the first resistor R1 and the second resistor R2, the voltage value required by the voltage stabilizing unit output can be controlled, and the stable range is smaller, further improving the accuracy of the stable voltage. The specific circuit principle is similar to the above and will not be repeated here.

[0044] Optionally, in an embodiment of the present invention, a reference voltage chip U1 is used for voltage stabilization output. As mentioned above, the chip model may be TL431, which includes an operational amplifier and a transistor. When the output current of the first winding circuit increases, if there is no load on the line between the rectifier unit and the reference voltage chip TL431, a large current flows into the reference voltage chip U1 through the branch, which may cause the reference voltage chip U1 to be broken down and burned. Therefore, in order to protect the reference voltage chip U1 and adapt it to the voltage stabilization requirements of a larger current range, in some embodiments, the first winding circuit in the embodiment of the present invention may also include a protection resistor R3. The specific connection method of the protection resistor R3 can be referred to. Figure 2 . Specifically, the protection resistor R3 can be set on the line connecting the cathode of the reference voltage chip U1 and the rectifier unit. In this way, when a large current passes through the line connected to the rectifier unit and the cathode of the reference voltage chip U1, the protection resistor R3 can effectively limit the current flowing to the cathode of the reference voltage chip U1, reducing the risk of the reference voltage chip U1 being burned out. Due to the presence of the protection resistor R3, the entire voltage stabilizing circuit can also adapt to a larger current input, thereby increasing the current range available for the entire voltage stabilizing unit and improving the applicability of the power supply circuit. It should be noted that due to the characteristics of the TL431 chip itself, in order to maintain the stability of the internal reference voltage of the chip and ensure that the voltage drop of the first resistor R1 is 2.5V, the current passing through its feedback end needs to be maintained at a certain value, for example, the current needs to be greater than 1uA. Therefore, in this application, the resistance value of the protection resistor R3 can be set within a certain range so that the current passing through the cathode of the reference voltage chip U1 meets the above requirements.

[0045] Optionally, in order to adapt to the output of a larger current, in some embodiments of the present invention, the first winding circuit may further be provided with a shunt unit after the voltage stabilizing unit. Figure 3 ,exist Figure 3 The shunt unit in the circuit includes a fourth resistor R4, a fifth resistor R5 and a transistor Q1. The transistor Q1 can be an NPN transistor. In some embodiments, the transistor can also be a PNP transistor. One end of the fourth resistor R4 is connected to the first end of the rectifier unit, and the other end of the fourth resistor R4 is connected to the base of the transistor Q1 and the cathode of the reference voltage chip U1. One end of the fifth resistor R5 is connected to the emitter of the transistor Q1, and the other end of the fifth resistor R5 and the second end of the rectifier unit are grounded together, while the collector of the transistor Q1 is connected to the first end of the rectifier unit. Figure 3 In the illustrated shunt unit, the fourth resistor R4 shares the current flowing to the voltage stabilizing unit while also protecting transistor Q1 from excessive current that could cause breakdown. The fifth resistor R5 dissipates energy generated by the voltage drift in the first winding circuit, preventing excessive energy from being applied to the voltage stabilizing unit and causing abnormal heating, thereby improving the unit's practicality and service life. When the larger current output by the rectifier unit passes through the branch where the cathode of the reference voltage chip U1 is located, since the input end of the shunt module is connected to the line node between the protection resistor R3 and the output end of the rectifier unit, according to Kirchhoff's law of the circuit, the larger current will flow to the branch where the protection resistor R3 is located and the branch where the fourth resistor R4 is located, respectively. Under the action of the current, the voltage stabilizing unit operates normally, and the voltage output by the voltage stabilizing unit will turn on the base of the transistor Q1. After the base of the transistor Q1 is turned on, the branches where the emitter and collector are located are also turned on. The fifth resistor R5 in the branch where the emitter is located can absorb the energy generated by the voltage drift to further stabilize the output voltage of the first winding circuit. Further optionally, in the embodiment of the present invention, the fifth resistor R5 can also be replaced with other load-carrying devices or modules, or a combination of resistors and LEDs.

[0046] In addition, in the embodiment of the present invention, the first winding circuit may further include an absorption unit, which may be composed of three parallel absorption loads and a load control module. The absorption load may be a static load such as a resistor. The circuit reference Figure 4 ,exist Figure 4In the embodiment, the absorption load includes a plurality of field-effect transistors (FETs) and resistors, including a first FET K1, a second FET K2, a third FET K3, a first absorption resistor RS1, a second absorption resistor RS2, and a third absorption resistor RS3. The gate of each FET is connected to a load control module, which can selectively turn on or off loads of different numbers or branches based on changes in the output voltage of the first winding. Optionally, in this absorption unit, the FET functions to control the conduction or shutdown of the branch where the absorption load is located. Therefore, in some embodiments, the FET can also be replaced with a commonly used NPN or PNP transistor. Specifically, when the first winding circuit is affected by other secondary winding circuits, causing the output voltage of the first winding circuit to drift high, the load control module detects that the output voltage of the first winding circuit is greater than a threshold value. The load control module sends an electrical signal to control the first field-effect transistor K1 to conduct. The resistance RS1 of the absorbing load can absorb the drifting voltage to keep the output voltage of the first winding voltage within the threshold range. If the branch where the first field-effect transistor K1 is located still cannot eliminate the drifting high voltage of the first winding voltage, the load control module can send an electrical signal to control the second field-effect transistor K2 and the third field-effect transistor K3 to conduct. Through the absorption effect of multiple branches, the first winding voltage is maintained stable. Moreover, the multi-branch design can also make the first winding circuit adaptable to more loads or devices with different power. It is understood that in the embodiment of the present invention, the absorbing load is not limited to three and can also be more absorbing loads. In addition, since the absorption unit has multiple branches, when the first field-effect transistor K1, the second field-effect transistor K2, and the third field-effect transistor K3 are turned on, and the load control module detects that the output voltage of the first winding circuit is less than a threshold value, the load control module can control the closure of any branch of the first field-effect transistor K1, the second field-effect transistor K2, or the third field-effect transistor. If the voltage of the first winding circuit is still higher than the threshold value after one branch is closed, the load control module can also control the closure of the branch containing another field-effect transistor, thereby stabilizing the voltage of the first winding circuit within the threshold range. Optionally, in an embodiment of the present invention, the resistors of each branch of the absorption load can also be selected from resistors of different resistance values, further optimizing the absorption efficiency by taking advantage of the difference in absorption capacity of different resistance values. Alternatively, an adjustable resistor can be directly selected on a single branch, and the absorption efficiency of the branch can be adjusted by switching the adjustable resistor to different resistance values. Further optionally, in an embodiment of the present invention, the absorption load can also be a dynamic absorption load such as an LED or LCD screen. By adjusting the power of the dynamic absorption load, the absorption unit's efficiency in absorbing the high voltage output of the first winding circuit and its energy is accelerated. Moreover, the embodiment of the present invention combines the advantages of the absorption unit, the voltage stabilizing unit and the shunt unit, so that the embodiment of the present invention has a wider adaptability to voltage and current, can adapt to a variety of switching power supply circuits with different electrical parameters, meet the requirements of relevant personnel for improvement of cross-adjustment voltage, and further improve the practicality of the present invention.

[0047] The present application also provides an electrical device. The electrical device includes at least one or more power supply circuits of the above-mentioned embodiments; the power supply circuit includes a primary winding circuit and multiple secondary winding circuits; wherein the multiple secondary winding circuits include a first winding circuit; the first winding circuit includes a rectifier unit and a voltage stabilizing unit; the voltage stabilizing unit includes a first resistor, a second resistor, and a reference voltage chip; one end of the first resistor is connected to the feedback end of the reference voltage chip; the other end of the first resistor, the anode end of the reference voltage chip, and the second end of the rectifier unit are grounded; one end of the second resistor is connected to the first end of the rectifier unit, and the other end of the second resistor is connected to the feedback end of the reference voltage chip; the cathode end of the reference voltage chip is connected to the first end of the rectifier unit.

[0048] It can be understood that, since the electrical equipment adopts all the technical solutions of the power supply circuit of the above embodiment, it has at least all the beneficial effects brought by the technical solutions of the above embodiment, which will not be repeated here.

[0049] In summary, the present invention, as a power supply circuit and electrical equipment, has the following advantages:

[0050] (1) Good stability. The present invention adds a voltage stabilizing unit to the first winding circuit. The voltage stabilizing effect of the voltage stabilizing unit improves the influence of other secondary winding circuits on the first winding circuit, reduces the fluctuation of the output voltage of the first winding circuit, and improves the stability of the output of the first winding circuit.

[0051] (2) Simple structure and low cost. The power supply circuit in the embodiment of the present invention mostly uses basic components such as resistors and capacitors, and has low structural complexity, which can greatly reduce manufacturing costs and improve efficiency.

[0052] (3) The first winding circuit includes an absorption unit, which has good suppression performance for high-voltage drift.

[0053] (4) The absorption unit adopts different absorption loads and has faster absorption efficiency.

[0054] (5) The voltage application range is wide, and it can suppress output circuits in different voltage ranges.

[0055] (6) The first winding circuit includes a shunt unit that can adapt to the input and output of large currents.

[0056] In the above description of this specification, reference to the terms "one embodiment / example," "another embodiment / example," or "certain embodiments / examples" 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 present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples.

[0057] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and intent of the present application, and that the scope of the present application is defined by the claims and their equivalents.

[0058] The above is a specific description of the preferred implementation of the present application, but the present application is not limited to the embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present application, and these equivalent modifications or substitutions are all included in the scope defined by the claims of the present application.

Claims

1. A power supply circuit, characterized in that: The device comprises a primary winding circuit and a plurality of secondary winding circuits; wherein the plurality of secondary winding circuits include a first winding circuit; The first winding circuit includes a rectifier unit, a shunt unit and a voltage stabilizing unit for reducing output voltage fluctuations of the first winding circuit. The rectifier unit and the shunt unit are connected to the voltage stabilizing unit; the shunt unit includes a fourth resistor, an energy-consuming device and a transistor; one end of the fourth resistor is connected to the base of the transistor; one end of the fourth resistor is also connected to the voltage stabilizing unit; the other end of the fourth resistor is connected to the first end of the rectifier unit; the collector of the transistor is connected to the first end of the rectifier unit, the emitter of the transistor is connected to the other end of the energy-consuming device, and the other end of the energy-consuming device is grounded; wherein the energy-consuming device is a resistive device.

2. A power supply circuit according to claim 1, characterized in that: The voltage stabilizing unit includes a first resistor, a second resistor and a reference voltage chip; one end of the first resistor is connected to the feedback end of the reference voltage chip; the other end of the first resistor, the anode end of the reference voltage chip and the second end of the rectifier unit are grounded; one end of the second resistor is connected to the first end of the rectifier unit, and the other end of the second resistor is connected to the feedback end of the reference voltage chip; the cathode end of the reference voltage chip is connected to the first end of the rectifier unit.

3. A power supply circuit according to claim 2, characterized in that: The voltage stabilizing unit further includes a protection resistor; the protection resistor is arranged on a circuit connecting the cathode end of the reference voltage chip and the first end of the rectifier unit.

4. A power supply circuit according to any one of claims 2 or 3, characterized in that: The first winding circuit further includes an absorption unit; a first end of the absorption unit is connected to the first input end of the rectification unit; and a second end of the absorption unit is connected to the second end of the rectification unit.

5. A power supply circuit according to claim 4, characterized in that: The absorption unit includes an absorption load; the absorption load includes a combination of at least one or more of a resistor, an LED lamp, or an LCD screen.

6. A power supply circuit according to claim 1, characterized in that: The first winding circuit also includes a shunt unit; the shunt unit includes a fourth resistor, a fifth resistor and a transistor; one end of the fourth resistor is connected to the base of the transistor; one end of the fourth resistor is also connected to the cathode end of the reference voltage chip; the other end of the fourth resistor is connected to the first end of the rectifier unit; the collector of the transistor is connected to the first end of the rectifier unit, the emitter of the transistor is connected to one end of the fifth resistor, and the other end of the fifth resistor is grounded.

7. A power supply circuit according to claim 4, characterized in that: The first winding circuit also includes a shunt unit; the shunt unit includes a fourth resistor, a fifth resistor and a transistor; one end of the fourth resistor is connected to the base of the transistor; one end of the fourth resistor is also connected to the cathode end of the reference voltage chip; the other end of the fourth resistor is connected to the first end of the rectifier unit; the collector of the transistor is connected to the first end of the rectifier unit, the emitter of the transistor is connected to one end of the fifth resistor, and the other end of the fifth resistor is grounded.

8. A power supply circuit according to claim 2, characterized in that: The second resistor is an adjustable resistor.

9. The power supply circuit according to claim 1, characterized in that: The rectifying unit includes a diode and a capacitor.

10. The power supply circuit according to claim 1, characterized in that: The multiple secondary winding circuits also include a feedback winding circuit; the feedback winding circuit includes an optocoupler; the optocoupler is used to electrically isolate the primary winding circuit and the secondary winding circuit.

11. The power supply circuit according to claim 1, characterized in that: The primary winding circuit includes a rectifier module, a boost module and a switching power supply module; the rectifier module is connected to the boost module; and the boost module is connected to the switching power supply module.

12. An electrical device, characterized in that: The method comprises the power supply circuit according to any one of claims 1 to 11.

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