CN205648088U - Light control automatic dimming circuit - Google Patents

Abstract

The utility model discloses a light -operated automatic dimmer circuit, including the power and with the LED lamps and lanterns that the source phase is connected be equipped with control switch between power and the LED lamps and lanterns the power with still be equipped with from light modulation control circuit between the LED lamps and lanterns, include first resistance, controlling resistor, photo resistance, fourth resistance, first triode, second triode and the 5th resistance from light modulation control circuit. The utility model has the advantages of simple structure, the simple operation, its accessible photo resistance cooperation controlling resistor realizes the brightness flop of LED lamps and lanterns, can the traditional LED lamps and lanterns of effectual solution can't be according to ambient brightness changes and with an automatic light meter not enough, the stability in use is good, just the practicality is good by force for the suitability.

Description

Light control automatic dimming circuit

technical field

The utility model relates to the technical field of LED dimming circuits, in particular to a light-controlled automatic dimming circuit.

Background technique

LED lamps have been widely used in people's daily life. There is a large difference in ambient illumination between day and night. Too high or too dark lamps will damage people's vision. How to realize the brightness of LED lamps to change with the change of ambient illumination through a simple circuit , when the ambient illuminance is high, the brightness of the lamps will be dimmed, and when the ambient illuminance is low, the brightness of the lamps will be brightened, which poses a major challenge to the design.

Utility model content

The main purpose of the utility model is to provide a light-controlled automatic dimming circuit, aiming to solve the problem that traditional LED lamps cannot be automatically dimmed according to changes in ambient brightness.

The utility model proposes a light-controlled automatic dimming circuit, which includes a power supply and an LED lamp connected to the power supply. A control switch is provided between the power supply and the LED lamp. There is also a self-dimming control circuit, the self-dimming control circuit includes a first resistor, an adjustable resistor, a photoresistor, a fourth resistor, a first triode, a second triode and a fifth resistor, so The output end of the control switch is connected to the emitter of the first triode, the collector of the first triode is connected to the anode of the LED lamp through a fifth resistor, and the first triode The base of the transistor is connected to the collector of the second triode, the emitter of the second triode is connected to the negative pole of the power supply, and the base of the first triode is connected in series The first resistor, the adjustable resistor and the photoresistor are connected to the base of the second triode, and the fourth resistor is connected between the base of the second triode and the negative pole of the power supply.

The first transistor is a PNP transistor, and the second transistor is an NPN transistor.

The adjustment range of the adjustable resistance is 0-50KΩ.

The resistance value range of the photosensitive resistor is 0-300KΩ.

The utility model has simple structure and convenient operation. It can realize the brightness change of the LED lamp through the photoresistor and the adjustable resistor, which can effectively solve the problem that the traditional LED lamp cannot be automatically adjusted according to the brightness change of the environment, and has good stability in use. Strong applicability and good practicability.

Description of drawings

Fig. 1 is the schematic diagram of the embodiment of the utility model.

The realization of the purpose of the utility model, functional characteristics and advantages will be further described in conjunction with the embodiments and with reference to the accompanying drawings.

detailed description

It should be understood that the specific embodiments described here are only used to explain the utility model, and are not intended to limit the utility model.

Referring to FIG. 1 , an embodiment of the present utility model is proposed, a light control automatic dimming circuit, comprising a power supply 1 and an LED lamp 2 connected to the power supply 1 , between the power supply 1 and the LED lamp 2 A control switch SW1 is provided, and a self-dimming control circuit 3 is provided between the power supply 1 and the LED lamp 2, and the self-dimming control circuit 3 includes a first resistor R1, an adjustable resistor R2, a photoresistor R3, the fourth resistor R4, the first transistor Q1, the second transistor Q2 and the fifth resistor R5, the output terminal of the control switch SW1 is connected to the emitter of the first transistor Q1, so The collector of the first triode Q1 is connected to the anode of the LED lamp 2 through the fifth resistor R5, and the base of the first triode Q1 is connected to the collector of the second triode Q2. The emitter of the second triode Q2 is connected to the negative pole of the power supply 1, and the base of the first triode Q1 passes through the first resistor R1, the adjustable resistor R2 and the photoresistor connected in series in sequence. R3 is connected to the base of the second transistor Q2, and the fourth resistor R4 is connected between the base of the second transistor Q2 and the negative pole of the power supply 1 .

The first transistor is a PNP transistor, and the second transistor is an NPN transistor.

The adjustment range of the adjustable resistance is 0-50KΩ.

The resistance value range of the photosensitive resistor is 0-300KΩ.

Its working principle is briefly described as follows: After the switch SW1 is closed, the LED lighting control circuit starts to work, and the transistors Q1 and Q2 are both in the conduction state; The pole current is small, Q2 is in the amplified state, and the base current of Q1 is controlled by Q2, so the current through the LED lamp is finally controlled by Q2. When the resistance of the photosensitive resistor R3 is large, Q1 is in the amplified state, and the brightness of the LED lamp is dim; As the ambient illuminance gradually dims, the resistance of the photoresistor R3 gradually decreases, resulting in a gradual increase in the brightness of the LED light; when the ambient illuminance is low, the resistance of the photoresistor R3 is small, Q1 is in a saturated state, and the brightness of the LED light is maximum; Therefore, the brightness of the LED lamp changes with the change of the ambient illuminance.

The utility model has simple structure and convenient operation. It can realize the brightness change of the LED lamp through the photoresistor and the adjustable resistor, which can effectively solve the problem that the traditional LED lamp cannot be automatically adjusted according to the brightness change of the environment, and has good stability in use. Strong applicability and good practicability.

The above are only preferred embodiments of the present utility model, and are not therefore limiting the patent scope of the present utility model. All equivalent structural transformations made by using the utility model specification and accompanying drawings are directly or indirectly used in other related technologies. Fields are all included in the scope of patent protection of the utility model in the same way.

Claims (4)

1. null1. a light-control automatic dimming circuit，Including power supply and the LED lamp that is connected with described power supply，Control switch it is provided with between described power supply and LED lamp，It is characterized in that: be additionally provided with from adjusting control circuit between described power supply and described LED lamp，Described include the first resistance from adjusting control circuit、Adjustable resistance、Photoconductive resistance、4th resistance、First audion、Second audion and the 5th resistance，The described outfan controlling switch is connected with the emitter stage of described first audion，The colelctor electrode of described first audion is connected with the positive pole of described LED lamp by the 5th resistance，The base stage of described first audion is connected with the colelctor electrode of described second audion，The emitter stage of described second audion is connected with the negative pole of described power supply，The base stage of described first audion is by the first resistance being sequentially connected in series、Adjustable resistor and photoconductive resistance are connected in the base stage of the second audion，Described 4th resistance is connected between base stage and the power cathode of described second audion.
2. Light-control automatic dimming circuit the most according to claim 1, it is characterised in that: described first audion is PNP type triode, and described second audion is NPN type triode.
3. Light-control automatic dimming circuit the most according to claim 2, it is characterised in that: the range of accommodation of described adjustable resistance is 0-50K Ω.
4. Light-control automatic dimming circuit the most according to claim 3, it is characterised in that: the resistance value scope of described photoconductive resistance is 0-300K Ω.