Light-operated switch control circuit and control method thereof

Abstract

The invention discloses a light-operated switch control circuit and a control method thereof. The light-operated switch control circuit comprises a power supply, a first electric control switch, a first photosensitive element, a triode and a control chip, the first end of the first photosensitive element is electrically connected with a power supply through a resistor, and the second end of the first photosensitive element is grounded; one end of the first electric control switch is electrically connected with a power supply, and the other end of the first electric control switch is electrically connected with a collector of the triode; a first pin of the control chip is electrically connected with a power supply, and a second pin of the control chip is electrically connected with a base electrode of the triode; the first end of the first photosensitive element is also electrically connected with a third pin of the control chip; the third pin of the control chip is used for acquiring the voltage of the first end of the first photosensitive element; a fourth pin of the control chip is electrically connected to a circuit between the first end of the first photosensitive element and a third pin of the control chip through a resistor; and the second photosensitive element is arranged outside. According to the invention, frequent automatic switching can be avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of light-controlled circuits, and in particular to a light-controlled switch control circuit and a control method thereof. Background Art

[0002] Lamps are widely used in places that need lighting, such as outdoor and indoor. Indoor lamps are usually controlled by touch switches or remote controls, and are often not affected by day or night. Outdoor lamps (garden lights, lawn lights, street lights, etc.) are closely related to the lighting conditions of day and night. For energy-saving considerations, outdoor lamps need to be turned off during the day and turned on at night. Since there is light during the day and no light at night, it is possible to distinguish between day and night. Therefore, outdoor lamps can be turned off during the day and turned on at night through light-controlled switches.

[0003] However, when the lamp is turned on, its own light affects the photosensor inside it, which can easily cause the photosensor to trigger daytime conditions to turn off the lamp, and then trigger it to turn on again after the light is turned off, resulting in a flashing cycle of automatic switching, which affects the life of the lamp and causes poor lighting effects. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a light-operated switch control circuit and a control method thereof, which can avoid frequent automatic switching; and also provide a second photosensitive element arranged outside.

[0005] In order to solve the above technical problems, the first aspect of the present invention discloses a light-operated switch control circuit, including a power supply, a first electric-controlled switch, a first photosensitive element, a triode, and a control chip;

[0006] The first end of the first photosensitive element is electrically connected to the power supply via a resistor, and the second end of the first photosensitive element is grounded;

[0007] One end of the first electronically controlled switch is electrically connected to the power supply, the other end of the first electronically controlled switch is electrically connected to the collector of the transistor, and the emitter of the transistor is grounded;

[0008] The first pin of the control chip is electrically connected to the power supply, and the second pin of the control chip is electrically connected to the base of the transistor;

[0009] The first end of the first photosensitive element is also electrically connected to the third pin of the control chip; the third pin of the control chip is used to obtain the voltage of the first end of the first photosensitive element; the fourth pin of the control chip is electrically connected to the line between the first end of the first photosensitive element and the third pin of the control chip via a resistor.

[0010] As an optional implementation, the first photosensitive element is a photoresistor, a photodiode or a phototransistor.

[0011] As another optional implementation, the fourth pin is further connected in series with a first resistor, and the fourth pin is connected to the first end of the first photosensitive element via the first resistor.

[0012] As another optional implementation, the light-operated switch control circuit is installed in a housing, and further includes a second photosensitive element arranged outside the housing, the second photosensitive element being used to directly sense the external light intensity;

[0013] The first end of the second photosensitive element is electrically connected to the power supply via a resistor, and the second end of the second photosensitive element is grounded; the fifth pin of the control chip is electrically connected to the line between the first end of the second photosensitive element and the power supply; the fifth pin of the control chip is used to obtain the voltage of the first end of the second photosensitive element.

[0014] As another optional implementation, the power source is alternating current, and further includes a rectifier module for converting the power source into direct current, a filter module, and a step-down chip for converting the direct current into direct current with a lower voltage value.

[0015] As another optional implementation, the first electrically controlled switch is a coil portion of a relay, and a switch portion of the relay is connected to a power supply line of a controlled object.

[0016] A second aspect of the present invention discloses a control method for the light-operated switch control circuit according to the first aspect of the present invention, the control method comprising:

[0017] Acquire the voltage value of the third pin of the control chip in real time;

[0018] Determine whether the voltage value of the third pin of the control chip is higher than the first preset voltage, and if so, adjust the potential of the second pin of the control chip to a voltage value that turns on the transistor;

[0019] It is determined whether the voltage value of the third pin of the control chip is lower than the second preset voltage. If it is determined to be yes, the potential of the second pin of the control chip is adjusted to a voltage value that cuts off the transistor.

[0020] As an optional implementation, the control method further includes:

[0021] When the voltage value of the third pin of the control chip reaches the first preset voltage, the output of the second pin is adjusted to a high potential, and the voltage value of the third pin is detected within a preset time length; wherein, when the voltage value of the third pin is detected to be lower than the first preset voltage within the preset time length, the voltage value of the third pin at this time is obtained as a recorded value, and the output of the fourth pin is adjusted to a high potential;

[0022] When the voltage value of the third pin decreases by at least a preset voltage value based on the recorded value, the potential of the second pin is adjusted to a voltage value that cuts off the transistor.

[0023] The third aspect of the present invention discloses another control method, which is used in the partial light-operated switch control circuit according to the first aspect of the present invention, and the method comprises:

[0024] When the light-operated switch control circuit is connected to only the first photosensitive element, the output voltage of the second pin is controlled according to the voltage value of the third pin;

[0025] When the light-operated switch control circuit is connected to the first photosensitive element and the second photosensitive element at the same time, the voltage values ​​of the third pin and the fifth pin of the control chip are obtained in real time, the voltage value change of the fifth pin and the voltage value change of the third pin within a preset time length are calculated, and the magnitudes of the two changes are determined;

[0026] Among them, when the change in the voltage value of the fifth pin within the preset time length is greater than the change in the voltage value of the third pin, the output voltage of the second pin is controlled according to the voltage value of the fifth pin; when the change in the voltage value of the fifth pin within the preset time length is less than the change in the voltage value of the third pin, the output voltage of the second pin is controlled according to the voltage value of the third pin.

[0027] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0028] The embodiment of the present invention detects in real time whether flickering occurs through the detection pin of the chip. When this occurs, the voltage of the detection pin is additionally increased so that the voltage of the detection pin is no longer at the critical condition for shutdown, thereby avoiding frequent switching operations. Since only the shutdown voltage threshold is increased, the normal shutdown operation during the day will not be affected under higher light levels during the day. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 It is a structural schematic diagram of a light-operated switch control circuit disclosed in an embodiment of the present invention;

[0031] Figure 2 It is a flow chart of a control method of a light-operated switch control circuit disclosed in an embodiment of the present invention;

[0032] Figure 3 It is a flow chart of another control method of a light-operated switch control circuit disclosed in an embodiment of the present invention;

[0033] Figure 4 It is a flow chart of another control method of a light-operated switch control circuit disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0034] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] Embodiment 1

[0036] See also Figure 1 , the embodiment of the present invention discloses a light-operated switch control circuit, including a power supply AC, a first electric-controlled switch RLY1, a first photosensitive element PT1, a transistor Q2, and a control chip U2;

[0037] A first end of the first photosensitive element PT1 is electrically connected to the power source AC via a resistor R2, and a second end of the first photosensitive element PT1 is grounded;

[0038] One end of the first electronically controlled switch RLY1 is electrically connected to the power source AC, the other end of the first electronically controlled switch RLY1 is electrically connected to the collector of the transistor Q2, and the emitter of the transistor Q2 is grounded;

[0039] The first pin 1 of the control chip U2 is electrically connected to the power source AC, and the second pin 2 of the control chip U2 is electrically connected to the base of the transistor Q2;

[0040] The first end of the first photosensitive element PT1 is also electrically connected to the third pin 3 of the control chip U2; the third pin 3 of the control chip U2 is used to obtain the voltage of the first end of the first photosensitive element PT1; the fourth pin 4 of the control chip U2 is electrically connected to the line between the first end of the first photosensitive element PT1 and the third pin 3 of the control chip U2.

[0041] In the embodiment of the present invention, when it is dark, the equivalent resistance of the first photosensitive element PT1 increases, thereby increasing the voltage at its first end. When the control chip U2 detects that the voltage at the first end of the first photosensitive element PT1 is higher than the first preset voltage (for example, 1V) (that is, the light is dark enough, indicating that it is night), the control chip U2 adjusts the potential of the second pin 2 to a corresponding voltage value for turning on the transistor Q2. After turning on the transistor Q2, the collector of the transistor Q2 is grounded, so that there is current at both ends of the first electronically controlled switch RLY1, thereby starting the first electronically controlled switch RLY1; when the control chip U2 detects that the voltage at the first end of the first photosensitive element PT1 is lower than the second preset voltage (for example, 0.7V) (that is, the light is bright enough, indicating that it is daytime), the control chip U2 adjusts the potential of the second pin 2 to a corresponding voltage value for turning off the transistor Q2. After turning off the transistor Q2, there is no current at both ends of the first electronically controlled switch RLY1, thereby disconnecting the first electronically controlled switch RLY1.

[0042] In addition, when the first electrically controlled switch RLY1 is used to control the light, the first photosensitive element PT1 is affected by the light, and the light may be turned on because it is lower than the second preset voltage, and then turned on again because of darkness after the light is turned off, entering a flickering cycle. In this regard, when the voltage value of the third pin 3 of the control chip U2 reaches the first preset voltage, the output of the second pin 2 is adjusted to a high potential, and the voltage value of the third pin 3 is detected within a preset time. When it is detected that the voltage value of the third pin 3 is lower than the first preset voltage, the voltage value of the third pin 3 at this time is obtained as the recorded value, and the output of the fourth pin 4 is adjusted to a high potential, so that the positive voltage of the first photosensitive element PT1 rises a little; when the voltage value of the third pin 3 drops by at least the preset voltage value on the basis of the recorded value, the potential of the second pin 2 is adjusted to the voltage value that cuts off the transistor Q2, so that the light sensitivity needs to be stronger to turn off the first electrically controlled switch RLY1, thereby ensuring the stability of control and avoiding the frequent switching of the first electrically controlled switch RLY1.

[0043] In an optional embodiment, the first photosensitive element PT1 is a photoresistor, a photodiode or a phototransistor Q2.

[0044] In yet another optional embodiment, the fourth pin 4 is further connected in series with a first resistor R3, and the fourth pin 4 is connected to the first end of the first photosensitive element PT1 via the first resistor R3.

[0045] In another optional embodiment, the power source AC is alternating current, and further includes a rectifier module for converting the power source AC into direct current, a filter module, and a step-down chip U1 for converting the direct current into direct current with a lower voltage value.

[0046] by Figure 1 For example, in this embodiment, the rectifier module can be a half-wave rectifier (through Figure 1 The diode D2) can also be a full-wave rectifier. Figure 1 The step-down chip U1 converts the voltage into 3.3V (or other voltages such as 5V), and supplies power to the control chip U2 via pin 5. The filter module includes at least capacitors C1, C2, C4 and C5.

[0047] In yet another optional embodiment, the first electronically controlled switch RLY1 is a coil portion of a relay, and a switch portion of the relay is connected to a power supply line of a controlled object.

[0048] Embodiment 2

[0049] See also Figure 1 The embodiment of the present invention discloses a light-operated switch control circuit, which includes all the features of the light-operated switch control circuit in the first embodiment, except that:

[0050] The light-operated switch control circuit is installed in a housing, and further includes a second photosensitive element PT2 arranged outside the housing, the second photosensitive element being used to directly sense the external light intensity;

[0051] The first end of the second photosensitive element is electrically connected to the power supply AC via resistor R6, and the second end of the second photosensitive element is grounded; the fifth pin 5 of the control chip U2 is electrically connected to the line between the first end of the second photosensitive element and the power supply AC; the fifth pin 5 of the control chip U2 is used to obtain the voltage of the first end of the second photosensitive element.

[0052] Embodiment 3

[0053] See also Figure 2 The embodiment of the present invention discloses a control method for the light-operated switch control circuit as described in the first embodiment, the control method comprising:

[0054] 101. Obtain the voltage value of the third pin of the control chip U2 in real time.

[0055] 102. Determine whether the voltage value of the third pin of the control chip U2 is higher than the first preset voltage. If yes, adjust the potential of the second pin of the control chip U2 to a voltage value that turns on the transistor Q2.

[0056] 103. Determine whether the voltage value of the third pin of the control chip U2 is lower than the second preset voltage. If yes, adjust the potential of the second pin of the control chip U2 to a voltage value that cuts off the transistor Q2.

[0057] For example, the first preset voltage can be set to 1V, and the second preset voltage can be set to 0.7V. When the control chip U2 detects that the voltage at the first end of the first photosensitive element PT1 is higher than the first preset voltage and is not too close to the power supply voltage (lower than the power supply voltage within 0.2V), it means that the light is dark enough, and the light is immediately triggered to turn on; when the control chip U2 detects that the voltage at the first end of the first photosensitive element PT1 is lower than the second preset voltage, it means that the light is bright enough, and the light is immediately triggered to turn off; as long as the voltage of the first photosensitive element PT1 does not fall below 1V and is not too close to the power supply voltage after the light is turned on, the light can be turned off after dawn, ensuring that the light will not be turned off suddenly during the lighting period.

[0058] In an optional embodiment, the control method further includes:

[0059] When the voltage value of the third pin 3 of the control chip U2 reaches the first preset voltage, the output of the second pin 2 is adjusted to a high potential, and the voltage value of the third pin 3 is detected within a preset time length; wherein, when the voltage value of the third pin 3 is detected to be lower than the first preset voltage within the preset time length, the voltage value of the third pin 3 at this time is obtained as a recorded value, and the output of the fourth pin 4 is adjusted to a high potential;

[0060] When the voltage value of the third pin 3 drops by at least a preset voltage value based on the recorded value, the potential of the second pin 2 is adjusted to a voltage value that cuts off the transistor Q2.

[0061] For example, the preset voltage value can be set to 0.3 V. When the voltage at the first end of the first photosensitive element PT1 is lower than 0.2 V, the light will flicker. The voltage value is read, and pin 1 is made to output a high potential, so that the positive voltage of the photosensitive tube PT1 rises a little, and the light is turned off after the current voltage drops by 0.3 V, that is, the external light intensity is ensured to be large enough to achieve stable light off and avoid the light flickering again.

[0062] Embodiment 3

[0063] See also Figures 3-4 The embodiment of the present invention discloses a control method for the light-operated switch control circuit as described in the second embodiment, the control method comprising:

[0064] 201. When the light-operated switch control circuit is only connected to the first photosensor PT1, the output voltage of the second pin is controlled according to the voltage value of the third pin.

[0065] 301. When the light-operated switch control circuit is connected to the first photosensitive element PT1 and the second photosensitive element PT2 at the same time, the voltage values ​​of the third pin and the fifth pin of the control chip U2 are obtained in real time, the voltage value change of the fifth pin and the voltage value change of the third pin within a preset time length are calculated, and the magnitudes of the two changes are determined.

[0066] 302. When the voltage value change of the fifth pin within the preset time length is greater than the voltage value change of the third pin, the output voltage of the second pin is controlled according to the voltage value of the fifth pin; when the voltage value change of the fifth pin within the preset time length is less than the voltage value change of the third pin, the output voltage of the second pin is controlled according to the voltage value of the third pin.

[0067] For example, the first preset voltage may be set to 1V, and the second preset voltage may be set to 0.7V.

[0068] The first photosensitive element PT1 is arranged in a housing (such as a lamp housing), and the second photosensitive element PT2 is arranged outside the housing, such as outdoors. The detected light data is closer to the actual outdoor conditions than PT1. Therefore, in this embodiment, when PT2 is connected to the control circuit, the data of the second photosensitive element PT2 is preferentially used for control. Specifically, when the voltage value change of the second photosensitive element PT2 is greater than that of the first photosensitive element PT1, the data detected by the second photosensitive element PT2 shall prevail. Optional, Figure 1 The resistance values ​​of P2 and R6 can be equal.

[0069] The contents disclosed in the embodiments of the present invention only disclose the preferred embodiments of the present invention, which are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, it should be understood by those skilled in the art that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A light-operated switch control circuit, characterized in that: It includes a power supply, a first electric-controlled switch, a first photosensitive element, a triode, and a control chip; The first end of the first photosensitive element is electrically connected to the power supply via a resistor, and the second end of the first photosensitive element is grounded; One end of the first electronically controlled switch is electrically connected to the power supply, the other end of the first electronically controlled switch is electrically connected to the collector of the transistor, and the emitter of the transistor is grounded; The first pin of the control chip is electrically connected to the power supply, and the second pin of the control chip is electrically connected to the base of the transistor; The first end of the first photosensitive element is also electrically connected to the third pin of the control chip; the third pin of the control chip is used to obtain the voltage of the first end of the first photosensitive element; the fourth pin of the control chip is electrically connected to the line between the first end of the first photosensitive element and the third pin of the control chip via a resistor.

2. The light-operated switch control circuit according to claim 1, characterized in that: The first photosensitive element is a photoresistor, a photodiode or a phototransistor.

3. The light-operated switch control circuit according to claim 1, characterized in that: The light-operated switch control circuit is installed in a housing, and further includes a second photosensitive element arranged outside the housing, the second photosensitive element being used to directly sense the external light intensity; The first end of the second photosensitive element is electrically connected to the power supply via a resistor, and the second end of the second photosensitive element is grounded; the fifth pin of the control chip is electrically connected to the line between the first end of the second photosensitive element and the power supply; the fifth pin of the control chip is used to obtain the voltage of the first end of the second photosensitive element.

4. The light-operated switch control circuit according to claim 1, characterized in that: The power source is alternating current, and also includes a rectifier module for converting the power source into direct current, a filter module, and a step-down chip for converting the direct current into direct current with a lower voltage value.

5. The light-operated switch control circuit according to claim 1, characterized in that: The first electronically controlled switch is the coil part of a relay, and the switch part of the relay is connected to the power supply line of the controlled object.

6. A control method, used in the light-operated switch control circuit according to any one of claims 1 to 5, characterized in that: The control method comprises: Acquire the voltage value of the third pin of the control chip in real time; Determine whether the voltage value of the third pin of the control chip is higher than the first preset voltage, and if so, adjust the potential of the second pin of the control chip to a voltage value that turns on the transistor; It is determined whether the voltage value of the third pin of the control chip is lower than the second preset voltage. If it is determined to be yes, the potential of the second pin of the control chip is adjusted to a voltage value that cuts off the transistor.

7. The control method according to claim 6, characterized in that: The control method further comprises: When the voltage value of the third pin of the control chip reaches the first preset voltage, the output of the second pin is adjusted to a high potential, and the voltage value of the third pin is detected within a preset time length; wherein, when the voltage value of the third pin is detected to be lower than the first preset voltage within the preset time length, the voltage value of the third pin at this time is obtained as a recorded value, and the output of the fourth pin is adjusted to a high potential; When the voltage value of the third pin decreases by at least a preset voltage value based on the recorded value, the potential of the second pin is adjusted to a voltage value that cuts off the transistor.

8. A control method, used in the light-operated switch control circuit according to claim 3, characterized in that: The method comprises: When the light-operated switch control circuit is connected to only the first photosensitive element, the output voltage of the second pin is controlled according to the voltage value of the third pin; When the light-operated switch control circuit is connected to the first photosensitive element and the second photosensitive element at the same time, the voltage values ​​of the third pin and the fifth pin of the control chip are obtained in real time, the voltage value change of the fifth pin and the voltage value change of the third pin within a preset time length are calculated, and the magnitudes of the two changes are determined; Among them, when the change in the voltage value of the fifth pin within the preset time length is greater than the change in the voltage value of the third pin, the output voltage of the second pin is controlled according to the voltage value of the fifth pin; when the change in the voltage value of the fifth pin within the preset time length is less than the change in the voltage value of the third pin, the output voltage of the second pin is controlled according to the voltage value of the third pin.

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