Power switch and LED lamp

Abstract

The utility model discloses a power switch and an LED lamp. The power switch comprises a switch booster circuit and an overcurrent feedback circuit, and the switch booster circuit comprises a power management chip; the switch booster circuit is used for receiving an input voltage of a power supply and boosting the input voltage to obtain an output voltage, and the power supply management chip is used for supplying power to a load through the output voltage under the control of the switch assembly; the overcurrent feedback circuit is connected to the switch booster circuit and is used for detecting the output voltage to obtain an output voltage detection result and sending the output voltage detection result to a power management chip in the switch booster circuit; and the power management chip is used for controlling the switch assembly to be switched off under the condition that the output voltage detection result is greater than the overvoltage threshold value. According to the utility model, the technical problem of over-current damage of electric equipment caused by unstable output current easily caused by power grid distortion such as arc discharge of input voltage is solved.

Description

Technical Field

[0001] The utility model relates to the field of lighting, and more specifically, to a power switch and an LED lamp. Background Art

[0002] In the power supply schemes of current electrical equipment (such as LED lighting products), the single-stage boost non-isolated switching power supply scheme is often used.

[0003] A single-stage boost non-isolated switching power supply is a power converter that converts the input voltage into a higher output voltage without providing electrical isolation. This power supply has some key features and advantages as follows:

[0004] 1. Input voltage: The single-stage boost non-isolated switching power supply receives an input voltage, usually a low voltage (e.g., 5V or 12V).

[0005] 2. Switching element: A switching element (such as a transistor or MOSFET) is used inside the power supply to control the on and off of the current. This switching element switches at a high frequency to achieve voltage conversion.

[0006] 3. Boost conversion: Through the high-frequency switching of the switching element, the inductor inside the power supply stores energy and releases it when the switching element is turned off. This makes the output voltage higher than the input voltage, achieving a boost effect.

[0007] 4. Non-isolation: Different from the isolated switching power supply, the single-stage boost non-isolated switching power supply has no electrical isolation between the input and output. This means there is a direct electrical connection between the input and output, which may cause electromagnetic interference (EMI) problems.

[0008] 5. Rectification and filtering: The boosted voltage is usually converted into direct current through a rectifier (such as a diode bridge), and then a filter capacitor is used to smooth the voltage waveform to obtain the required stable output voltage.

[0009] 6. Energy transfer efficiency: The energy transfer efficiency of the single-stage boost non-isolated switching power supply is relatively high because it avoids the additional conversion losses required by the isolated power supply.

[0010] 7. Application scenarios: Due to its simplicity and high efficiency, the single-stage boost non-isolated switching power supply is widely used in portable electronic devices, battery chargers, and other low-power applications.

[0011] Therefore, a single-stage boost non-isolated switching power supply is a power converter that converts the input voltage into a higher output voltage, with non-isolated characteristics and high efficiency. It can be applied to various portable electronic devices and low-power applications.

[0012] However, the disadvantage of this solution is that when there are power grid distortions such as arcing in the input voltage, it is easy to cause the output current to be unstable and current spikes to occur. When the current spike exceeds the maximum current that the electrical equipment can withstand, it will cause the electrical equipment to be damaged due to overcurrent.

[0013] In response to the above problems, no effective solution has been proposed yet. Utility Model Content

[0014] Embodiments of the present utility model provide a power switch and an LED lamp to at least solve the technical problem that when there are power grid distortions such as arcing in the input voltage, it is easy to cause the output current to be unstable, resulting in overcurrent damage to the electrical equipment.

[0015] According to one aspect of the embodiments of the present utility model, a power switch is provided, including: a switching boost circuit and an overcurrent feedback circuit. Among them, a power management chip is included in the switching boost circuit; the switching boost circuit is used to receive the input voltage of the power supply and boost the input voltage to obtain an output voltage. Among them, the power management chip is used to supply power to the load through the control of the switching component; the overcurrent feedback circuit is connected to the switching boost circuit and is used to detect the output voltage to obtain an output voltage detection result and send the output voltage detection result to the power management chip in the switching boost circuit; the power management chip is used to control the switching component to disconnect when the output voltage detection result is greater than the overvoltage threshold.

[0016] Optionally, the overcurrent feedback circuit is connected between the negative output terminal of the load and the overvoltage protection pin of the power management chip.

[0017] Optionally, the overcurrent feedback circuit includes a diode and a resistor. Among them, the negative output terminal is connected to the input end of the diode, the output end of the diode is connected to the overvoltage protection pin, and the resistor is connected between the negative output terminal and the ground wire.

[0018] Optionally, there are multiple resistors, and the multiple resistors are connected in series.

[0019] Optionally, the resistance value of the resistor is determined according to the overvoltage threshold and the peak current value that causes the load to be abnormal.

[0020] Optionally, the peak current value is 80%-90% of the rated current of the load.

[0021] Optionally, the power switch further includes: a rectifying and filtering circuit, wherein the rectifying and filtering circuit is configured to rectify and filter the initial voltage from the power supply to obtain the input voltage.

[0022] Optionally, the overvoltage threshold is determined according to the specifications of the switching boost circuit.

[0023] Optionally, the power management chip of the switching boost circuit is a BP2616 chip, and the overvoltage threshold is 0.5V.

[0024] According to another aspect of the present invention, there is provided a power switch, including: a rectifying and filtering circuit, a switching boost circuit, and an overcurrent feedback circuit. The switching boost circuit includes a power management chip, and the overcurrent feedback circuit includes a diode and a resistor. The input end of the rectifying and filtering circuit is connected to the output wave of the power supply, and the output end of the rectifying and filtering circuit is connected to the input end of the switching boost circuit. The rectifying and filtering circuit is configured to rectify and filter the initial voltage of the power supply to obtain the input voltage. The switching boost circuit is configured to receive the input voltage of the power supply and boost the input voltage to obtain an output voltage. The power management chip is configured to supply power to the load through the control of the switching component. The output end of the switching boost circuit is connected to the positive input end of the load, the negative output end of the load is connected to the input end of the diode, the output end of the diode is connected to the overvoltage protection pin of the power management chip, and the negative output end of the load is also connected to the resistor and then grounded. The overcurrent feedback circuit is configured to detect the output voltage to obtain an output voltage detection result and send the output voltage detection result to the power management chip. The power management chip is configured to control the switching component to disconnect when the output voltage detection result is greater than the overvoltage threshold.

[0025] According to still another aspect of the present invention, there is provided an LED lamp including the power switch according to any one of the above.

[0026] In the embodiment of the present invention, the overcurrent feedback circuit is adopted to detect the output voltage to obtain an output voltage detection result and send the output voltage detection result to the power management chip in the switching boost circuit, so that the power management chip controls the switching component to disconnect when the output voltage detection result is greater than the overvoltage threshold. Through the feedback of the overcurrent feedback circuit, the purpose of timely disconnecting the switching component when the output voltage is too large is achieved, thereby realizing the technical effect of effectively protecting the electrical equipment corresponding to the output voltage, and further solving the technical problem that the output current is unstable and the electrical equipment is damaged by overcurrent easily when the input voltage has grid distortions such as arcing. Brief Description of the Drawings

[0027] The drawings described herein are provided to further understand the present utility model and form a part of this application. The schematic embodiments of the present utility model and their descriptions are used to explain the present utility model and do not constitute an improper limitation to the present utility model. In the drawings:

[0028] Figure 1 is a schematic diagram of a power switch provided according to the present utility model;

[0029] Figure 2 is a schematic diagram of a power switch provided according to another embodiment of the utility model;

[0030] Figure 3 is a circuit diagram of an optimized single-stage boost non-isolated switching power supply solution provided according to an embodiment of the present utility model;

[0031] Figure 4 is a schematic diagram of an optimized single-stage boost non-isolated switching power supply solution provided according to an embodiment of the present utility model;

[0032] Figure 5 is a schematic diagram of an LED lamp provided according to an embodiment of the present utility model. Detailed Description of the Embodiments

[0033] In order to enable those skilled in the art to better understand the solution of the present utility model, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0034] It should be noted that the terms "first", "second", etc. in the description and claims of the present utility model and the above drawings are used to distinguish similar objects and do not necessarily need to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances so that the embodiments of the present utility model described herein can be implemented in an order different from those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a system, product, or device including a series of units does not necessarily have to be limited to those units clearly listed, but may include other units not clearly listed or inherent to these systems, products, or devices.

[0035] According to an embodiment of the present utility model, a power switch is provided, Figure 1is a schematic diagram of a power switch provided by the present utility model. As Figure 1 shown, the power switch includes: a switch boost circuit 11 and an overcurrent feedback circuit 12. Among them, the switch boost circuit 11 includes a power management chip 111; the switch boost circuit 11 is configured to receive the input voltage of the power supply and boost the input voltage to obtain an output voltage. Among them, the power management chip is configured to supply power to the load through the control of the switch component; the overcurrent feedback circuit 12 is connected to the switch boost circuit 11 and is configured to detect the output voltage to obtain an output voltage detection result and send the output voltage detection result to the power management chip in the switch boost circuit; the power management chip 111 is configured to control the switch component to disconnect when the output voltage detection result is greater than the overvoltage threshold.

[0036] In the embodiment of the present utility model, an overcurrent feedback circuit is adopted to detect the output voltage to obtain an output voltage detection result and send the output voltage detection result to the power management chip in the switch boost circuit, so that the power management chip controls the switch component to disconnect when the output voltage detection result is greater than the overvoltage threshold. Since when a current spike appears in the input voltage, it will first appear in the output voltage. Therefore, when the output voltage is preferentially detected, the switch can be disconnected in time, effectively avoiding damage to the electrical equipment caused by subsequent spike currents. Therefore, through the feedback of the overcurrent feedback circuit, the purpose of being able to disconnect the switch component in time when the output voltage is too large is achieved, thereby realizing the technical effect of effectively protecting the electrical equipment corresponding to the output voltage, and further solving the technical problem that when grid distortions such as arcing occur in the input voltage, it is easy to cause unstable output current and overcurrent damage to the electrical equipment.

[0037] Optionally, the overcurrent feedback circuit is configured to detect the output voltage to obtain an output voltage detection result. Therefore, the overcurrent feedback circuit can be located at multiple positions. For example, relatively simply, it can be directly connected between the negative output terminal of the load and the overvoltage protection pin of the power management chip. With this setting, the voltage detection result of the negative output terminal of the electrical equipment, which is the load, can be directly fed back to the power management chip for the power management chip to perform corresponding control processing based on this voltage detection result.

[0038] As an alternative embodiment, the circuit of the overcurrent feedback circuit can be implemented in various ways. For example, it can be set in a relatively simple manner. The overcurrent feedback circuit can include a diode and a resistor. Among them, the negative output terminal is connected to the input terminal of the diode, the output terminal of the diode is connected to the overvoltage protection pin, and the resistor is connected between the negative output terminal and the ground wire. The diode can achieve a simple switch design. In addition, the resistor can divide the voltage at the load output terminal. Therefore, through the above simple circuit setting of the overcurrent feedback circuit, timely feedback on the voltage at the negative output terminal can be achieved, and the effect is also good.

[0039] As an alternative embodiment, the above resistor can be one or multiple. When there are multiple resistors and they are connected in series, they can not only play a role in voltage division, but also effectively reduce the power consumption brought by the resistor.

[0040] As an alternative embodiment, the resistance value of the resistor can be directly determined based on the overvoltage threshold and the peak current value that causes the load to be abnormal. It should be noted that when the resistance value of the resistor is directly determined based on the overvoltage threshold and the peak current value that causes the load to be abnormal, it is relatively ideal. To consider other interferences or accuracy impacts, the resistance value of the resistor determined by the above method can be adjusted up and down to meet the requirements of the actual circuit.

[0041] As an alternative embodiment, the above peak current value can be directly set as the rated current of the above load. Of course, to provide a certain degree of protection for the load, the above peak current value can be set to 80%-90% of the rated current of the load.

[0042] As an alternative embodiment, to handle more frequent overcurrent situations in the subsequent circuit, the power switch further includes: a rectifier filter circuit, where the rectifier filter circuit is used to rectify and filter the initial voltage from the power supply to obtain the input voltage. By adding a rectifier filter circuit to the circuit before the switching boost circuit, it is possible to filter out relatively frequent peak voltages before the voltage is input to the switching boost circuit, so that subsequent processing is only used to handle a small number of peak currents, reducing the processing pressure on the subsequent circuit and effectively extending the life of the circuit.

[0043] As an alternative embodiment, the above overvoltage threshold can be determined according to the specifications of the switching boost circuit. For example, the type of the power management chip of the above switching boost circuit can also be various. For example, it can be a BP2616 chip. When the power management chip of the above switching boost circuit is a BP2616 chip, the above overvoltage threshold can be 0.5V.

[0044] As described above, in the current single-stage boost non-isolated switching power supply scheme for LED products in the lighting fixture category, the internal chip MOSFET is switched to store and release energy in the inductor, so that the output voltage is higher than the input voltage, thereby achieving boost conversion. At the same time, there is also a constant current control circuit inside the chip, and the converted voltage supplies constant current to the LED load. Since this power supply scheme is a single-stage non-isolated boost circuit, the disadvantage is that when there are grid distortions such as arcing in the input voltage (when the voltage fluctuates abnormally, the input voltage is poorly connected, when the input is turned on and off), it is easy to cause the output current to be unstable and current spikes are likely to occur. When the current spike exceeds the maximum current that the LED lamp bead can withstand, it will cause the LED lamp bead to be damaged by overcurrent. Therefore, this technology has the following disadvantages: when there are grid distortions such as arcing in the input voltage, such as when the voltage fluctuates abnormally, the input voltage is poorly connected, when the input is turned on and off, it is easy to cause damage to the LED lamp beads; the reliability and stability of the entire circuit are poor, which is likely to result in a low service life of the circuit and the light of the LED lamp product jitters during use. Therefore, in the related technology, when there are grid distortions such as arcing in the input voltage of the LED lamp, it causes the output current to be too large for a short time, resulting in damage to the LED lamp beads, and the circuit lacks a simple and effective protection mechanism. In addition, the traditional protection circuit adds a buck circuit at the later stage, which is costly and difficult to manufacture.

[0045] In another aspect of the present invention, a power switch is provided. Figure 2 It is a schematic diagram of a power switch provided according to another embodiment of the present invention, as Figure 2 shown. The power switch includes: a rectifier filter circuit 21, a switching boost circuit 11, and an overcurrent feedback circuit 12. Among them, the switching boost circuit 11 includes a power management chip 111, and the overcurrent feedback circuit 12 includes a diode and a resistor. Among them, the input end of the rectifier filter circuit 21 is connected to the output wave of the power supply, the output end of the rectifier filter circuit 21 is connected to the input end of the switching boost circuit, and the rectifier filter circuit 21 is used to rectify and filter the initial voltage of the power supply to obtain the input voltage; the switching boost circuit 11 is used to receive the input voltage of the power supply and boost the input voltage to obtain the output voltage. Among them, the power management chip 111 is used to supply power to the load through the control of the switching component; the output end of the switching boost circuit 11 is connected to the positive input end of the load, the negative output end of the load is connected to the input end of the diode, the output end of the diode is connected to the overvoltage protection pin of the power management chip, and the negative output end of the load is also connected to the resistor and then connected to the ground wire; the overcurrent feedback circuit 12 is used to detect the output voltage to obtain the output voltage detection result and send the output voltage detection result to the power management chip 111; the power management chip 111 is used to control the switching component to disconnect when the output voltage detection result is greater than the overvoltage threshold.

[0046] To solve the above problems in the related art, in the embodiments of the present utility model, the traditional single-stage boost non-isolated switching power supply scheme is optimized. In the traditional single-stage boost non-isolated switching power supply scheme, the boost conversion is realized through a rectifier filter circuit and a single-stage boost circuit, and the converted voltage is used to supply power to the LED lamp beads. In the embodiments of the present utility model, the traditional scheme is optimized. Figure 3 It is the circuit diagram of the optimized single-stage boost non-isolated switching power supply scheme provided according to the embodiments of the present utility model, as Figure 3 shown, an overcurrent feedback circuit from the LED negative output terminal to the OVP (overvoltage protection) pin of the chip is added to the circuit corresponding to the traditional single-stage boost non-isolated switching power supply scheme. Figure 4 It is the schematic diagram of the optimized single-stage boost non-isolated switching power supply scheme provided according to the embodiments of the present utility model, as Figure 4 shown, the LED boost chip has an internal OVP (overvoltage protection) function, and the protection mode will be automatically enabled inside the chip under abnormal conditions. The OVP overvoltage threshold of the chip can be set to 0.5V. When there are power grid distortions such as arcing in the input voltage, resulting in current spikes on the output lamp beads, and the current peak flows through the resistor, after Ip*R > 0.5V, the chip determines that an overvoltage abnormality occurs at this time, turns off the MOS, thereby reducing the current in the loop and indirectly protecting the circuit and the LED lamp beads. When specifically designing the circuit, the R9R10 resistors can be set, and the setting rule is 0.5V divided by the maximum peak current that is expected to flow through the lamp beads. Among them, this peak value can be set according to requirements. For example, it can be set at 80%-90% of the rated current of the LED lamp beads to achieve the best expected improvement effect. Through the abnormal overcurrent protection technology of the LED single-stage boost non-isolated switching power supply scheme provided by the above optional implementation manner, when there are power grid distortions such as arcing in the input, the peak current on the LED lamp beads can be effectively reduced, thereby protecting the LED lamp beads from being damaged by excessive current; moreover, the design is simple, and only a 4148 diode and several chip resistors need to be added to the circuit to achieve the protection function, which is a low-cost and high-efficiency protection circuit means.

[0047] Therefore, to solve this problem, in the embodiments of the present utility model, an output feedback circuit is added. The output feedback circuit can detect the magnitude of the output peak current and control the switching times of the MOSFET inside the chip, thereby suppressing the output of the peak current and protecting the LED lamp beads from being damaged by large current. Therefore, it has the following advantages: 1. Protect the LED lamp beads from being damaged by overcurrent under abnormal input, improve the service life of the product, and greatly enhance the service life of the lamps of the product; 2. The single-stage boost scheme belongs to a non-isolated circuit, and the entire circuit forms a loop. When the output current is large, it will cause the current of the entire loop to be large. This scheme can protect the entire circuit and greatly improve the stability and reliability of the circuit.

[0048] Figure 5 is a schematic diagram of the LED lamp provided by the embodiments of the present invention. As Figure 5 shown, the LED lamp 51 includes the power switch 52 of any one of the above.

[0049] The serial numbers of the embodiments of the present invention above are only for description and do not represent the advantages or disadvantages of the embodiments.

[0050] In the above embodiments of the present invention, the descriptions of the respective embodiments have their own emphases. For the parts not detailed in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

[0051] In the several embodiments provided by the present application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only illustrative. For example, the division of units can be a logical function division. In actual implementation, there can be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces. The indirect couplings or communication connections of units or modules can be in electrical or other forms.

[0052] The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they can be located in one place or distributed to multiple units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0053] In addition, the functional units in the various embodiments of the present invention can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above integrated units can be implemented in the form of hardware or in the form of a combination of hardware and software functional units.

[0054] An integrated unit, if it can be implemented in the form of a hardware unit and sold or used as an independent product. Based on this understanding, the technical solution of the present utility model, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a hardware combined with a software product. This software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps involved in each embodiment of the present utility model. And the aforementioned storage medium includes: various media such as a USB flash drive, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk, or an optical disc, etc., that can store program codes.

[0055] The above are only the preferred embodiments of the present utility model. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present utility model, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present utility model.

Claims

1. A power switch, characterized in that: include: A switching boost circuit and an overcurrent feedback circuit, wherein the switching boost circuit includes a power management chip; The switch boost circuit is used to receive an input voltage of a power supply and boost the input voltage to obtain an output voltage, wherein the power management chip is used to supply power to a load with the output voltage through the control of the switch component; The overcurrent feedback circuit is connected to the switching boost circuit, and is used to detect the output voltage, obtain an output voltage detection result, and send the output voltage detection result to the power management chip in the switching boost circuit; The power management chip is used to control the switch component to be disconnected when the output voltage detection result is greater than an overvoltage threshold.

2. The power switch according to claim 1, characterized in that: The overcurrent feedback circuit is connected between the negative output terminal of the load and the overvoltage protection pin of the power management chip.

3. The power switch according to claim 2, characterized in that: The overcurrent feedback circuit includes a diode and a resistor, wherein the cathode output terminal is connected to the input terminal of the diode, the output terminal of the diode is connected to the overvoltage protection pin, and the resistor is connected between the cathode output terminal and the ground line.

4. The power switch according to claim 3, characterized in that: There are multiple resistors, and the multiple resistors are connected in a correlated manner.

5. The power switch according to claim 3, characterized in that: The resistance value of the resistor is determined according to the overvoltage threshold and the peak current value causing the load abnormality.

6. The power switch according to claim 5, characterized in that: The peak current value is 80%-90% of the rated current of the load.

7. The power switch according to claim 1, characterized in that: The power switch further includes: a rectifying and filtering circuit, wherein the rectifying and filtering circuit is used to rectify and filter the initial voltage from the power supply to obtain the input voltage.

8. The power switch according to any one of claims 1 to 7, characterized in that: The overvoltage threshold is determined according to the specification of the switching boost circuit.

9. The power switch according to claim 8, characterized in that: The power management chip of the switching boost circuit is a BP2616 chip, and the overvoltage threshold is 0.5V.

10. An LED lamp, characterized in that: A power switch comprising the power switch according to any one of claims 1 to 9.

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