A photosensitive control circuit and an electric appliance

Abstract

The embodiment of the present application provides a photosensitive control circuit and an electric appliance, which comprise a photosensitive detection unit, a first switch unit, a first energy storage unit and a second switch unit; the photosensitive detection unit is used for generating a first signal to the second switch unit according to the ambient light intensity; when the first signal is lower than the conduction threshold value of the second switch unit, the second switch unit turns on the connection between the second end of the second switch unit and the third end of the second switch unit, so that the first power supply makes the first energy storage unit work in a charging state through the second switch unit; then, the first energy storage unit outputs a second signal to the first switch unit, and then the first switch unit turns on the connection between the second end of the first switch unit and the third end of the first switch unit, so that the first power supply is connected to the output end through the first switch unit, so that the output end obtains the voltage signal of the first power supply. The circuit adopts a pure hardware circuit to realize photosensitive control, and can reduce the circuit cost and power consumption.

Description

Technical Field

[0001] This invention relates to the field of hardware circuit technology, and in particular to a photosensitive control circuit and electrical appliance. Background Technology

[0002] Existing photosensitivity solutions typically utilize integrated photosensors and integrated sensing chips for circuit design. The integrated sensing chip detects ambient light intensity, and the integrated photosensor outputs a signal, which is then used by software settings to determine and control alarms. This approach involves complex algorithm programming, where the comparators and signal amplifiers of the integrated chip require software programming to implement photosensitivity and judgment control. In this approach, a microcontroller, sensing chip, and sensor are often used together to control the recognition of natural light and output signals. This method requires software programming control, resulting in high design costs and failing to meet the design requirements of low-cost and low-power products. Summary of the Invention

[0003] The present invention mainly provides a photosensitive control circuit and electrical appliance, which can reduce the cost and power consumption of the circuit.

[0004] In a first aspect, one technical solution adopted in the embodiments of the present invention is as follows: a photosensitive control circuit is provided, comprising: a photosensitive detection unit, a first switching unit, a first energy storage unit, and a second switching unit; a first end of the photosensitive detection unit is connected to a first power supply, and a second end of the photosensitive detection unit is connected to the first end of the second switching unit; the photosensitive detection unit is used to generate a first signal to the second switching unit according to the ambient light intensity; a second end of the second switching unit is connected to the first power supply, and a third end of the second switching unit is connected to the first end of the first energy storage unit; the second switching unit is used to conduct the connection between the second end and the third end of the second switching unit according to the first signal, so that the first energy storage unit operates in a charging state; the second end of the first energy storage unit is connected to the first end of the first switching unit, and the first energy storage unit outputs a second signal to the first switching unit when operating in the charging state; the second end of the first switching unit is connected to the first power supply, and the third end of the first switching unit is connected to an output terminal; the first switching unit is used to conduct the connection between the second end and the third end of the first switching unit when the second signal satisfies a preset conduction condition of the first switching unit, so that the first power supply is connected to the output terminal.

[0005] In some embodiments, the photosensitive control circuit further includes a second energy storage unit; a first end of the second energy storage unit is connected to a third end of the first switching unit, and a second end of the second energy storage unit is connected to a first end of the first switching unit.

[0006] In some embodiments, the photosensitive control circuit further includes a button; a first end of the button is used to connect to the first power supply, and a second end of the button is connected to the first end of the first switching unit.

[0007] In some embodiments, the photosensitive control circuit further includes a first diode; the anode of the first diode is connected to the second terminal of the second energy storage unit, and the cathode of the first diode is connected to the first terminal of the first switching unit.

[0008] In some embodiments, the photosensitive control circuit further includes a second diode; the cathode of the second diode is connected to the second terminal of the second energy storage unit, and the anode of the second diode is grounded.

[0009] In some embodiments, the photosensitive detection unit includes a photodiode and a voltage divider module; the cathode of the photodiode is connected to the first power supply, the anode of the photodiode is connected to the first terminal of the voltage divider module, the second terminal of the voltage divider module is connected to the first terminal of the second switching unit, and the third terminal of the voltage divider module is grounded.

[0010] In some embodiments, the first switching unit includes a first switching transistor and a second switching transistor; a first end of the first switching transistor is used to connect to a first power supply, a second end of the first switching transistor is connected to the first end of the second switching transistor, a third end of the first switching transistor is used to connect to the output terminal, a second end of the second switching transistor is connected to the second end of the first energy storage unit, and a third end of the second switching transistor is grounded.

[0011] In some embodiments, the first switching unit further includes a first resistor and a second resistor; the first resistor is connected between a first end of the first switching transistor and a second end of the first switching transistor, and the second resistor is connected between a second end of the first switching transistor and a first end of the second switching transistor.

[0012] In some embodiments, the second switching unit includes a third switching transistor; a first end of the third switching transistor is connected to the first power supply, a second end of the third switching transistor is connected to the second end of the photosensitive detection unit, and a third end of the third switching transistor is connected to the first end of the first energy storage unit.

[0013] In some embodiments, the second switching unit further includes a third resistor; the third resistor is connected between the third terminal of the third switching transistor and ground.

[0014] In some embodiments, the first energy storage unit includes a first capacitor and a fourth resistor; a first terminal of the first capacitor is connected to a third terminal of the second switching unit, a second terminal of the first capacitor is connected to a first terminal of the first switching unit and a first terminal of the fourth resistor, and a second terminal of the fourth resistor is grounded.

[0015] In some embodiments, the second energy storage unit includes a second capacitor; a first end of the second capacitor is connected to a third end of the first switching unit, and a first end of the second capacitor is connected to a first end of the first switching unit.

[0016] In some embodiments, the photosensitive control circuit further includes an input port and an output port; the first end of the input port is connected to the first end of the photosensitive detection unit, the second end of the first switching unit, and the second end of the second switching unit, respectively, and the second end of the input port is grounded, and the input port is used to connect to the first power supply; the first end of the output port is connected to the third end of the first switching unit, the second end of the output port is grounded, and the output port is used to connect to the output terminal.

[0017] In some embodiments, the photosensitive control circuit further includes a light-emitting unit, the first end of which is connected to the third end of the first switching unit, and the second end of which is grounded.

[0018] In a second aspect, embodiments of the present invention also provide an electrical appliance, including a photosensitive control circuit as described in any one of the first aspects.

[0019] The beneficial effects of the embodiments of the present invention are as follows: Unlike existing technologies, the embodiments of the present invention provide a photosensitive control circuit and electrical appliance, including a photosensitive detection unit, a first switching unit, a first energy storage unit, and a second switching unit. The photosensitive detection unit generates a first signal to the second switching unit based on the ambient light intensity. When the first signal is lower than the conduction threshold of the second switching unit, the second switching unit connects the second terminal and the third terminal of the second switching unit, allowing the first power supply to charge the first energy storage unit through the second switching unit. Then, the first energy storage unit outputs a second signal to the first switching unit. Next, the first switching unit connects the second terminal and the third terminal of the first switching unit, allowing the first power supply to connect to the output terminal through the first switching unit, thereby allowing the output terminal to receive the voltage signal of the first power supply. This circuit uses pure hardware to implement photosensitive control, which can reduce circuit cost and power consumption. Attached Figure Description

[0020] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements / modules and steps with the same reference numerals in the drawings are represented as similar elements / modules and steps. Unless otherwise stated, the figures in the drawings do not constitute a limitation on scale.

[0021] Figure 1 This is a schematic diagram of the structure of a photosensitive control circuit provided in an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the circuit structure of a photosensitive control circuit provided in an embodiment of the present invention. Detailed Implementation

[0023] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0024] To facilitate understanding of this application, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the application. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0025] It should be noted that, unless there is a conflict, the various features in the embodiments of this invention can be combined with each other, all of which are within the protection scope of this application. Furthermore, although functional modules are divided in the device schematic diagram, in some cases, they can be divided differently from those in the device. In addition, the terms "first," "second," etc., used herein do not limit the data or execution order, but only distinguish identical or similar items with substantially the same function and effect.

[0026] This invention provides a photosensitive control circuit; please refer to [link / reference]. Figure 1 The photosensitive control circuit 100 includes: a photosensitive detection unit 10, a first switching unit 20, a first energy storage unit 30, and a second switching unit 40.

[0027] The first end of the photosensitive detection unit 10 is connected to the first power supply 200, and the second end of the photosensitive detection unit 10 is connected to the first end of the second switching unit 40. The photosensitive detection unit 10 is used to generate a first signal to the second switching unit 40 based on the ambient light intensity. The second end of the second switching unit 40 is connected to the first power supply 200, and the third end of the second switching unit 40 is connected to the first end of the first energy storage unit 30. The second switching unit 40 is used to conduct the connection between the second end of the second switching unit 40 and the third end of the second switching unit 40 based on the first signal, so that the first energy storage unit 30 operates in [the specified state]. Charging state; the second end of the first energy storage unit 30 is connected to the first end of the first switching unit 20. When the first energy storage unit 30 is in the charging state, it outputs a second signal to the first switching unit 20. The second end of the first switching unit 20 is connected to the first power supply 200, and the third end of the first switching unit 20 is connected to the output terminal 300. When the second signal meets the preset conduction condition of the first switching unit 20, the first switching unit 20 conducts the connection between the second end and the third end of the first switching unit 20, so that the first power supply 200 is connected to the output terminal 300.

[0028] Specifically, the first power supply 200 can be either a DC power supply or an AC power supply. When the first power supply 200 is an AC power supply, it can be connected to the photosensitive control circuit through a rectifier unit. In practice, the first power supply and its voltage can be selected according to the requirements of the photosensitive control circuit, thereby adapting to a wide voltage input range. In the following description, a DC power supply is used as the first power supply, but this is not limited in actual applications. The output terminal 300 can be used to connect to external circuits, such as loads. The preset conduction condition of the second switching unit 20 is the magnitude of the second signal that enables the second switching unit 20 to conduct.

[0029] When the photosensitive control circuit 100 is connected to the first power supply 200 and the output terminal 300 respectively, the photosensitive detection unit 10 can be used to detect the ambient light intensity and generate a first signal to the second switching unit 40 according to the ambient light intensity.

[0030] When the first signal is lower than the conduction threshold of the second switching unit 40, the second switching unit 40 will connect the second terminal of the second switching unit 40 and the third terminal of the second switching unit 40. In this way, the first power supply 200 will enable the first energy storage unit 30 to operate in a charging state through the second switching unit 40. Then, the first energy storage unit 30 outputs a second signal to the first switching unit 20. Then, when the second signal meets the preset conduction condition of the first switching unit 20, the first switching unit 20 connects the second terminal of the first switching unit 20 and the third terminal of the first switching unit 20, so that the first power supply 200 is connected to the output terminal 300 through the first switching unit 20, thereby allowing the output terminal 300 to obtain the voltage signal of the first power supply 200.

[0031] When the first signal is greater than or equal to the conduction threshold of the second switching unit 40, the second switching unit 40 will disconnect the connection between the second terminal and the third terminal of the second switching unit 40. In this way, the first power supply 200 cannot charge the first energy storage unit 30, the first energy storage unit 30 cannot output the second signal to the first switching unit 20, and the first power supply 200 cannot connect to the output terminal 300 through the first switching unit 20.

[0032] As can be seen, in this photosensitive control circuit, photosensitive control can be achieved using pure hardware circuitry. Compared with using a microcontroller in conjunction with an integrated chip for photosensitive control, this embodiment can reduce detection costs, design costs, and power consumption, and can meet the design requirements of low-cost and low-power products.

[0033] In some of these embodiments, please refer to Figure 2 The photosensitive detection unit 10 includes a photodiode D4 and a voltage divider module 11; the cathode of the photodiode D4 is connected to the first power supply, the anode of the photodiode D4 is connected to the first terminal of the voltage divider module 11, the second terminal of the voltage divider module 11 is connected to the first terminal of the second switching unit 40, and the third terminal of the voltage divider module 11 is grounded.

[0034] Among them, the photodiode D4 is a semiconductor device that converts light signals into electrical signals, and it operates under reverse voltage. When there is no light, the reverse current of the photodiode D4 is very small, generally less than 0.1uA, also known as dark current. When there is light, the reverse current of the photodiode D4 is very large, also known as photocurrent. Therefore, for the photosensitive detection unit 10, when the ambient light is strong, such as during the day or at night when there are lights, the photodiode D4 receives a large light intensity and exhibits a low-resistance state. At this time, the current of the photodiode D4 is large. Then, the first power supply outputs a voltage signal higher than the conduction threshold of the second switching unit 40 through the voltage divider module 11 to the second switching unit 40, so that the second switching unit 40 is turned off. When there is no light or the ambient light is weak, the light intensity received by the photodiode D4 is small, and it exhibits a high resistance state. At this time, the current of the photodiode D4 is small. Then, the first power supply will output a voltage signal lower than the conduction threshold of the second switching unit 40 through the voltage divider module 11 to the second switching unit 40. Alternatively, the voltage divider module 11 can directly ground the first terminal of the second switching unit 40, so that the second switching unit 40 is turned on.

[0035] In some of these embodiments, please continue to refer to Figure 2The voltage divider module 11 includes a first voltage divider resistor Rf1 and a second voltage divider resistor Rf2. The first terminal of the first voltage divider resistor Rf1 is connected to the anode of the photodiode D4, and the second terminal of the first voltage divider resistor Rf1 is connected to the first terminal of the first switching unit 20 and the first terminal of the second voltage divider resistor Rf2. The second terminal of the second voltage divider resistor Rf2 is grounded. Thus, by setting the resistance values ​​of the first voltage divider resistor Rf1 and the second voltage divider resistor Rf2 according to the conduction threshold of the second switching unit 40, the first voltage divider resistor Rf1 and the second voltage divider resistor Rf2 can divide the first power supply according to the current of the photodiode D4, and output a suitable voltage signal to the second switching unit 40 when it needs to be turned on or off. In practical applications, the number and resistance values ​​of the voltage divider resistors in the voltage divider module 11 can be set according to actual needs and are not limited here.

[0036] In some embodiments, the first switching unit includes a first switching transistor and a second switching transistor; a first end of the first switching transistor is used to connect to a first power supply, a second end of the first switching transistor is connected to the first end of the second switching transistor, a third end of the first switching transistor is used to connect to an output terminal, a second end of the second switching transistor is connected to the second end of the first energy storage unit, and a third end of the second switching transistor is grounded.

[0037] For details, please refer to Figure 2 The first switching transistor includes a PMOS transistor Q1, and the second switching transistor includes an NPN transistor Q2. The drain of the PMOS transistor Q1 is connected to the first power supply, the source of the PMOS transistor Q1 is connected to the output terminal, the gate of the PMOS transistor Q1 is connected to the collector of the NPN transistor Q2, the base of the NPN transistor Q2 is connected to the second terminal of the first energy storage unit 30, and the emitter of the NPN transistor Q2 is grounded. In the first switching unit 20, when the first energy storage unit 30 is charging, since the voltage across the first energy storage unit 30 cannot change abruptly, the voltage at the second terminal of the first energy storage unit 30 cannot instantly drop below the conduction threshold of the NPN transistor Q2. That is, during the charging process of the first energy storage unit 30, the second terminal of the first energy storage unit 30 will generate a voltage higher than the conduction threshold of the NPN transistor Q2, such as a voltage higher than 0.7V. At this time, the NPN transistor Q2 will be turned on, the gate of the PMOS transistor Q1 will be grounded, and the PMOS transistor Q1 will also be turned on. The first power supply can be connected to the output terminal through the PMOS transistor Q1. In practical applications, the number of switching transistors, the type of switching transistors, and the conduction threshold of the switching transistors included in the first switching unit 20 can all be set according to actual needs, and are not limited to the limitations of this embodiment.

[0038] To improve the stability of circuit operation, in some embodiments please refer to Figure 2The first switching unit also includes a first resistor R1; the first resistor R1 is connected between the first terminal and the second terminal of the first switching transistor. For details, please refer to [link to details]. Figure 2 The first resistor R1 is connected between the drain and gate of PMOS transistor Q1. In this way, when the gate voltage of PMOS transistor Q1 is unstable, the first power supply can pull up the gate voltage of PMOS transistor Q1 through the first resistor R1, thus turning off PMOS transistor Q1 and ensuring that PMOS transistor Q1 is reliably turned off, thereby improving the stability of circuit operation.

[0039] To improve the safety of circuit operation, in some embodiments please refer to Figure 2 The first switching unit 20 also includes a second resistor R2; the second resistor R2 is connected between the second terminal of the first switching transistor and the first terminal of the second switching transistor. For details, please refer to [link to relevant documentation]. Figure 2 The second resistor R2 is connected between the gate of the PMOS transistor Q1 and the collector of the NPN transistor Q2. In this way, when the first power supply changes abruptly, the second resistor R2 can act as an isolation device and limit the current flowing through the collector of the NPN transistor Q2, thereby protecting the NPN transistor Q2 from damage by the sudden voltage change and improving the safety and reliability of the circuit operation.

[0040] In some embodiments, the second switching unit includes a third switching transistor; the first end of the third switching transistor is connected to the first power supply, the second end of the third switching transistor is connected to the second end of the photosensitive detection unit, and the third end of the third switching transistor is connected to the first end of the first energy storage unit.

[0041] For details, please refer to Figure 2 The third switching transistor includes a PNP transistor Q3. The emitter of PNP transistor Q3 is connected to the first power supply, the base of PNP transistor Q3 is connected to the second terminal of the first voltage divider resistor Rf1, and the collector of PNP transistor Q3 is connected to the first terminal of the first energy storage unit 30. Thus, when the photosensitive detection unit 10 outputs a voltage signal higher than 0.7V, PNP transistor Q3 is turned on, and the first power supply charges the first energy storage unit 30 through PNP transistor Q3; when the photosensitive detection unit 10 outputs a voltage signal lower than 0.7V, PNP transistor Q3 is turned off, and the first power supply cannot charge the first energy storage unit 30. In practical applications, the number, type, and on-threshold of the switching transistors in the second switching unit 40 can be set according to actual needs, and are not limited to the limitations of this embodiment.

[0042] In some embodiments, the second switching unit 40 further includes a third resistor R3; the third resistor R3 is connected between the third terminal of the third switching transistor and ground. For details, please refer to [link to relevant documentation]. Figure 2The third resistor R3 is placed between the collector of the PNP transistor Q3 and ground. By setting this third resistor R3, the current flowing through the PNP transistor Q3 can be limited, thereby protecting the PNP transistor Q3 and improving the safety and reliability of the circuit operation. Typically, the value of the third resistor R3 is quite large, for example, a 2MΩ resistor. When the PNP transistor Q3 is conducting, it can act as an isolation device and prevent short circuits, thus improving circuit safety.

[0043] In some of these embodiments, please refer to Figure 2 The first energy storage unit 30 includes a first capacitor C1 and a fourth resistor R4; the first end of the first capacitor C1 is connected to the third end of the second switching unit 40, the second end of the first capacitor C1 is connected to the first end of the first switching unit 20 and the first end of the fourth resistor R4, and the second end of the fourth resistor R4 is grounded.

[0044] Specifically, the first terminal of the first capacitor C1 is connected to the collector of the PNP transistor Q3 and the third resistor R3. The second terminal of the second capacitor C2 is connected to the base of the NPN transistor Q2 and the first terminal of the fourth resistor R4. Typically, the fourth resistor R4 has a relatively large resistance. Thus, when the PNP transistor Q3 is turned on, the third resistor R3 divides the first power supply, and the first power supply charges the first capacitor C1 through the PNP transistor Q3. Since the first capacitor C1 isolates the DC power supply, its second terminal also charges. When the resistance of the fourth resistor R4 is relatively large, the voltage at the second terminal of the first capacitor C1 cannot instantly drop below 0.7V, resulting in a voltage higher than 0.7V at the second terminal of the first capacitor C1. This outputs a voltage higher than 0.7V to the base of the NPN transistor Q2, turning on the NPN transistor Q2 and consequently turning on the PMOS transistor Q1. Typically, the first capacitor C1 can be a film capacitor, with the first terminal being the positive terminal and the second terminal being the negative terminal.

[0045] Understandably, the detection signal of the photosensitive detection unit 10 will change due to the influence of light intensity, causing the operating state of the photosensitive control circuit to change. If the trigger circuit is turned on at night when there is no light, and the photosensitive detection unit is suddenly exposed to strong light, the circuit will be triggered to turn off. Then, when the strong light disappears, the circuit will be triggered to turn on again. In this situation, the circuit is in an unstable conducting state, which reduces the user experience. To improve the user experience, in some embodiments, please refer to... Figure 2 The photosensitive control circuit also includes a second energy storage unit 50; the first end of the second energy storage unit 50 is connected to the third end of the first switching unit 20, and the second end of the second energy storage unit 50 is connected to the first end of the first switching unit 20.

[0046] In this way, when the first switching unit 20 is turned on, the first power supply can charge the second energy storage unit 50 through the first switching unit 20. When the second switching unit 40 is in an unstable conducting state, the first energy storage unit 30 may not be able to be charged. At this time, the energy stored in the second energy storage unit 50 will be released and a voltage signal will be output to the third terminal of the first switching unit 20, so that the first switching unit 20 can continue to maintain the conducting state. This can stabilize the conducting state of the circuit, extend the working time of the subsequent circuit, and improve the user experience.

[0047] In some of these embodiments, please continue to refer to Figure 2 The second energy storage unit 50 includes a second capacitor C2; the first terminal of the second capacitor C2 is connected to the third terminal of the first switching unit 20, and the second terminal of the second capacitor C2 is connected to the first terminal of the first switching unit 20. For details, please refer to [link to relevant documentation]. Figure 2 The first terminal of the second capacitor C2 is connected to the source of the PMOS transistor Q1, and the second terminal of the second capacitor C2 is connected to the base of the NPN transistor Q2, the second terminal of the first capacitor C1, and the first terminal of the fourth resistor R4. When the PMOS transistor Q1 is turned on, the first power supply charges the second capacitor C2. When the first capacitor C1 cannot output a voltage signal to turn on the NPN transistor Q2, that is, when the PMOS transistor Q1 is turned off, the second capacitor C2 discharges. In this way, the second capacitor C2 will output a voltage signal higher than that of the NPN transistor Q2 to the base of the NPN transistor Q2, so that the NPN transistor Q2 continues to conduct, thereby allowing the PMOS transistor Q1 to continue to conduct, thus stabilizing the conduction state of the circuit and extending the conduction time of the PMOS transistor Q1.

[0048] In some of these embodiments, please refer to Figure 2 The photosensitive control circuit also includes a first diode D1; the anode of the first diode D1 is connected to the second terminal of the second energy storage unit 50, and the cathode of the first diode D1 is connected to the first terminal of the first switching unit 20. Specifically, the anode of the first diode D1 is connected to the second terminal of the second capacitor C2, and the cathode of the first diode D1 is connected to the second terminal of the first capacitor C1, the base of the NPN transistor Q2, and the first terminal of the fourth resistor R4. In this way, by utilizing the unidirectional conduction of the first diode D1, the voltage of the first capacitor C1 and the second capacitor C2 is prevented from being connected in series, and finally, the voltage of the first capacitor C1 and the second capacitor C2 is discharged through the fourth resistor R4, ensuring the stability and safety of the circuit operation.

[0049] In some of these embodiments, please refer to Figure 2The photosensitive control circuit also includes a second diode D2; the cathode of the second diode D2 is connected to the second terminal of the second energy storage unit 50, and the anode of the second diode D2 is grounded. Specifically, the cathode of the second diode D2 is connected to the second terminal of the second capacitor C2 and the anode of the first diode D1, respectively, and the anode of the second diode D2 is grounded. Since the ground voltage is a small floating voltage, generally below 0.7V, during the discharge of the second capacitor C2, there may be a situation where the voltage at the second terminal of the second capacitor C2 is lower than the ground voltage. At this time, the second diode D2 conducts, stably grounding the second terminal of the second capacitor C2 and discharging the voltage of the second capacitor C2 to the ground voltage, thereby ensuring the safety of the circuit.

[0050] During the process of the second diode D2 discharging the second capacitor C2, in order to ensure the safety of the circuit operation, in some embodiments, please continue to refer to... Figure 2 The photosensitive control circuit also includes a fifth resistor R5, which is connected between the anode of the second diode D2 and ground. By setting the fifth resistor R5, the current of the second capacitor C2 when it discharges through the second diode D2 can be limited, thus ensuring the safety of the circuit.

[0051] To improve the user experience, in some embodiments please refer to Figure 2 The photosensitive control circuit also includes a button SW1. The first end of button SW1 is connected to a first power supply, and the second end of button SW1 is connected to the first end of the first switching unit 20. Specifically, the second end of button SW1 is connected to the base of NPN transistor Q2. Button SW1 is a physical button; when pressed, the connection between the first and second ends of button SW1 is established. Thus, in case of emergency power supply, button SW1 can be pressed. When button SW1 is pressed, the first power supply is connected to the base of NPN transistor Q2 through button SW1, causing the base of NPN transistor Q2 to reach a high level, thereby turning on NPN transistor Q2 and PMOS transistor Q1. The first power supply can then power the subsequent circuit, achieving the function of emergency power supply and improving the user experience.

[0052] In some embodiments, the photosensitive control circuit further includes an input port U1, the first end of which is connected to the first end of the photosensitive detection unit 10, the second end of the first switching unit 20, and the second end of the second switching unit 40, respectively, and the second end of the input port U1 is grounded; the input port U1 is used to connect to the first power supply.

[0053] In some embodiments, the photosensitive control circuit further includes an output port U2, the first end of which is connected to the third end of the first switching unit 20, and the second end of which is grounded. The output port U2 is used to connect to the output terminal.

[0054] In some embodiments, the photosensitive control circuit further includes a light-emitting unit 60. The first end of the light-emitting unit 60 is connected to the third end of the first switching unit 20, and the second end of the light-emitting unit 60 is grounded. Specifically, the light-emitting unit 60 includes a light-emitting diode D3. The anode of the light-emitting diode D3 is connected to the source of the PMOS transistor Q1, and the cathode of the light-emitting diode D3 is grounded. Thus, when the first switching unit 20 is triggered and turned on, the first power supply can form a loop through the PMOS transistor Q1, the light-emitting diode D3, and ground, thereby powering the light-emitting diode D3 and causing it to emit light.

[0055] In order to limit the current flowing through the light-emitting diode D3, in some embodiments, the light-emitting unit 60 further includes a sixth resistor R6, which is connected between the source of the PMOS transistor Q1 and the anode of the light-emitting diode D3. In this way, when the PMOS transistor Q1 is triggered to conduct, the sixth resistor R6 can limit the current flowing through the light-emitting diode D3 from the first power supply, thereby protecting the light-emitting diode D3 and improving the safety and reliability of the circuit operation.

[0056] In some embodiments, a high-level signal can be output at the anode of LED D3 to other circuit modules. For example, the anode of LED D3 can also be connected to a control unit. Thus, after the PMOS transistor is turned on, the photosensitive control circuit can output a high-level signal to the control unit through the anode of LED D3, allowing the control unit to operate based on this high-level signal. In practical applications, a voltage divider module can also be connected to the third terminal of the first switching unit, and then other circuit modules can be connected through the voltage divider module. Similarly, after the first switching unit is turned on, a suitable signal can be output to other circuit modules through the voltage divider module to achieve other functional requirements. In practice, the configuration can be adjusted according to actual needs and is not limited here.

[0057] The following is combined Figure 2 The embodiments shown illustrate in detail the specific working process of the photosensitive control circuit provided in the embodiments of the present invention.

[0058] When the input port U1 is connected to the first power supply, the photodiode D4 starts to work. When the ambient light is strong, such as during the day or at night when there are lights, the photodiode D4 receives a large amount of light and exhibits a low resistance state. At this time, the current of the photodiode D4 is large. Then, the first power supply is divided by the photodiode D4, the first voltage divider resistor Rf1, and the second voltage divider resistor Rf2. The second terminal of the first voltage divider resistor Rf1 outputs a voltage signal higher than 0.7V to the base of the PNP transistor Q3. The PNP transistor Q3 is stably turned off, and the subsequent circuit does not work.

[0059] When there is no light or the ambient light is weak, the light intensity received by the photodiode D4 is small, resulting in a high-resistance state. At this time, the current of the photodiode D4 is small. Then, the first power supply is divided by the photodiode D4, the first voltage divider resistor Rf1, and the second voltage divider resistor Rf2. The second terminal of the first voltage divider resistor Rf1 outputs a voltage signal lower than 0.7V to the base of the PNP transistor Q3, turning on the PNP transistor Q3. Alternatively, the base of the PNP transistor Q3 is grounded through the second voltage divider resistor Rf2, turning on the PNP transistor Q3.

[0060] Then, when PNP transistor Q3 is turned on, on the one hand, the first power supply is divided by PNP transistor Q3 and third resistor R3. On the other hand, the first power supply also forms a circuit through PNP transistor Q3, first capacitor C1, fourth resistor R4 and ground, so that the first power supply charges the first capacitor C1. Since the voltage across the first capacitor C1 cannot change abruptly, the voltage at the second terminal of the first capacitor C1 cannot drop below 0.7V instantaneously. Therefore, a voltage higher than 0.7V will be generated at the second terminal of the first capacitor C1. After the base of NPN transistor Q2 receives this voltage signal, NPN transistor Q2 turns on. The gate of PMOS transistor Q1 will be grounded through second resistor R2 and NPN transistor Q2, and PMOS transistor Q1 turns on.

[0061] When PMOS transistor Q1 is turned on, firstly, when output port U2 is connected to the output terminal, the first power supply outputs a voltage signal to the output terminal through PMOS transistor Q1, which can, for example, provide power to the output terminal.

[0062] Secondly, when the light-emitting unit 60 is provided, the first power supply forms a circuit through the PMOS transistor Q1, the sixth resistor R6, the light-emitting diode D3, and ground, and the light-emitting diode D3 emits light. Additionally, if the anode of the light-emitting diode D3 is connected to another circuit module, a voltage signal can be output to that other circuit module through the anode of the light-emitting diode D3. In practical applications, other voltage divider modules 11 can also be set up to output appropriate voltage signals to other circuit modules; this is not limited here.

[0063] Finally, the first power supply also charges the second capacitor C2 through the PMOS transistor Q1. When the temperature detection unit is unstable, the conduction state of the PNP transistor Q3 is unstable, that is, the conduction state of the NPN transistor Q2 is unstable. The electrical energy stored in the second capacitor C2 can provide a stable voltage for the NPN transistor Q2, thereby making the NPN transistor Q2 conduct stably and the PMOS transistor Q1 conduct stably, thus ensuring the stability of the circuit operation and extending the circuit operation time.

[0064] Therefore, the photosensitive control circuit can sense the intensity of natural light and realize the function of controlling the circuit switch by the intensity of light. Since photosensitive control can be realized by using a pure hardware circuit, compared with using a microcontroller and integrated chip for photosensitive control, this embodiment can reduce detection cost, design cost and power consumption, and can meet the design requirements of low-cost products and low-power products.

[0065] Secondly, embodiments of the present invention also provide an electrical appliance that includes a photosensitive control circuit as described in any of the first aspects. Specifically, the electrical appliance can be a light-controlled lamp, a light-controlled switch, a light-controlled display, or any other suitable light-controlled device. This electrical appliance uses a purely hardware circuit to achieve photosensitive control, reducing circuit cost and power consumption.

[0066] This invention provides a photosensitive control circuit and electrical appliance, including a photosensitive detection unit, a first switching unit, a first energy storage unit, and a second switching unit. The photosensitive detection unit generates a first signal to the second switching unit based on the ambient light intensity. When the first signal is lower than the conduction threshold of the second switching unit, the second switching unit connects its second and third terminals, allowing a first power source to charge the first energy storage unit. Then, the first energy storage unit outputs a second signal to the first switching unit. Next, the first switching unit connects its second and third terminals, connecting the first power source to its output terminal, thus allowing the output terminal to receive the voltage signal from the first power source. This circuit uses pure hardware to implement photosensitive control, reducing circuit cost and power consumption.

[0067] It should be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; under the concept of the present invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the present invention as described above, which are not provided in detail for the sake of brevity; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A photosensitive control circuit, characterized in that, include: A photosensitive detection unit, a first switching unit, a first energy storage unit, and a second switching unit; The first end of the photosensitive detection unit is used to connect to the first power supply, the second end of the photosensitive detection unit is connected to the first end of the second switching unit, and the photosensitive detection unit is used to generate a first signal to the second switching unit according to the ambient light intensity. The second end of the second switching unit is used to connect to the first power source, and the third end of the second switching unit is connected to the first end of the first energy storage unit. The second switching unit is used to conduct the connection between the second end of the second switching unit and the third end of the second switching unit according to the first signal, so that the first energy storage unit works in a charging state. The second end of the first energy storage unit is connected to the first end of the first switching unit. When the first energy storage unit is in the charging state, it outputs a second signal to the first switching unit. The second end of the first switching unit is used to connect to the first power supply, and the third end of the first switching unit is used to connect to the output terminal. When the second signal satisfies the preset conduction condition of the first switching unit, the first switching unit is used to conduct the connection between the second end of the first switching unit and the third end of the first switching unit, so that the first power supply is connected to the output terminal.

2. The photosensitive control circuit according to claim 1, characterized in that, The photosensitive control circuit also includes a second energy storage unit; The first end of the second energy storage unit is connected to the third end of the first switching unit, and the second end of the second energy storage unit is connected to the first end of the first switching unit.

3. The photosensitive control circuit according to claim 2, characterized in that, The photosensitive control circuit also includes buttons; The first end of the button is used to connect to the first power source, and the second end of the button is connected to the first end of the first switch unit.

4. The photosensitive control circuit according to claim 3, characterized in that, The photosensitive control circuit also includes a first diode; The anode of the first diode is connected to the second terminal of the second energy storage unit, and the cathode of the first diode is connected to the first terminal of the first switching unit.

5. The photosensitive control circuit according to claim 4, characterized in that, The photosensitive control circuit also includes a second diode; The cathode of the second diode is connected to the second terminal of the second energy storage unit, and the anode of the second diode is grounded.

6. The photosensitive control circuit according to any one of claims 1-5, characterized in that, The photosensitive detection unit includes a photodiode and a voltage divider module; The cathode of the photodiode is connected to the first power supply, the anode of the photodiode is connected to the first terminal of the voltage divider module, the second terminal of the voltage divider module is connected to the first terminal of the second switching unit, and the third terminal of the voltage divider module is grounded.

7. The photosensitive control circuit according to any one of claims 1-5, characterized in that, The first switching unit includes a first switching transistor and a second switching transistor; The first end of the first switching transistor is used to connect to the first power supply, the second end of the first switching transistor is connected to the first end of the second switching transistor, the third end of the first switching transistor is used to connect to the output terminal, the second end of the second switching transistor is connected to the second end of the first energy storage unit, and the third end of the second switching transistor is grounded.

8. The photosensitive control circuit according to claim 7, characterized in that, The first switching unit further includes a first resistor and a second resistor; The first resistor is connected between the first terminal of the first switching transistor and the second terminal of the first switching transistor, and the second resistor is connected between the second terminal of the first switching transistor and the first terminal of the second switching transistor.

9. The photosensitive control circuit according to any one of claims 1-5, characterized in that, The second switching unit includes a third switching transistor; The first end of the third switch is connected to the first power supply, the second end of the third switch is connected to the second end of the photosensitive detection unit, and the third end of the third switch is connected to the first end of the first energy storage unit.

10. The photosensitive control circuit according to claim 9, characterized in that, The second switching unit also includes a third resistor; The third resistor is connected between the third terminal of the third switch and ground.

11. The photosensitive control circuit according to any one of claims 1-5, characterized in that, The first energy storage unit includes a first capacitor and a fourth resistor; The first terminal of the first capacitor is connected to the third terminal of the second switching unit, the second terminal of the first capacitor is connected to the first terminal of the first switching unit and the first terminal of the fourth resistor, and the second terminal of the fourth resistor is grounded.

12. The photosensitive control circuit according to any one of claims 2-5, characterized in that, The second energy storage unit includes a second capacitor; The first end of the second capacitor is connected to the third end of the first switching unit, and the first end of the second capacitor is connected to the first end of the first switching unit.

13. The photosensitive control circuit according to any one of claims 1-5, characterized in that, The photosensitive control circuit also includes an input port and an output port; The first end of the input port is connected to the first end of the photosensitive detection unit, the second end of the first switching unit, and the second end of the second switching unit, respectively. The second end of the input port is grounded. The input port is used to connect to the first power supply. The first end of the output port is connected to the third end of the first switch unit, and the second end of the output port is grounded. The output port is used to connect to the output terminal.

14. The photosensitive control circuit according to any one of claims 1-5, characterized in that, The photosensitive control circuit further includes a light-emitting unit, the first end of which is connected to the third end of the first switching unit, and the second end of which is grounded.

15. An electrical appliance, characterized in that, Includes the photosensitive control circuit as described in any one of claims 1-14.

Images