A power-on self-starting circuit and a control method thereof

Abstract

The application relates to the technical field of circuits, in particular to a power-on self-starting circuit and a control method thereof, which comprises a power supply end, a first capacitor, a second capacitor, a first discharging circuit, a second discharging circuit, a power conversion circuit, a self-starting circuit and a main control module; the first discharging circuit is used for releasing the electric energy stored in the first capacitor and the second capacitor when the power supply end is disconnected; the second discharging circuit is used for releasing the electric energy stored in the main control module when the power supply end is disconnected; the self-starting circuit is used for pulling down the level of the power input port and the start-up pin of the main control module when the power supply end is connected, and triggering the main control module to start; and the power conversion circuit is used for converting the voltage input by the power supply end into a power supply voltage suitable for the main control module; the application can support the repeated and rapid power-on and power-off of electronic products and realize automatic start-up when the electronic products are powered on.

Description

Technical Field

[0001] This invention relates to the field of circuit technology, specifically to a power-on self-starting circuit and its control method. Background Technology

[0002] When electronic products are repeatedly and rapidly powered on and off, the voltage on the power supply path cannot change abruptly, which may cause the self-starting circuit to malfunction, thus preventing the electronic product from turning on automatically. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a power-on self-starting circuit and its control method, which can enable automatic power-on when electronic products are repeatedly and rapidly powered on and off.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] A power-on self-starting circuit includes: a power supply terminal, a first capacitor, a second capacitor, a first discharge circuit, a second discharge circuit, a power conversion circuit, a self-starting circuit, and a main control module;

[0006] The power supply terminal is connected to the first capacitor, the first discharge circuit, the second discharge circuit, and the power conversion circuit, respectively. The power conversion circuit is connected to the second capacitor, the self-starting circuit, and the main control module, respectively. The main control module is also connected to the second discharge circuit.

[0007] The first discharge circuit is used to release the electrical energy stored in the first capacitor and the second capacitor when the power supply terminal is disconnected from the input.

[0008] The second discharge circuit is used to release the electrical energy stored in the main control module when the power supply terminal is disconnected from the input;

[0009] The self-starting circuit is used to pull down the power input port and power-on pin of the main control module when the power supply terminal is turned on, thereby triggering the main control module to power on and start.

[0010] The power conversion circuit is used to convert the voltage input to the power supply terminal into a power supply voltage that is compatible with the main control module.

[0011] Furthermore, the first discharge circuit includes: a first resistor, a second resistor, a third resistor, and a first field-effect transistor. One end of the first resistor and the input terminal of the power conversion circuit are connected to the power supply terminal, and the other end is connected to one end of the second resistor and the gate of the first field-effect transistor. The other end of the second resistor and the source of the first field-effect transistor are grounded together. The drain of the first field-effect transistor is connected to one end of the third resistor, and the other end of the third resistor is connected to the output terminal of the power conversion circuit.

[0012] Furthermore, the second discharge circuit includes a fourth resistor, a fifth resistor, a sixth resistor, and a second field-effect transistor. One end of the fourth resistor is connected to the power supply terminal, and the other end is connected to one end of the fifth resistor and the gate of the second field-effect transistor. The other end of the fifth resistor and the source of the second field-effect transistor are grounded together. The drain of the second field-effect transistor is connected to one end of the sixth resistor, and the other end of the sixth resistor is connected to the power-on pin of the main control module.

[0013] Furthermore, the self-starting circuit includes: a seventh resistor, an eighth resistor, a ninth resistor, a pull-up capacitor, a debouncing capacitor, a diode, and a transistor. One end of the seventh resistor is connected to the power-on pin of the main control module, and the other end is connected to the collector of the transistor. The base of the transistor is connected to one end of the eighth resistor and one end of the debouncing capacitor. The other end of the eighth resistor is connected to one end of the ninth resistor, the cathode of the diode, and one end of the pull-up capacitor. The emitter of the transistor, the other end of the debouncing capacitor, the other end of the ninth resistor, and the anode of the diode are all grounded. The other end of the pull-up capacitor is connected to the power input port of the main control module and the output terminal of the power conversion circuit.

[0014] Furthermore, the self-starting circuit employs a reset chip.

[0015] Furthermore, the first field-effect transistor is a P-channel junction field-effect transistor or a depletion-mode field-effect transistor.

[0016] Furthermore, the second field-effect transistor is a P-channel junction field-effect transistor or a depletion-mode field-effect transistor.

[0017] Furthermore, both the first capacitor and the second capacitor are electrolytic capacitors.

[0018] Furthermore, the power supply terminal is used to provide DC power, and the power conversion circuit is a DC / DC power conversion circuit.

[0019] A control method for a power-on self-starting circuit, applied to any of the power-on self-starting circuits described above, the method comprising the following steps:

[0020] Step S100: When the power supply terminal is turned on, the power conversion circuit converts the voltage input to the power supply terminal into a power supply voltage that is compatible with the main control module.

[0021] Step S200: When the power input port of the main control module receives the power supply voltage, the self-starting circuit debouncing the power supply voltage pulls down the level of the power-on pin of the main control module, triggering the main control module to power on and start.

[0022] Step S300: When the power supply terminal is disconnected from the input, the first discharge circuit releases the electrical energy stored in the first capacitor and the second capacitor, and the second discharge circuit releases the electrical energy stored in the main control module.

[0023] The beneficial effects of the present invention are as follows: The present invention provides a power-on self-starting circuit and its control method. By adding a first discharge circuit and a second discharge circuit to a conventional power-on self-starting circuit, the first capacitor, the second capacitor, and the main control module are rapidly discharged, so that the circuit can ensure that the power-on pin is pulled low to trigger the power-on even under repeated rapid power-on and power-off operations. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a circuit block diagram of a power-on self-starting circuit according to an embodiment of the present invention;

[0026] Figure 2 This is a circuit diagram of a power-on self-starting circuit according to an embodiment of the present invention;

[0027] Figure 3 This is a simulation diagram of a power-on self-starting circuit according to an embodiment of the present invention. Detailed Implementation

[0028] This section will describe in detail specific embodiments of the present invention. Preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present invention, but they should not be construed as limiting the scope of protection of the present invention.

[0029] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0030] In the description of this invention, if there are words such as "several", they mean one or more, "multiple" means two or more, "greater than", "less than", "exceeding" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself.

[0031] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0032] In related technologies, for electronic products that require automatic power-on functionality, a self-starting circuit is generally composed of discrete components or a reset chip. Regardless of whether a discrete component or a reset chip is used, the circuit contains energy storage devices such as capacitors, especially large-capacity electrolytic capacitors. When the electronic product is repeatedly and rapidly powered on and off, the stored electrical energy in the capacitors, coupled with the fact that the voltage on the power supply path cannot change abruptly, may cause the self-starting circuit to malfunction, thus preventing the electronic product from automatically powering on.

[0033] Based on this, the present invention provides a power-on self-starting circuit and its control method. By adding a first discharge circuit 100 and a second discharge circuit 200 to a conventional power-on self-starting circuit, the first capacitor C1, the second capacitor C2, and the main control module U1 are rapidly discharged, so that the circuit can ensure that the power-on pin is pulled low to trigger the power-on even under repeated rapid power-on and power-off operations.

[0034] refer to Figure 1 This invention provides a power-on self-starting circuit, including: a power supply terminal DC_IN, a first capacitor C1, a second capacitor C2, a first discharge circuit 100, a second discharge circuit 200, a power conversion circuit U2, a self-starting circuit 300, and a main control module U1;

[0035] The power supply terminal DC_IN is connected to the first capacitor C1, the first discharge circuit 100, the second discharge circuit 200 and the power conversion circuit U2 respectively. The power conversion circuit U2 is connected to the second capacitor C2, the self-starting circuit 300 and the main control module U1 respectively. The main control module U1 is also connected to the second discharge circuit 200.

[0036] The first discharge circuit 100 is used to release the electrical energy stored in the first capacitor C1 and the second capacitor C2 when the power supply terminal DC_IN is disconnected from the input.

[0037] The second discharge circuit 200 is used to release the electrical energy stored in the main control module U1 when the power supply terminal DC_IN is disconnected from the input;

[0038] The self-starting circuit 300 is used to pull down the power input port and power-on pin of the main control module U1 when the power supply terminal DC_IN is turned on, thereby triggering the main control module U1 to power on and start.

[0039] The power conversion circuit U2 is used to convert the voltage input at the power supply terminal DC_IN into a power supply voltage that is compatible with the main control module U1.

[0040] It should be noted that in this embodiment, the first discharge circuit 100 rapidly releases the electrical energy in the first capacitor C1 and the second capacitor C2, and the second discharge circuit 200 rapidly releases the electrical energy in the main control module U1. The power input port and power-on pin of the main control module U1 can be quickly pulled low when the power is cut off, and when the power is restored, the power-on pin can be pulled low to trigger power-on. This ensures that even under repeated rapid power-on and power-off operations, the power-on pin level of the main control module U1 can be pulled low to trigger power-on. In the embodiment provided in this application, by adding the first discharge circuit 100 and the second discharge circuit 200 to the conventional power-on self-starting circuit, rapid discharge of the power supply terminal DC_IN and the main control module U1 is achieved, ensuring that the power-on pin is pulled low to trigger power-on even under repeated rapid power-on and power-off operations.

[0041] refer to Figure 2 As a preferred embodiment of the above, the first discharge circuit 100 includes: a first resistor R1, a second resistor R2, a third resistor R3, and a first field-effect transistor Q1. One end of the first resistor R1 and the input terminal of the power conversion circuit U2 are connected to the power supply terminal DC_IN, and the other end is connected to one end of the second resistor R2 and the gate of the first field-effect transistor Q1. The other end of the second resistor R2 and the source of the first field-effect transistor Q1 are grounded together. The drain of the first field-effect transistor Q1 is connected to one end of the third resistor R3, and the other end of the third resistor R3 is connected to the output terminal of the power conversion circuit U2.

[0042] In this embodiment, the first resistor R1 and the second resistor R2 form the gate bias circuit of the first field-effect transistor Q1. The first resistor R1 serves as the pull-up resistor of the first field-effect transistor Q1, the second resistor R2 serves as the pull-down resistor of the first field-effect transistor Q1, and the third resistor R3 serves as the current-limiting resistor of the first field-effect transistor Q1.

[0043] It should be noted that in this embodiment, when a DC power supply is input to the power supply terminal DC_IN, since the first resistor R1 and the second resistor R2 act as voltage dividers, the voltage of the first field-effect transistor Q1 is V1gs > V1gs(off) > 0, so the first field-effect transistor Q1 is cut off and does not conduct, and the drain-source terminal presents a high-resistance state; where V1gs represents the driving voltage of the first field-effect transistor Q1, and V1gs(off) represents the pinch-off voltage or threshold voltage of the first field-effect transistor Q1;

[0044] When there is no input at the DC_IN power supply terminal, due to the presence of the second resistor R2 as a pull-down resistor, Vgs = 0 < Vgs(off) of the first field-effect transistor Q1. This causes the drain-source terminal of the first field-effect transistor Q1 to conduct, allowing the electrical energy stored in the first capacitor C1 to be rapidly discharged through the path formed by the third resistor R3 and the drain-source terminal of the first field-effect transistor Q1. Similarly, the electrical energy stored in the second capacitor C2 is rapidly discharged through the path formed by the power conversion circuit U2, the third resistor R3, and the drain-source terminal of the first field-effect transistor Q1. Typically, the value of the third resistor R3 should not be too large.

[0045] As a preferred embodiment of the above, the second discharge circuit 200 includes: a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, and a second field-effect transistor Q2. One end of the fourth resistor R4 is connected to the power supply terminal DC_IN, and the other end is connected to one end of the fifth resistor R5 and the gate of the second field-effect transistor Q2. The other end of the fifth resistor R5 and the source of the second field-effect transistor Q2 are grounded together. The drain of the second field-effect transistor Q2 is connected to one end of the sixth resistor R6, and the other end of the sixth resistor R6 is connected to the power-on pin of the main control module U1.

[0046] In this embodiment, the fourth resistor R4 and the fifth resistor R5 form the gate bias circuit of the second field-effect transistor Q2, and the sixth resistor R6 is the current-limiting resistor of the second field-effect transistor Q2. When the power supply terminal DC_IN receives a DC power supply, the fourth resistor R4 and the fifth resistor R5 act as voltage dividers, making V2gs > V2gs(off) > 0 for the second field-effect transistor Q2. Therefore, the second field-effect transistor Q2 is cut off and not conducting, with its drain-source terminals exhibiting a high-impedance state. Here, V2gs represents the driving voltage of the second field-effect transistor Q2, and V2gs(off) represents the pinch-off voltage or threshold voltage of the second field-effect transistor Q2. When there is no input to the power supply terminal DC_IN, the fifth resistor R5 acts as a pull-down resistor, making V2gs = 0 < V2gs(off) for the second field-effect transistor Q2. This allows the second field-effect transistor Q2 to conduct, enabling the electrical energy stored inside the main control module U1 to be quickly discharged through the path formed by the sixth resistor R6 and the drain-source terminals of the second field-effect transistor Q2. Generally, the value of the sixth resistor R6 should not be too large.

[0047] As a preferred embodiment of the above embodiment, the self-starting circuit 300 includes: a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a pull-up capacitor C4, a debouncing capacitor C3, a diode D1, and a transistor Q3. One end of the seventh resistor R7 is connected to the power-on pin of the main control module U1, and the other end is connected to the collector of the transistor Q3. The base of the transistor Q3 is connected to one end of the eighth resistor R8 and one end of the debouncing capacitor C3. The other end of the eighth resistor R8 is connected to one end of the ninth resistor R9, the cathode of the diode D1, and one end of the pull-up capacitor C4. The emitter of the transistor Q3, the other end of the debouncing capacitor C3, the other end of the ninth resistor R9, and the anode of the diode D1 are all grounded. The other end of the pull-up capacitor C4 is connected to the power input port of the main control module U1 and the output terminal of the power conversion circuit U2.

[0048] It should be noted that in this embodiment, when the DC power supply terminal DC_IN receives DC power, the voltage difference across the pull-up capacitor C4 cannot change abruptly. The potential across the pull-up capacitor C4 is equal to the voltage value at the output terminal of the power conversion circuit U2. The cathode of diode D1 is at a high level. After being current-limited by the eighth resistor R8 as a pull-up resistor, energy is stored (debouncing) for the debounce capacitor C3. When the voltage of the debounce capacitor C3 reaches 0.6V, the transistor conducts, thereby pulling the power-on pin PWR_KEY of the main control module U1 low and triggering power-on. When the pull-up capacitor C4 is fully charged, due to the presence of the ninth resistor R9 as a pull-down resistor, the cathode of diode D1 returns to a low level, the transistor Q3 is cut off, and the power-on pin PWR_KEY of the main control module U1 returns to a high level, completing one power-on trigger. Generally, the power-on pin PWR_KEY is pulled low for more than 2 seconds, but it cannot be pulled low for a long time.

[0049] In some alternative embodiments, the self-starting circuit 300 employs a reset chip.

[0050] It should be noted that in some optional embodiments, the self-starting circuit 300 may use a reset chip of model SGM802, SGM804, etc.

[0051] As a preferred embodiment of the above, the transistor Q3 is an NPN transistor Q3.

[0052] As a preferred embodiment of the above, the first field-effect transistor Q1 is a P-channel junction field-effect transistor or a depletion-mode field-effect transistor.

[0053] As a preferred embodiment of the above, the second field-effect transistor Q2 is a P-channel junction field-effect transistor or a depletion-mode field-effect transistor.

[0054] In the embodiments provided in this application, the first discharge circuit 100 and the second discharge circuit 200 utilize the conduction characteristics of a P-channel junction field-effect transistor (JFET). As long as the gate-source voltage is greater than the gate-source pinch-off voltage under normal power-on conditions, the configuration of the gate-source voltage divider resistors is highly flexible. When the voltage divider resistors are configured appropriately, the P-channel JFET can also be replaced by a depletion-mode JFET by adjusting the value of the voltage divider resistors to match the new gate-source pinch-off voltage. The discharge speed of the P-channel JFET can be flexibly adjusted by adjusting the resistance values ​​of the third resistor R3 and the sixth resistor R6, which act as current-limiting resistors. The discharge speed of the power-on pin can also be flexibly adjusted by adjusting the capacitance value of the debounce capacitor C3. This improves the flexibility of the components used in the circuit.

[0055] As a preferred embodiment of the above, both the first capacitor C1 and the second capacitor C2 are electrolytic capacitors.

[0056] It should be noted that an electrolytic capacitor is a type of capacitor. The metal foil is the positive electrode (aluminum or tantalum), and the oxide film (aluminum oxide or tantalum pentoxide) in close contact with the metal is the dielectric. The cathode is composed of conductive material, electrolyte (which can be liquid or solid), and other materials. Because the electrolyte is the main component of the cathode, it is named an electrolytic capacitor. It is also crucial that the positive and negative terminals of an electrolytic capacitor be connected correctly. Aluminum electrolytic capacitors can be classified into four types: leaded aluminum electrolytic capacitors; horn-shaped aluminum electrolytic capacitors; bolt-type aluminum electrolytic capacitors; and solid aluminum electrolytic capacitors. Electrolytic capacitors have a very large capacitance per unit volume, and their rated capacitance can be very large. This embodiment uses an electrolytic capacitor as an energy storage device to leverage its large capacitance advantage.

[0057] As a preferred embodiment of the above, the power supply terminal DC_IN is used to provide DC power.

[0058] As a preferred embodiment of the above, the power conversion circuit U2 is a DC / DC power conversion circuit U2.

[0059] In the embodiments provided in this application, a DC / DC power conversion circuit U2 is used to be adapted to the power supply terminal DC_IN to convert the DC power supply voltage and convert the voltage input to the power supply terminal DC_IN into a power supply voltage adapted to the main control module U1.

[0060] refer to Figure 3 The simulation results based on the circuit simulation schematic show that, compared with the prior art, after adding the first discharge circuit 100 and the second discharge circuit 200, the power input port and the power-on pin can be quickly pulled low when the power is cut off during repeated rapid power-on and power-off. When the power is restored, the power-on pin can be pulled low to trigger the power-on.

[0061] Furthermore, embodiments of the present invention provide a control method for a power-on self-starting circuit, applied to the power-on self-starting circuit described in any of the above embodiments, the method comprising the following steps:

[0062] Step S100: When the power supply terminal is turned on, the power conversion circuit converts the voltage input to the power supply terminal into a power supply voltage that is compatible with the main control module.

[0063] Step S200: When the power input port of the main control module receives the power supply voltage, the self-starting circuit debouncing the power supply voltage pulls down the level of the power-on pin of the main control module, triggering the main control module to power on and start.

[0064] When the output of the power conversion circuit outputs a power supply voltage that is compatible with the main control module, both the power input port of the main control module and the self-starting circuit receive the power supply voltage. After the self-starting circuit debounces the power supply voltage, it pulls down the level of the power-on pin of the main control module, triggering the main control module to power on and start. After the main control module powers on and starts, the power-on pin PWR_KEY of the main control module returns to a high level, completing one power-on trigger.

[0065] Step S300: When the power supply terminal is disconnected from the input, the first discharge circuit releases the electrical energy stored in the first capacitor and the second capacitor, and the second discharge circuit releases the electrical energy stored in the main control module.

[0066] It should be noted that, corresponding to the circuit embodiments described above, in this embodiment, the first discharge circuit 100 rapidly releases the electrical energy in the first capacitor C1 and the second capacitor C2, and the second discharge circuit 200 rapidly releases the electrical energy in the main control module U1. The power input port and power-on pin of the main control module U1 can be quickly pulled low when the power is cut off, and when the power is restored, the power-on pin can be pulled low to trigger power-on. This ensures that even under repeated rapid power-on and power-off operations, the power-on pin level of the main control module U1 can be pulled low to trigger power-on. In the embodiments provided in this application, by adding the first discharge circuit 100 and the second discharge circuit 200 to the conventional power-on self-starting circuit, rapid discharge of the power supply terminal DC_IN and the main control module U1 is achieved, ensuring that the power-on pin is pulled low to trigger power-on even under repeated rapid power-on and power-off operations.

[0067] The embodiments described in this invention are for the purpose of more clearly illustrating the technical solutions of the embodiments of this invention, and do not constitute a limitation on the technical solutions provided by the embodiments of this invention. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this invention are also applicable to similar technical problems.

[0068] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of the present invention, and may include more or fewer steps than shown, or combine certain steps, or different steps.

[0069] The device embodiments described above are merely illustrative. The circuits described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network circuits. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0070] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / circuits in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0071] The terms "first," "second," "third," "fourth," etc. (if present) in the specification and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or circuits is not necessarily limited to those steps or circuits explicitly listed, but may include other steps or circuits not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0072] It should be understood that in this invention, "at least one (item)" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0073] In the several embodiments provided by this invention, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the circuit division described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple circuits or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the mutual coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, apparatus, or circuits, and may be electrical, mechanical, or other forms.

[0074] The circuits described above as separate components may or may not be physically separate. The components shown as circuits may or may not be physical circuits; that is, they may be located in one place or distributed across multiple network circuits. Some or all of the circuits can be selected to achieve the purpose of this embodiment according to actual needs.

[0075] Furthermore, the functional circuits in the various embodiments of the present invention can be integrated into a single processing circuit, or each circuit can exist physically separately, or two or more circuits can be integrated into a single circuit. The integrated circuits described above can be implemented in hardware or as software functional circuits.

[0076] The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present invention. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and spirit of the present invention should be within the scope of the claims of the present invention. Although the description of the present invention has been quite detailed and particularly of several described embodiments, it is not intended to limit itself to any of these details or embodiments or any particular embodiment, but should be regarded as effectively covering the intended scope of the present invention by referring to the appended claims and considering the prior art to provide a broad possible interpretation of these claims. Furthermore, the present invention has been described above with respect to embodiments foreseeable by the inventors in order to provide a useful description, and non-substantial modifications to the present invention that have not yet been foreseen may still represent equivalent modifications to this disclosure.

Claims

1. A power-on self-starting circuit, characterized in that, include: The system includes a power supply terminal (DC_IN), a first capacitor (C1), a second capacitor (C2), a first discharge circuit (100), a second discharge circuit (200), a power conversion circuit (U2), a self-starting circuit (300), and a main control module (U1). The power supply terminal (DC_IN) is connected to the first capacitor (C1), the first discharge circuit (100), the second discharge circuit (200) and the power conversion circuit (U2) respectively. The power conversion circuit (U2) is connected to the second capacitor (C2), the self-starting circuit (300) and the main control module (U1) respectively. The main control module (U1) is also connected to the second discharge circuit (200). The first discharge circuit (100) is used to release the electrical energy stored in the first capacitor (C1) and the second capacitor (C2) when the power supply terminal (DC_IN) is disconnected from the input; The second discharge circuit (200) is used to release the electrical energy stored in the main control module (U1) when the power supply terminal (DC_IN) is disconnected from the input; The power conversion circuit (U2) is used to convert the voltage input to the power supply terminal (DC_IN) into a power supply voltage that is compatible with the main control module (U1); The self-starting circuit (300) includes a seventh resistor (R7), an eighth resistor (R8), a first diode (D1), a pull-up capacitor (C4), a ninth resistor (R9), and a debouncing capacitor (C3). One end of the seventh resistor (R7) is connected to the power-on pin of the main control module (U1), and the other end is connected to the drain of the first field-effect transistor (Q1). One end of the eighth resistor (R8) is connected to the gate of the first field-effect transistor (Q1), and the other end is connected to the cathode of the first diode (D1) and one end of the ninth resistor (R9). The source of the first field-effect transistor (Q1) and the anode of the first diode (D1) are grounded together. One end of the pull-up capacitor (C4) is connected to the power input port of the main control module (U1). The other end of the ninth resistor (R9) is connected to one end of the debouncing capacitor (C3), and the other end of the debouncing capacitor (C3) is grounded. The other end of the pull-up capacitor (C4) is also connected to the output terminal of the power conversion circuit (U2). The self-starting circuit (300) is used to pull down the power input port and power-on pin of the main control module (U1) when the power supply terminal (DC_IN) is turned on, thereby triggering the main control module (U1) to power on and start.

2. The power-on self-starting circuit according to claim 1, characterized in that, The first discharge circuit (100) includes a first resistor (R1), a second resistor (R2), a third resistor (R3), and a second field-effect transistor (Q2). One end of the first resistor (R1) and the input terminal of the power conversion circuit (U2) are connected to the power supply terminal (DC_IN), and the other end is connected to one end of the second resistor (R2) and the gate of the second field-effect transistor (Q2). The other end of the second resistor (R2) and the source of the second field-effect transistor (Q2) are grounded. The drain of the second field-effect transistor (Q2) is connected to one end of the third resistor (R3), and the other end of the third resistor (R3) is connected to the output terminal of the power conversion circuit (U2). The second discharge circuit (200) includes a fourth resistor (R4), a fifth resistor (R5), a sixth resistor (R6), and a third field-effect transistor (Q3). One end of the fourth resistor (R4) and the input terminal of the power conversion circuit (U2) are connected to the power supply terminal (DC_IN), and the other end is connected to one end of the fifth resistor (R5) and the gate of the third field-effect transistor (Q3). The other end of the fifth resistor (R5) and the source of the third field-effect transistor (Q3) are grounded together. The drain of the third field-effect transistor (Q3) is connected to one end of the sixth resistor (R6), and the other end of the sixth resistor (R6) is connected to the power-on pin of the main control module (U1).

3. The power-on self-starting circuit according to claim 1, characterized in that, The self-starting circuit (300) includes a seventh resistor (R7), an eighth resistor (R8), a first diode (D1), and a pull-up capacitor (C4). One end of the seventh resistor (R7) is connected to the power-on pin of the main control module (U1), and the other end is connected to the drain of the first field-effect transistor (Q1). One end of the eighth resistor (R8) is connected to the gate of the first field-effect transistor (Q1), and the other end is connected to the cathode of the first diode (D1). The source of the first field-effect transistor (Q1) and the anode of the first diode (D1) are grounded together. One end of the pull-up capacitor (C4) is connected to the power input port of the main control module (U1), and the other end is also connected to the output terminal of the power conversion circuit (U2).

4. The power-on self-starting circuit according to claim 3, characterized in that, The self-starting circuit (300) includes a reset chip, the input of which is connected to the output of the power conversion circuit (U2), and the output of which is connected to the power-on pin of the main control module (U1).

5. The power-on self-starting circuit according to claim 2, characterized in that, The second field-effect transistor (Q2) is a P-channel junction field-effect transistor.

6. The power-on self-starting circuit according to claim 2, characterized in that, The third field-effect transistor (Q3) is a depletion-type field-effect transistor.

7. The power-on self-starting circuit according to claim 1, characterized in that, The first capacitor (C1) and the second capacitor (C2) are electrolytic capacitors.

8. The power-on self-starting circuit according to claim 1, characterized in that, The power conversion circuit (U2) is a DC / DC power conversion circuit or an AC / DC power conversion circuit.

9. A control method for a power-on self-starting circuit, applied to the power-on self-starting circuit according to any one of claims 1 to 8, characterized in that, Includes the following steps: When the power supply terminal (DC_IN) is turned on, the power conversion circuit (U2) converts the voltage input to the power supply terminal (DC_IN) into a power supply voltage that is compatible with the main control module (U1). The self-starting circuit (300) pulls down the level of the power input port and the power-on pin of the main control module (U1) to trigger the main control module (U1) to power on and start. When the power supply terminal (DC_IN) is disconnected from the input, the first discharge circuit (100) releases the electrical energy stored in the first capacitor (C1) and the second capacitor (C2), and the second discharge circuit (200) releases the electrical energy stored in the main control module (U1).

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