CN215072152U

CN215072152U - Power supply circuit and electrical equipment

Info

Publication number: CN215072152U
Application number: CN202121490213.9U
Authority: CN
Inventors: 王慧锋; 钟雄斌; 徐锦清
Original assignee: GD Midea Air Conditioning Equipment Co Ltd; Foshan Shunde Midea Electric Science and Technology Co Ltd
Current assignee: GD Midea Air Conditioning Equipment Co Ltd; Foshan Shunde Midea Electric Science and Technology Co Ltd
Priority date: 2021-06-30
Filing date: 2021-06-30
Publication date: 2021-12-07
Anticipated expiration: 2031-06-30

Abstract

The utility model discloses a power supply circuit and electrical equipment, relating to the technical field of circuits, wherein the power supply circuit comprises a primary side winding circuit and a plurality of secondary side winding circuits; the plurality of secondary winding circuits comprise a first winding circuit; the first winding circuit comprises a rectifying unit and a voltage stabilizing unit. The utility model discloses a first winding circuit in the secondary winding circuit of transformer sets up the steady voltage unit, can effectively improve other secondary winding circuits to the influence of first winding circuit, and the fluctuation of suppression voltage improves the stability of output, and this circuit structure is simple moreover, has practiced thrift design cost.

Description

Power supply circuit and electrical equipment

Technical Field

The utility model relates to the technical field of circuits, in particular to power supply circuit and electrical equipment.

Background

In a power circuit, a transformer is a common device, and when there are multiple secondary winding circuits in the transformer, there may be mutual influence between different secondary winding circuits, for example: for a flyback power supply circuit, under an ideal condition, the voltages between a plurality of secondary winding circuits of the flyback power supply circuit are in a certain turn ratio relationship, but in practical application, the flyback power supply circuit is often connected to a load larger than that of other non-feedback winding circuits in a feedback winding circuit, so that excessive energy is generated in the non-feedback winding circuits, and a condition that the output voltage is too high occurs, that is, an excessively high cross regulation voltage is generated. Under the influence of cross regulation voltage, the secondary winding circuit in the transformer is easy to have the problem of high voltage drift, and the loss of a load device can be caused.

SUMMERY OF THE UTILITY MODEL

The utility model discloses aim at solving one of the technical problem that exists among the prior art at least. Therefore, the utility model provides a power supply circuit, this circuit's simple structure, design cost is lower, and output voltage is comparatively stable, is favorable to the normal work of load device.

The power circuit in the embodiment of the utility model comprises a primary winding circuit and a plurality of secondary winding circuits; the secondary winding circuits comprise a first winding circuit; the first winding circuit comprises a rectifying unit and a voltage stabilizing unit used for reducing the fluctuation of the output voltage of the first winding circuit, and the rectifying unit is connected with the voltage stabilizing unit.

The embodiment of the utility model provides an in power supply circuit has following beneficial effect at least:

in the embodiment of the utility model, the voltage stabilizing unit is arranged 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, inhibit the fluctuation of the output voltage of the first winding circuit and improve the output stability; moreover, the embodiment of the utility model provides an in circuit structure is simple, can practice thrift manufacturing cost greatly, the benefit is improved.

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 with 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 rectifying unit are grounded; one end of the second resistor is connected with the first end of the rectifying unit, and the other end of the second resistor is connected with the feedback end of the reference voltage chip; and the cathode end of the reference voltage chip is connected with the first end of the rectifying unit.

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

The embodiment of the utility model provides an in, the protection resistance can avoid the heavy current to flow into the negative pole end of reference voltage chip, has protected the reference voltage chip.

In an embodiment of the present invention, the first winding circuit further includes an absorption unit; the first end of the absorption unit is connected with the first input end of the voltage stabilizing unit; the second end of the absorption unit and the second end of the rectification unit are grounded.

In the embodiment of the utility model provides an in, the voltage that first winding circuit floats can be absorbed to the absorption unit.

In an embodiment of the present invention, the absorption unit includes an absorption load; the absorptive load comprises at least one or a combination of more of a resistor, an LED light, or an LCD screen.

The embodiment of the utility model provides an in, different loads can accelerate the absorption efficiency of absorption unit, make power supply circuit tend to stably more fast.

In an embodiment of the present invention, the first winding circuit further includes a shunt unit; the shunt unit comprises a fourth resistor, a fifth resistor and a triode; one end of the fourth resistor is connected with the base electrode of the triode and the cathode end of the reference voltage chip; the other end of the fourth resistor is connected with the first end of the rectifying unit; and the collector of the triode is connected to the first end of the rectifying unit, the emitter of the triode is connected with one end of the fifth resistor, and the other end of the fifth resistor is grounded.

The embodiment of the utility model provides an in, reposition of redundant personnel unit not only can shunt the voltage that flows through the negative pole of reference voltage chip, can further consume the energy that the voltage floats high production moreover.

Similarly, in the embodiment of the present invention, the shunting unit may further consume the energy generated by the voltage drift.

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

The embodiment of the utility model provides an in, adjustable resistance can be convenient for relevant personnel adjust the output voltage of first winding circuit as required. Repeated resistor replacement during circuit use is avoided, and the use efficiency is improved.

In an embodiment of the present invention, the rectifying unit includes a diode and a capacitor; the rectifying unit is used for converting alternating current into direct current.

The embodiment of the utility model provides an in, the rectifier unit can utilize the reverse function of ending of diode and the charge-discharge function of electric capacity to trun into the alternating current into the direct current, moreover the embodiment of the utility model provides an in, electric capacity adopts electrolytic capacitor, and electrolytic capacitor can save bigger energy.

In the embodiment of the present invention, the plurality of secondary winding circuits further include a feedback winding circuit; the feedback winding circuit comprises an optical coupler; the optical coupler is used for electrically isolating the primary winding circuit and the secondary winding circuit.

The embodiment of the utility model provides an in, the drive chip that feedback winding circuit can control primary winding circuit exports the pulse of different duty cycles, and then changes primary winding circuit's magnetic flux.

In the embodiment of the utility model, the primary winding circuit comprises a rectifier module, a boost module and a switch power supply module; the rectifying module is connected with the boosting module; the boosting module is connected with the switching power supply module.

The embodiment of the utility model provides an in, primary side winding circuit can provide the energy for secondary side winding circuit, and switching power supply module can be the alternating current with the direct current contravariant after rectifier module and the module processing that steps up.

According to the electric equipment of the second aspect of the invention, the power circuit comprises the power circuit of the above embodiment.

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

According to the utility model discloses electrical equipment has following beneficial effect at least:

the embodiment of the utility model provides an in, power supply circuit can effectively improve other secondary winding circuit to the output voltage's of first winding circuit influence through increase steady voltage unit in first winding circuit, has improved the voltage stability of first winding circuit, makes electrical equipment's operation more reliable and more stable, can improve electrical equipment's life. And this circuit structure is simple, has practiced thrift electrical equipment's design cost.

Drawings

The invention will be further described with reference to the following drawings and examples, in which:

fig. 1 is a schematic diagram of a circuit structure in an embodiment of a power circuit of the present invention;

fig. 2 is a schematic diagram of the position of a protection resistor and the circuit structure thereof in an embodiment of the power circuit of the present invention;

fig. 3 is a schematic diagram of the position of a shunt circuit and the circuit structure thereof in another embodiment of the power circuit of the present invention;

fig. 4 is a schematic diagram of an absorption circuit position and a circuit structure thereof in another embodiment of the power circuit of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the description of the orientation, such as the upper and lower directions, is the orientation or positional relationship shown on the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore should not be construed as limiting the present invention.

In the description of the present invention, a plurality means two or more. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless there is an explicit limitation, the words such as setting, installation, connection, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in combination with the specific contents of the technical solution.

In the field of power supply circuit technology, power supply circuits such as switching power supply circuits, voltage-stabilized power supply circuits, current-stabilized power supply circuits, and power supply circuits are generally classified according to different types and characteristics. In the power circuit, a transformer is commonly used to boost or buck the voltage of the circuit, so that the output voltage reaches a specified limit for various electrical appliances. For a transformer, which generally has a primary winding circuit and a secondary winding circuit, the transformer can increase or decrease the voltage according to the number of winding turns of the primary winding circuit and the secondary winding circuit. In some cases, the power circuit may be required to output power of multiple voltage levels, so that multiple secondary winding circuits may be provided. Under ideal conditions, the output voltage of each secondary winding circuit is in direct proportion to the number of turns of the coil of the secondary winding circuit, if each secondary winding circuit is in no-load or in an ideal state, the secondary winding circuits do not have mutual influence, but because a plurality of secondary winding circuits may have different load voltages or because of the influence of factors such as leakage inductance and the like, the plurality of secondary winding circuits are easy to generate cross regulation voltage in the process of voltage change, and the cross regulation voltage is different according to different circuit loads, and can be voltage drift high or voltage reduction. The influence degree between the secondary winding circuits can be measured by a cross regulation rate, for example, when the voltage of one secondary winding circuit changes by 1V and the voltage of the other secondary winding circuit affected by the voltage fluctuates by 0.1V, the cross regulation rate of the two secondary winding circuits can be determined to be 10%. It can be understood that the higher the cross regulation rate is, the more unstable the output of the secondary winding circuit is, when the voltage drift is high to a certain extent, the loss of the load device is easily caused, and the load device may be burnt out by the high voltage drift, which may affect the service life of the circuit and the equipment. Therefore, there is a need for an improved power supply circuit in the related art.

In the embodiment of the utility model provides an in, provide a power supply circuit. The power supply circuit comprises a primary winding circuit and a plurality of secondary winding circuits, wherein the primary winding circuit and the secondary winding circuits are embedded in the same magnetic core, so that the variable magnetic flux in the primary winding circuit can be transmitted to the secondary winding circuits, and the risk of leakage inductance is reduced; the changing magnetic flux of 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 rectifying module is electrically connected with the boosting module; the switching power supply module is connected with the boosting module through a line, the primary winding circuit can be powered by mains supply and correspondingly adjusts the voltage of the power supply, for example, the rectifying module can rectify the mains supply or other alternating current into direct current voltage and boost the rectified voltage to a required voltage level through the boosting module; and the switching power supply module can convert the direct-current voltage rectified by the rectifying module and boosted by the boosting module into alternating-current voltage. The driving IC can be arranged in the switching power supply module, the driving IC can change the magnetic flux of the primary winding circuit by changing the duty ratio of the output pulse, the plurality of secondary winding circuits can generate induced voltage according to the changed magnetic flux in the primary winding circuit, and the induced voltage can be used as the output voltage of the secondary winding circuits. Specifically, a primary winding circuit of the whole power supply circuit converts alternating current of a rectifier module into direct current, a switching power supply module inverts the direct current into alternating current, and the alternating current of the primary winding circuit is converted into alternating current of a first winding circuit and other secondary winding circuits under the action of a winding and a magnetic core to supply power for other equipment.

In the embodiment of the present invention, the structure of the secondary winding circuit of the power circuit is improved, the improvement here can be an improvement on one or more secondary winding circuits, for convenience of description, a secondary winding circuit of the improvement is taken as an example for explanation, and the secondary winding circuit is recorded as a first winding circuit. It can be understood that, in the embodiment of the present invention, any number of first winding circuits may be included in the secondary winding circuit; the first winding circuit and other winding circuits are also possible; the other secondary winding circuit may 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 connection of the feedback winding circuit, the winding portion of the feedback winding circuit is disposed on the secondary side, and the feedback portion thereof uses the combined circuit of the optocoupler and the TL431 chip to isolate the primary winding circuit from the secondary winding circuit.

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

Referring to fig. 1, in the embodiment of the present invention, the circuit in which the winding 1 and the winding 2 are located is a secondary winding circuit, and the circuit in which the winding 3 and the winding 4 are located is a primary winding circuit. For convenience of explanation, in the embodiment of the present invention, the secondary winding circuit where the winding 1 is located is referred to as a first winding circuit, and the secondary winding circuit where the winding 2 is located is referred to as a feedback winding circuit. The first winding circuit may include a rectifying unit and a voltage stabilizing unit; wherein, the rectifier unit can include winding 1, diode D1 and electric capacity C1 in the embodiment of the utility model provides an, winding 1 can set up different turns according to the output voltage of difference, and electrolytic capacitor can be chooseed for use to electric capacity C1, and electrolytic capacitor can be than the bigger energy of general electric capacity storage, improves rectifier unit's stability. The electrolytic capacitor can store the electric energy of the positive half period generated by the winding 1 and release the electric energy in the negative half period; the anode of the diode D1 is connected to the first winding, the cathode is connected to the anode of the capacitor C1, and the cathode of the capacitor C1 is grounded. The rectifying unit can rectify the alternating current with positive and negative half cycles output by the winding port in the first winding circuit into direct current output. In some embodiments, the voltage stabilization unit may include a first resistor R1, a second resistor R2, and a reference voltage chip U1; one end of the first resistor R1 is connected with 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 rectifying unit are grounded; one end of the second resistor R2 is connected with the first end of the rectifying unit; the other end of the second resistor R2 is connected with the feedback end of the reference voltage chip U1; the cathode terminal of the reference voltage chip U1 is connected to a first terminal of the rectifying unit. In this embodiment, the reference voltage chip U1 may be a TL431 chip, and when the first winding circuit is affected by other secondary winding circuits, which results in a floating voltage output by the rectifying unit, if the first winding circuit is directly connected to the applied load device after being rectified, the floating voltage will cause a great loss to the load device, which may affect the normal operation of the circuit. In this embodiment, the voltage regulator unit may be disposed between the rectifier unit and the applied load device, the reference voltage chip U1 of the voltage regulator unit fixes the potential of the feedback terminal to the ground due to the internal reference voltage, for example, the potential of the feedback terminal of the reference voltage chip U1 to the ground is 2.5V, that is, the voltage across the first resistor R1 is stabilized at 2.5V, and the first resistor R1 and the second resistor R2 are grounded in series, so the output voltage of the whole voltage regulator unit is finally determined by the ratio of the first resistor R1 to the second resistor R2, specifically, for example, when the resistance of the first resistor R1 is 5K ohm, the resistance of the second resistor R2 is 15K ohm, the ratio of the resistance of the first resistor R1 to the resistance of the second resistor R2 is 1:3, according to the characteristics of the series circuit, the voltage drop ratio of the voltage regulator unit is also 1:3, and the voltage regulation output of the voltage regulator unit depends on the sum of the voltage drop of the first resistor R1 and the second resistor R2, the output voltage of the voltage stabilization unit is 4 times of the reference voltage, i.e., 10V. Of course, in some embodiments of the present invention, the resistance of the second resistor may also be 0, that is, the feedback terminal of the reference voltage chip U1 may be directly shorted with the cathode, and the output of the voltage stabilizing unit will be directly stabilized at the same 2.5V as the reference voltage inside the reference voltage chip U1. For convenience, dynamic regulation voltage regulator unit makes it can adapt to different output demands, need constantly change the loaded down with trivial details operation of resistance when reducing practical application, improve the operating efficiency of circuit, optionally the utility model discloses an in some embodiments, second resistance R2 also can select to adopt adjustable resistance, and adjustable resistance's resistance adjustment range can be set for according to different voltage demands, when using, through the proportion of adjusting first resistance R1 and second resistance R2, can control the voltage value that voltage regulator unit output needs, and stable scope is littleer moreover, has further improved the degree of accuracy of stabilizing voltage. The specific circuit principle is similar to the foregoing, and is not described in detail herein.

Optionally, in the embodiment of the present invention, the reference voltage chip U1 is adopted to perform voltage stabilization output, as mentioned above, the model of this chip may be TL431, and it includes an operational amplifier and a triode inside, 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, the larger current flows into the reference voltage chip U1 through this branch, and it is possible to make the reference voltage chip U1 have the risk of being broken down. Therefore, in order to protect the reference voltage chip U1 and adapt it to the voltage regulation requirement of a larger current range, in some embodiments, the first winding circuit in the embodiment of the present invention may further include a protection resistor R3, and the specific connection of the protection resistor R3 may refer to fig. 2. Specifically, the protection resistor R3 may be disposed on the line connecting the cathode of the reference voltage chip U1 and the rectifying unit, so that when a larger current passes through the line connecting the rectifying unit and the cathode of the reference voltage chip U1, the protection resistor R3 may effectively limit the current flowing to the cathode of the reference voltage chip U1, and reduce the risk of burning out the reference voltage chip U1. Due to the existence of the protective resistor R3, the whole voltage stabilizing circuit can also adapt to larger current input, thereby improving the available current range of the whole 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 reference voltage inside the chip, and ensure that the voltage drop of the first resistor R1 is 2.5V, the current passing through the feedback end thereof needs to be maintained at a certain value, for example, the current needs to be greater than 1uA, so in this application, the resistance value of the protection resistor R3 may be set in a certain range, so that the current passing through the cathode of the reference voltage chip U1 meets the above requirements.

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 include a shunt unit behind the voltage stabilizing unit. Specifically, referring to fig. 3, the shunt unit in fig. 3 includes a fourth resistor R4, a fifth resistor R5, and a transistor Q1. The transistor Q1 may be an NPN transistor, and in some embodiments, the transistor may also be a PNP transistor. One end of the fourth resistor R4 is connected to the first end of the rectifying unit, 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, the other end of the fifth resistor R5 is grounded together with the second end of the rectifying unit, and the collector of the transistor Q1 is connected to the first end of the rectifying unit. In the shunt unit shown in fig. 3, the fourth resistor R4 can share the current flowing to the regulator unit and simultaneously play a role of protecting the transistor Q1, so as to prevent the transistor Q1 from being broken down due to an excessive current flowing to the transistor Q1. The fifth resistor R5 can consume the energy generated by the first winding circuit due to voltage drift, so that the phenomenon that the voltage stabilizing unit generates heat abnormally due to the fact that the voltage stabilizing unit is loaded by excessive energy is avoided, and the practicability and the service life of the voltage stabilizing unit are further improved. When a larger current output by the rectifying unit passes through a branch where a cathode of the reference voltage chip U1 is located, because an input end of the shunting module is connected to a line node of the output end of the rectifying unit and the protection resistor R3, according to the kirchhoff's law, the larger current can respectively flow to a branch where the protection resistor R3 is located and a branch where the fourth resistor R4 is located, under the action of the current, the voltage stabilizing unit normally works, the voltage output by the voltage stabilizing unit can conduct a base of the triode Q1, after the base of the triode Q1 is conducted, the branch where an emitter and a collector are located is also conducted, and the fifth resistor R5 of the branch where the emitter is located can absorb energy generated by voltage drift so as to further stabilize the output voltage of the first winding circuit. Further optionally, in the embodiment of the present invention, the fifth resistor R5 may also be replaced by other loaded devices or modules, or a combination of resistors and LEDs.

In addition, in the embodiment of the present invention, the first winding circuit may further include an absorption unit, the absorption unit may be composed of three absorption loads and a load control module connected in parallel, the absorption load may select a static load such as a resistor, the circuit of the absorption load refers to fig. 4, in fig. 4, the absorption load includes a plurality of field effect transistors and resistors including a first field effect transistor K1, a second field effect transistor K2, a third field effect transistor K3, a first absorption resistor RS1, a second absorption resistor RS2, and a third absorption resistor RS3, a gate of each field effect transistor is connected with the load control module, and the load control module may select to turn on or turn off loads of different numbers or different branches according to a change of the output voltage of the first winding circuit. Optionally, in the absorption unit, the fet functions to control the branch in which the absorption load is located to be turned on or off, and therefore, in some embodiments, the fet may also be replaced by a commonly used NPN or PNP transistor. Specifically, when the first winding circuit is affected by other secondary winding circuits to cause the output voltage of the first winding circuit to be floated, and 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 electric signal to control the first field-effect transistor K1 to be turned on, the load-absorbing resistor RS1 can absorb the floated voltage to keep the output voltage of the first winding voltage within a threshold range, if the branch where the first field-effect transistor K1 is located still cannot eliminate the floated voltage of the first winding voltage, the load control module can send an electric signal to control the second field-effect transistor K2 and the third field-effect transistor K3 to be turned on, the first winding voltage is kept stable through the absorption of multiple branches, and the design of multiple branches can enable the first winding circuit to be adapted to more loads or devices with different powers. It is understood that, in the embodiment of the present invention, the absorption loads are not limited to three, and may be more. In addition, because the absorption unit has a plurality of branches, when the first fet K1, the second fet K2, and the third fet K3 are turned on and the load control module detects that the output voltage of the first winding circuit is less than the threshold, the load control module may control to turn off any one of the branches of the first fet K1, the second fet K2, or the third fet, and if one branch is turned off, the voltage of the first winding circuit is still higher than the threshold, and the load control module may further control the branch where the other fet is located to turn off, so that the voltage of the first winding circuit is stabilized within the threshold range. Optionally, in the embodiment of the present invention, the resistors of each branch of the absorption load may also be resistors with different resistances, and the absorption efficiency is further optimized by the difference of the absorption capacities with different resistances; the adjustable resistor can also be directly selected on a single branch, and the absorption efficiency of the branch can be adjusted by switching different resistance values through the adjustable resistor. Further optionally, in the embodiment of the utility model provides an in, the absorption load also can be dynamic absorption load such as LED or LCD screen, through the power of adjustment dynamic absorption load, has accelerated the absorption unit to the defeated efficiency that floats high voltage of first winding circuit and energy absorption thereof. And the embodiment of the utility model provides a combined the advantage of absorption unit, steady voltage unit and reposition of redundant personnel unit, made the embodiment of the utility model provides a possess the adaptability of wideer voltage and electric current, can adapt to the switching power supply circuit of the electrical parameter of multiple difference, satisfy the improvement requirement of relevant personnel to cross adjustment voltage, further improved the utility model discloses a practicality.

The present application further provides an electrical device. The electrical device comprises at least one or more of the power supply circuits of the above embodiments; the power supply circuit comprises a primary winding circuit and a plurality of secondary winding circuits; the plurality of secondary winding circuits comprise a first winding circuit; the first winding circuit comprises a rectifying unit and a voltage stabilizing unit; the voltage stabilizing unit comprises a first resistor, a second resistor and a reference voltage chip; one end of the first resistor is connected with 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 rectifying unit are grounded; one end of the second resistor is connected with the first end of the rectifying unit, and the other end of the second resistor is connected with the feedback end of the reference voltage chip; the cathode terminal of the reference voltage chip is connected with the first terminal of the rectifying unit.

It can be understood that, since the electrical device adopts all the technical solutions of the power supply circuit of the above embodiment, at least all the beneficial effects brought by the technical solutions of the above embodiments are achieved, and are not described herein again.

To sum up, the utility model relates to a power supply circuit and electrical equipment has following advantage:

(1) the stability is good. The utility model discloses having add the steady voltage unit in first winding circuit, having improved the influence of other secondary winding circuit to first winding circuit through the steady voltage effect of steady voltage unit, reduced first winding circuit output voltage's fluctuation, improved the stability of first winding circuit output.

(2) Simple structure and low cost. The embodiment of the utility model provides an in power supply circuit adopts basic elements such as resistance and electric capacity more, and structure complexity is low, can significantly reduce manufacturing cost, the benefit of improving.

(3) The first winding circuit comprises an absorption unit, and the suppression performance on high floating voltage is good.

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

(5) The voltage application range is wide, and the suppression can be performed on output circuits in different voltage ranges.

(6) The first winding circuit comprises a shunt unit, and can be suitable for input and output of large current.

In the foregoing description of the specification, reference to the description of "one embodiment/example," "another embodiment/example," or "certain embodiments/examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that: numerous changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the application, the scope of which is defined by the claims and their equivalents.

While the present application has been described with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A power supply circuit is characterized by comprising a primary winding circuit and a plurality of secondary winding circuits; the secondary winding circuits comprise a first winding circuit;

the first winding circuit comprises a rectifying unit and a voltage stabilizing unit used for reducing the fluctuation of the output voltage of the first winding circuit, and the rectifying unit is connected with the voltage stabilizing unit.

2. The power supply circuit according to claim 1, wherein the voltage stabilizing unit comprises a first resistor, a second resistor and a reference voltage chip; one end of the first resistor is connected with 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 rectifying unit are grounded; one end of the second resistor is connected with the first end of the rectifying unit, and the other end of the second resistor is connected with the feedback end of the reference voltage chip; and the cathode end of the reference voltage chip is connected with the first end of the rectifying unit.

3. The power supply circuit according to claim 2, wherein the voltage stabilization unit further includes a protection resistor; the protection resistor is arranged on a line connecting the cathode end of the reference voltage chip and the first end of the rectifying unit.

4. A power supply circuit according to any one of claims 2 or 3, wherein the first winding circuit further comprises a snubber unit; the first end of the absorption unit is connected with the first input end of the rectification unit; and the second end of the absorption unit is connected with the second end of the rectification unit.

5. A power supply circuit according to claim 4, wherein the absorption unit comprises an absorption load; the absorptive load comprises at least one or a combination of more of a resistor, an LED light, or an LCD screen.

6. A power supply circuit according to claim 1, wherein the first winding circuit further comprises a shunt unit; the shunt unit comprises a fourth resistor, a fifth resistor and a triode; one end of the fourth resistor is connected with the base electrode of the triode; one end of the fourth resistor is also connected with the cathode end of the reference voltage chip; the other end of the fourth resistor is connected with the first end of the rectifying unit; and the collector of the triode is connected to the first end of the rectifying unit, the emitter of the triode is connected with one end of the fifth resistor, and the other end of the fifth resistor is grounded.

7. The power supply circuit according to claim 4, wherein the first winding circuit further comprises a shunt unit; the shunt unit comprises a fourth resistor, a fifth resistor and a triode; one end of the fourth resistor is connected with the base electrode of the triode; one end of the fourth resistor is also connected with the cathode end of the reference voltage chip; the other end of the fourth resistor is connected with the first end of the rectifying unit; and the collector of the triode is connected to the first end of the rectifying unit, the emitter of the triode is connected with one end of the fifth resistor, and the other end of the fifth resistor is grounded.

8. A power supply circuit as claimed in claim 2, wherein the second resistor is an adjustable resistor.

9. A power supply circuit according to claim 1, wherein the rectifying unit comprises a diode and a capacitor.

10. The power supply circuit of claim 1, further comprising a feedback winding circuit among said plurality of secondary winding circuits; the feedback winding circuit comprises an optical coupler; the optical coupler is used for electrically isolating the primary winding circuit and the secondary winding circuit.

11. The power supply circuit according to claim 1, wherein the primary winding circuit comprises a rectifying module, a boosting module and a switching power supply module; the rectifying module is connected with the boosting module; the boosting module is connected with the switching power supply module.

12. An electrical device, characterized by: comprising a power supply circuit according to any of claims 1-11.